[3/3] drm/mediatek: Use drm_gem_cma_object instead of mtk_drm_gem_obj
diff mbox series

Message ID 1540538523-1973-4-git-send-email-ck.hu@mediatek.com
State New
Headers show
Series
  • Mediatek drm driver use drm_gem_cma_object instead of mtk_drm_gem_obj
Related show

Commit Message

CK Hu Oct. 26, 2018, 7:22 a.m. UTC
After adding dma_dev in struct drm_device and
drm_gem_cma_dumb_create_no_kmap(), drm_gem_cma_object could replace
mtk_drm_gem_obj, so use drm_gem_cma_object instead of mtk_drm_gem_obj to
reduce redundant code.

Signed-off-by: CK Hu <ck.hu@mediatek.com>
---
 drivers/gpu/drm/mediatek/Makefile        |   1 -
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c  |   1 -
 drivers/gpu/drm/mediatek/mtk_drm_drv.c   |  15 +-
 drivers/gpu/drm/mediatek/mtk_drm_drv.h   |   1 -
 drivers/gpu/drm/mediatek/mtk_drm_fb.c    |   1 -
 drivers/gpu/drm/mediatek/mtk_drm_gem.c   | 243 -------------------------------
 drivers/gpu/drm/mediatek/mtk_drm_gem.h   |  56 -------
 drivers/gpu/drm/mediatek/mtk_drm_plane.c |   8 +-
 8 files changed, 11 insertions(+), 315 deletions(-)
 delete mode 100644 drivers/gpu/drm/mediatek/mtk_drm_gem.c
 delete mode 100644 drivers/gpu/drm/mediatek/mtk_drm_gem.h

Comments

Daniel Vetter Oct. 26, 2018, 10:21 a.m. UTC | #1
On Fri, Oct 26, 2018 at 03:22:03PM +0800, CK Hu wrote:
> After adding dma_dev in struct drm_device and
> drm_gem_cma_dumb_create_no_kmap(), drm_gem_cma_object could replace
> mtk_drm_gem_obj, so use drm_gem_cma_object instead of mtk_drm_gem_obj to
> reduce redundant code.
> 
> Signed-off-by: CK Hu <ck.hu@mediatek.com>

A few questions/thoughts:

- Why do you need both drm_device->dev and drm_device->dma_dev? Can't you
  just register the drm_device with the right struct device?

- You don't use drm_gem_prime_import_dev, so prime import isn't using the
  right device either.

- exynos seems to have the same or at least similar issue, stronger case
  for your patches if you can solve both.

- I'd start out with using struct drm_gem_cma_object in mtk (similar to
  what vc4 does), and then reusing as much as possible of the existing
  helpers. And then looking later on what's still left (like the support
  for leaving out the virtual mapping).

