diff mbox

[v9,02/14] drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.

Message ID 1452611750-16283-3-git-send-email-p.zabel@pengutronix.de (mailing list archive)
State New, archived
Headers show

Commit Message

Philipp Zabel Jan. 12, 2016, 3:15 p.m. UTC
From: CK Hu <ck.hu@mediatek.com>

This patch adds an initial DRM driver for the Mediatek MT8173 DISP
subsystem. It currently supports two fixed output streams from the
OVL0/OVL1 sources to the DSI0/DPI0 sinks, respectively.

Signed-off-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: YT Shen <yt.shen@mediatek.com>
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
 drivers/gpu/drm/Kconfig                     |   2 +
 drivers/gpu/drm/Makefile                    |   1 +
 drivers/gpu/drm/mediatek/Kconfig            |  12 +
 drivers/gpu/drm/mediatek/Makefile           |  10 +
 drivers/gpu/drm/mediatek/mtk_disp_ovl.c     | 301 ++++++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c     | 603 ++++++++++++++++++++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_crtc.h     |  32 ++
 drivers/gpu/drm/mediatek/mtk_drm_ddp.c      | 355 ++++++++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_ddp.h      |  41 ++
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 275 +++++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h | 148 +++++++
 drivers/gpu/drm/mediatek/mtk_drm_drv.c      | 577 ++++++++++++++++++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_drv.h      |  52 +++
 drivers/gpu/drm/mediatek/mtk_drm_fb.c       | 165 ++++++++
 drivers/gpu/drm/mediatek/mtk_drm_fb.h       |  29 ++
 drivers/gpu/drm/mediatek/mtk_drm_gem.c      | 227 +++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_gem.h      |  55 +++
 drivers/gpu/drm/mediatek/mtk_drm_plane.c    | 242 +++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_plane.h    |  59 +++
 19 files changed, 3186 insertions(+)
 create mode 100644 drivers/gpu/drm/mediatek/Kconfig
 create mode 100644 drivers/gpu/drm/mediatek/Makefile
 create mode 100644 drivers/gpu/drm/mediatek/mtk_disp_ovl.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_crtc.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_crtc.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_ddp.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_ddp.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_drv.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_drv.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_fb.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_fb.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_gem.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_gem.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_plane.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_plane.h

Comments

Daniel Kurtz Jan. 20, 2016, 10:23 p.m. UTC | #1
Hi Philipp,

This driver is looking very good now to me.

Sorry for the delay reviewing.   Some comments inline below.

On Tue, Jan 12, 2016 at 7:15 AM, Philipp Zabel <p.zabel@pengutronix.de> wrote:
> From: CK Hu <ck.hu@mediatek.com>
>
> This patch adds an initial DRM driver for the Mediatek MT8173 DISP
> subsystem. It currently supports two fixed output streams from the
> OVL0/OVL1 sources to the DSI0/DPI0 sinks, respectively.
>
> Signed-off-by: CK Hu <ck.hu@mediatek.com>
> Signed-off-by: YT Shen <yt.shen@mediatek.com>
> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

[snip...]

> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> new file mode 100644
> index 0000000..455e62e
> --- /dev/null
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> @@ -0,0 +1,301 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <drm/drmP.h>
> +#include <linux/clk.h>
> +#include <linux/component.h>
> +#include <linux/of_device.h>
> +#include <linux/of_irq.h>
> +#include <linux/platform_device.h>
> +
> +#include "mtk_drm_crtc.h"
> +#include "mtk_drm_ddp_comp.h"
> +
> +#define DISP_REG_OVL_INTEN                     0x0004
> +#define OVL_FME_CPL_INT                                        BIT(1)
> +#define DISP_REG_OVL_INTSTA                    0x0008
> +#define DISP_REG_OVL_EN                                0x000c
> +#define DISP_REG_OVL_RST                       0x0014
> +#define DISP_REG_OVL_ROI_SIZE                  0x0020
> +#define DISP_REG_OVL_ROI_BGCLR                 0x0028
> +#define DISP_REG_OVL_SRC_CON                   0x002c
> +#define DISP_REG_OVL_CON(n)                    (0x0030 + 0x20 * (n))
> +#define DISP_REG_OVL_SRC_SIZE(n)               (0x0038 + 0x20 * (n))
> +#define DISP_REG_OVL_OFFSET(n)                 (0x003c + 0x20 * (n))
> +#define DISP_REG_OVL_PITCH(n)                  (0x0044 + 0x20 * (n))
> +#define DISP_REG_OVL_RDMA_CTRL(n)              (0x00c0 + 0x20 * (n))
> +#define DISP_REG_OVL_RDMA_GMC(n)               (0x00c8 + 0x20 * (n))
> +#define DISP_REG_OVL_ADDR(n)                   (0x0f40 + 0x20 * (n))
> +
> +enum OVL_INPUT_FORMAT {
> +       OVL_INFMT_RGB565 = 0,
> +       OVL_INFMT_RGB888 = 1,
> +       OVL_INFMT_RGBA8888 = 2,
> +       OVL_INFMT_ARGB8888 = 3,
> +};
> +
> +#define        OVL_RDMA_MEM_GMC        0x40402020
> +#define        OVL_AEN                 BIT(8)
> +#define        OVL_ALPHA               0xff
> +
> +/**
> + * struct mtk_disp_ovl - DISP_OVL driver structure
> + * @ddp_comp - structure containing type enum and hardware resources
> + * @drm_device - backlink to allow the irq handler to find the associated crtc
> + */
> +struct mtk_disp_ovl {
> +       struct mtk_ddp_comp             ddp_comp;
> +       struct drm_device               *drm_dev;

Storing the crtc here would be more consistent with the comment above.

> +};
> +
> +static irqreturn_t mtk_disp_ovl_irq_handler(int irq, void *dev_id)
> +{
> +       struct mtk_disp_ovl *priv = dev_id;
> +       struct mtk_ddp_comp *ovl = &priv->ddp_comp;
> +
> +       /* Clear frame completion interrupt */
> +       writel(0x0, ovl->regs + DISP_REG_OVL_INTSTA);
> +
> +       mtk_crtc_ddp_irq(priv->drm_dev, ovl);

Likewise, passing the crtc here would be a bit more consistent with the name
of this function mtk_crtc_ddp_irq().  Also, see below; if the CRTC is not found,
we can return IRQ_NONE here to indicate that this was a spurious
(unhandled) interrupt.

> +
> +       return IRQ_HANDLED;
> +}

[snip...]

> +static void mtk_ovl_layer_config(struct mtk_ddp_comp *comp, unsigned int idx,
> +               struct mtk_plane_state *state)
> +{
> +       struct mtk_plane_pending_state *pending = &state->pending;
> +       unsigned int addr = pending->addr;
> +       unsigned int pitch = pending->pitch & 0xffff;
> +       unsigned int fmt = pending->format;
> +       unsigned int offset = (pending->y << 16) | pending->x;
> +       unsigned int src_size = (pending->height << 16) | pending->width;
> +       unsigned int con;
> +
> +       con = has_rb_swapped(fmt) << 24 | ovl_fmt_convert(fmt) << 12;

Since has_rb_swapped() and ovl_fmt_convert() can theoretically fail, but we
can't fail here during .layer_config, can we instead do this in an atomic state
check phase, and just store the resulting .has_rb_swapped and .ovl_infmt values
to mtk_plane_pending_state for later application during .layer_config?

> +       if (idx != 0)
> +               con |= OVL_AEN | OVL_ALPHA;
> +
> +       writel(con, comp->regs + DISP_REG_OVL_CON(idx));
> +       writel(pitch, comp->regs + DISP_REG_OVL_PITCH(idx));
> +       writel(src_size, comp->regs + DISP_REG_OVL_SRC_SIZE(idx));
> +       writel(offset, comp->regs + DISP_REG_OVL_OFFSET(idx));
> +       writel(addr, comp->regs + DISP_REG_OVL_ADDR(idx));

Can the above all be writel_relaxed() ?

> +}

[snip...]

> +static int mtk_crtc_ddp_hw_init(struct mtk_drm_crtc *mtk_crtc)
> +{
> +       struct drm_crtc *crtc = &mtk_crtc->base;
> +       unsigned int width, height, vrefresh;
> +       int ret;
> +       int i;
> +
> +       DRM_DEBUG_DRIVER("%s\n", __func__);
> +       if (WARN_ON(!crtc->state))
> +               return -EINVAL;
> +
> +       width = crtc->state->adjusted_mode.hdisplay;
> +       height = crtc->state->adjusted_mode.vdisplay;
> +       vrefresh = crtc->state->adjusted_mode.vrefresh;
> +
> +       ret = pm_runtime_get_sync(crtc->dev->dev);
> +       if (ret < 0) {
> +               DRM_ERROR("Failed to enable power domain: %d\n", ret);
> +               return ret;
> +       }
> +
> +       ret = mtk_disp_mutex_prepare(mtk_crtc->mutex);
> +       if (ret < 0) {
> +               DRM_ERROR("Failed to enable mutex clock: %d\n", ret);
> +               goto err_pm_runtime_put;
> +       }
> +
> +       ret = mtk_crtc_ddp_clk_enable(mtk_crtc);
> +       if (ret < 0) {
> +               DRM_ERROR("Failed to enable component clocks: %d\n", ret);
> +               goto err_mutex_unprepare;
> +       }
> +
> +       DRM_DEBUG_DRIVER("mediatek_ddp_ddp_path_setup\n");
> +       for (i = 0; i < mtk_crtc->ddp_comp_nr - 1; i++) {
> +               mtk_ddp_add_comp_to_path(mtk_crtc->config_regs,
> +                                        mtk_crtc->ddp_comp[i]->id,
> +                                        mtk_crtc->ddp_comp[i + 1]->id);
> +               mtk_disp_mutex_add_comp(mtk_crtc->mutex,
> +                                       mtk_crtc->ddp_comp[i]->id);
> +       }
> +       mtk_disp_mutex_add_comp(mtk_crtc->mutex, mtk_crtc->ddp_comp[i]->id);
> +       mtk_disp_mutex_enable(mtk_crtc->mutex);
> +
> +       DRM_DEBUG_DRIVER("ddp_disp_path_power_on %dx%d\n", width, height);

I think this debug message is now stale?

> +       for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
> +               struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[i];
> +
> +               mtk_ddp_comp_config(comp, width, height, vrefresh);
> +               mtk_ddp_comp_start(comp);
> +       }
> +
> +       return 0;
> +
> +err_mutex_unprepare:
> +       mtk_disp_mutex_unprepare(mtk_crtc->mutex);
> +err_pm_runtime_put:
> +       pm_runtime_put(crtc->dev->dev);
> +       return ret;
> +}

[snip...]

> +void mtk_drm_crtc_check_flush(struct drm_crtc *crtc)
> +{
> +       struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> +       int i;
> +
> +       if (mtk_crtc->do_flush) {
> +               if (mtk_crtc->event)
> +                       mtk_crtc->pending_needs_vblank = true;
> +               for (i = 0; i < OVL_LAYER_NR; i++) {
> +                       struct drm_plane *plane = &mtk_crtc->planes[i].base;
> +                       struct mtk_plane_state *plane_state;
> +
> +                       plane_state = to_mtk_plane_state(plane->state);
> +                       if (plane_state->pending.dirty) {
> +                               plane_state->pending.config = true;
> +                               plane_state->pending.dirty = false;
> +                       }
> +               }
> +               mtk_crtc->pending_planes = true;

Only set pending_planes is true iff at least 1 of the ovl was
pending.dirty, right?

> +               mtk_crtc->do_flush = false;
> +       }
> +}
> +
> +static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc,
> +                                     struct drm_crtc_state *old_crtc_state)
> +{
> +       struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> +
> +       mtk_crtc->do_flush = true;
> +       mtk_drm_crtc_check_flush(crtc);

I can't figure out how this is supposed to work.
mtk_drm_crtc_check_flush() only does something if do_flush is set.
And, do_flush is only set here in mtk_drm_crtc_atomic_flush(), just
above mtk_drm_crtc_check_flush(), and it is cleared by that function.

So, why do we also call mtk_drm_crtc_check_flush() from
mtk_plane_atomic_update()?
In what condition will the call to mtk_drm_crtc_check_flush() from
mtk_plane_atomic_update() have do_flush == true?

> +}

[snip...]

> +void mtk_crtc_ddp_irq(struct drm_device *drm_dev, struct mtk_ddp_comp *ovl)
> +{
> +       struct mtk_drm_private *priv = drm_dev->dev_private;
> +       struct mtk_drm_crtc *mtk_crtc;
> +       struct mtk_crtc_state *state;
> +       unsigned int i;
> +
> +       mtk_crtc = mtk_crtc_by_src_comp(priv, ovl);

Hmm.  Can we do this lookup once and store it somewhere to avoid this
lookup during every IRQ?

> +       if (WARN_ON(!mtk_crtc))
> +               return;

I think the typical thing to do if we can't handle an interrupt is to
return IRQ_NONE, so that it can be tracked by the kernel's spurious
interrupt infrastructure.  We can probably remove the WARN_ON, too.

> +
> +       state = to_mtk_crtc_state(mtk_crtc->base.state);
> +
> +       /*
> +        * TODO: instead of updating the registers here, we should prepare
> +        * working registers in atomic_commit and let the hardware command
> +        * queue update module registers on vblank.
> +        */
> +       if (state->pending_config) {
> +               mtk_ddp_comp_config(ovl, state->pending_width,
> +                                   state->pending_height,
> +                                   state->pending_vrefresh);
> +
> +               state->pending_config = false;
> +       }
> +
> +       if (mtk_crtc->pending_planes) {
> +               for (i = 0; i < OVL_LAYER_NR; i++) {
> +                       struct drm_plane *plane = &mtk_crtc->planes[i].base;
> +                       struct mtk_plane_state *plane_state;
> +
> +                       plane_state = to_mtk_plane_state(plane->state);
> +
> +                       if (plane_state->pending.config) {
> +                               if (!plane_state->pending.enable)
> +                                       mtk_ddp_comp_layer_off(ovl, i);
> +
> +                               mtk_ddp_comp_layer_config(ovl, i, plane_state);
> +
> +                               if (plane_state->pending.enable)
> +                                       mtk_ddp_comp_layer_on(ovl, i);

.layer_off() and .layer_on() are redundant, and can just be handled inside
.layer_config(), since we pass plane_state to .layer_config() anyway.

That will also be slightly more efficient, since the mtk_ddp_comp_layer*() will
then all be static functions in the same file and on/off can be inlined.

> +
> +                               plane_state->pending.config = false;
> +                       }
> +               }
> +               mtk_crtc->pending_planes = false;
> +       }
> +
> +       mtk_drm_finish_page_flip(mtk_crtc);
> +}

[snip...]

> +
> +struct mtk_ddp_comp_match {
> +       enum mtk_ddp_comp_type type;
> +       int alias_id;
> +       const struct mtk_ddp_comp_funcs *funcs;
> +};
> +
> +static struct mtk_ddp_comp_match mtk_ddp_matches[DDP_COMPONENT_ID_MAX] = {

static const struct ...

> +       [DDP_COMPONENT_AAL]     = { MTK_DISP_AAL,       0, NULL },
> +       [DDP_COMPONENT_COLOR0]  = { MTK_DISP_COLOR,     0, &ddp_color },
> +       [DDP_COMPONENT_COLOR1]  = { MTK_DISP_COLOR,     1, &ddp_color },
> +       [DDP_COMPONENT_DPI0]    = { MTK_DPI,            0, NULL },
> +       [DDP_COMPONENT_DSI0]    = { MTK_DSI,            0, NULL },
> +       [DDP_COMPONENT_DSI1]    = { MTK_DSI,            1, NULL },
> +       [DDP_COMPONENT_GAMMA]   = { MTK_DISP_GAMMA,     0, NULL },
> +       [DDP_COMPONENT_OD]      = { MTK_DISP_OD,        0, &ddp_od },
> +       [DDP_COMPONENT_OVL0]    = { MTK_DISP_OVL,       0, NULL },
> +       [DDP_COMPONENT_OVL1]    = { MTK_DISP_OVL,       1, NULL },
> +       [DDP_COMPONENT_PWM0]    = { MTK_DISP_PWM,       0, NULL },
> +       [DDP_COMPONENT_RDMA0]   = { MTK_DISP_RDMA,      0, &ddp_rdma },
> +       [DDP_COMPONENT_RDMA1]   = { MTK_DISP_RDMA,      1, &ddp_rdma },
> +       [DDP_COMPONENT_RDMA2]   = { MTK_DISP_RDMA,      2, &ddp_rdma },
> +       [DDP_COMPONENT_UFOE]    = { MTK_DISP_UFOE,      0, &ddp_ufoe },
> +       [DDP_COMPONENT_WDMA0]   = { MTK_DISP_WDMA,      0, NULL },
> +       [DDP_COMPONENT_WDMA1]   = { MTK_DISP_WDMA,      1, NULL },
> +};

[snip...]

> +int mtk_ddp_comp_init(struct device *dev, struct device_node *node,
> +                     struct mtk_ddp_comp *comp, enum mtk_ddp_comp_id comp_id,
> +                     const struct mtk_ddp_comp_funcs *funcs)
> +{
> +       enum mtk_ddp_comp_type type;
> +       struct device_node *larb_node;
> +       struct platform_device *larb_pdev;
> +
> +       if (comp_id < 0 || comp_id >= DDP_COMPONENT_ID_MAX)
> +               return -EINVAL;
> +
> +       comp->id = comp_id;
> +       comp->funcs = funcs ?: mtk_ddp_matches[comp_id].funcs;
> +
> +       if (comp_id == DDP_COMPONENT_DPI0 ||
> +           comp_id == DDP_COMPONENT_DSI0 ||
> +           comp_id == DDP_COMPONENT_PWM0) {
> +               comp->regs = NULL;
> +               comp->clk = NULL;
> +               comp->irq = 0;
> +               return 0;
> +       }
> +
> +       comp->regs = of_iomap(node, 0);
> +       comp->irq = of_irq_get(node, 0);
> +       comp->clk = of_clk_get(node, 0);
> +       if (IS_ERR(comp->clk))
> +               comp->clk = NULL;
> +
> +       type = mtk_ddp_matches[comp_id].type;
> +
> +       /* Only DMA capable components need the LARB property */
> +       comp->larb_dev = NULL;
> +       if (type != MTK_DISP_OVL &&
> +           type != MTK_DISP_RDMA &&
> +           type != MTK_DISP_WDMA)
> +               return 0;
> +
> +       larb_node = of_parse_phandle(node, "mediatek,larb", 0);

Need to call of_node_put() for larb_node somewhere.

> +       if (!larb_node) {
> +               dev_err(dev,
> +                       "Missing mediadek,larb phandle in %s node\n",
> +                       node->full_name);
> +               return -EINVAL;
> +       }
> +
> +       larb_pdev = of_find_device_by_node(larb_node);
> +       if (!larb_pdev) {
> +               dev_warn(dev, "Waiting for larb device %s\n",
> +                        larb_node->full_name);
> +               return -EPROBE_DEFER;
> +       }
> +
> +       comp->larb_dev = &larb_pdev->dev;
> +
> +       return 0;
> +}

[snip...]

> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fb.h b/drivers/gpu/drm/mediatek/mtk_drm_fb.h
> new file mode 100644
> index 0000000..a89c7af
> --- /dev/null
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_fb.h
> @@ -0,0 +1,29 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#ifndef MTK_DRM_FB_H
> +#define MTK_DRM_FB_H
> +
> +#define MAX_FB_OBJ     3

Remove from this patch

> +
> +struct drm_gem_object *mtk_fb_get_gem_obj(struct drm_framebuffer *fb);
> +int mtk_fb_wait(struct drm_framebuffer *fb);
> +struct drm_framebuffer *mtk_drm_mode_fb_create(struct drm_device *dev,
> +                                              struct drm_file *file,
> +                                              struct drm_mode_fb_cmd2 *cmd);
> +
> +void mtk_drm_mode_output_poll_changed(struct drm_device *dev);
> +int mtk_fbdev_create(struct drm_device *dev);
> +void mtk_fbdev_destroy(struct drm_device *dev);

Remove these last three function prototypes from this patch.

> +
> +#endif /* MTK_DRM_FB_H */
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> new file mode 100644
> index 0000000..96cc980
> --- /dev/null
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> @@ -0,0 +1,227 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <drm/drmP.h>
> +#include <drm/drm_gem.h>
> +
> +#include "mtk_drm_gem.h"
> +
> +static struct mtk_drm_gem_obj *mtk_drm_gem_init(struct drm_device *dev,
> +                                               unsigned long size)

nit: I think these "size in bytes" parameters should use size_t.