-Daniel

> ---
>  drivers/gpu/drm/mediatek/Makefile        |   1 -
>  drivers/gpu/drm/mediatek/mtk_drm_crtc.c  |   1 -
>  drivers/gpu/drm/mediatek/mtk_drm_drv.c   |  15 +-
>  drivers/gpu/drm/mediatek/mtk_drm_drv.h   |   1 -
>  drivers/gpu/drm/mediatek/mtk_drm_fb.c    |   1 -
>  drivers/gpu/drm/mediatek/mtk_drm_gem.c   | 243 -------------------------------
>  drivers/gpu/drm/mediatek/mtk_drm_gem.h   |  56 -------
>  drivers/gpu/drm/mediatek/mtk_drm_plane.c |   8 +-
>  8 files changed, 11 insertions(+), 315 deletions(-)
>  delete mode 100644 drivers/gpu/drm/mediatek/mtk_drm_gem.c
>  delete mode 100644 drivers/gpu/drm/mediatek/mtk_drm_gem.h
> 
> diff --git a/drivers/gpu/drm/mediatek/Makefile b/drivers/gpu/drm/mediatek/Makefile
> index ce83c39..c4fa126 100644
> --- a/drivers/gpu/drm/mediatek/Makefile
> +++ b/drivers/gpu/drm/mediatek/Makefile
> @@ -7,7 +7,6 @@ mediatek-drm-y := mtk_disp_color.o \
>  		  mtk_drm_ddp_comp.o \
>  		  mtk_drm_drv.o \
>  		  mtk_drm_fb.o \
> -		  mtk_drm_gem.o \
>  		  mtk_drm_plane.o \
>  		  mtk_dsi.o \
>  		  mtk_mipi_tx.o \
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index 92ecb9b..534c22a 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -24,7 +24,6 @@
>  #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"
>  
>  /**
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> index 47ec604..306ba29 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> @@ -30,7 +30,6 @@
>  #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"
> @@ -282,7 +281,7 @@ static int mtk_drm_kms_init(struct drm_device *drm)
>  		goto err_component_unbind;
>  	}
>  
> -	private->dma_dev = &pdev->dev;
> +	drm->dma_dev = &pdev->dev;
>  
>  	/*
>  	 * We don't use the drm_irq_install() helpers provided by the DRM
> @@ -320,7 +319,7 @@ static void mtk_drm_kms_deinit(struct drm_device *drm)
>  	.open = drm_open,
>  	.release = drm_release,
>  	.unlocked_ioctl = drm_ioctl,
> -	.mmap = mtk_drm_gem_mmap,
> +	.mmap = drm_gem_cma_mmap,
>  	.poll = drm_poll,
>  	.read = drm_read,
>  	.compat_ioctl = drm_compat_ioctl,
> @@ -330,17 +329,17 @@ static void mtk_drm_kms_deinit(struct drm_device *drm)
>  	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME |
>  			   DRIVER_ATOMIC,
>  
> -	.gem_free_object_unlocked = mtk_drm_gem_free_object,
> +	.gem_free_object_unlocked = drm_gem_cma_free_object,
>  	.gem_vm_ops = &drm_gem_cma_vm_ops,
> -	.dumb_create = mtk_drm_gem_dumb_create,
> +	.dumb_create = drm_gem_cma_dumb_create_no_kmap,
>  
>  	.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_import_sg_table = mtk_gem_prime_import_sg_table,
> -	.gem_prime_mmap = mtk_drm_gem_mmap_buf,
> +	.gem_prime_get_sg_table = drm_gem_cma_prime_get_sg_table,
> +	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
> +	.gem_prime_mmap = drm_gem_cma_prime_mmap,
>  	.fops = &mtk_drm_fops,
>  
>  	.name = DRIVER_NAME,
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.h b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> index ecc00ca..cbbe63b 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> @@ -41,7 +41,6 @@ struct mtk_mmsys_driver_data {
>  
>  struct mtk_drm_private {
>  	struct drm_device *drm;
> -	struct device *dma_dev;
>  
>  	unsigned int num_pipes;
>  
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fb.c b/drivers/gpu/drm/mediatek/mtk_drm_fb.c
> index be5f6f1..45c22aa 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_fb.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_fb.c
> @@ -21,7 +21,6 @@
>  
>  #include "mtk_drm_drv.h"
>  #include "mtk_drm_fb.h"
> -#include "mtk_drm_gem.h"
>  
>  static const struct drm_framebuffer_funcs mtk_drm_fb_funcs = {
>  	.create_handle = drm_gem_fb_create_handle,
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> deleted file mode 100644
> index 259b7b0..0000000
> --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> +++ /dev/null
> @@ -1,243 +0,0 @@
> -/*
> - * 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 <linux/dma-buf.h>
> -
> -#include "mtk_drm_drv.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,
> -					   size_t size, bool alloc_kmap)