> +{
> +       struct mtk_drm_gem_obj *mtk_gem_obj;
> +       int ret;
> +
> +       size = round_up(size, PAGE_SIZE);
> +
> +       mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL);
> +       if (!mtk_gem_obj)
> +               return ERR_PTR(-ENOMEM);
> +
> +       ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size);
> +       if (ret < 0) {
> +               DRM_ERROR("failed to initialize gem object\n");
> +               kfree(mtk_gem_obj);
> +               return ERR_PTR(ret);
> +       }
> +
> +       return mtk_gem_obj;
> +}
> +
> +struct mtk_drm_gem_obj *mtk_drm_gem_create(struct drm_device *dev,
> +                                          unsigned long size, bool alloc_kmap)
> +{
> +       struct mtk_drm_gem_obj *mtk_gem;
> +       struct drm_gem_object *obj;
> +       int ret;
> +
> +       mtk_gem = mtk_drm_gem_init(dev, size);
> +       if (IS_ERR(mtk_gem))
> +               return ERR_CAST(mtk_gem);
> +
> +       obj = &mtk_gem->base;
> +
> +       init_dma_attrs(&mtk_gem->dma_attrs);
> +       dma_set_attr(DMA_ATTR_WRITE_COMBINE, &mtk_gem->dma_attrs);
> +
> +       if (!alloc_kmap)
> +               dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &mtk_gem->dma_attrs);
> +
> +       mtk_gem->cookie = dma_alloc_attrs(dev->dev, obj->size,
> +                               (dma_addr_t *)&mtk_gem->dma_addr, GFP_KERNEL,

Cast here is not necessary, since dma_addr is dma_addr_t.

> +                               &mtk_gem->dma_attrs);
> +       if (!mtk_gem->cookie) {
> +               DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size);
> +               ret = -ENOMEM;
> +               goto err_gem_free;
> +       }
> +
> +       if (alloc_kmap)
> +               mtk_gem->kvaddr = mtk_gem->cookie;
> +
> +       DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad\n",
> +                        mtk_gem->cookie, &mtk_gem->dma_addr);

Print size too.

> +
> +       return mtk_gem;
> +
> +err_gem_free:
> +       drm_gem_object_release(obj);
> +       kfree(mtk_gem);
> +       return ERR_PTR(ret);
> +}
> +
> +void mtk_drm_gem_free_object(struct drm_gem_object *obj)
> +{
> +       struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
> +
> +       dma_free_attrs(obj->dev->dev, obj->size, mtk_gem->cookie,
> +                      mtk_gem->dma_addr, &mtk_gem->dma_attrs);
> +
> +       /* release file pointer to gem object. */
> +       drm_gem_object_release(obj);
> +
> +       kfree(mtk_gem);
> +}
> +
> +int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
> +                           struct drm_mode_create_dumb *args)
> +{
> +       struct mtk_drm_gem_obj *mtk_gem;
> +       int ret;
> +
> +       args->pitch = args->width * DIV_ROUND_UP(args->bpp, 8);

Perhaps this more correctly aligns the pitch (this is what cma does):
  args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);

> +       args->size = args->pitch * args->height;
> +
> +       mtk_gem = mtk_drm_gem_create(dev, args->size, false);
> +       if (IS_ERR(mtk_gem))
> +               return PTR_ERR(mtk_gem);
> +
> +       /*
> +        * allocate a id of idr table where the obj is registered
> +        * and handle has the id what user can see.
> +        */
> +       ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args->handle);
> +       if (ret)
> +               goto err_handle_create;
> +
> +       /* drop reference from allocate - handle holds it now. */
> +       drm_gem_object_unreference_unlocked(&mtk_gem->base);
> +
> +       return 0;
> +
> +err_handle_create:
> +       mtk_drm_gem_free_object(&mtk_gem->base);
> +       return ret;
> +}
> +
> +int mtk_drm_gem_dumb_map_offset(struct drm_file *file_priv,
> +                               struct drm_device *dev, uint32_t handle,
> +                               uint64_t *offset)
> +{
> +       struct drm_gem_object *obj;
> +       int ret;
> +

The cma helper locks struct_mutex here.

> +       obj = drm_gem_object_lookup(dev, file_priv, handle);
> +       if (!obj) {
> +               DRM_ERROR("failed to lookup gem object.\n");
> +               return -EINVAL;
> +       }
> +
> +       ret = drm_gem_create_mmap_offset(obj);
> +       if (ret)
> +               goto out;
> +
> +       *offset = drm_vma_node_offset_addr(&obj->vma_node);
> +       DRM_DEBUG_KMS("offset = 0x%llx\n", *offset);
> +
> +out:
> +       drm_gem_object_unreference_unlocked(obj);
> +       return ret;
> +}

[snip...]

> +/*
> + * Allocate a sg_table for this GEM object.
> + * Note: Both the table's contents, and the sg_table itself must be freed by
> + *       the caller.
> + * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
> + */
> +struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj)
> +{
> +       struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
> +       struct drm_device *drm = obj->dev;
> +       struct sg_table *sgt;
> +       int ret;
> +
> +       sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
> +       if (!sgt)
> +               return ERR_PTR(-ENOMEM);
> +
> +       ret = dma_get_sgtable_attrs(drm->dev, sgt, mtk_gem->cookie,
> +                                   mtk_gem->dma_addr, obj->size,
> +                                   &mtk_gem->dma_attrs);
> +       if (ret) {
> +               DRM_ERROR("failed to allocate sgt, %d\n", ret);
> +               kfree(sgt);
> +               return ERR_PTR(ret);
> +       }
> +
> +       return sgt;
> +}

Do we also want a prime_import_sg_table() here for importing foreign allocated
dma bufs for display?

[snip...]

> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> new file mode 100644
> index 0000000..e9b6bf6
> --- /dev/null
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> @@ -0,0 +1,242 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + * Author: CK Hu <ck.hu@mediatek.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <drm/drmP.h>
> +#include <drm/drm_atomic.h>
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_plane_helper.h>
> +
> +#include "mtk_drm_crtc.h"
> +#include "mtk_drm_ddp_comp.h"
> +#include "mtk_drm_drv.h"
> +#include "mtk_drm_fb.h"
> +#include "mtk_drm_gem.h"
> +#include "mtk_drm_plane.h"
> +
> +static const uint32_t formats[] = {
> +       DRM_FORMAT_XRGB8888,
> +       DRM_FORMAT_ARGB8888,
> +       DRM_FORMAT_RGB565,
> +};
> +
> +static void mtk_plane_enable(struct mtk_drm_plane *mtk_plane, bool enable,
> +                            dma_addr_t addr, struct drm_rect *dest)
> +{
> +       struct drm_plane *plane = &mtk_plane->base;
> +       struct mtk_plane_state *state = to_mtk_plane_state(plane->state);
> +       unsigned int pitch, format;
> +       int x, y;
> +
> +       if (WARN_ON(!plane->state || (enable && !plane->state->fb)))
> +               return;
> +
> +       if (plane->state->fb) {
> +               pitch = plane->state->fb->pitches[0];
> +               format = plane->state->fb->pixel_format;
> +       } else {
> +               pitch = 0;
> +               format = DRM_FORMAT_RGBA8888;
> +       }
> +
> +       x = plane->state->crtc_x;
> +       y = plane->state->crtc_y;
> +
> +       if (x < 0) {
> +               addr -= x * 4;
> +               x = 0;
> +       }
> +
> +       if (y < 0) {
> +               addr -= y * pitch;
> +               y = 0;
> +       }
> +
> +       state->pending.enable = enable;
> +       state->pending.pitch = pitch;
> +       state->pending.format = format;
> +       state->pending.addr = addr;
> +       state->pending.x = x;
> +       state->pending.y = y;
> +       state->pending.width = dest->x2 - dest->x1;
> +       state->pending.height = dest->y2 - dest->y1;

wmb(); ?

BTW, it is a good idea to document all wmb() calls.
If you forget, I believe checkpatch.pl will remind you.

> +       state->pending.dirty = true;
> +}
> +

That's it!

Thanks,
-Dan
Daniel Kurtz Feb. 2, 2016, 5:12 p.m. UTC | #2
Hi Philipp,

Sorry for the previous HTML email.  Trying again...

Below are some more comments from my observations today trying to configure
Mediatek DRM to use just the MIPI/DSI path (no HDMI).

On Tue, Jan 12, 2016 at 11:15 PM, Philipp Zabel <p.zabel@pengutronix.de> wrote:
> From: CK Hu <ck.hu@mediatek.com>
>
> This patch adds an initial DRM driver for the Mediatek MT8173 DISP
> subsystem. It currently supports two fixed output streams from the
> OVL0/OVL1 sources to the DSI0/DPI0 sinks, respectively.
>
> Signed-off-by: CK Hu <ck.hu@mediatek.com>
> Signed-off-by: YT Shen <yt.shen@mediatek.com>
> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

[snip]

> +int mtk_drm_crtc_create(struct drm_device *drm_dev,
> +                       const enum mtk_ddp_comp_id *path, unsigned int path_len)
> +{
> +       struct mtk_drm_private *priv = drm_dev->dev_private;
> +       struct device *dev = drm_dev->dev;
> +       struct mtk_drm_crtc *mtk_crtc;
> +       enum drm_plane_type type;
> +       unsigned int zpos;
> +       int pipe = priv->num_pipes;
> +       int ret;
> +       int i;
> +
> +       mtk_crtc = devm_kzalloc(dev, sizeof(*mtk_crtc), GFP_KERNEL);
> +       if (!mtk_crtc)
> +               return -ENOMEM;
> +
> +       mtk_crtc->config_regs = priv->config_regs;
> +       mtk_crtc->ddp_comp_nr = path_len;
> +       mtk_crtc->ddp_comp = devm_kmalloc_array(dev, mtk_crtc->ddp_comp_nr,
> +                                               sizeof(*mtk_crtc->ddp_comp),
> +                                               GFP_KERNEL);
> +
> +       mtk_crtc->mutex = mtk_disp_mutex_get(priv->mutex_dev, pipe);
> +       if (IS_ERR(mtk_crtc->mutex)) {
> +               ret = PTR_ERR(mtk_crtc->mutex);
> +               dev_err(dev, "Failed to get mutex: %d\n", ret);
> +               return ret;
> +       }
> +
> +       for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
> +               enum mtk_ddp_comp_id comp_id = path[i];
> +               struct mtk_ddp_comp *comp;
> +
> +               comp = priv->ddp_comp[comp_id];
> +               if (!comp) {
> +                       dev_err(dev, "Component %s not initialized\n",
> +                               priv->comp_node[comp_id]->full_name);

If one of the components is disabled in .dtsi, then its
priv->comp_node[comp_id] will be NULL here, and trying to full_name will OOPS.


> +                       ret = -ENODEV;
> +                       goto unprepare;
> +               }
> +
> +               ret = clk_prepare(comp->clk);
> +               if (ret) {
> +                       dev_err(dev,
> +                               "Failed to prepare clock for component %s: %d\n",
> +                               priv->comp_node[comp_id]->full_name, ret);
> +                       goto unprepare;
> +               }
> +
> +               mtk_crtc->ddp_comp[i] = comp;
> +       }
> +
> +       for (zpos = 0; zpos < OVL_LAYER_NR; zpos++) {
> +               type = (zpos == 0) ? DRM_PLANE_TYPE_PRIMARY :
> +                               (zpos == 1) ? DRM_PLANE_TYPE_CURSOR :
> +                                               DRM_PLANE_TYPE_OVERLAY;
> +               ret = mtk_plane_init(drm_dev, &mtk_crtc->planes[zpos],
> +                                    BIT(pipe), type, zpos);
> +               if (ret)
> +                       goto unprepare;
> +       }
> +
> +       ret = mtk_drm_crtc_init(drm_dev, mtk_crtc, &mtk_crtc->planes[0].base,
> +                               &mtk_crtc->planes[1].base, pipe);
> +       if (ret < 0)
> +               goto unprepare;
> +
> +       priv->crtc[pipe] = &mtk_crtc->base;
> +       priv->num_pipes++;
> +
> +       return 0;
> +
> +unprepare:
> +       while (--i >= 0)
> +               clk_unprepare(mtk_crtc->ddp_comp[i]->clk);
> +
> +       return ret;
> +}

> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> new file mode 100644
> index 0000000..9db22b4
> --- /dev/null
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c

[snip]

> +static struct drm_driver mtk_drm_driver = {
> +       .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME |
> +                          DRIVER_ATOMIC,
> +       .unload = mtk_drm_unload,
> +       .set_busid = drm_platform_set_busid,

I think using drm_platform_set_busid() as our .set_busid may cause an OOPs if
userspace does DRM_IOCTL_SET_VERSION.

drm_setversion() will calls drm_set_busid(), which calls
dev->driver->set_busid()
drm_platform_set_busid() accesses dev->platformdev->id.

However, dev->platformdev is only set by:
  drm_platform_init()->drm_get_platform_dev()

And, since mtk_drm_bind() does the drm_dev_alloc() /
drm_dev_register() itself instead
of calling drm_get_platform_dev(), so dev->platformdev will still be NULL.

So, why don't we call drm_platform_init() instead and implement a .load callback
to do mtk_drm_kms_init()?

> +
> +       .get_vblank_counter = drm_vblank_count,
> +       .enable_vblank = mtk_drm_crtc_enable_vblank,
> +       .disable_vblank = mtk_drm_crtc_disable_vblank,
> +
> +       .gem_free_object = mtk_drm_gem_free_object,
> +       .gem_vm_ops = &mtk_drm_gem_vm_ops,
> +       .dumb_create = mtk_drm_gem_dumb_create,
> +       .dumb_map_offset = mtk_drm_gem_dumb_map_offset,
> +       .dumb_destroy = drm_gem_dumb_destroy,
> +
> +       .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
> +       .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
> +       .gem_prime_export = drm_gem_prime_export,
> +       .gem_prime_import = drm_gem_prime_import,
> +       .gem_prime_get_sg_table = mtk_gem_prime_get_sg_table,
> +       .gem_prime_mmap = mtk_drm_gem_mmap_buf,
> +       .fops = &mtk_drm_fops,
> +
> +       .name = DRIVER_NAME,
> +       .desc = DRIVER_DESC,
> +       .date = DRIVER_DATE,
> +       .major = DRIVER_MAJOR,
> +       .minor = DRIVER_MINOR,
> +};
> +
> +static int compare_of(struct device *dev, void *data)
> +{
> +       return dev->of_node == data;
> +}
> +
> +static int mtk_drm_bind(struct device *dev)
> +{
> +       struct mtk_drm_private *private = dev_get_drvdata(dev);
> +       struct drm_device *drm;
> +       int ret;
> +
> +       drm = drm_dev_alloc(&mtk_drm_driver, dev);
> +       if (!drm)
> +               return -ENOMEM;
> +
> +       drm_dev_set_unique(drm, dev_name(dev));
> +
> +       ret = drm_dev_register(drm, 0);
> +       if (ret < 0)
> +               goto err_free;
> +
> +       drm->dev_private = private;
> +       private->drm = drm;
> +
> +       ret = mtk_drm_kms_init(drm);
> +       if (ret < 0)
> +               goto err_unregister;
> +
> +       return 0;
> +
> +err_unregister:
> +       drm_dev_unregister(drm);
> +err_free:
> +       drm_dev_unref(drm);
> +       return ret;
> +}
Philipp Zabel Feb. 3, 2016, 2:31 p.m. UTC | #3
Hi Daniel,

Am Mittwoch, den 20.01.2016, 14:23 -0800 schrieb Daniel Kurtz:
> Hi Philipp,
> 
> This driver is looking very good now to me.
> 
> Sorry for the delay reviewing.   Some comments inline below.
[...]
> > diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> > new file mode 100644
> > index 0000000..455e62e
> > --- /dev/null
> > +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
[...]
> > +/**
> > + * struct mtk_disp_ovl - DISP_OVL driver structure
> > + * @ddp_comp - structure containing type enum and hardware resources
> > + * @drm_device - backlink to allow the irq handler to find the associated crtc
> > + */
> > +struct mtk_disp_ovl {
> > +       struct mtk_ddp_comp             ddp_comp;
> > +       struct drm_device               *drm_dev;
> 
> Storing the crtc here would be more consistent with the comment above.

Ok.

> > +};
> > +
> > +static irqreturn_t mtk_disp_ovl_irq_handler(int irq, void *dev_id)
> > +{
> > +       struct mtk_disp_ovl *priv = dev_id;
> > +       struct mtk_ddp_comp *ovl = &priv->ddp_comp;
> > +
> > +       /* Clear frame completion interrupt */
> > +       writel(0x0, ovl->regs + DISP_REG_OVL_INTSTA);
> > +
> > +       mtk_crtc_ddp_irq(priv->drm_dev, ovl);
> 
> Likewise, passing the crtc here would be a bit more consistent with the name
> of this function mtk_crtc_ddp_irq().  Also, see below; if the CRTC is not found,
> we can return IRQ_NONE here to indicate that this was a spurious
> (unhandled) interrupt.

Ok.

> > +
> > +       return IRQ_HANDLED;
> > +}
> 
> [snip...]
> 
> > +static void mtk_ovl_layer_config(struct mtk_ddp_comp *comp, unsigned int idx,
> > +               struct mtk_plane_state *state)
> > +{
> > +       struct mtk_plane_pending_state *pending = &state->pending;
> > +       unsigned int addr = pending->addr;
> > +       unsigned int pitch = pending->pitch & 0xffff;
> > +       unsigned int fmt = pending->format;
> > +       unsigned int offset = (pending->y << 16) | pending->x;
> > +       unsigned int src_size = (pending->height << 16) | pending->width;
> > +       unsigned int con;
> > +
> > +       con = has_rb_swapped(fmt) << 24 | ovl_fmt_convert(fmt) << 12;
> 
> Since has_rb_swapped() and ovl_fmt_convert() can theoretically fail, but we
> can't fail here during .layer_config, can we instead do this in an atomic state
> check phase, and just store the resulting .has_rb_swapped and .ovl_infmt values
> to mtk_plane_pending_state for later application during .layer_config?

I'd rather keep the OVL specific bitfields contained in mtk_disp_ovl.c
in case we want to use RDMA planes later.

But I can change the conversion functions not to throw an error and move
the check up into the atomic plane check code.

> > +       if (idx != 0)
> > +               con |= OVL_AEN | OVL_ALPHA;
> > +
> > +       writel(con, comp->regs + DISP_REG_OVL_CON(idx));
> > +       writel(pitch, comp->regs + DISP_REG_OVL_PITCH(idx));
> > +       writel(src_size, comp->regs + DISP_REG_OVL_SRC_SIZE(idx));
> > +       writel(offset, comp->regs + DISP_REG_OVL_OFFSET(idx));
> > +       writel(addr, comp->regs + DISP_REG_OVL_ADDR(idx));
> 
> Can the above all be writel_relaxed() ?

Yes.

[...]
> > +static int mtk_crtc_ddp_hw_init(struct mtk_drm_crtc *mtk_crtc)
> > +{
[...]
> > +       mtk_disp_mutex_add_comp(mtk_crtc->mutex, mtk_crtc->ddp_comp[i]->id);
> > +       mtk_disp_mutex_enable(mtk_crtc->mutex);
> > +
> > +       DRM_DEBUG_DRIVER("ddp_disp_path_power_on %dx%d\n", width, height);
> 
> I think this debug message is now stale?

I'll remove it.

[...]
> > +void mtk_drm_crtc_check_flush(struct drm_crtc *crtc)
> > +{
> > +       struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> > +       int i;
> > +
> > +       if (mtk_crtc->do_flush) {
> > +               if (mtk_crtc->event)
> > +                       mtk_crtc->pending_needs_vblank = true;
> > +               for (i = 0; i < OVL_LAYER_NR; i++) {
> > +                       struct drm_plane *plane = &mtk_crtc->planes[i].base;
> > +                       struct mtk_plane_state *plane_state;
> > +
> > +                       plane_state = to_mtk_plane_state(plane->state);
> > +                       if (plane_state->pending.dirty) {
> > +                               plane_state->pending.config = true;
> > +                               plane_state->pending.dirty = false;
> > +                       }
> > +               }
> > +               mtk_crtc->pending_planes = true;
> 
> Only set pending_planes is true iff at least 1 of the ovl was
> pending.dirty, right?

Right.

[...]
> > +static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc,
> > +                                     struct drm_crtc_state *old_crtc_state)
> > +{
> > +       struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> > +
> > +       mtk_crtc->do_flush = true;
> > +       mtk_drm_crtc_check_flush(crtc);
> 
> I can't figure out how this is supposed to work.
> mtk_drm_crtc_check_flush() only does something if do_flush is set.
> And, do_flush is only set here in mtk_drm_crtc_atomic_flush(), just
> above mtk_drm_crtc_check_flush(), and it is cleared by that function.
> 
> So, why do we also call mtk_drm_crtc_check_flush() from
> mtk_plane_atomic_update()?
> In what condition will the call to mtk_drm_crtc_check_flush() from
> mtk_plane_atomic_update() have do_flush == true?

Hm, me neither. With the CMDQ update this will all vanish anyway. I'll
check if I can just merge this into mtk_drm_crtc_atomic_flush() and get
rid of the call from mtk_plane_atomic_update().

[...]
> > +void mtk_crtc_ddp_irq(struct drm_device *drm_dev, struct mtk_ddp_comp *ovl)
> > +{
> > +       struct mtk_drm_private *priv = drm_dev->dev_private;
> > +       struct mtk_drm_crtc *mtk_crtc;
> > +       struct mtk_crtc_state *state;
> > +       unsigned int i;
> > +
> > +       mtk_crtc = mtk_crtc_by_src_comp(priv, ovl);
> 
> Hmm.  Can we do this lookup once and store it somewhere to avoid this
> lookup during every IRQ?

Yes. I'll store the crtc in mtk_disp_ovl as you suggested above.

> > +       if (WARN_ON(!mtk_crtc))
> > +               return;
> 
> I think the typical thing to do if we can't handle an interrupt is to
> return IRQ_NONE, so that it can be tracked by the kernel's spurious
> interrupt infrastructure.  We can probably remove the WARN_ON, too.

Ack.

[...]
> > +       if (mtk_crtc->pending_planes) {
> > +               for (i = 0; i < OVL_LAYER_NR; i++) {
> > +                       struct drm_plane *plane = &mtk_crtc->planes[i].base;
> > +                       struct mtk_plane_state *plane_state;
> > +
> > +                       plane_state = to_mtk_plane_state(plane->state);
> > +
> > +                       if (plane_state->pending.config) {
> > +                               if (!plane_state->pending.enable)
> > +                                       mtk_ddp_comp_layer_off(ovl, i);
> > +
> > +                               mtk_ddp_comp_layer_config(ovl, i, plane_state);
> > +
> > +                               if (plane_state->pending.enable)
> > +                                       mtk_ddp_comp_layer_on(ovl, i);
> 
> .layer_off() and .layer_on() are redundant, and can just be handled inside
> .layer_config(), since we pass plane_state to .layer_config() anyway.
> 
> That will also be slightly more efficient, since the mtk_ddp_comp_layer*() will
> then all be static functions in the same file and on/off can be inlined.

Ok.

[...]
> > +static struct mtk_ddp_comp_match mtk_ddp_matches[DDP_COMPONENT_ID_MAX] = {
> 
> static const struct ...

Ok.

[...]
> > +int mtk_ddp_comp_init(struct device *dev, struct device_node *node,
> > +                     struct mtk_ddp_comp *comp, enum mtk_ddp_comp_id comp_id,
> > +                     const struct mtk_ddp_comp_funcs *funcs)
> > +{
[...]
> > +       larb_node = of_parse_phandle(node, "mediatek,larb", 0);
> 
> Need to call of_node_put() for larb_node somewhere.

Ok.

[...]
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fb.h b/drivers/gpu/drm/mediatek/mtk_drm_fb.h
> > new file mode 100644
> > index 0000000..a89c7af
> > --- /dev/null
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_fb.h
> > @@ -0,0 +1,29 @@
[...]
> > +#define MAX_FB_OBJ     3
> 
> Remove from this patch

Ok.

> > +
> > +struct drm_gem_object *mtk_fb_get_gem_obj(struct drm_framebuffer *fb);
> > +int mtk_fb_wait(struct drm_framebuffer *fb);
> > +struct drm_framebuffer *mtk_drm_mode_fb_create(struct drm_device *dev,
> > +                                              struct drm_file *file,
> > +                                              struct drm_mode_fb_cmd2 *cmd);
> > +
> > +void mtk_drm_mode_output_poll_changed(struct drm_device *dev);
> > +int mtk_fbdev_create(struct drm_device *dev);
> > +void mtk_fbdev_destroy(struct drm_device *dev);
> 
> Remove these last three function prototypes from this patch.

Ok.

[...]
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > new file mode 100644
> > index 0000000..96cc980
> > --- /dev/null
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > @@ -0,0 +1,227 @@
[...]
> > +static struct mtk_drm_gem_obj *mtk_drm_gem_init(struct drm_device *dev,
> > +                                               unsigned long size)
> 
> nit: I think these "size in bytes" parameters should use size_t.

Ok.

[...]
> > +struct mtk_drm_gem_obj *mtk_drm_gem_create(struct drm_device *dev,
> > +                                          unsigned long size, bool alloc_kmap)
> > +{
[...]
> > +       mtk_gem->cookie = dma_alloc_attrs(dev->dev, obj->size,
> > +                               (dma_addr_t *)&mtk_gem->dma_addr, GFP_KERNEL,
> 
> Cast here is not necessary, since dma_addr is dma_addr_t.

Ok.

> > +                               &mtk_gem->dma_attrs);
> > +       if (!mtk_gem->cookie) {
> > +               DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size);
> > +               ret = -ENOMEM;
> > +               goto err_gem_free;
> > +       }
> > +
> > +       if (alloc_kmap)
> > +               mtk_gem->kvaddr = mtk_gem->cookie;
> > +
> > +       DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad\n",
> > +                        mtk_gem->cookie, &mtk_gem->dma_addr);
> 
> Print size too.

Ok.

[...]
> > +int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
> > +                           struct drm_mode_create_dumb *args)
> > +{
> > +       struct mtk_drm_gem_obj *mtk_gem;
> > +       int ret;
> > +
> > +       args->pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
> 
> Perhaps this more correctly aligns the pitch (this is what cma does):
>   args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);

Ok.

[...]
> > +int mtk_drm_gem_dumb_map_offset(struct drm_file *file_priv,
> > +                               struct drm_device *dev, uint32_t handle,
> > +                               uint64_t *offset)
> > +{
> > +       struct drm_gem_object *obj;
> > +       int ret;
> > +
> 
> The cma helper locks struct_mutex here.

See commit 141518b64f61 ("drm/cma-helper: Don't grab dev->struct_mutex
for in mmap offset ioctl")

[...]
> > +/*
> > + * Allocate a sg_table for this GEM object.
> > + * Note: Both the table's contents, and the sg_table itself must be freed by
> > + *       the caller.
> > + * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
> > + */
> > +struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj)
> > +{
> > +       struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
> > +       struct drm_device *drm = obj->dev;
> > +       struct sg_table *sgt;
> > +       int ret;
> > +
> > +       sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
> > +       if (!sgt)
> > +               return ERR_PTR(-ENOMEM);
> > +
> > +       ret = dma_get_sgtable_attrs(drm->dev, sgt, mtk_gem->cookie,
> > +                                   mtk_gem->dma_addr, obj->size,
> > +                                   &mtk_gem->dma_attrs);
> > +       if (ret) {
> > +               DRM_ERROR("failed to allocate sgt, %d\n", ret);
> > +               kfree(sgt);
> > +               return ERR_PTR(ret);
> > +       }
> > +
> > +       return sgt;
> > +}
> 
> Do we also want a prime_import_sg_table() here for importing foreign allocated
> dma bufs for display?

I'll include the patch by Mao Huang next round.

[...]
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> > new file mode 100644
> > index 0000000..e9b6bf6
> > --- /dev/null
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> > @@ -0,0 +1,242 @@
[...]
> > +static void mtk_plane_enable(struct mtk_drm_plane *mtk_plane, bool enable,
> > +                            dma_addr_t addr, struct drm_rect *dest)
> > +{
[...]
> > +       state->pending.enable = enable;
> > +       state->pending.pitch = pitch;
> > +       state->pending.format = format;
> > +       state->pending.addr = addr;
> > +       state->pending.x = x;
> > +       state->pending.y = y;
> > +       state->pending.width = dest->x2 - dest->x1;
> > +       state->pending.height = dest->y2 - dest->y1;
> 
> wmb(); ?
> 
> BTW, it is a good idea to document all wmb() calls.
> If you forget, I believe checkpatch.pl will remind you.

Ok.

> That's it!

thanks
Philipp
Philipp Zabel Feb. 3, 2016, 2:31 p.m. UTC | #4
Hi Daniel,

Am Mittwoch, den 03.02.2016, 01:12 +0800 schrieb Daniel Kurtz:
[...]
> > +int mtk_drm_crtc_create(struct drm_device *drm_dev,
> > +                       const enum mtk_ddp_comp_id *path, unsigned int path_len)
> > +{
[...]
> > +       for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
> > +               enum mtk_ddp_comp_id comp_id = path[i];
> > +               struct mtk_ddp_comp *comp;

I'll check for (priv->comp_node[comp_id] != NULL) here.

> > +               comp = priv->ddp_comp[comp_id];
> > +               if (!comp) {
> > +                       dev_err(dev, "Component %s not initialized\n",
> > +                               priv->comp_node[comp_id]->full_name);
> 
> If one of the components is disabled in .dtsi, then its
> priv->comp_node[comp_id] will be NULL here, and trying to full_name will OOPS.

^^

[...]
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > new file mode 100644
> > index 0000000..9db22b4
> > --- /dev/null
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
[...]
> > +static struct drm_driver mtk_drm_driver = {
> > +       .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME |
> > +                          DRIVER_ATOMIC,
> > +       .unload = mtk_drm_unload,
> > +       .set_busid = drm_platform_set_busid,
> 
> I think using drm_platform_set_busid() as our .set_busid may cause an OOPs if
> userspace does DRM_IOCTL_SET_VERSION.
> 
> drm_setversion() will calls drm_set_busid(), which calls
> dev->driver->set_busid()
> drm_platform_set_busid() accesses dev->platformdev->id.
> 
> However, dev->platformdev is only set by:
>   drm_platform_init()->drm_get_platform_dev()
> 
> And, since mtk_drm_bind() does the drm_dev_alloc() /
> drm_dev_register() itself instead
> of calling drm_get_platform_dev(), so dev->platformdev will still be NULL.
> 
> So, why don't we call drm_platform_init() instead and implement a .load callback
> to do mtk_drm_kms_init()?

This is deprecated, I had used it that way until v4.
Can we just drop the set_busid callback?

regards
Philipp
diff mbox

Patch

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index c4bf9a1..8fdb0c2 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -266,3 +266,5 @@  source "drivers/gpu/drm/amd/amdkfd/Kconfig"
 source "drivers/gpu/drm/imx/Kconfig"
 