> -{
> -	struct mtk_drm_private *priv = dev->dev_private;
> -	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;
> -
> -	mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE;
> -
> -	if (!alloc_kmap)
> -		mtk_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
> -
> -	mtk_gem->cookie = dma_alloc_attrs(priv->dma_dev, obj->size,
> -					  &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 size = %zu\n",
> -			 mtk_gem->cookie, &mtk_gem->dma_addr,
> -			 size);
> -
> -	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);
> -	struct mtk_drm_private *priv = obj->dev->dev_private;
> -
> -	if (mtk_gem->sg)
> -		drm_prime_gem_destroy(obj, mtk_gem->sg);
> -	else
> -		dma_free_attrs(priv->dma_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 = 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_put_unlocked(&mtk_gem->base);
> -
> -	return 0;
> -
> -err_handle_create:
> -	mtk_drm_gem_free_object(&mtk_gem->base);
> -	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 mtk_drm_private *priv = obj->dev->dev_private;
> -
> -	/*
> -	 * 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(priv->dma_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 mtk_drm_private *priv = obj->dev->dev_private;
> -	struct sg_table *sgt;
> -	int ret;
> -
> -	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
> -	if (!sgt)
> -		return ERR_PTR(-ENOMEM);
> -
> -	ret = dma_get_sgtable_attrs(priv->dma_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;
> -}
> -
> -struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
> -			struct dma_buf_attachment *attach, struct sg_table *sg)
> -{
> -	struct mtk_drm_gem_obj *mtk_gem;
> -	int ret;
> -	struct scatterlist *s;
> -	unsigned int i;
> -	dma_addr_t expected;
> -
> -	mtk_gem = mtk_drm_gem_init(dev, attach->dmabuf->size);
> -
> -	if (IS_ERR(mtk_gem))
> -		return ERR_CAST(mtk_gem);
> -
> -	expected = sg_dma_address(sg->sgl);
> -	for_each_sg(sg->sgl, s, sg->nents, i) {
> -		if (sg_dma_address(s) != expected) {
> -			DRM_ERROR("sg_table is not contiguous");
> -			ret = -EINVAL;
> -			goto err_gem_free;
> -		}
> -		expected = sg_dma_address(s) + sg_dma_len(s);
> -	}
> -
> -	mtk_gem->dma_addr = sg_dma_address(sg->sgl);
> -	mtk_gem->sg = sg;
> -
> -	return &mtk_gem->base;
> -
> -err_gem_free:
> -	kfree(mtk_gem);
> -	return ERR_PTR(ret);
> -}
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.h b/drivers/gpu/drm/mediatek/mtk_drm_gem.h
> deleted file mode 100644
> index 534639b..0000000
> --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.h
> +++ /dev/null
> @@ -1,56 +0,0 @@
> -/*
> - * 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;
> -	unsigned long		dma_attrs;
> -	struct sg_table		*sg;
> -};
> -
> -#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, size_t 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_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);
> -struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
> -			struct dma_buf_attachment *attach, struct sg_table *sg);
> -
> -#endif
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> index f7e6aa1..62de9d5 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> @@ -15,13 +15,13 @@
>  #include <drm/drmP.h>
>  #include <drm/drm_atomic.h>
>  #include <drm/drm_atomic_helper.h>
> +#include <drm/drm_gem_cma_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 u32 formats[] = {
> @@ -115,7 +115,7 @@ static void mtk_plane_atomic_update(struct drm_plane *plane,
>  	struct drm_crtc *crtc = plane->state->crtc;
>  	struct drm_framebuffer *fb = plane->state->fb;
>  	struct drm_gem_object *gem;
> -	struct mtk_drm_gem_obj *mtk_gem;
> +	struct drm_gem_cma_object *cma_obj;
>  	unsigned int pitch, format;
>  	dma_addr_t addr;
>  
> @@ -123,8 +123,8 @@ static void mtk_plane_atomic_update(struct drm_plane *plane,
>  		return;
>  
>  	gem = fb->obj[0];
> -	mtk_gem = to_mtk_gem_obj(gem);
> -	addr = mtk_gem->dma_addr;
> +	cma_obj = to_drm_gem_cma_obj(gem);
> +	addr = cma_obj->paddr;
>  	pitch = fb->pitches[0];
>  	format = fb->format->format;
>  
> -- 
> 1.9.1
>
CK Hu Oct. 29, 2018, 3:11 a.m. UTC | #2
Hi,Daniel:

On Fri, 2018-10-26 at 12:21 +0200, Daniel Vetter wrote:
> On Fri, Oct 26, 2018 at 03:22:03PM +0800, CK Hu wrote:
> > After adding dma_dev in struct drm_device and
> > drm_gem_cma_dumb_create_no_kmap(), drm_gem_cma_object could replace
> > mtk_drm_gem_obj, so use drm_gem_cma_object instead of mtk_drm_gem_obj to
> > reduce redundant code.
> > 
> > Signed-off-by: CK Hu <ck.hu@mediatek.com>
> 
> A few questions/thoughts:
> 
> - Why do you need both drm_device->dev and drm_device->dma_dev? Can't you
>   just register the drm_device with the right struct device?
> 

In [1], mmsys is the drm driver and ovl0 and ovl1 is the sub device
which has dma function.
In this drm, there are two crtc and each one is comprised of many
component.
This is an example of mt8173:

crtc0: ovl0, color0, aal, od, rdma0, ufoe, dsi0
crtc1: ovl1, color1, gamma, rdma1, dpi0

In the device node of ovl0 and ovl1, there is a 'iommus' parameter in
it, so use dma_alloc_xxx() and dma_map_xxx() with that device would get
iova rather than pa. I don't think it's a good idea to register ovl0 or
ovl1 as drm device because each one is just a component in a pipeline.
mmsys controls the clock and routing of multi-media system which include
this drm system, so it's better to register mmsys as drm device. Maybe
we could move 'iommus' parameter from ovl device to mmsys device, so the
dma device changes from ovl device to mmsys device. I'm not sure this
would be a good choice, how do you think?

[1]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/mediatek/mt8173.dtsi?h=v4.19

> - You don't use drm_gem_prime_import_dev, so prime import isn't using the
>   right device either.

Yes, you are right. I'm not familiar with whore drm core, so I start to
modify what Mediatek drm use. But this function still works for the drm
device that itself is dma device. If one day there is a drm device which
itself is not a dma device and need this function, send a patch to
modify this function and test it with that drm device. If you want me to
modify all in advance, I'm ok but need others to test it because
Mediatek drm driver does not use them.

> 
> - exynos seems to have the same or at least similar issue, stronger case
>   for your patches if you can solve both.

I'm still Mediatek's employee. If I modify other company's driver and it
is not a MUST-BE for Mediatek, Mediatek may think I give contribution to
other company. So I've better not to modify exynos driver.

> - I'd start out with using struct drm_gem_cma_object in mtk (similar to
>   what vc4 does), and then reusing as much as possible of the existing
>   helpers. And then looking later on what's still left (like the support
>   for leaving out the virtual mapping).

I'm not clear what vc4 does. It looks like that you want me to redefine
mtk_drm_gem_obj based on drm_gem_cma_object. So it would be like

struct mtk_drm_gem_obj {
	struct drm_gem_cma_object base;
	void *cookie;
	unsigned long dma_attrs;
};

I could try to modify as this and see what have left.

Regards,
CK

> 
> -Daniel
> 

[Snip...]