 source "drivers/gpu/drm/vc4/Kconfig"
+
+source "drivers/gpu/drm/mediatek/Kconfig"
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 1e9ff4c..607a49f 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -71,6 +71,7 @@  obj-$(CONFIG_DRM_MSM) += msm/
 obj-$(CONFIG_DRM_TEGRA) += tegra/
 obj-$(CONFIG_DRM_STI) += sti/
 obj-$(CONFIG_DRM_IMX) += imx/
+obj-$(CONFIG_DRM_MEDIATEK) += mediatek/
 obj-y			+= i2c/
 obj-y			+= panel/
 obj-y			+= bridge/
diff --git a/drivers/gpu/drm/mediatek/Kconfig b/drivers/gpu/drm/mediatek/Kconfig
new file mode 100644
index 0000000..8dad892
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/Kconfig
@@ -0,0 +1,12 @@ 
+config DRM_MEDIATEK
+	tristate "DRM Support for Mediatek SoCs"
+	depends on DRM
+	depends on ARCH_MEDIATEK || (ARM && COMPILE_TEST)
+	select DRM_KMS_HELPER
+	select IOMMU_DMA
+	select MTK_SMI
+	help
+	  Choose this option if you have a Mediatek SoCs.
+	  The module will be called mediatek-drm
+	  This driver provides kernel mode setting and
+	  buffer management to userspace.
diff --git a/drivers/gpu/drm/mediatek/Makefile b/drivers/gpu/drm/mediatek/Makefile
new file mode 100644
index 0000000..c7cc41a
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/Makefile
@@ -0,0 +1,10 @@ 
+mediatek-drm-y := mtk_disp_ovl.o \
+		  mtk_drm_crtc.o \
+		  mtk_drm_ddp.o \
+		  mtk_drm_ddp_comp.o \
+		  mtk_drm_drv.o \
+		  mtk_drm_fb.o \
+		  mtk_drm_gem.o \
+		  mtk_drm_plane.o
+
+obj-$(CONFIG_DRM_MEDIATEK) += mediatek-drm.o
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
new file mode 100644
index 0000000..455e62e
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
@@ -0,0 +1,301 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <drm/drmP.h>
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+
+#include "mtk_drm_crtc.h"
+#include "mtk_drm_ddp_comp.h"
+
+#define DISP_REG_OVL_INTEN			0x0004
+#define OVL_FME_CPL_INT					BIT(1)
+#define DISP_REG_OVL_INTSTA			0x0008
+#define DISP_REG_OVL_EN				0x000c
+#define DISP_REG_OVL_RST			0x0014
+#define DISP_REG_OVL_ROI_SIZE			0x0020
+#define DISP_REG_OVL_ROI_BGCLR			0x0028
+#define DISP_REG_OVL_SRC_CON			0x002c
+#define DISP_REG_OVL_CON(n)			(0x0030 + 0x20 * (n))
+#define DISP_REG_OVL_SRC_SIZE(n)		(0x0038 + 0x20 * (n))
+#define DISP_REG_OVL_OFFSET(n)			(0x003c + 0x20 * (n))
+#define DISP_REG_OVL_PITCH(n)			(0x0044 + 0x20 * (n))
+#define DISP_REG_OVL_RDMA_CTRL(n)		(0x00c0 + 0x20 * (n))
+#define DISP_REG_OVL_RDMA_GMC(n)		(0x00c8 + 0x20 * (n))
+#define DISP_REG_OVL_ADDR(n)			(0x0f40 + 0x20 * (n))
+
+enum OVL_INPUT_FORMAT {
+	OVL_INFMT_RGB565 = 0,
+	OVL_INFMT_RGB888 = 1,
+	OVL_INFMT_RGBA8888 = 2,
+	OVL_INFMT_ARGB8888 = 3,
+};
+
+#define	OVL_RDMA_MEM_GMC	0x40402020
+#define	OVL_AEN			BIT(8)
+#define	OVL_ALPHA		0xff
+
+/**
+ * struct mtk_disp_ovl - DISP_OVL driver structure
+ * @ddp_comp - structure containing type enum and hardware resources
+ * @drm_device - backlink to allow the irq handler to find the associated crtc
+ */
+struct mtk_disp_ovl {
+	struct mtk_ddp_comp		ddp_comp;
+	struct drm_device		*drm_dev;
+};
+
+static irqreturn_t mtk_disp_ovl_irq_handler(int irq, void *dev_id)
+{
+	struct mtk_disp_ovl *priv = dev_id;
+	struct mtk_ddp_comp *ovl = &priv->ddp_comp;
+
+	/* Clear frame completion interrupt */
+	writel(0x0, ovl->regs + DISP_REG_OVL_INTSTA);
+
+	mtk_crtc_ddp_irq(priv->drm_dev, ovl);
+
+	return IRQ_HANDLED;
+}
+
+static void mtk_ovl_enable_vblank(struct mtk_ddp_comp *comp)
+{
+	writel_relaxed(OVL_FME_CPL_INT, comp->regs + DISP_REG_OVL_INTEN);
+}
+
+static void mtk_ovl_disable_vblank(struct mtk_ddp_comp *comp)
+{
+	writel_relaxed(0x0, comp->regs + DISP_REG_OVL_INTEN);
+}
+
+static void mtk_ovl_start(struct mtk_ddp_comp *comp)
+{
+	writel_relaxed(0x1, comp->regs + DISP_REG_OVL_EN);
+}
+
+static void mtk_ovl_stop(struct mtk_ddp_comp *comp)
+{
+	writel_relaxed(0x0, comp->regs + DISP_REG_OVL_EN);
+}
+
+static void mtk_ovl_config(struct mtk_ddp_comp *comp, unsigned int w,
+			   unsigned int h, unsigned int vrefresh)
+{
+	if (w != 0 && h != 0)
+		writel_relaxed(h << 16 | w, comp->regs + DISP_REG_OVL_ROI_SIZE);
+	writel_relaxed(0x0, comp->regs + DISP_REG_OVL_ROI_BGCLR);
+
+	writel(0x1, comp->regs + DISP_REG_OVL_RST);
+	writel(0x0, comp->regs + DISP_REG_OVL_RST);
+}
+
+static bool has_rb_swapped(unsigned int fmt)
+{
+	switch (fmt) {
+	case DRM_FORMAT_BGR888:
+	case DRM_FORMAT_BGR565:
+	case DRM_FORMAT_ABGR8888:
+	case DRM_FORMAT_XBGR8888:
+	case DRM_FORMAT_BGRA8888:
+	case DRM_FORMAT_BGRX8888:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static unsigned int ovl_fmt_convert(unsigned int fmt)
+{
+	switch (fmt) {
+	case DRM_FORMAT_RGB888:
+	case DRM_FORMAT_BGR888:
+		return OVL_INFMT_RGB888;
+	case DRM_FORMAT_RGB565:
+	case DRM_FORMAT_BGR565:
+		return OVL_INFMT_RGB565;
+	case DRM_FORMAT_RGBX8888:
+	case DRM_FORMAT_RGBA8888:
+	case DRM_FORMAT_BGRX8888:
+	case DRM_FORMAT_BGRA8888:
+		return OVL_INFMT_ARGB8888;
+	case DRM_FORMAT_XRGB8888:
+	case DRM_FORMAT_ARGB8888:
+	case DRM_FORMAT_XBGR8888:
+	case DRM_FORMAT_ABGR8888:
+		return OVL_INFMT_RGBA8888;
+	default:
+		DRM_ERROR("unsupported format[%08x]\n", fmt);
+		return OVL_INFMT_RGB888;
+	}
+}
+
+static void mtk_ovl_layer_on(struct mtk_ddp_comp *comp, unsigned int idx)
+{
+	unsigned int reg;
+
+	writel(0x1, comp->regs + DISP_REG_OVL_RDMA_CTRL(idx));
+	writel(OVL_RDMA_MEM_GMC, comp->regs + DISP_REG_OVL_RDMA_GMC(idx));
+
+	reg = readl(comp->regs + DISP_REG_OVL_SRC_CON);
+	reg = reg | BIT(idx);
+	writel(reg, comp->regs + DISP_REG_OVL_SRC_CON);
+}
+
+static void mtk_ovl_layer_off(struct mtk_ddp_comp *comp, unsigned int idx)
+{
+	unsigned int reg;
+
+	reg = readl(comp->regs + DISP_REG_OVL_SRC_CON);
+	reg = reg & ~BIT(idx);
+	writel(reg, comp->regs + DISP_REG_OVL_SRC_CON);
+
+	writel(0x0, comp->regs + DISP_REG_OVL_RDMA_CTRL(idx));
+}
+
+static void mtk_ovl_layer_config(struct mtk_ddp_comp *comp, unsigned int idx,
+		struct mtk_plane_state *state)
+{
+	struct mtk_plane_pending_state *pending = &state->pending;
+	unsigned int addr = pending->addr;
+	unsigned int pitch = pending->pitch & 0xffff;
+	unsigned int fmt = pending->format;
+	unsigned int offset = (pending->y << 16) | pending->x;
+	unsigned int src_size = (pending->height << 16) | pending->width;
+	unsigned int con;
+
+	con = has_rb_swapped(fmt) << 24 | ovl_fmt_convert(fmt) << 12;
+	if (idx != 0)
+		con |= OVL_AEN | OVL_ALPHA;
+
+	writel(con, comp->regs + DISP_REG_OVL_CON(idx));
+	writel(pitch, comp->regs + DISP_REG_OVL_PITCH(idx));
+	writel(src_size, comp->regs + DISP_REG_OVL_SRC_SIZE(idx));
+	writel(offset, comp->regs + DISP_REG_OVL_OFFSET(idx));
+	writel(addr, comp->regs + DISP_REG_OVL_ADDR(idx));
+}
+
+static const struct mtk_ddp_comp_funcs mtk_disp_ovl_funcs = {
+	.config = mtk_ovl_config,
+	.start = mtk_ovl_start,
+	.stop = mtk_ovl_stop,
+	.enable_vblank = mtk_ovl_enable_vblank,
+	.disable_vblank = mtk_ovl_disable_vblank,
+	.layer_on = mtk_ovl_layer_on,
+	.layer_off = mtk_ovl_layer_off,
+	.layer_config = mtk_ovl_layer_config,
+};
+
+static int mtk_disp_ovl_bind(struct device *dev, struct device *master,
+		void *data)
+{
+	struct mtk_disp_ovl *priv = dev_get_drvdata(dev);
+	struct drm_device *drm_dev = data;
+	int ret;
+
+	priv->drm_dev = drm_dev;
+
+	ret = mtk_ddp_comp_register(drm_dev, &priv->ddp_comp);
+	if (ret < 0) {
+		dev_err(dev, "Failed to register component %s: %d\n",
+			dev->of_node->full_name, ret);
+		return ret;
+	}
+
+	return 0;
+
+}
+
+static void mtk_disp_ovl_unbind(struct device *dev, struct device *master,
+		void *data)
+{
+	struct mtk_disp_ovl *priv = dev_get_drvdata(dev);
+	struct drm_device *drm_dev = data;
+
+	mtk_ddp_comp_unregister(drm_dev, &priv->ddp_comp);
+}
+
+static const struct component_ops mtk_disp_ovl_component_ops = {
+	.bind	= mtk_disp_ovl_bind,
+	.unbind = mtk_disp_ovl_unbind,
+};
+
+static int mtk_disp_ovl_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mtk_disp_ovl *priv;
+	int comp_id;
+	int irq;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	ret = devm_request_irq(dev, irq, mtk_disp_ovl_irq_handler,
+			       IRQF_TRIGGER_NONE, dev_name(dev), priv);
+	if (ret < 0) {
+		dev_err(dev, "Failed to request irq %d: %d\n", irq, ret);
+		return ret;
+	}
+
+	comp_id = mtk_ddp_comp_get_id(dev->of_node, MTK_DISP_OVL);
+	if (comp_id < 0) {
+		dev_err(dev, "Failed to identify by alias: %d\n", comp_id);
+		return comp_id;
+	}
+
+	ret = mtk_ddp_comp_init(dev, dev->of_node, &priv->ddp_comp, comp_id,
+				&mtk_disp_ovl_funcs);
+	if (ret) {
+		dev_err(dev, "Failed to initialize component: %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	ret = component_add(dev, &mtk_disp_ovl_component_ops);
+	if (ret)
+		dev_err(dev, "Failed to add component: %d\n", ret);
+
+	return ret;
+}
+
+static int mtk_disp_ovl_remove(struct platform_device *pdev)
+{
+	component_del(&pdev->dev, &mtk_disp_ovl_component_ops);
+
+	return 0;
+}
+
+static const struct of_device_id mtk_disp_ovl_driver_dt_match[] = {
+	{ .compatible = "mediatek,mt8173-disp-ovl", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mtk_disp_ovl_driver_dt_match);
+
+struct platform_driver mtk_disp_ovl_driver = {
+	.probe		= mtk_disp_ovl_probe,
+	.remove		= mtk_disp_ovl_remove,
+	.driver		= {
+		.name	= "mediatek-disp-ovl",
+		.owner	= THIS_MODULE,
+		.of_match_table = mtk_disp_ovl_driver_dt_match,
+	},
+};
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
new file mode 100644
index 0000000..42f6e54
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -0,0 +1,603 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <asm/barrier.h>
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_plane_helper.h>
+#include <linux/clk.h>
+#include <linux/pm_runtime.h>
+#include <soc/mediatek/smi.h>
+
+#include "mtk_drm_drv.h"
+#include "mtk_drm_crtc.h"
+#include "mtk_drm_ddp.h"
+#include "mtk_drm_ddp_comp.h"
+#include "mtk_drm_gem.h"
+#include "mtk_drm_plane.h"
+
+/**
+ * struct mtk_drm_crtc - MediaTek specific crtc structure.
+ * @base: crtc object.
+ * @enabled: records whether crtc_enable succeeded
+ * @do_flush: enabled by atomic_flush, causes plane atomic_update to commit
+ *            changed state immediately.
+ * @planes: array of 4 mtk_drm_plane structures, one for each overlay plane
+ * @pending_planes: whether any plane has pending changes to be applied
+ * @config_regs: memory mapped mmsys configuration register space
+ * @mutex: handle to one of the ten disp_mutex streams
+ * @ddp_comp_nr: number of components in ddp_comp
+ * @ddp_comp: array of pointers the mtk_ddp_comp structures used by this crtc
+ */
+struct mtk_drm_crtc {
+	struct drm_crtc			base;
+	bool				enabled;
+
+	bool				do_flush;
+	bool				pending_needs_vblank;
+	struct drm_pending_vblank_event	*event;
+
+	struct mtk_drm_plane		planes[OVL_LAYER_NR];
+	bool				pending_planes;
+
+	void __iomem			*config_regs;
+	struct mtk_disp_mutex		*mutex;
+	unsigned int			ddp_comp_nr;
+	struct mtk_ddp_comp		**ddp_comp;
+};
+
+struct mtk_crtc_state {
+	struct drm_crtc_state		base;
+
+	bool				pending_config;
+	unsigned int			pending_width;
+	unsigned int			pending_height;
+	unsigned int			pending_vrefresh;
+};
+
+static inline struct mtk_drm_crtc *to_mtk_crtc(struct drm_crtc *c)
+{
+	return container_of(c, struct mtk_drm_crtc, base);
+}
+
+static inline struct mtk_crtc_state *to_mtk_crtc_state(struct drm_crtc_state *s)
+{
+	return container_of(s, struct mtk_crtc_state, base);
+}
+
+/*
+ * Given a DDP source component (OVL or RDMA), find the crtc that has this
+ * component as first element of its ddp_comp array. This allows to deliver
+ * the source component's end of frame interrupt to the corresponding crtc.
+ */
+static struct mtk_drm_crtc *mtk_crtc_by_src_comp(struct mtk_drm_private *priv,
+						 struct mtk_ddp_comp *ddp_comp)
+{
+	struct mtk_drm_crtc *mtk_crtc;
+	int i;
+
+	for (i = 0; i < MAX_CRTC; i++) {
+		mtk_crtc = to_mtk_crtc(priv->crtc[i]);
+		if (mtk_crtc->ddp_comp[0] == ddp_comp)
+			return mtk_crtc;
+	}
+
+	return NULL;
+}
+
+static void mtk_drm_crtc_finish_page_flip(struct mtk_drm_crtc *mtk_crtc)
+{
+	struct drm_crtc *crtc = &mtk_crtc->base;
+	unsigned long flags;
+
+	spin_lock_irqsave(&crtc->dev->event_lock, flags);
+	drm_send_vblank_event(crtc->dev, mtk_crtc->event->pipe, mtk_crtc->event);
+	drm_crtc_vblank_put(crtc);
+	mtk_crtc->event = NULL;
+	spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
+}
+
+static void mtk_drm_finish_page_flip(struct mtk_drm_crtc *mtk_crtc)
+{
+	drm_crtc_handle_vblank(&mtk_crtc->base);
+	if (mtk_crtc->pending_needs_vblank) {
+		mtk_drm_crtc_finish_page_flip(mtk_crtc);
+		mtk_crtc->pending_needs_vblank = false;
+	}
+}
+
+static void mtk_drm_crtc_destroy(struct drm_crtc *crtc)
+{
+	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+	int i;
+
+	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
+		clk_unprepare(mtk_crtc->ddp_comp[i]->clk);
+
+	mtk_disp_mutex_put(mtk_crtc->mutex);
+
+	drm_crtc_cleanup(crtc);
+}
+
+static void mtk_drm_crtc_reset(struct drm_crtc *crtc)
+{
+	struct mtk_crtc_state *state;
+
+	if (crtc->state) {
+		if (crtc->state->mode_blob)
+			drm_property_unreference_blob(crtc->state->mode_blob);
+
+		state = to_mtk_crtc_state(crtc->state);
+		memset(state, 0, sizeof(*state));
+	} else {
+		state = kzalloc(sizeof(*state), GFP_KERNEL);
+		if (!state)
+			return;
+		crtc->state = &state->base;
+	}
+
+	state->base.crtc = crtc;
+}
+
+static struct drm_crtc_state *mtk_drm_crtc_duplicate_state(struct drm_crtc *crtc)
+{
+	struct mtk_crtc_state *state;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return NULL;
+
+	__drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
+
+	WARN_ON(state->base.crtc != crtc);
+	state->base.crtc = crtc;
+
+	return &state->base;
+}
+
+static void mtk_drm_crtc_destroy_state(struct drm_crtc *crtc,
+				       struct drm_crtc_state *state)
+{
+	__drm_atomic_helper_crtc_destroy_state(crtc, state);
+	kfree(to_mtk_crtc_state(state));
+}
+
+static bool mtk_drm_crtc_mode_fixup(struct drm_crtc *crtc,
+		const struct drm_display_mode *mode,
+		struct drm_display_mode *adjusted_mode)
+{
+	/* Nothing to do here, but this callback is mandatory. */
+	return true;
+}
+
+static void mtk_drm_crtc_mode_set_nofb(struct drm_crtc *crtc)
+{
+	struct mtk_crtc_state *state = to_mtk_crtc_state(crtc->state);
+
+	state->pending_width = crtc->mode.hdisplay;
+	state->pending_height = crtc->mode.vdisplay;
+	state->pending_vrefresh = crtc->mode.vrefresh;
+	wmb();	/* Make sure the above parameters are set before update */
+	state->pending_config = true;
+}
+
+int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe)
+{
+	struct mtk_drm_private *priv = drm->dev_private;
+	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(priv->crtc[pipe]);
+	struct mtk_ddp_comp *ovl = mtk_crtc->ddp_comp[0];
+
+	mtk_ddp_comp_enable_vblank(ovl);
+
+	return 0;
+}
+
+void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int pipe)
+{
+	struct mtk_drm_private *priv = drm->dev_private;
+	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(priv->crtc[pipe]);
+	struct mtk_ddp_comp *ovl = mtk_crtc->ddp_comp[0];
+
+	mtk_ddp_comp_disable_vblank(ovl);
+}
+
+static int mtk_crtc_ddp_clk_enable(struct mtk_drm_crtc *mtk_crtc)
+{
+	int ret;
+	int i;
+
+	DRM_DEBUG_DRIVER("%s\n", __func__);
+	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
+		ret = clk_enable(mtk_crtc->ddp_comp[i]->clk);
+		if (ret) {
+			DRM_ERROR("Failed to enable clock %d: %d\n", i, ret);
+			goto err;
+		}
+	}
+
+	return 0;
+err:
+	while (--i >= 0)
+		clk_disable(mtk_crtc->ddp_comp[i]->clk);
+	return ret;
+}
+
+static void mtk_crtc_ddp_clk_disable(struct mtk_drm_crtc *mtk_crtc)
+{
+	int i;
+
+	DRM_DEBUG_DRIVER("%s\n", __func__);
+	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
+		clk_disable(mtk_crtc->ddp_comp[i]->clk);
+}
+
+static int mtk_crtc_ddp_hw_init(struct mtk_drm_crtc *mtk_crtc)
+{
+	struct drm_crtc *crtc = &mtk_crtc->base;
+	unsigned int width, height, vrefresh;
+	int ret;
+	int i;
+
+	DRM_DEBUG_DRIVER("%s\n", __func__);
+	if (WARN_ON(!crtc->state))
+		return -EINVAL;
+
+	width = crtc->state->adjusted_mode.hdisplay;
+	height = crtc->state->adjusted_mode.vdisplay;
+	vrefresh = crtc->state->adjusted_mode.vrefresh;
+
+	ret = pm_runtime_get_sync(crtc->dev->dev);
+	if (ret < 0) {
+		DRM_ERROR("Failed to enable power domain: %d\n", ret);
+		return ret;
+	}
+
+	ret = mtk_disp_mutex_prepare(mtk_crtc->mutex);
+	if (ret < 0) {
+		DRM_ERROR("Failed to enable mutex clock: %d\n", ret);
+		goto err_pm_runtime_put;
+	}
+
+	ret = mtk_crtc_ddp_clk_enable(mtk_crtc);
+	if (ret < 0) {
+		DRM_ERROR("Failed to enable component clocks: %d\n", ret);
+		goto err_mutex_unprepare;
+	}
+
+	DRM_DEBUG_DRIVER("mediatek_ddp_ddp_path_setup\n");
+	for (i = 0; i < mtk_crtc->ddp_comp_nr - 1; i++) {
+		mtk_ddp_add_comp_to_path(mtk_crtc->config_regs,
+					 mtk_crtc->ddp_comp[i]->id,
+					 mtk_crtc->ddp_comp[i + 1]->id);
+		mtk_disp_mutex_add_comp(mtk_crtc->mutex,
+					mtk_crtc->ddp_comp[i]->id);
+	}
+	mtk_disp_mutex_add_comp(mtk_crtc->mutex, mtk_crtc->ddp_comp[i]->id);
+	mtk_disp_mutex_enable(mtk_crtc->mutex);
+
+	DRM_DEBUG_DRIVER("ddp_disp_path_power_on %dx%d\n", width, height);
+	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
+		struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[i];
+
+		mtk_ddp_comp_config(comp, width, height, vrefresh);
+		mtk_ddp_comp_start(comp);
+	}
+
+	return 0;
+
+err_mutex_unprepare:
+	mtk_disp_mutex_unprepare(mtk_crtc->mutex);
+err_pm_runtime_put:
+	pm_runtime_put(crtc->dev->dev);
+	return ret;
+}
+
+static void mtk_crtc_ddp_hw_fini(struct mtk_drm_crtc *mtk_crtc)
+{
+	struct drm_device *drm = mtk_crtc->base.dev;
+	int i;
+
+	DRM_DEBUG_DRIVER("%s\n", __func__);
+	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
+		mtk_ddp_comp_stop(mtk_crtc->ddp_comp[i]);
+	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
+		mtk_disp_mutex_remove_comp(mtk_crtc->mutex,
+					   mtk_crtc->ddp_comp[i]->id);
+	mtk_disp_mutex_disable(mtk_crtc->mutex);
+	for (i = 0; i < mtk_crtc->ddp_comp_nr - 1; i++) {
+		mtk_ddp_remove_comp_from_path(mtk_crtc->config_regs,
+					      mtk_crtc->ddp_comp[i]->id,
+					      mtk_crtc->ddp_comp[i + 1]->id);
+		mtk_disp_mutex_remove_comp(mtk_crtc->mutex,
+					   mtk_crtc->ddp_comp[i]->id);
+	}
+	mtk_disp_mutex_remove_comp(mtk_crtc->mutex, mtk_crtc->ddp_comp[i]->id);
+	mtk_crtc_ddp_clk_disable(mtk_crtc);
+	mtk_disp_mutex_unprepare(mtk_crtc->mutex);
+
+	pm_runtime_put(drm->dev);
+}
+
+static void mtk_drm_crtc_enable(struct drm_crtc *crtc)
+{
+	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+	struct mtk_ddp_comp *ovl = mtk_crtc->ddp_comp[0];
+	int ret;
+
+	DRM_DEBUG_DRIVER("%s %d\n", __func__, crtc->base.id);
+
+	ret = mtk_smi_larb_get(ovl->larb_dev);
+	if (ret) {
+		DRM_ERROR("Failed to get larb: %d\n", ret);
+		return;
+	}
+
+	ret = mtk_crtc_ddp_hw_init(mtk_crtc);
+	if (ret) {
+		mtk_smi_larb_put(ovl->larb_dev);
+		return;
+	}
+
+	drm_crtc_vblank_on(crtc);
+	mtk_crtc->enabled = true;
+}
+
+static void mtk_drm_crtc_disable(struct drm_crtc *crtc)
+{
+	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+	struct mtk_ddp_comp *ovl = mtk_crtc->ddp_comp[0];
+	int i;
+
+	DRM_DEBUG_DRIVER("%s %d\n", __func__, crtc->base.id);
+	if (WARN_ON(!mtk_crtc->enabled))
+		return;
+
+	/* Set all pending plane state to disabled */
+	for (i = 0; i < OVL_LAYER_NR; i++) {
+		struct drm_plane *plane = &mtk_crtc->planes[i].base;
+		struct mtk_plane_state *plane_state;
+
+		plane_state = to_mtk_plane_state(plane->state);
+		plane_state->pending.enable = false;
+		plane_state->pending.config = true;
+	}
+	mtk_crtc->pending_planes = true;
+
+	/* Wait for planes to be disabled */
+	drm_crtc_wait_one_vblank(crtc);
+
+	drm_crtc_vblank_off(crtc);
+	mtk_crtc_ddp_hw_fini(mtk_crtc);
+	mtk_smi_larb_put(ovl->larb_dev);
+
+	mtk_crtc->do_flush = false;
+	mtk_crtc->enabled = false;
+}
+
+static void mtk_drm_crtc_atomic_begin(struct drm_crtc *crtc,
+				      struct drm_crtc_state *old_crtc_state)
+{
+	struct mtk_crtc_state *state = to_mtk_crtc_state(crtc->state);
+	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+
+	if (mtk_crtc->event && state->base.event)
+		DRM_ERROR("new event while there is still a pending event\n");
+
+	if (state->base.event) {
+		state->base.event->pipe = drm_crtc_index(crtc);
+		WARN_ON(drm_crtc_vblank_get(crtc) != 0);
+		mtk_crtc->event = state->base.event;
+		state->base.event = NULL;
+	}
+}
+
+void mtk_drm_crtc_check_flush(struct drm_crtc *crtc)
+{
+	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+	int i;
+
+	if (mtk_crtc->do_flush) {
+		if (mtk_crtc->event)
+			mtk_crtc->pending_needs_vblank = true;
+		for (i = 0; i < OVL_LAYER_NR; i++) {
+			struct drm_plane *plane = &mtk_crtc->planes[i].base;
+			struct mtk_plane_state *plane_state;
+
+			plane_state = to_mtk_plane_state(plane->state);
+			if (plane_state->pending.dirty) {
+				plane_state->pending.config = true;
+				plane_state->pending.dirty = false;
+			}
+		}
+		mtk_crtc->pending_planes = true;
+		mtk_crtc->do_flush = false;
+	}
+}
+
+static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc,
+				      struct drm_crtc_state *old_crtc_state)
+{
+	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+
+	mtk_crtc->do_flush = true;
+	mtk_drm_crtc_check_flush(crtc);
+}
+
+static const struct drm_crtc_funcs mtk_crtc_funcs = {
+	.set_config		= drm_atomic_helper_set_config,
+	.page_flip		= drm_atomic_helper_page_flip,
+	.destroy		= mtk_drm_crtc_destroy,
+	.reset			= mtk_drm_crtc_reset,
+	.atomic_duplicate_state	= mtk_drm_crtc_duplicate_state,
+	.atomic_destroy_state	= mtk_drm_crtc_destroy_state,
+};
+
+static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
+	.mode_fixup	= mtk_drm_crtc_mode_fixup,
+	.mode_set_nofb	= mtk_drm_crtc_mode_set_nofb,
+	.enable		= mtk_drm_crtc_enable,
+	.disable	= mtk_drm_crtc_disable,
+	.atomic_begin	= mtk_drm_crtc_atomic_begin,
+	.atomic_flush	= mtk_drm_crtc_atomic_flush,
+};
+
+static int mtk_drm_crtc_init(struct drm_device *drm,
+		struct mtk_drm_crtc *mtk_crtc, struct drm_plane *primary,
+		struct drm_plane *cursor, unsigned int pipe)
+{
+	int ret;
+
+	ret = drm_crtc_init_with_planes(drm, &mtk_crtc->base, primary, cursor,
+			&mtk_crtc_funcs);
+	if (ret)
+		goto err_cleanup_crtc;
+
+	drm_crtc_helper_add(&mtk_crtc->base, &mtk_crtc_helper_funcs);
+
+	return 0;
+
+err_cleanup_crtc:
+	drm_crtc_cleanup(&mtk_crtc->base);
+	return ret;
+}
+
+void mtk_crtc_ddp_irq(struct drm_device *drm_dev, struct mtk_ddp_comp *ovl)
+{
+	struct mtk_drm_private *priv = drm_dev->dev_private;
+	struct mtk_drm_crtc *mtk_crtc;
+	struct mtk_crtc_state *state;
+	unsigned int i;
+
+	mtk_crtc = mtk_crtc_by_src_comp(priv, ovl);
+	if (WARN_ON(!mtk_crtc))
+		return;
+
+	state = to_mtk_crtc_state(mtk_crtc->base.state);
+
+	/*
+	 * TODO: instead of updating the registers here, we should prepare
+	 * working registers in atomic_commit and let the hardware command
+	 * queue update module registers on vblank.
+	 */
+	if (state->pending_config) {
+		mtk_ddp_comp_config(ovl, state->pending_width,
+				    state->pending_height,
+				    state->pending_vrefresh);
+
+		state->pending_config = false;
+	}
+
+	if (mtk_crtc->pending_planes) {
+		for (i = 0; i < OVL_LAYER_NR; i++) {
+			struct drm_plane *plane = &mtk_crtc->planes[i].base;
+			struct mtk_plane_state *plane_state;
+
+			plane_state = to_mtk_plane_state(plane->state);
+
+			if (plane_state->pending.config) {
+				if (!plane_state->pending.enable)
+					mtk_ddp_comp_layer_off(ovl, i);
+
+				mtk_ddp_comp_layer_config(ovl, i, plane_state);
+
+				if (plane_state->pending.enable)
+					mtk_ddp_comp_layer_on(ovl, i);
+
+				plane_state->pending.config = false;
+			}
+		}
+		mtk_crtc->pending_planes = false;
+	}
+
+	mtk_drm_finish_page_flip(mtk_crtc);
+}
+
+int mtk_drm_crtc_create(struct drm_device *drm_dev,
+			const enum mtk_ddp_comp_id *path, unsigned int path_len)
+{
+	struct mtk_drm_private *priv = drm_dev->dev_private;
+	struct device *dev = drm_dev->dev;
+	struct mtk_drm_crtc *mtk_crtc;
+	enum drm_plane_type type;
+	unsigned int zpos;
+	int pipe = priv->num_pipes;
+	int ret;
+	int i;
+
+	mtk_crtc = devm_kzalloc(dev, sizeof(*mtk_crtc), GFP_KERNEL);
+	if (!mtk_crtc)
+		return -ENOMEM;
+
+	mtk_crtc->config_regs = priv->config_regs;
+	mtk_crtc->ddp_comp_nr = path_len;
+	mtk_crtc->ddp_comp = devm_kmalloc_array(dev, mtk_crtc->ddp_comp_nr,
+						sizeof(*mtk_crtc->ddp_comp),
+						GFP_KERNEL);
+
+	mtk_crtc->mutex = mtk_disp_mutex_get(priv->mutex_dev, pipe);
+	if (IS_ERR(mtk_crtc->mutex)) {
+		ret = PTR_ERR(mtk_crtc->mutex);
+		dev_err(dev, "Failed to get mutex: %d\n", ret);
+		return ret;
+	}
+
+	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
+		enum mtk_ddp_comp_id comp_id = path[i];
+		struct mtk_ddp_comp *comp;
+
+		comp = priv->ddp_comp[comp_id];
+		if (!comp) {
+			dev_err(dev, "Component %s not initialized\n",
+				priv->comp_node[comp_id]->full_name);
+			ret = -ENODEV;
+			goto unprepare;
+		}
+
+		ret = clk_prepare(comp->clk);
+		if (ret) {
+			dev_err(dev,
+				"Failed to prepare clock for component %s: %d\n",
+				priv->comp_node[comp_id]->full_name, ret);
+			goto unprepare;
+		}
+
+		mtk_crtc->ddp_comp[i] = comp;
+	}
+
+	for (zpos = 0; zpos < OVL_LAYER_NR; zpos++) {
+		type = (zpos == 0) ? DRM_PLANE_TYPE_PRIMARY :
+				(zpos == 1) ? DRM_PLANE_TYPE_CURSOR :
+						DRM_PLANE_TYPE_OVERLAY;
+		ret = mtk_plane_init(drm_dev, &mtk_crtc->planes[zpos],
+				     BIT(pipe), type, zpos);
+		if (ret)
+			goto unprepare;
+	}
+
+	ret = mtk_drm_crtc_init(drm_dev, mtk_crtc, &mtk_crtc->planes[0].base,
+				&mtk_crtc->planes[1].base, pipe);
+	if (ret < 0)
+		goto unprepare;
+
+	priv->crtc[pipe] = &mtk_crtc->base;
+	priv->num_pipes++;
+
+	return 0;
+
+unprepare:
+	while (--i >= 0)
+		clk_unprepare(mtk_crtc->ddp_comp[i]->clk);
+
+	return ret;
+}
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
new file mode 100644
index 0000000..94eba3c
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
@@ -0,0 +1,32 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef MTK_DRM_CRTC_H
+#define MTK_DRM_CRTC_H
+
+#include <drm/drm_crtc.h>
+#include "mtk_drm_ddp_comp.h"
+#include "mtk_drm_plane.h"
+
+#define OVL_LAYER_NR	4
+
+int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe);
+void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int pipe);
+void mtk_drm_crtc_check_flush(struct drm_crtc *crtc);
+void mtk_drm_crtc_commit(struct drm_crtc *crtc);
+void mtk_crtc_ddp_irq(struct drm_device *drm_dev, struct mtk_ddp_comp *ovl);
+int mtk_drm_crtc_create(struct drm_device *drm_dev,
+			const enum mtk_ddp_comp_id *path,
+			unsigned int path_len);
+
+#endif /* MTK_DRM_CRTC_H */
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp.c
new file mode 100644
index 0000000..16584e4
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp.c
@@ -0,0 +1,355 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include "mtk_drm_ddp.h"
+#include "mtk_drm_ddp_comp.h"
+
+#define DISP_REG_CONFIG_DISP_OVL0_MOUT_EN	0x040
+#define DISP_REG_CONFIG_DISP_OVL1_MOUT_EN	0x044
+#define DISP_REG_CONFIG_DISP_OD_MOUT_EN		0x048
+#define DISP_REG_CONFIG_DISP_GAMMA_MOUT_EN	0x04c
+#define DISP_REG_CONFIG_DISP_UFOE_MOUT_EN	0x050
+#define DISP_REG_CONFIG_DISP_COLOR0_SEL_IN	0x084
+#define DISP_REG_CONFIG_DISP_COLOR1_SEL_IN	0x088
+#define DISP_REG_CONFIG_DPI_SEL_IN		0x0ac
+#define DISP_REG_CONFIG_DISP_RDMA1_MOUT_EN	0x0c8
+#define DISP_REG_CONFIG_MMSYS_CG_CON0		0x100
+
+#define DISP_REG_MUTEX_EN(n)	(0x20 + 0x20 * (n))
+#define DISP_REG_MUTEX_RST(n)	(0x28 + 0x20 * (n))
+#define DISP_REG_MUTEX_MOD(n)	(0x2c + 0x20 * (n))
+#define DISP_REG_MUTEX_SOF(n)	(0x30 + 0x20 * (n))
+
+#define MUTEX_MOD_DISP_OVL0		BIT(11)
+#define MUTEX_MOD_DISP_OVL1		BIT(12)
+#define MUTEX_MOD_DISP_RDMA0		BIT(13)
+#define MUTEX_MOD_DISP_RDMA1		BIT(14)
+#define MUTEX_MOD_DISP_RDMA2		BIT(15)
+#define MUTEX_MOD_DISP_WDMA0		BIT(16)
+#define MUTEX_MOD_DISP_WDMA1		BIT(17)
+#define MUTEX_MOD_DISP_COLOR0		BIT(18)
+#define MUTEX_MOD_DISP_COLOR1		BIT(19)
+#define MUTEX_MOD_DISP_AAL		BIT(20)
+#define MUTEX_MOD_DISP_GAMMA		BIT(21)
+#define MUTEX_MOD_DISP_UFOE		BIT(22)
+#define MUTEX_MOD_DISP_PWM0		BIT(23)
+#define MUTEX_MOD_DISP_PWM1		BIT(24)
+#define MUTEX_MOD_DISP_OD		BIT(25)
+
+#define MUTEX_SOF_SINGLE_MODE		0
+#define MUTEX_SOF_DSI0			1
+#define MUTEX_SOF_DSI1			2
+#define MUTEX_SOF_DPI0			3
+
+#define OVL0_MOUT_EN_COLOR0		0x1
+#define OD_MOUT_EN_RDMA0		0x1
+#define UFOE_MOUT_EN_DSI0		0x1
+#define COLOR0_SEL_IN_OVL0		0x1
+#define OVL1_MOUT_EN_COLOR1		0x1
+#define GAMMA_MOUT_EN_RDMA1		0x1
+#define RDMA1_MOUT_DPI0			0x2
+#define DPI0_SEL_IN_RDMA1		0x1
+#define COLOR1_SEL_IN_OVL1		0x1
+
+struct mtk_disp_mutex {
+	int id;
+	bool claimed;
+};
+
+struct mtk_ddp {
+	struct device			*dev;
+	struct clk			*clk;
+	void __iomem			*regs;
+	struct mtk_disp_mutex		mutex[10];
+};
+
+static const unsigned int mutex_mod[DDP_COMPONENT_ID_MAX] = {
+	[DDP_COMPONENT_AAL] = MUTEX_MOD_DISP_AAL,
+	[DDP_COMPONENT_COLOR0] = MUTEX_MOD_DISP_COLOR0,
+	[DDP_COMPONENT_COLOR1] = MUTEX_MOD_DISP_COLOR1,
+	[DDP_COMPONENT_GAMMA] = MUTEX_MOD_DISP_GAMMA,
+	[DDP_COMPONENT_OD] = MUTEX_MOD_DISP_OD,
+	[DDP_COMPONENT_OVL0] = MUTEX_MOD_DISP_OVL0,
+	[DDP_COMPONENT_OVL1] = MUTEX_MOD_DISP_OVL1,
+	[DDP_COMPONENT_PWM0] = MUTEX_MOD_DISP_PWM0,
+	[DDP_COMPONENT_PWM1] = MUTEX_MOD_DISP_PWM1,
+	[DDP_COMPONENT_RDMA0] = MUTEX_MOD_DISP_RDMA0,
+	[DDP_COMPONENT_RDMA1] = MUTEX_MOD_DISP_RDMA1,
+	[DDP_COMPONENT_RDMA2] = MUTEX_MOD_DISP_RDMA2,
+	[DDP_COMPONENT_UFOE] = MUTEX_MOD_DISP_UFOE,
+	[DDP_COMPONENT_WDMA0] = MUTEX_MOD_DISP_WDMA0,
+	[DDP_COMPONENT_WDMA1] = MUTEX_MOD_DISP_WDMA1,
+};
+
+static unsigned int mtk_ddp_mout_en(enum mtk_ddp_comp_id cur,
+				    enum mtk_ddp_comp_id next,
+				    unsigned int *addr)
+{
+	unsigned int value;
+
+	if (cur == DDP_COMPONENT_OVL0 && next == DDP_COMPONENT_COLOR0) {
+		*addr = DISP_REG_CONFIG_DISP_OVL0_MOUT_EN;
+		value = OVL0_MOUT_EN_COLOR0;
+	} else if (cur == DDP_COMPONENT_OD && next == DDP_COMPONENT_RDMA0) {
+		*addr = DISP_REG_CONFIG_DISP_OD_MOUT_EN;
+		value = OD_MOUT_EN_RDMA0;
+	} else if (cur == DDP_COMPONENT_UFOE && next == DDP_COMPONENT_DSI0) {
+		*addr = DISP_REG_CONFIG_DISP_UFOE_MOUT_EN;
+		value = UFOE_MOUT_EN_DSI0;
+	} else if (cur == DDP_COMPONENT_OVL1 && next == DDP_COMPONENT_COLOR1) {
+		*addr = DISP_REG_CONFIG_DISP_OVL1_MOUT_EN;
+		value = OVL1_MOUT_EN_COLOR1;
+	} else if (cur == DDP_COMPONENT_GAMMA && next == DDP_COMPONENT_RDMA1) {
+		*addr = DISP_REG_CONFIG_DISP_GAMMA_MOUT_EN;
+		value = GAMMA_MOUT_EN_RDMA1;
+	} else if (cur == DDP_COMPONENT_RDMA1 && next == DDP_COMPONENT_DPI0) {
+		*addr = DISP_REG_CONFIG_DISP_RDMA1_MOUT_EN;
+		value = RDMA1_MOUT_DPI0;
+	} else {
+		value = 0;
+	}
+
+	return value;
+}
+
+static unsigned int mtk_ddp_sel_in(enum mtk_ddp_comp_id cur,
+				   enum mtk_ddp_comp_id next,
+				   unsigned int *addr)
+{
+	unsigned int value;
+
+	if (cur == DDP_COMPONENT_OVL0 && next == DDP_COMPONENT_COLOR0) {
+		*addr = DISP_REG_CONFIG_DISP_COLOR0_SEL_IN;
+		value = COLOR0_SEL_IN_OVL0;
+	} else if (cur == DDP_COMPONENT_RDMA1 && next == DDP_COMPONENT_DPI0) {
+		*addr = DISP_REG_CONFIG_DPI_SEL_IN;
+		value = DPI0_SEL_IN_RDMA1;
+	} else if (cur == DDP_COMPONENT_OVL1 && next == DDP_COMPONENT_COLOR1) {
+		*addr = DISP_REG_CONFIG_DISP_COLOR1_SEL_IN;
+		value = COLOR1_SEL_IN_OVL1;
+	} else {
+		value = 0;
+	}
+
+	return value;
+}
+
+void mtk_ddp_add_comp_to_path(void __iomem *config_regs,
+			      enum mtk_ddp_comp_id cur,
+			      enum mtk_ddp_comp_id next)
+{
+	unsigned int addr, value, reg;
+
+	value = mtk_ddp_mout_en(cur, next, &addr);
+	if (value) {
+		reg = readl_relaxed(config_regs + addr) | value;
+		writel_relaxed(reg, config_regs + addr);
+	}
+
+	value = mtk_ddp_sel_in(cur, next, &addr);
+	if (value) {
+		reg = readl_relaxed(config_regs + addr) | value;
+		writel_relaxed(reg, config_regs + addr);
+	}
+}
+
+void mtk_ddp_remove_comp_from_path(void __iomem *config_regs,
+				   enum mtk_ddp_comp_id cur,
+				   enum mtk_ddp_comp_id next)
+{
+	unsigned int addr, value, reg;
+
+	value = mtk_ddp_mout_en(cur, next, &addr);
+	if (value) {
+		reg = readl_relaxed(config_regs + addr) & ~value;
+		writel_relaxed(reg, config_regs + addr);
+	}
+
+	value = mtk_ddp_sel_in(cur, next, &addr);
+	if (value) {
+		reg = readl_relaxed(config_regs + addr) & ~value;
+		writel_relaxed(reg, config_regs + addr);
+	}
+}
+
+struct mtk_disp_mutex *mtk_disp_mutex_get(struct device *dev, unsigned int id)
+{
+	struct mtk_ddp *ddp = dev_get_drvdata(dev);
+
+	if (id >= 10)
+		return ERR_PTR(-EINVAL);
+	if (ddp->mutex[id].claimed)
+		return ERR_PTR(-EBUSY);
+
+	ddp->mutex[id].claimed = true;
+
+	return &ddp->mutex[id];
+}
+
+void mtk_disp_mutex_put(struct mtk_disp_mutex *mutex)
+{
+	struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,
+					   mutex[mutex->id]);
+
+	WARN_ON(&ddp->mutex[mutex->id] != mutex);
+
+	mutex->claimed = false;
+}
+
+int mtk_disp_mutex_prepare(struct mtk_disp_mutex *mutex)
+{
+	struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,
+					   mutex[mutex->id]);
+	return clk_prepare_enable(ddp->clk);
+}
+
+void mtk_disp_mutex_unprepare(struct mtk_disp_mutex *mutex)
+{
+	struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,
+					   mutex[mutex->id]);
+	clk_disable_unprepare(ddp->clk);
+}
+
+void mtk_disp_mutex_add_comp(struct mtk_disp_mutex *mutex,
+			     enum mtk_ddp_comp_id id)
+{
+	struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,
+					   mutex[mutex->id]);
+	unsigned int reg;
+
+	WARN_ON(&ddp->mutex[mutex->id] != mutex);
+
+	switch (id) {
+	case DDP_COMPONENT_DSI0:
+		reg = MUTEX_SOF_DSI0;
+		break;
+	case DDP_COMPONENT_DSI1:
+		reg = MUTEX_SOF_DSI0;
+		break;
+	case DDP_COMPONENT_DPI0:
+		reg = MUTEX_SOF_DPI0;
+		break;
+	default:
+		reg = readl_relaxed(ddp->regs + DISP_REG_MUTEX_MOD(mutex->id));
+		reg |= mutex_mod[id];
+		writel_relaxed(reg, ddp->regs + DISP_REG_MUTEX_MOD(mutex->id));
+		return;
+	}
+
+	writel_relaxed(reg, ddp->regs + DISP_REG_MUTEX_SOF(mutex->id));
+}
+
+void mtk_disp_mutex_remove_comp(struct mtk_disp_mutex *mutex,
+				enum mtk_ddp_comp_id id)
+{
+	struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,
+					   mutex[mutex->id]);
+	unsigned int reg;
+
+	WARN_ON(&ddp->mutex[mutex->id] != mutex);
+
+	switch (id) {
+	case DDP_COMPONENT_DSI0:
+	case DDP_COMPONENT_DSI1:
+	case DDP_COMPONENT_DPI0:
+		writel_relaxed(MUTEX_SOF_SINGLE_MODE,
+			       ddp->regs + DISP_REG_MUTEX_SOF(mutex->id));
+		break;
+	default:
+		reg = readl_relaxed(ddp->regs + DISP_REG_MUTEX_MOD(mutex->id));
+		reg &= ~mutex_mod[id];
+		writel_relaxed(reg, ddp->regs + DISP_REG_MUTEX_MOD(mutex->id));
+		break;
+	}
+}
+
+void mtk_disp_mutex_enable(struct mtk_disp_mutex *mutex)
+{
+	struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,
+					   mutex[mutex->id]);
+
+	WARN_ON(&ddp->mutex[mutex->id] != mutex);
+
+	writel(1, ddp->regs + DISP_REG_MUTEX_EN(mutex->id));
+}
+
+void mtk_disp_mutex_disable(struct mtk_disp_mutex *mutex)
+{
+	struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,
+					   mutex[mutex->id]);
+
+	WARN_ON(&ddp->mutex[mutex->id] != mutex);
+
+	writel(0, ddp->regs + DISP_REG_MUTEX_EN(mutex->id));
+}
+
+static int mtk_ddp_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mtk_ddp *ddp;
+	struct resource *regs;
+	int i;
+
+	ddp = devm_kzalloc(dev, sizeof(*ddp), GFP_KERNEL);
+	if (!ddp)
+		return -ENOMEM;
+
+	for (i = 0; i < 10; i++)
+		ddp->mutex[i].id = i;
+
+	ddp->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(ddp->clk)) {
+		dev_err(dev, "Failed to get clock\n");
+		return PTR_ERR(ddp->clk);
+	}
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ddp->regs = devm_ioremap_resource(dev, regs);
+	if (IS_ERR(ddp->regs)) {
+		dev_err(dev, "Failed to map mutex registers\n");
+		return PTR_ERR(ddp->regs);
+	}
+
+	platform_set_drvdata(pdev, ddp);
+
+	return 0;
+}
+
+static int mtk_ddp_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id ddp_driver_dt_match[] = {
+	{ .compatible = "mediatek,mt8173-disp-mutex" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ddp_driver_dt_match);
+
+static struct platform_driver mtk_ddp_driver = {
+	.probe		= mtk_ddp_probe,
+	.remove		= mtk_ddp_remove,
+	.driver		= {
+		.name	= "mediatek-ddp",
+		.owner	= THIS_MODULE,
+		.of_match_table = ddp_driver_dt_match,
+	},
+};
+
+module_platform_driver(mtk_ddp_driver);
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp.h b/drivers/gpu/drm/mediatek/mtk_drm_ddp.h
new file mode 100644
index 0000000..92c1175
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp.h
@@ -0,0 +1,41 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef MTK_DRM_DDP_H
+#define MTK_DRM_DDP_H
+
+#include "mtk_drm_ddp_comp.h"
+
+struct regmap;
+struct device;
+struct mtk_disp_mutex;
+
+void mtk_ddp_add_comp_to_path(void __iomem *config_regs,
+			      enum mtk_ddp_comp_id cur,
+			      enum mtk_ddp_comp_id next);
+void mtk_ddp_remove_comp_from_path(void __iomem *config_regs,
+				   enum mtk_ddp_comp_id cur,
+				   enum mtk_ddp_comp_id next);
+
+struct mtk_disp_mutex *mtk_disp_mutex_get(struct device *dev, unsigned int id);
+int mtk_disp_mutex_prepare(struct mtk_disp_mutex *mutex);
+void mtk_disp_mutex_add_comp(struct mtk_disp_mutex *mutex,
+			     enum mtk_ddp_comp_id id);
+void mtk_disp_mutex_enable(struct mtk_disp_mutex *mutex);
+void mtk_disp_mutex_disable(struct mtk_disp_mutex *mutex);
+void mtk_disp_mutex_remove_comp(struct mtk_disp_mutex *mutex,
+				enum mtk_ddp_comp_id id);
+void mtk_disp_mutex_unprepare(struct mtk_disp_mutex *mutex);
+void mtk_disp_mutex_put(struct mtk_disp_mutex *mutex);
+
+#endif /* MTK_DRM_DDP_H */
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
new file mode 100644
index 0000000..2b96f6b
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
@@ -0,0 +1,275 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ * Authors:
+ *	YT Shen <yt.shen@mediatek.com>
+ *	CK Hu <ck.hu@mediatek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <drm/drmP.h>
+#include "mtk_drm_drv.h"
+#include "mtk_drm_plane.h"
+#include "mtk_drm_ddp_comp.h"
+
+#define DISP_REG_RDMA_INT_ENABLE		0x0000
+#define DISP_REG_RDMA_INT_STATUS		0x0004
+#define DISP_REG_RDMA_GLOBAL_CON		0x0010
+#define DISP_REG_RDMA_SIZE_CON_0		0x0014
+#define DISP_REG_RDMA_SIZE_CON_1		0x0018
+#define DISP_REG_RDMA_FIFO_CON			0x0040
+#define RDMA_FIFO_UNDERFLOW_EN				BIT(31)
+#define RDMA_FIFO_PSEUDO_SIZE(bytes)			(((bytes) / 16) << 16)
+#define RDMA_OUTPUT_VALID_FIFO_THRESHOLD(bytes)		((bytes) / 16)
+
+#define DISP_OD_EN				0x0000
+#define DISP_OD_INTEN				0x0008
+#define DISP_OD_INTSTA				0x000c
+#define DISP_OD_CFG				0x0020
+#define DISP_OD_SIZE				0x0030
+
+#define DISP_REG_UFO_START			0x0000
+
+#define DISP_COLOR_CFG_MAIN			0x0400
+#define DISP_COLOR_START			0x0c00
+#define DISP_COLOR_WIDTH			0x0c50
+#define DISP_COLOR_HEIGHT			0x0c54
+
+#define	OD_RELAY_MODE		BIT(0)
+
+#define	UFO_BYPASS		BIT(2)
+
+#define	COLOR_BYPASS_ALL	BIT(7)
+#define	COLOR_SEQ_SEL		BIT(13)
+
+static void mtk_color_config(struct mtk_ddp_comp *comp, unsigned int w,
+			     unsigned int h, unsigned int vrefresh)
+{
+	writel(w, comp->regs + DISP_COLOR_WIDTH);
+	writel(h, comp->regs + DISP_COLOR_HEIGHT);
+}
+
+static void mtk_color_start(struct mtk_ddp_comp *comp)
+{
+	writel(COLOR_BYPASS_ALL | COLOR_SEQ_SEL,
+	       comp->regs + DISP_COLOR_CFG_MAIN);
+	writel(0x1, comp->regs + DISP_COLOR_START);
+}
+
+static void mtk_od_config(struct mtk_ddp_comp *comp, unsigned int w,
+			  unsigned int h, unsigned int vrefresh)
+{
+	writel(w << 16 | h, comp->regs + DISP_OD_SIZE);
+}
+
+static void mtk_od_start(struct mtk_ddp_comp *comp)
+{
+	writel(OD_RELAY_MODE, comp->regs + DISP_OD_CFG);
+	writel(1, comp->regs + DISP_OD_EN);
+}
+
+static void mtk_rdma_start(struct mtk_ddp_comp *comp)
+{
+	unsigned int reg;
+
+	writel(0x4, comp->regs + DISP_REG_RDMA_INT_ENABLE);
+	reg = readl(comp->regs + DISP_REG_RDMA_GLOBAL_CON);
+	reg |= 1;
+	writel(reg, comp->regs + DISP_REG_RDMA_GLOBAL_CON);
+}
+
+static void mtk_rdma_config(struct mtk_ddp_comp *comp, unsigned width,
+			    unsigned height, unsigned int vrefresh)
+{
+	unsigned int threshold;
+	unsigned int reg;
+
+	reg = readl(comp->regs + DISP_REG_RDMA_SIZE_CON_0);
+	reg = (reg & ~(0xfff)) | (width & 0xfff);
+	writel(reg, comp->regs + DISP_REG_RDMA_SIZE_CON_0);
+
+	reg = readl(comp->regs + DISP_REG_RDMA_SIZE_CON_1);
+	reg = (reg & ~(0xfffff)) | (height & 0xfffff);
+	writel(reg, comp->regs + DISP_REG_RDMA_SIZE_CON_1);
+
+	/*
+	 * Enable FIFO underflow since DSI and DPI can't be blocked.
+	 * Keep the FIFO pseudo size reset default of 8 KiB. Set the
+	 * output threshold to 6 microseconds with 7/6 overhead to
+	 * account for blanking, and with a pixel depth of 4 bytes:
+	 */
+	threshold = width * height * vrefresh * 4 * 7 / 1000000;
+	reg = RDMA_FIFO_UNDERFLOW_EN |
+	      RDMA_FIFO_PSEUDO_SIZE(SZ_8K) |
+	      RDMA_OUTPUT_VALID_FIFO_THRESHOLD(threshold);
+	writel(reg, comp->regs + DISP_REG_RDMA_FIFO_CON);
+}
+
+static void mtk_ufoe_start(struct mtk_ddp_comp *comp)
+{
+	writel(UFO_BYPASS, comp->regs + DISP_REG_UFO_START);
+}
+
+static const struct mtk_ddp_comp_funcs ddp_color = {
+	.config = mtk_color_config,
+	.start = mtk_color_start,
+};
+
+static const struct mtk_ddp_comp_funcs ddp_od = {
+	.config = mtk_od_config,
+	.start = mtk_od_start,
+};
+
+static const struct mtk_ddp_comp_funcs ddp_rdma = {
+	.config = mtk_rdma_config,
+	.start = mtk_rdma_start,
+};
+
+static const struct mtk_ddp_comp_funcs ddp_ufoe = {
+	.start = mtk_ufoe_start,
+};
+
+static const char * const mtk_ddp_comp_stem[MTK_DDP_COMP_TYPE_MAX] = {
+	[MTK_DISP_OVL] = "ovl",
+	[MTK_DISP_RDMA] = "rdma",
+	[MTK_DISP_WDMA] = "wdma",
+	[MTK_DISP_COLOR] = "color",
+	[MTK_DISP_AAL] = "aal",
+	[MTK_DISP_GAMMA] = "gamma",
+	[MTK_DISP_UFOE] = "ufoe",
+	[MTK_DSI] = "dsi",
+	[MTK_DPI] = "dpi",
+	[MTK_DISP_PWM] = "pwm",
+	[MTK_DISP_MUTEX] = "mutex",
+	[MTK_DISP_OD] = "od",
+};
+
+struct mtk_ddp_comp_match {
+	enum mtk_ddp_comp_type type;
+	int alias_id;
+	const struct mtk_ddp_comp_funcs *funcs;
+};
+
+static struct mtk_ddp_comp_match mtk_ddp_matches[DDP_COMPONENT_ID_MAX] = {
+	[DDP_COMPONENT_AAL]	= { MTK_DISP_AAL,	0, NULL },
+	[DDP_COMPONENT_COLOR0]	= { MTK_DISP_COLOR,	0, &ddp_color },
+	[DDP_COMPONENT_COLOR1]	= { MTK_DISP_COLOR,	1, &ddp_color },
+	[DDP_COMPONENT_DPI0]	= { MTK_DPI,		0, NULL },
+	[DDP_COMPONENT_DSI0]	= { MTK_DSI,		0, NULL },
+	[DDP_COMPONENT_DSI1]	= { MTK_DSI,		1, NULL },
+	[DDP_COMPONENT_GAMMA]	= { MTK_DISP_GAMMA,	0, NULL },
+	[DDP_COMPONENT_OD]	= { MTK_DISP_OD,	0, &ddp_od },
+	[DDP_COMPONENT_OVL0]	= { MTK_DISP_OVL,	0, NULL },
+	[DDP_COMPONENT_OVL1]	= { MTK_DISP_OVL,	1, NULL },
+	[DDP_COMPONENT_PWM0]	= { MTK_DISP_PWM,	0, NULL },
+	[DDP_COMPONENT_RDMA0]	= { MTK_DISP_RDMA,	0, &ddp_rdma },
+	[DDP_COMPONENT_RDMA1]	= { MTK_DISP_RDMA,	1, &ddp_rdma },
+	[DDP_COMPONENT_RDMA2]	= { MTK_DISP_RDMA,	2, &ddp_rdma },
+	[DDP_COMPONENT_UFOE]	= { MTK_DISP_UFOE,	0, &ddp_ufoe },
+	[DDP_COMPONENT_WDMA0]	= { MTK_DISP_WDMA,	0, NULL },
+	[DDP_COMPONENT_WDMA1]	= { MTK_DISP_WDMA,	1, NULL },
+};
+
+int mtk_ddp_comp_get_id(struct device_node *node,
+			enum mtk_ddp_comp_type comp_type)
+{
+	int id = of_alias_get_id(node, mtk_ddp_comp_stem[comp_type]);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(mtk_ddp_matches); i++) {
+		if (comp_type == mtk_ddp_matches[i].type &&
+		    (id < 0 || id == mtk_ddp_matches[i].alias_id))
+			return i;
+	}
+
+	return -EINVAL;
+}
+
+int mtk_ddp_comp_init(struct device *dev, struct device_node *node,
+		      struct mtk_ddp_comp *comp, enum mtk_ddp_comp_id comp_id,
+		      const struct mtk_ddp_comp_funcs *funcs)
+{
+	enum mtk_ddp_comp_type type;
+	struct device_node *larb_node;
+	struct platform_device *larb_pdev;
+
+	if (comp_id < 0 || comp_id >= DDP_COMPONENT_ID_MAX)
+		return -EINVAL;
+
+	comp->id = comp_id;
+	comp->funcs = funcs ?: mtk_ddp_matches[comp_id].funcs;
+
+	if (comp_id == DDP_COMPONENT_DPI0 ||
+	    comp_id == DDP_COMPONENT_DSI0 ||
+	    comp_id == DDP_COMPONENT_PWM0) {
+		comp->regs = NULL;
+		comp->clk = NULL;
+		comp->irq = 0;
+		return 0;
+	}
+
+	comp->regs = of_iomap(node, 0);
+	comp->irq = of_irq_get(node, 0);
+	comp->clk = of_clk_get(node, 0);
+	if (IS_ERR(comp->clk))
+		comp->clk = NULL;
+
+	type = mtk_ddp_matches[comp_id].type;
+
+	/* Only DMA capable components need the LARB property */
+	comp->larb_dev = NULL;
+	if (type != MTK_DISP_OVL &&
+	    type != MTK_DISP_RDMA &&
+	    type != MTK_DISP_WDMA)
+		return 0;
+
+	larb_node = of_parse_phandle(node, "mediatek,larb", 0);
+	if (!larb_node) {
+		dev_err(dev,
+			"Missing mediadek,larb phandle in %s node\n",
+			node->full_name);
+		return -EINVAL;
+	}
+
+	larb_pdev = of_find_device_by_node(larb_node);
+	if (!larb_pdev) {
+		dev_warn(dev, "Waiting for larb device %s\n",
+			 larb_node->full_name);
+		return -EPROBE_DEFER;
+	}
+
+	comp->larb_dev = &larb_pdev->dev;
+
+	return 0;
+}
+
+int mtk_ddp_comp_register(struct drm_device *drm, struct mtk_ddp_comp *comp)
+{
+	struct mtk_drm_private *private = drm->dev_private;
+
+	if (private->ddp_comp[comp->id])
+		return -EBUSY;
+
+	private->ddp_comp[comp->id] = comp;
+	return 0;
+}
+
+void mtk_ddp_comp_unregister(struct drm_device *drm, struct mtk_ddp_comp *comp)
+{
+	struct mtk_drm_private *private = drm->dev_private;
+
+	private->ddp_comp[comp->id] = NULL;
+}
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
new file mode 100644
index 0000000..bd0c065
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
@@ -0,0 +1,148 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef MTK_DRM_DDP_COMP_H
+#define MTK_DRM_DDP_COMP_H
+
+#include <linux/io.h>
+
+struct device;
+struct device_node;
+struct drm_device;
+struct mtk_plane_state;
+
+enum mtk_ddp_comp_type {
+	MTK_DISP_OVL,
+	MTK_DISP_RDMA,
+	MTK_DISP_WDMA,
+	MTK_DISP_COLOR,
+	MTK_DISP_AAL,
+	MTK_DISP_GAMMA,
+	MTK_DISP_UFOE,
+	MTK_DSI,
+	MTK_DPI,
+	MTK_DISP_PWM,
+	MTK_DISP_MUTEX,
+	MTK_DISP_OD,
+	MTK_DDP_COMP_TYPE_MAX,
+};
+
+enum mtk_ddp_comp_id {
+	DDP_COMPONENT_AAL,
+	DDP_COMPONENT_COLOR0,
+	DDP_COMPONENT_COLOR1,
+	DDP_COMPONENT_DPI0,
+	DDP_COMPONENT_DSI0,
+	DDP_COMPONENT_DSI1,
+	DDP_COMPONENT_GAMMA,
+	DDP_COMPONENT_OD,
+	DDP_COMPONENT_OVL0,
+	DDP_COMPONENT_OVL1,
+	DDP_COMPONENT_PWM0,
+	DDP_COMPONENT_PWM1,
+	DDP_COMPONENT_RDMA0,
+	DDP_COMPONENT_RDMA1,
+	DDP_COMPONENT_RDMA2,
+	DDP_COMPONENT_UFOE,
+	DDP_COMPONENT_WDMA0,
+	DDP_COMPONENT_WDMA1,
+	DDP_COMPONENT_ID_MAX,
+};
+
+struct mtk_ddp_comp;
+
+struct mtk_ddp_comp_funcs {
+	void (*config)(struct mtk_ddp_comp *comp, unsigned int w,
+		       unsigned int h, unsigned int vrefresh);
+	void (*start)(struct mtk_ddp_comp *comp);
+	void (*stop)(struct mtk_ddp_comp *comp);
+	void (*enable_vblank)(struct mtk_ddp_comp *comp);
+	void (*disable_vblank)(struct mtk_ddp_comp *comp);
+	void (*layer_on)(struct mtk_ddp_comp *comp, unsigned int idx);
+	void (*layer_off)(struct mtk_ddp_comp *comp, unsigned int idx);
+	void (*layer_config)(struct mtk_ddp_comp *comp, unsigned int idx,
+			     struct mtk_plane_state *state);
+};
+
+struct mtk_ddp_comp {
+	struct clk *clk;
+	void __iomem *regs;
+	int irq;
+	struct device *larb_dev;
+	enum mtk_ddp_comp_id id;
+	const struct mtk_ddp_comp_funcs *funcs;
+};
+
+static inline void mtk_ddp_comp_config(struct mtk_ddp_comp *comp,
+				       unsigned int w, unsigned int h,
+				       unsigned int vrefresh)
+{
+	if (comp->funcs && comp->funcs->config)
+		comp->funcs->config(comp, w, h, vrefresh);
+}
+
+static inline void mtk_ddp_comp_start(struct mtk_ddp_comp *comp)
+{
+	if (comp->funcs && comp->funcs->start)
+		comp->funcs->start(comp);
+}
+
+static inline void mtk_ddp_comp_stop(struct mtk_ddp_comp *comp)
+{
+	if (comp->funcs && comp->funcs->stop)
+		comp->funcs->stop(comp);
+}
+
+static inline void mtk_ddp_comp_enable_vblank(struct mtk_ddp_comp *comp)
+{
+	if (comp->funcs && comp->funcs->enable_vblank)
+		comp->funcs->enable_vblank(comp);
+}
+
+static inline void mtk_ddp_comp_disable_vblank(struct mtk_ddp_comp *comp)
+{
+	if (comp->funcs && comp->funcs->disable_vblank)
+		comp->funcs->disable_vblank(comp);
+}
+
+static inline void mtk_ddp_comp_layer_on(struct mtk_ddp_comp *comp,
+					 unsigned int idx)
+{
+	if (comp->funcs && comp->funcs->layer_on)
+		comp->funcs->layer_on(comp, idx);
+}
+
+static inline void mtk_ddp_comp_layer_off(struct mtk_ddp_comp *comp,
+					  unsigned int idx)
+{
+	if (comp->funcs && comp->funcs->layer_off)
+		comp->funcs->layer_off(comp, idx);
+}
+
+static inline void mtk_ddp_comp_layer_config(struct mtk_ddp_comp *comp,
+					     unsigned int idx,
+					     struct mtk_plane_state *state)
+{
+	if (comp->funcs && comp->funcs->layer_config)
+		comp->funcs->layer_config(comp, idx, state);
+}
+
+int mtk_ddp_comp_get_id(struct device_node *node,
+			enum mtk_ddp_comp_type comp_type);
+int mtk_ddp_comp_init(struct device *dev, struct device_node *comp_node,
+		      struct mtk_ddp_comp *comp, enum mtk_ddp_comp_id comp_id,
+		      const struct mtk_ddp_comp_funcs *funcs);
+int mtk_ddp_comp_register(struct drm_device *drm, struct mtk_ddp_comp *comp);
+void mtk_ddp_comp_unregister(struct drm_device *drm, struct mtk_ddp_comp *comp);
+
+#endif /* MTK_DRM_DDP_COMP_H */
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
new file mode 100644
index 0000000..9db22b4
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -0,0 +1,577 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ * Author: YT SHEN <yt.shen@mediatek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_gem.h>
+#include <linux/component.h>
+#include <linux/iommu.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+
+#include "mtk_drm_crtc.h"
+#include "mtk_drm_ddp.h"
+#include "mtk_drm_ddp_comp.h"
+#include "mtk_drm_drv.h"
+#include "mtk_drm_fb.h"
+#include "mtk_drm_gem.h"
+
+#define DRIVER_NAME "mediatek"
+#define DRIVER_DESC "Mediatek SoC DRM"
+#define DRIVER_DATE "20150513"
+#define DRIVER_MAJOR 1
+#define DRIVER_MINOR 0
+
+static void mtk_atomic_schedule(struct mtk_drm_private *private,
+				struct drm_atomic_state *state)
+{
+	private->commit.state = state;
+	schedule_work(&private->commit.work);
+}
+
+static void mtk_atomic_wait_for_fences(struct drm_atomic_state *state)
+{
+	struct drm_plane *plane;
+	struct drm_plane_state *plane_state;
+	int i;
+
+	for_each_plane_in_state(state, plane, plane_state, i)
+		mtk_fb_wait(plane->state->fb);
+}
+
+static void mtk_atomic_complete(struct mtk_drm_private *private,
+				struct drm_atomic_state *state)
+{
+	struct drm_device *drm = private->drm;
+
+	mtk_atomic_wait_for_fences(state);