> > ---
> > -- 
> > 1.9.1
> > 
>
Daniel Vetter Oct. 29, 2018, 9:16 a.m. UTC | #3
On Mon, Oct 29, 2018 at 11:11:16AM +0800, CK Hu wrote:
> Hi,Daniel:
> 
> On Fri, 2018-10-26 at 12:21 +0200, Daniel Vetter wrote:
> > On Fri, Oct 26, 2018 at 03:22:03PM +0800, CK Hu wrote:
> > > After adding dma_dev in struct drm_device and
> > > drm_gem_cma_dumb_create_no_kmap(), drm_gem_cma_object could replace
> > > mtk_drm_gem_obj, so use drm_gem_cma_object instead of mtk_drm_gem_obj to
> > > reduce redundant code.
> > > 
> > > Signed-off-by: CK Hu <ck.hu@mediatek.com>
> > 
> > A few questions/thoughts:
> > 
> > - Why do you need both drm_device->dev and drm_device->dma_dev? Can't you
> >   just register the drm_device with the right struct device?
> > 
> 
> In [1], mmsys is the drm driver and ovl0 and ovl1 is the sub device
> which has dma function.
> In this drm, there are two crtc and each one is comprised of many
> component.
> This is an example of mt8173:
> 
> crtc0: ovl0, color0, aal, od, rdma0, ufoe, dsi0
> crtc1: ovl1, color1, gamma, rdma1, dpi0
> 
> In the device node of ovl0 and ovl1, there is a 'iommus' parameter in
> it, so use dma_alloc_xxx() and dma_map_xxx() with that device would get
> iova rather than pa. I don't think it's a good idea to register ovl0 or
> ovl1 as drm device because each one is just a component in a pipeline.
> mmsys controls the clock and routing of multi-media system which include
> this drm system, so it's better to register mmsys as drm device. Maybe
> we could move 'iommus' parameter from ovl device to mmsys device, so the
> dma device changes from ovl device to mmsys device. I'm not sure this
> would be a good choice, how do you think?
> 
> [1]
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/mediatek/mt8173.dtsi?h=v4.19

Ah ok. But if you have 2 blocks that make up the overall drm device, why
don't you need to switch at runtime between them? I.e. buffer allocated
for crtc0 needs to be dma-mapped to crtc0, buffer allocated to crtc1 needs
to be dma-mapped on crtc1?

And if they're both the exact same iommu, then imo it would make indeed
sense to move the iommu attribute up. Since your current code cant'
actually handle truly separate dma-mappings. And neither can your patch
series here handled separate iommu for crtc0 and crtc1.

> > - You don't use drm_gem_prime_import_dev, so prime import isn't using the
> >   right device either.
> 
> Yes, you are right. I'm not familiar with whore drm core, so I start to
> modify what Mediatek drm use. But this function still works for the drm
> device that itself is dma device. If one day there is a drm device which
> itself is not a dma device and need this function, send a patch to
> modify this function and test it with that drm device. If you want me to
> modify all in advance, I'm ok but need others to test it because
> Mediatek drm driver does not use them.

I meant to say that mediatek should use drm_gem_prime_import_dev, but
currently isn't using that. And your patch series here doesn't fix that
either. So there's more bugs left in this area.

> > - exynos seems to have the same or at least similar issue, stronger case
> >   for your patches if you can solve both.
> 
> I'm still Mediatek's employee. If I modify other company's driver and it
> is not a MUST-BE for Mediatek, Mediatek may think I give contribution to
> other company. So I've better not to modify exynos driver.

This isn't how upstream works :-)

> > - I'd start out with using struct drm_gem_cma_object in mtk (similar to
> >   what vc4 does), and then reusing as much as possible of the existing
> >   helpers. And then looking later on what's still left (like the support
> >   for leaving out the virtual mapping).
> 
> I'm not clear what vc4 does. It looks like that you want me to redefine
> mtk_drm_gem_obj based on drm_gem_cma_object. So it would be like
> 
> struct mtk_drm_gem_obj {
> 	struct drm_gem_cma_object base;
> 	void *cookie;
> 	unsigned long dma_attrs;
> };
> 
> I could try to modify as this and see what have left.

Yup, that's my suggestion. Then we can look at what mtk can use unchanged
from the core helpers. And what would need to change and so better
evaluate whether it makes sense to do that.