+
+	drm_atomic_helper_commit_modeset_disables(drm, state);
+	drm_atomic_helper_commit_planes(drm, state, false);
+	drm_atomic_helper_commit_modeset_enables(drm, state);
+	drm_atomic_helper_wait_for_vblanks(drm, state);
+	drm_atomic_helper_cleanup_planes(drm, state);
+	drm_atomic_state_free(state);
+}
+
+static void mtk_atomic_work(struct work_struct *work)
+{
+	struct mtk_drm_private *private = container_of(work,
+			struct mtk_drm_private, commit.work);
+
+	mtk_atomic_complete(private, private->commit.state);
+}
+
+static int mtk_atomic_commit(struct drm_device *drm,
+			     struct drm_atomic_state *state,
+			     bool async)
+{
+	struct mtk_drm_private *private = drm->dev_private;
+	int ret;
+
+	ret = drm_atomic_helper_prepare_planes(drm, state);
+	if (ret)
+		return ret;
+
+	mutex_lock(&private->commit.lock);
+	flush_work(&private->commit.work);
+
+	drm_atomic_helper_swap_state(drm, state);
+
+	if (async)
+		mtk_atomic_schedule(private, state);
+	else
+		mtk_atomic_complete(private, state);
+
+	mutex_unlock(&private->commit.lock);
+
+	return 0;
+}
+
+static const struct drm_mode_config_funcs mtk_drm_mode_config_funcs = {
+	.fb_create = mtk_drm_mode_fb_create,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = mtk_atomic_commit,
+};
+
+static const enum mtk_ddp_comp_id mtk_ddp_main[] = {
+	DDP_COMPONENT_OVL0,
+	DDP_COMPONENT_COLOR0,
+	DDP_COMPONENT_AAL,
+	DDP_COMPONENT_OD,
+	DDP_COMPONENT_RDMA0,
+	DDP_COMPONENT_UFOE,
+	DDP_COMPONENT_DSI0,
+	DDP_COMPONENT_PWM0,
+};
+
+static const enum mtk_ddp_comp_id mtk_ddp_ext[] = {
+	DDP_COMPONENT_OVL1,
+	DDP_COMPONENT_COLOR1,
+	DDP_COMPONENT_GAMMA,
+	DDP_COMPONENT_RDMA1,
+	DDP_COMPONENT_DPI0,
+};
+
+static int mtk_drm_kms_init(struct drm_device *drm)
+{
+	struct mtk_drm_private *private = drm->dev_private;
+	struct platform_device *pdev;
+	int ret;
+
+	if (!iommu_present(&platform_bus_type))
+		return -EPROBE_DEFER;
+
+	pdev = of_find_device_by_node(private->mutex_node);
+	if (!pdev) {
+		dev_err(drm->dev, "Waiting for disp-mutex device %s\n",
+			private->mutex_node->full_name);
+		of_node_put(private->mutex_node);
+		return -EPROBE_DEFER;
+	}
+	private->mutex_dev = &pdev->dev;
+
+	drm_mode_config_init(drm);
+
+	drm->mode_config.min_width = 64;
+	drm->mode_config.min_height = 64;
+
+	/*
+	 * set max width and height as default value(4096x4096).
+	 * this value would be used to check framebuffer size limitation
+	 * at drm_mode_addfb().
+	 */
+	drm->mode_config.max_width = 4096;
+	drm->mode_config.max_height = 4096;
+	drm->mode_config.funcs = &mtk_drm_mode_config_funcs;
+
+	ret = component_bind_all(drm->dev, drm);
+	if (ret)
+		goto err_config_cleanup;
+
+	/*
+	 * We currently support two fixed data streams, each statically
+	 * assigned to a crtc:
+	 * OVL0 -> COLOR0 -> AAL -> OD -> RDMA0 -> UFOE -> DSI0 ...
+	 */
+	ret = mtk_drm_crtc_create(drm, mtk_ddp_main, ARRAY_SIZE(mtk_ddp_main));
+	if (ret < 0)
+		goto err_component_unbind;
+	/* ... and OVL1 -> COLOR1 -> GAMMA -> RDMA1 -> DPI0. */
+	ret = mtk_drm_crtc_create(drm, mtk_ddp_ext, ARRAY_SIZE(mtk_ddp_ext));
+	if (ret < 0)
+		goto err_component_unbind;
+
+	/*
+	 * We don't use the drm_irq_install() helpers provided by the DRM
+	 * core, so we need to set this manually in order to allow the
+	 * DRM_IOCTL_WAIT_VBLANK to operate correctly.
+	 */
+	drm->irq_enabled = true;
+	ret = drm_vblank_init(drm, MAX_CRTC);
+	if (ret < 0)
+		goto err_component_unbind;
+
+	drm_kms_helper_poll_init(drm);
+	drm_mode_config_reset(drm);
+
+	return 0;
+
+err_component_unbind:
+	component_unbind_all(drm->dev, drm);
+err_config_cleanup:
+	drm_mode_config_cleanup(drm);
+
+	return ret;
+}
+
+static void mtk_drm_kms_deinit(struct drm_device *drm)
+{
+	drm_kms_helper_poll_fini(drm);
+
+	drm_vblank_cleanup(drm);
+	component_unbind_all(drm->dev, drm);
+	drm_mode_config_cleanup(drm);
+}
+
+static int mtk_drm_unload(struct drm_device *drm)
+{
+	mtk_drm_kms_deinit(drm);
+	drm->dev_private = NULL;
+
+	return 0;
+}
+
+static const struct vm_operations_struct mtk_drm_gem_vm_ops = {
+	.open = drm_gem_vm_open,
+	.close = drm_gem_vm_close,
+};
+
+static const struct file_operations mtk_drm_fops = {
+	.owner = THIS_MODULE,
+	.open = drm_open,
+	.release = drm_release,
+	.unlocked_ioctl = drm_ioctl,
+	.mmap = mtk_drm_gem_mmap,
+	.poll = drm_poll,
+	.read = drm_read,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = drm_compat_ioctl,
+#endif
+};
+
+static struct drm_driver mtk_drm_driver = {
+	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME |
+			   DRIVER_ATOMIC,
+	.unload = mtk_drm_unload,
+	.set_busid = drm_platform_set_busid,
+
+	.get_vblank_counter = drm_vblank_count,
+	.enable_vblank = mtk_drm_crtc_enable_vblank,
+	.disable_vblank = mtk_drm_crtc_disable_vblank,
+
+	.gem_free_object = mtk_drm_gem_free_object,
+	.gem_vm_ops = &mtk_drm_gem_vm_ops,
+	.dumb_create = mtk_drm_gem_dumb_create,
+	.dumb_map_offset = mtk_drm_gem_dumb_map_offset,
+	.dumb_destroy = drm_gem_dumb_destroy,
+
+	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
+	.gem_prime_export = drm_gem_prime_export,
+	.gem_prime_import = drm_gem_prime_import,
+	.gem_prime_get_sg_table = mtk_gem_prime_get_sg_table,
+	.gem_prime_mmap = mtk_drm_gem_mmap_buf,
+	.fops = &mtk_drm_fops,
+
+	.name = DRIVER_NAME,
+	.desc = DRIVER_DESC,
+	.date = DRIVER_DATE,
+	.major = DRIVER_MAJOR,
+	.minor = DRIVER_MINOR,
+};
+
+static int compare_of(struct device *dev, void *data)
+{
+	return dev->of_node == data;
+}
+
+static int mtk_drm_bind(struct device *dev)
+{
+	struct mtk_drm_private *private = dev_get_drvdata(dev);
+	struct drm_device *drm;
+	int ret;
+
+	drm = drm_dev_alloc(&mtk_drm_driver, dev);
+	if (!drm)
+		return -ENOMEM;
+
+	drm_dev_set_unique(drm, dev_name(dev));
+
+	ret = drm_dev_register(drm, 0);
+	if (ret < 0)
+		goto err_free;
+
+	drm->dev_private = private;
+	private->drm = drm;
+
+	ret = mtk_drm_kms_init(drm);
+	if (ret < 0)
+		goto err_unregister;
+
+	return 0;
+
+err_unregister:
+	drm_dev_unregister(drm);
+err_free:
+	drm_dev_unref(drm);
+	return ret;
+}
+
+static void mtk_drm_unbind(struct device *dev)
+{
+	struct mtk_drm_private *private = dev_get_drvdata(dev);
+
+	drm_put_dev(private->drm);
+	private->drm = NULL;
+}
+
+static const struct component_master_ops mtk_drm_ops = {
+	.bind		= mtk_drm_bind,
+	.unbind		= mtk_drm_unbind,
+};
+
+static const struct of_device_id mtk_ddp_comp_dt_ids[] = {
+	{ .compatible = "mediatek,mt8173-disp-ovl",   .data = (void *)MTK_DISP_OVL },
+	{ .compatible = "mediatek,mt8173-disp-rdma",  .data = (void *)MTK_DISP_RDMA },
+	{ .compatible = "mediatek,mt8173-disp-wdma",  .data = (void *)MTK_DISP_WDMA },
+	{ .compatible = "mediatek,mt8173-disp-color", .data = (void *)MTK_DISP_COLOR },
+	{ .compatible = "mediatek,mt8173-disp-aal",   .data = (void *)MTK_DISP_AAL},
+	{ .compatible = "mediatek,mt8173-disp-gamma", .data = (void *)MTK_DISP_GAMMA, },
+	{ .compatible = "mediatek,mt8173-disp-ufoe",  .data = (void *)MTK_DISP_UFOE },
+	{ .compatible = "mediatek,mt8173-dsi",        .data = (void *)MTK_DSI },
+	{ .compatible = "mediatek,mt8173-dpi",        .data = (void *)MTK_DPI },
+	{ .compatible = "mediatek,mt8173-disp-mutex", .data = (void *)MTK_DISP_MUTEX },
+	{ .compatible = "mediatek,mt8173-disp-pwm",   .data = (void *)MTK_DISP_PWM },
+	{ .compatible = "mediatek,mt8173-disp-od",    .data = (void *)MTK_DISP_OD },
+	{ }
+};
+
+static int mtk_drm_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mtk_drm_private *private;
+	struct resource *mem;
+	struct device_node *node;
+	struct component_match *match = NULL;
+	int ret;
+	int i;
+
+	private = devm_kzalloc(dev, sizeof(*private), GFP_KERNEL);
+	if (!private)
+		return -ENOMEM;
+
+	mutex_init(&private->commit.lock);
+	INIT_WORK(&private->commit.work, mtk_atomic_work);
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	private->config_regs = devm_ioremap_resource(dev, mem);
+	if (IS_ERR(private->config_regs)) {
+		ret = PTR_ERR(private->config_regs);
+		dev_err(dev, "Failed to ioremap mmsys-config resource: %d\n",
+			ret);
+		return ret;
+	}
+
+	/* Iterate over sibling DISP function blocks */
+	for_each_child_of_node(dev->of_node->parent, node) {
+		const struct of_device_id *of_id;
+		enum mtk_ddp_comp_type comp_type;
+		int comp_id;
+
+		of_id = of_match_node(mtk_ddp_comp_dt_ids, node);
+		if (!of_id)
+			continue;
+
+		if (!of_device_is_available(node)) {
+			dev_dbg(dev, "Skipping disabled component %s\n",
+				node->full_name);
+			continue;
+		}
+
+		comp_type = (enum mtk_ddp_comp_type)of_id->data;
+
+		if (comp_type == MTK_DISP_MUTEX) {
+			private->mutex_node = of_node_get(node);
+			continue;
+		}
+
+		comp_id = mtk_ddp_comp_get_id(node, comp_type);
+		if (comp_id < 0) {
+			dev_warn(dev, "Skipping unknown component %s\n",
+				 node->full_name);
+			continue;
+		}
+
+		private->comp_node[comp_id] = of_node_get(node);
+
+		/*
+		 * Currently only the OVL, DSI, and DPI blocks have separate
+		 * component platform drivers and initialize their own DDP
+		 * component structure. The others are initialized here.
+		 */
+		if (comp_type == MTK_DISP_OVL ||
+		    comp_type == MTK_DSI ||
+		    comp_type == MTK_DPI) {
+			dev_info(dev, "Adding component match for %s\n",
+				 node->full_name);
+			component_match_add(dev, &match, compare_of, node);
+		} else {
+			struct mtk_ddp_comp *comp;
+
+			comp = devm_kzalloc(dev, sizeof(*comp), GFP_KERNEL);
+			if (!comp) {
+				ret = -ENOMEM;
+				goto err_node;
+			}
+
+			ret = mtk_ddp_comp_init(dev, node, comp, comp_id, NULL);
+			if (ret)
+				goto err_node;
+
+			private->ddp_comp[comp_id] = comp;
+		}
+	}
+
+	if (!private->mutex_node) {
+		dev_err(dev, "Failed to find disp-mutex node\n");
+		ret = -ENODEV;
+		goto err_node;
+	}
+
+	pm_runtime_enable(dev);
+
+	platform_set_drvdata(pdev, private);
+
+	ret = component_master_add_with_match(dev, &mtk_drm_ops, match);
+	if (ret)
+		goto err_pm;
+
+	return 0;
+
+err_pm:
+	pm_runtime_disable(dev);
+err_node:
+	of_node_put(private->mutex_node);
+	for (i = 0; i < DDP_COMPONENT_ID_MAX; i++)
+		of_node_put(private->comp_node[i]);
+	return ret;
+}
+
+static int mtk_drm_remove(struct platform_device *pdev)
+{
+	struct mtk_drm_private *private = platform_get_drvdata(pdev);
+	int i;
+
+	component_master_del(&pdev->dev, &mtk_drm_ops);
+	pm_runtime_disable(&pdev->dev);
+	of_node_put(private->mutex_node);
+	for (i = 0; i < DDP_COMPONENT_ID_MAX; i++)
+		of_node_put(private->comp_node[i]);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mtk_drm_sys_suspend(struct device *dev)
+{
+	struct mtk_drm_private *private = dev_get_drvdata(dev);
+	struct drm_device *drm = private->drm;
+	struct drm_connector *conn;
+
+	drm_kms_helper_poll_disable(drm);
+
+	drm_modeset_lock_all(drm);
+	list_for_each_entry(conn, &drm->mode_config.connector_list, head) {
+		int old_dpms = conn->dpms;
+
+		if (conn->funcs->dpms)
+			conn->funcs->dpms(conn, DRM_MODE_DPMS_OFF);
+
+		/* Set the old mode back to the connector for resume */
+		conn->dpms = old_dpms;
+	}
+	drm_modeset_unlock_all(drm);
+
+	DRM_DEBUG_DRIVER("mtk_drm_sys_suspend\n");
+	return 0;
+}
+
+static int mtk_drm_sys_resume(struct device *dev)
+{
+	struct mtk_drm_private *private = dev_get_drvdata(dev);
+	struct drm_device *drm = private->drm;
+	struct drm_connector *conn;
+
+	drm_modeset_lock_all(drm);
+	list_for_each_entry(conn, &drm->mode_config.connector_list, head) {
+		int desired_mode = conn->dpms;
+
+		/*
+		 * at suspend time, we save dpms to connector->dpms,
+		 * restore the old_dpms, and at current time, the connector
+		 * dpms status must be DRM_MODE_DPMS_OFF.
+		 */
+		conn->dpms = DRM_MODE_DPMS_OFF;
+
+		/*
+		 * If the connector has been disconnected during suspend,
+		 * disconnect it from the encoder and leave it off. We'll notify
+		 * userspace at the end.
+		 */
+		if (conn->funcs->dpms)
+			conn->funcs->dpms(conn, desired_mode);
+	}
+	drm_modeset_unlock_all(drm);
+
+	drm_kms_helper_poll_enable(drm);
+
+	DRM_DEBUG_DRIVER("mtk_drm_sys_resume\n");
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(mtk_drm_pm_ops, mtk_drm_sys_suspend,
+			 mtk_drm_sys_resume);
+
+static const struct of_device_id mtk_drm_of_ids[] = {
+	{ .compatible = "mediatek,mt8173-mmsys", },
+	{ }
+};
+
+static struct platform_driver mtk_drm_platform_driver = {
+	.probe	= mtk_drm_probe,
+	.remove	= mtk_drm_remove,
+	.driver	= {
+		.name	= "mediatek-drm",
+		.of_match_table = mtk_drm_of_ids,
+		.pm     = &mtk_drm_pm_ops,
+	},
+};
+
+static struct platform_driver * const mtk_drm_drivers[] = {
+	&mtk_drm_platform_driver,
+	&mtk_disp_ovl_driver,
+};
+
+static int __init mtk_drm_init(void)
+{
+	int ret;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(mtk_drm_drivers); i++) {
+		ret = platform_driver_register(mtk_drm_drivers[i]);
+		if (ret < 0) {
+			pr_err("Failed to register %s driver: %d\n",
+			       mtk_drm_drivers[i]->driver.name, ret);
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	while (--i >= 0)
+		platform_driver_unregister(mtk_drm_drivers[i]);
+
+	return ret;
+}
+
+static void __exit mtk_drm_exit(void)
+{
+	int i;
+
+	for (i = ARRAY_SIZE(mtk_drm_drivers) - 1; i >= 0; i--)
+		platform_driver_unregister(mtk_drm_drivers[i]);
+}
+
+module_init(mtk_drm_init);
+module_exit(mtk_drm_exit);
+
+MODULE_AUTHOR("YT SHEN <yt.shen@mediatek.com>");
+MODULE_DESCRIPTION("Mediatek SoC DRM driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.h b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
new file mode 100644
index 0000000..75e1b7d
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
@@ -0,0 +1,52 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef MTK_DRM_DRV_H
+#define MTK_DRM_DRV_H
+
+#include <linux/io.h>
+#include "mtk_drm_ddp_comp.h"
+
+#define MAX_CRTC	2
+#define MAX_CONNECTOR	2
+
+struct device;
+struct device_node;
+struct drm_crtc;
+struct drm_device;
+struct drm_fb_helper;
+struct drm_property;
+struct regmap;
+
+struct mtk_drm_private {
+	struct drm_device *drm;
+
+	struct drm_crtc *crtc[MAX_CRTC];
+	unsigned int num_pipes;
+
+	struct device_node *mutex_node;
+	struct device *mutex_dev;
+	void __iomem *config_regs;
+	struct device_node *comp_node[DDP_COMPONENT_ID_MAX];
+	struct mtk_ddp_comp *ddp_comp[DDP_COMPONENT_ID_MAX];
+
+	struct {
+		struct drm_atomic_state *state;
+		struct work_struct work;
+		struct mutex lock;
+	} commit;
+};
+
+extern struct platform_driver mtk_disp_ovl_driver;
+
+#endif /* MTK_DRM_DRV_H */
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fb.c b/drivers/gpu/drm/mediatek/mtk_drm_fb.c
new file mode 100644
index 0000000..e1416cf
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_fb.c
@@ -0,0 +1,165 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_gem.h>
+#include <linux/dma-buf.h>
+#include <linux/reservation.h>
+
+#include "mtk_drm_drv.h"
+#include "mtk_drm_fb.h"
+#include "mtk_drm_gem.h"
+
+/*
+ * mtk specific framebuffer structure.
+ *
+ * @fb: drm framebuffer object.
+ * @gem_obj: array of gem objects.
+ */
+struct mtk_drm_fb {
+	struct drm_framebuffer	base;
+	/* For now we only support a single plane */
+	struct drm_gem_object	*gem_obj;
+};
+
+#define to_mtk_fb(x) container_of(x, struct mtk_drm_fb, base)
+
+struct drm_gem_object *mtk_fb_get_gem_obj(struct drm_framebuffer *fb)
+{
+	struct mtk_drm_fb *mtk_fb = to_mtk_fb(fb);
+
+	return mtk_fb->gem_obj;
+}
+
+static int mtk_drm_fb_create_handle(struct drm_framebuffer *fb,
+				    struct drm_file *file_priv,
+				    unsigned int *handle)
+{
+	struct mtk_drm_fb *mtk_fb = to_mtk_fb(fb);
+
+	return drm_gem_handle_create(file_priv, mtk_fb->gem_obj, handle);
+}
+
+static void mtk_drm_fb_destroy(struct drm_framebuffer *fb)
+{
+	struct mtk_drm_fb *mtk_fb = to_mtk_fb(fb);
+
+	drm_framebuffer_cleanup(fb);
+
+	drm_gem_object_unreference_unlocked(mtk_fb->gem_obj);
+
+	kfree(mtk_fb);
+}
+
+static const struct drm_framebuffer_funcs mtk_drm_fb_funcs = {
+	.create_handle = mtk_drm_fb_create_handle,
+	.destroy = mtk_drm_fb_destroy,
+};
+
+static struct mtk_drm_fb *mtk_drm_framebuffer_init(struct drm_device *dev,
+						   struct drm_mode_fb_cmd2 *mode,
+						   struct drm_gem_object *obj)
+{
+	struct mtk_drm_fb *mtk_fb;
+	int ret;
+
+	if (drm_format_num_planes(mode->pixel_format) != 1)
+		return ERR_PTR(-EINVAL);
+
+	mtk_fb = kzalloc(sizeof(*mtk_fb), GFP_KERNEL);
+	if (!mtk_fb)
+		return ERR_PTR(-ENOMEM);
+
+	drm_helper_mode_fill_fb_struct(&mtk_fb->base, mode);
+
+	mtk_fb->gem_obj = obj;
+
+	ret = drm_framebuffer_init(dev, &mtk_fb->base, &mtk_drm_fb_funcs);
+	if (ret) {
+		DRM_ERROR("failed to initialize framebuffer\n");
+		kfree(mtk_fb);
+		return ERR_PTR(ret);
+	}
+
+	return mtk_fb;
+}
+
+/*
+ * Wait for any exclusive fence in fb's gem object's reservation object.
+ *
+ * Returns -ERESTARTSYS if interrupted, else 0.
+ */
+int mtk_fb_wait(struct drm_framebuffer *fb)
+{
+	struct drm_gem_object *gem;
+	struct reservation_object *resv;
+	long ret;
+
+	if (!fb)
+		return 0;
+
+	gem = mtk_fb_get_gem_obj(fb);
+	if (!gem || !gem->dma_buf || !gem->dma_buf->resv)
+		return 0;
+
+	resv = gem->dma_buf->resv;
+	ret = reservation_object_wait_timeout_rcu(resv, false, true,
+						  MAX_SCHEDULE_TIMEOUT);
+	/* MAX_SCHEDULE_TIMEOUT on success, -ERESTARTSYS if interrupted */
+	if (WARN_ON(ret < 0))
+		return ret;
+
+	return 0;
+}
+
+struct drm_framebuffer *mtk_drm_mode_fb_create(struct drm_device *dev,
+					       struct drm_file *file,
+					       struct drm_mode_fb_cmd2 *cmd)
+{
+	struct mtk_drm_fb *mtk_fb;
+	struct drm_gem_object *gem;
+	unsigned int width = cmd->width;
+	unsigned int height = cmd->height;
+	unsigned int size, bpp;
+	int ret;
+
+	if (drm_format_num_planes(cmd->pixel_format) != 1)
+		return ERR_PTR(-EINVAL);
+
+	gem = drm_gem_object_lookup(dev, file, cmd->handles[0]);
+	if (!gem)
+		return ERR_PTR(-ENOENT);
+
+	bpp = drm_format_plane_cpp(cmd->pixel_format, 0);
+	size = (height - 1) * cmd->pitches[0] + width * bpp;
+	size += cmd->offsets[0];
+
+	if (gem->size < size) {
+		ret = -EINVAL;
+		goto unreference;
+	}
+
+	mtk_fb = mtk_drm_framebuffer_init(dev, cmd, gem);
+	if (IS_ERR(mtk_fb)) {
+		ret = PTR_ERR(mtk_fb);
+		goto unreference;
+	}
+
+	return &mtk_fb->base;
+
+unreference:
+	drm_gem_object_unreference_unlocked(gem);
+	return ERR_PTR(ret);
+}
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fb.h b/drivers/gpu/drm/mediatek/mtk_drm_fb.h
new file mode 100644
index 0000000..a89c7af
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_fb.h
@@ -0,0 +1,29 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef MTK_DRM_FB_H
+#define MTK_DRM_FB_H
+
+#define MAX_FB_OBJ	3
+
+struct drm_gem_object *mtk_fb_get_gem_obj(struct drm_framebuffer *fb);
+int mtk_fb_wait(struct drm_framebuffer *fb);
+struct drm_framebuffer *mtk_drm_mode_fb_create(struct drm_device *dev,
+					       struct drm_file *file,
+					       struct drm_mode_fb_cmd2 *cmd);
+
+void mtk_drm_mode_output_poll_changed(struct drm_device *dev);
+int mtk_fbdev_create(struct drm_device *dev);
+void mtk_fbdev_destroy(struct drm_device *dev);
+
+#endif /* MTK_DRM_FB_H */
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
new file mode 100644
index 0000000..96cc980
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
@@ -0,0 +1,227 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_gem.h>
+
+#include "mtk_drm_gem.h"
+
+static struct mtk_drm_gem_obj *mtk_drm_gem_init(struct drm_device *dev,
+						unsigned long size)
+{
+	struct mtk_drm_gem_obj *mtk_gem_obj;
+	int ret;
+
+	size = round_up(size, PAGE_SIZE);
+
+	mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL);
+	if (!mtk_gem_obj)
+		return ERR_PTR(-ENOMEM);
+
+	ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size);
+	if (ret < 0) {
+		DRM_ERROR("failed to initialize gem object\n");
+		kfree(mtk_gem_obj);
+		return ERR_PTR(ret);
+	}
+
+	return mtk_gem_obj;
+}
+
+struct mtk_drm_gem_obj *mtk_drm_gem_create(struct drm_device *dev,
+					   unsigned long size, bool alloc_kmap)
+{
+	struct mtk_drm_gem_obj *mtk_gem;
+	struct drm_gem_object *obj;
+	int ret;
+
+	mtk_gem = mtk_drm_gem_init(dev, size);
+	if (IS_ERR(mtk_gem))
+		return ERR_CAST(mtk_gem);
+
+	obj = &mtk_gem->base;
+
+	init_dma_attrs(&mtk_gem->dma_attrs);
+	dma_set_attr(DMA_ATTR_WRITE_COMBINE, &mtk_gem->dma_attrs);
+
+	if (!alloc_kmap)
+		dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &mtk_gem->dma_attrs);
+
+	mtk_gem->cookie = dma_alloc_attrs(dev->dev, obj->size,
+				(dma_addr_t *)&mtk_gem->dma_addr, GFP_KERNEL,
+				&mtk_gem->dma_attrs);
+	if (!mtk_gem->cookie) {
+		DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size);
+		ret = -ENOMEM;
+		goto err_gem_free;
+	}
+
+	if (alloc_kmap)
+		mtk_gem->kvaddr = mtk_gem->cookie;
+
+	DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad\n",
+			 mtk_gem->cookie, &mtk_gem->dma_addr);
+
+	return mtk_gem;
+
+err_gem_free:
+	drm_gem_object_release(obj);
+	kfree(mtk_gem);
+	return ERR_PTR(ret);
+}
+
+void mtk_drm_gem_free_object(struct drm_gem_object *obj)
+{
+	struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
+
+	dma_free_attrs(obj->dev->dev, obj->size, mtk_gem->cookie,
+		       mtk_gem->dma_addr, &mtk_gem->dma_attrs);
+
+	/* release file pointer to gem object. */
+	drm_gem_object_release(obj);
+
+	kfree(mtk_gem);
+}
+
+int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
+			    struct drm_mode_create_dumb *args)
+{
+	struct mtk_drm_gem_obj *mtk_gem;
+	int ret;
+
+	args->pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
+	args->size = args->pitch * args->height;
+
+	mtk_gem = mtk_drm_gem_create(dev, args->size, false);
+	if (IS_ERR(mtk_gem))
+		return PTR_ERR(mtk_gem);
+
+	/*
+	 * allocate a id of idr table where the obj is registered
+	 * and handle has the id what user can see.
+	 */
+	ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args->handle);
+	if (ret)
+		goto err_handle_create;
+
+	/* drop reference from allocate - handle holds it now. */
+	drm_gem_object_unreference_unlocked(&mtk_gem->base);
+
+	return 0;
+
+err_handle_create:
+	mtk_drm_gem_free_object(&mtk_gem->base);
+	return ret;
+}
+
+int mtk_drm_gem_dumb_map_offset(struct drm_file *file_priv,
+				struct drm_device *dev, uint32_t handle,
+				uint64_t *offset)
+{
+	struct drm_gem_object *obj;
+	int ret;
+
+	obj = drm_gem_object_lookup(dev, file_priv, handle);
+	if (!obj) {
+		DRM_ERROR("failed to lookup gem object.\n");
+		return -EINVAL;
+	}
+
+	ret = drm_gem_create_mmap_offset(obj);
+	if (ret)
+		goto out;
+
+	*offset = drm_vma_node_offset_addr(&obj->vma_node);
+	DRM_DEBUG_KMS("offset = 0x%llx\n", *offset);
+
+out:
+	drm_gem_object_unreference_unlocked(obj);
+	return ret;
+}
+
+static int mtk_drm_gem_object_mmap(struct drm_gem_object *obj,
+				   struct vm_area_struct *vma)
+
+{
+	int ret;
+	struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
+	struct drm_device *drm = obj->dev;
+
+	/*
+	 * dma_alloc_attrs() allocated a struct page table for mtk_gem, so clear
+	 * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap().
+	 */
+	vma->vm_flags &= ~VM_PFNMAP;
+	vma->vm_pgoff = 0;
+
+	ret = dma_mmap_attrs(drm->dev, vma, mtk_gem->cookie, mtk_gem->dma_addr,
+			     obj->size, &mtk_gem->dma_attrs);
+	if (ret)
+		drm_gem_vm_close(vma);
+
+	return ret;
+}
+
+int mtk_drm_gem_mmap_buf(struct drm_gem_object *obj, struct vm_area_struct *vma)
+{
+	int ret;
+
+	ret = drm_gem_mmap_obj(obj, obj->size, vma);
+	if (ret)
+		return ret;
+
+	return mtk_drm_gem_object_mmap(obj, vma);
+}
+
+int mtk_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	struct drm_gem_object *obj;
+	int ret;
+
+	ret = drm_gem_mmap(filp, vma);
+	if (ret)
+		return ret;
+
+	obj = vma->vm_private_data;
+
+	return mtk_drm_gem_object_mmap(obj, vma);
+}
+
+/*
+ * Allocate a sg_table for this GEM object.
+ * Note: Both the table's contents, and the sg_table itself must be freed by
+ *       the caller.
+ * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
+ */
+struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj)
+{
+	struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
+	struct drm_device *drm = obj->dev;
+	struct sg_table *sgt;
+	int ret;
+
+	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
+	if (!sgt)
+		return ERR_PTR(-ENOMEM);
+
+	ret = dma_get_sgtable_attrs(drm->dev, sgt, mtk_gem->cookie,
+				    mtk_gem->dma_addr, obj->size,
+				    &mtk_gem->dma_attrs);
+	if (ret) {
+		DRM_ERROR("failed to allocate sgt, %d\n", ret);
+		kfree(sgt);
+		return ERR_PTR(ret);
+	}
+
+	return sgt;
+}
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.h b/drivers/gpu/drm/mediatek/mtk_drm_gem.h
new file mode 100644
index 0000000..9bdeeb3
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.h
@@ -0,0 +1,55 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _MTK_DRM_GEM_H_
+#define _MTK_DRM_GEM_H_
+
+#include <drm/drm_gem.h>
+
+/*
+ * mtk drm buffer structure.
+ *
+ * @base: a gem object.
+ *	- a new handle to this gem object would be created
+ *	by drm_gem_handle_create().
+ * @cookie: the return value of dma_alloc_attrs(), keep it for dma_free_attrs()
+ * @kvaddr: kernel virtual address of gem buffer.
+ * @dma_addr: dma address of gem buffer.
+ * @dma_attrs: dma attributes of gem buffer.
+ *
+ * P.S. this object would be transferred to user as kms_bo.handle so
+ *	user can access the buffer through kms_bo.handle.
+ */
+struct mtk_drm_gem_obj {
+	struct drm_gem_object	base;
+	void			*cookie;
+	void			*kvaddr;
+	dma_addr_t		dma_addr;
+	struct dma_attrs	dma_attrs;
+};
+
+#define to_mtk_gem_obj(x)	container_of(x, struct mtk_drm_gem_obj, base)
+
+void mtk_drm_gem_free_object(struct drm_gem_object *gem);
+struct mtk_drm_gem_obj *mtk_drm_gem_create(struct drm_device *dev,
+		unsigned long size, bool alloc_kmap);
+int mtk_drm_gem_dumb_create(struct drm_file *file_priv,
+		struct drm_device *dev, struct drm_mode_create_dumb *args);
+int mtk_drm_gem_dumb_map_offset(struct drm_file *file_priv,
+		struct drm_device *dev, uint32_t handle, uint64_t *offset);
+int mtk_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
+int mtk_drm_gem_mmap_buf(struct drm_gem_object *obj,
+		struct vm_area_struct *vma);
+struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj);
+
+#endif
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
new file mode 100644
index 0000000..e9b6bf6
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
@@ -0,0 +1,242 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ * Author: CK Hu <ck.hu@mediatek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_plane_helper.h>
+
+#include "mtk_drm_crtc.h"
+#include "mtk_drm_ddp_comp.h"
+#include "mtk_drm_drv.h"
+#include "mtk_drm_fb.h"
+#include "mtk_drm_gem.h"
+#include "mtk_drm_plane.h"
+
+static const uint32_t formats[] = {
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_RGB565,
+};
+
+static void mtk_plane_enable(struct mtk_drm_plane *mtk_plane, bool enable,
+			     dma_addr_t addr, struct drm_rect *dest)
+{
+	struct drm_plane *plane = &mtk_plane->base;
+	struct mtk_plane_state *state = to_mtk_plane_state(plane->state);
+	unsigned int pitch, format;
+	int x, y;
+
+	if (WARN_ON(!plane->state || (enable && !plane->state->fb)))
+		return;
+
+	if (plane->state->fb) {
+		pitch = plane->state->fb->pitches[0];
+		format = plane->state->fb->pixel_format;
+	} else {
+		pitch = 0;
+		format = DRM_FORMAT_RGBA8888;
+	}
+
+	x = plane->state->crtc_x;
+	y = plane->state->crtc_y;
+
+	if (x < 0) {
+		addr -= x * 4;
+		x = 0;
+	}
+
+	if (y < 0) {
+		addr -= y * pitch;
+		y = 0;
+	}
+
+	state->pending.enable = enable;
+	state->pending.pitch = pitch;
+	state->pending.format = format;
+	state->pending.addr = addr;
+	state->pending.x = x;
+	state->pending.y = y;
+	state->pending.width = dest->x2 - dest->x1;
+	state->pending.height = dest->y2 - dest->y1;
+	state->pending.dirty = true;
+}
+
+static void mtk_plane_reset(struct drm_plane *plane)
+{
+	struct mtk_plane_state *state;
+
+	if (plane->state) {
+		if (plane->state->fb)
+			drm_framebuffer_unreference(plane->state->fb);
+
+		state = to_mtk_plane_state(plane->state);
+		memset(state, 0, sizeof(*state));
+	} else {
+		state = kzalloc(sizeof(*state), GFP_KERNEL);
+		if (!state)
+			return;
+		plane->state = &state->base;
+	}
+
+	state->base.plane = plane;
+	state->pending.format = DRM_FORMAT_RGB565;
+}
+
+static struct drm_plane_state *mtk_plane_duplicate_state(struct drm_plane *plane)
+{
+	struct mtk_plane_state *old_state = to_mtk_plane_state(plane->state);
+	struct mtk_plane_state *state;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return NULL;
+
+	__drm_atomic_helper_plane_duplicate_state(plane, &state->base);
+
+	WARN_ON(state->base.plane != plane);
+
+	state->pending = old_state->pending;
+
+	return &state->base;
+}
+
+static void mtk_drm_plane_destroy_state(struct drm_plane *plane,
+					struct drm_plane_state *state)
+{
+	__drm_atomic_helper_plane_destroy_state(plane, state);
+	kfree(to_mtk_plane_state(state));
+}
+
+
+static const struct drm_plane_funcs mtk_plane_funcs = {
+	.update_plane = drm_atomic_helper_update_plane,
+	.disable_plane = drm_atomic_helper_disable_plane,
+	.destroy = drm_plane_cleanup,
+	.reset = mtk_plane_reset,
+	.atomic_duplicate_state = mtk_plane_duplicate_state,
+	.atomic_destroy_state = mtk_drm_plane_destroy_state,
+};
+
+static int mtk_plane_atomic_check(struct drm_plane *plane,
+				  struct drm_plane_state *state)
+{
+	struct drm_framebuffer *fb = state->fb;
+	struct drm_crtc_state *crtc_state;
+	bool visible;
+	struct drm_rect dest = {
+		.x1 = state->crtc_x,
+		.y1 = state->crtc_y,
+		.x2 = state->crtc_x + state->crtc_w,
+		.y2 = state->crtc_y + state->crtc_h,
+	};
+	struct drm_rect src = {
+		/* 16.16 fixed point */
+		.x1 = state->src_x,
+		.y1 = state->src_y,
+		.x2 = state->src_x + state->src_w,
+		.y2 = state->src_y + state->src_h,
+	};
+	struct drm_rect clip = { 0, };
+
+	if (!fb)
+		return 0;
+
+	if (!mtk_fb_get_gem_obj(fb)) {
+		DRM_DEBUG_KMS("buffer is null\n");
+		return -EFAULT;
+	}
+
+	if (!state->crtc)
+		return 0;
+
+	crtc_state = drm_atomic_get_crtc_state(state->state, state->crtc);
+	if (IS_ERR(crtc_state))
+		return PTR_ERR(crtc_state);
+
+	clip.x2 = crtc_state->mode.hdisplay;
+	clip.y2 = crtc_state->mode.vdisplay;
+
+	return drm_plane_helper_check_update(plane, state->crtc, fb,
+					    &src, &dest, &clip,
+					    DRM_PLANE_HELPER_NO_SCALING,
+					    DRM_PLANE_HELPER_NO_SCALING,
+					    true, true, &visible);
+}
+
+static void mtk_plane_atomic_update(struct drm_plane *plane,
+				    struct drm_plane_state *old_state)
+{
+	struct mtk_plane_state *state = to_mtk_plane_state(plane->state);
+	struct drm_crtc *crtc = state->base.crtc;
+	struct drm_gem_object *gem;
+	struct mtk_drm_gem_obj *mtk_gem;
+	struct mtk_drm_plane *mtk_plane = to_mtk_plane(plane);
+	struct drm_rect dest = {
+		.x1 = state->base.crtc_x,
+		.y1 = state->base.crtc_y,
+		.x2 = state->base.crtc_x + state->base.crtc_w,
+		.y2 = state->base.crtc_y + state->base.crtc_h,
+	};
+	struct drm_rect clip = { 0, };
+
+	if (!crtc)
+		return;
+
+	clip.x2 = state->base.crtc->state->mode.hdisplay;
+	clip.y2 = state->base.crtc->state->mode.vdisplay;
+	drm_rect_intersect(&dest, &clip);
+
+	gem = mtk_fb_get_gem_obj(state->base.fb);
+	mtk_gem = to_mtk_gem_obj(gem);
+	mtk_plane_enable(mtk_plane, true, mtk_gem->dma_addr, &dest);
+
+	mtk_drm_crtc_check_flush(crtc);
+}
+
+static void mtk_plane_atomic_disable(struct drm_plane *plane,
+				     struct drm_plane_state *old_state)
+{
+	struct mtk_plane_state *state = to_mtk_plane_state(plane->state);
+
+	state->pending.enable = false;
+	wmb();
+	state->pending.dirty = true;
+}
+
+static const struct drm_plane_helper_funcs mtk_plane_helper_funcs = {
+	.atomic_check = mtk_plane_atomic_check,
+	.atomic_update = mtk_plane_atomic_update,
+	.atomic_disable = mtk_plane_atomic_disable,
+};
+
+int mtk_plane_init(struct drm_device *dev, struct mtk_drm_plane *mtk_plane,
+		   unsigned long possible_crtcs, enum drm_plane_type type,
+		   unsigned int zpos)
+{
+	int err;
+
+	err = drm_universal_plane_init(dev, &mtk_plane->base, possible_crtcs,
+			&mtk_plane_funcs, formats, ARRAY_SIZE(formats), type);
+
+	if (err) {
+		DRM_ERROR("failed to initialize plane\n");
+		return err;
+	}
+
+	drm_plane_helper_add(&mtk_plane->base, &mtk_plane_helper_funcs);
+	mtk_plane->idx = zpos;
+
+	return 0;
+}
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.h b/drivers/gpu/drm/mediatek/mtk_drm_plane.h
new file mode 100644
index 0000000..72a7b3e
--- /dev/null
+++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.h
@@ -0,0 +1,59 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ * Author: CK Hu <ck.hu@mediatek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _MTK_DRM_PLANE_H_
+#define _MTK_DRM_PLANE_H_
+
+#include <drm/drm_crtc.h>
+#include <linux/types.h>
+
+struct mtk_drm_plane {
+	struct drm_plane		base;
+	unsigned int			idx;
+};
+
+struct mtk_plane_pending_state {
+	bool				config;
+	bool				enable;
+	dma_addr_t			addr;
+	unsigned int			pitch;
+	unsigned int			format;
+	unsigned int			x;
+	unsigned int			y;
+	unsigned int			width;
+	unsigned int			height;
+	bool				dirty;
+};
+
+struct mtk_plane_state {
+	struct drm_plane_state		base;
+	struct mtk_plane_pending_state	pending;
+};
+
+static inline struct mtk_drm_plane *to_mtk_plane(struct drm_plane *plane)
+{
+	return container_of(plane, struct mtk_drm_plane, base);
+}
+
+static inline struct mtk_plane_state *
+to_mtk_plane_state(struct drm_plane_state *state)
+{
+	return container_of(state, struct mtk_plane_state, base);
+}
+
+int mtk_plane_init(struct drm_device *dev, struct mtk_drm_plane *mtk_plane,
+		   unsigned long possible_crtcs, enum drm_plane_type type,
+		   unsigned int zpos);
+
+#endif