I still think just moving the iommu is probably best.
-Daniel
CK Hu Oct. 30, 2018, 6:54 a.m. UTC | #4
Hi, Daniel:

On Mon, 2018-10-29 at 10:16 +0100, Daniel Vetter wrote:
> On Mon, Oct 29, 2018 at 11:11:16AM +0800, CK Hu wrote:
> > Hi,Daniel:
> > 
> > On Fri, 2018-10-26 at 12:21 +0200, Daniel Vetter wrote:
> > > On Fri, Oct 26, 2018 at 03:22:03PM +0800, CK Hu wrote:
> > > > After adding dma_dev in struct drm_device and
> > > > drm_gem_cma_dumb_create_no_kmap(), drm_gem_cma_object could replace
> > > > mtk_drm_gem_obj, so use drm_gem_cma_object instead of mtk_drm_gem_obj to
> > > > reduce redundant code.
> > > > 
> > > > Signed-off-by: CK Hu <ck.hu@mediatek.com>
> > > 
> > > A few questions/thoughts:
> > > 
> > > - Why do you need both drm_device->dev and drm_device->dma_dev? Can't you
> > >   just register the drm_device with the right struct device?
> > > 
> > 
> > In [1], mmsys is the drm driver and ovl0 and ovl1 is the sub device
> > which has dma function.
> > In this drm, there are two crtc and each one is comprised of many
> > component.
> > This is an example of mt8173:
> > 
> > crtc0: ovl0, color0, aal, od, rdma0, ufoe, dsi0
> > crtc1: ovl1, color1, gamma, rdma1, dpi0
> > 
> > In the device node of ovl0 and ovl1, there is a 'iommus' parameter in
> > it, so use dma_alloc_xxx() and dma_map_xxx() with that device would get
> > iova rather than pa. I don't think it's a good idea to register ovl0 or
> > ovl1 as drm device because each one is just a component in a pipeline.
> > mmsys controls the clock and routing of multi-media system which include
> > this drm system, so it's better to register mmsys as drm device. Maybe
> > we could move 'iommus' parameter from ovl device to mmsys device, so the
> > dma device changes from ovl device to mmsys device. I'm not sure this
> > would be a good choice, how do you think?
> > 
> > [1]
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/mediatek/mt8173.dtsi?h=v4.19
> 
> Ah ok. But if you have 2 blocks that make up the overall drm device, why
> don't you need to switch at runtime between them? I.e. buffer allocated
> for crtc0 needs to be dma-mapped to crtc0, buffer allocated to crtc1 needs
> to be dma-mapped on crtc1?
> 
> And if they're both the exact same iommu, then imo it would make indeed
> sense to move the iommu attribute up. Since your current code cant'
> actually handle truly separate dma-mappings. And neither can your patch
> series here handled separate iommu for crtc0 and crtc1.

Yes, they're the exact same iommu. So I would move iommu attribute up.

> 
> > > - You don't use drm_gem_prime_import_dev, so prime import isn't using the
> > >   right device either.
> > 
> > Yes, you are right. I'm not familiar with whore drm core, so I start to
> > modify what Mediatek drm use. But this function still works for the drm
> > device that itself is dma device. If one day there is a drm device which
> > itself is not a dma device and need this function, send a patch to
> > modify this function and test it with that drm device. If you want me to
> > modify all in advance, I'm ok but need others to test it because
> > Mediatek drm driver does not use them.
> 
> I meant to say that mediatek should use drm_gem_prime_import_dev, but
> currently isn't using that. And your patch series here doesn't fix that
> either. So there's more bugs left in this area.

Great, you find a bug. My test only include export but not import. This
would take time to generate import-test environment.

> 
> > > - exynos seems to have the same or at least similar issue, stronger case
> > >   for your patches if you can solve both.
> > 
> > I'm still Mediatek's employee. If I modify other company's driver and it
> > is not a MUST-BE for Mediatek, Mediatek may think I give contribution to
> > other company. So I've better not to modify exynos driver.
> 
> This isn't how upstream works :-)

OK, because now I would not modify drm core, I would focus on Mediatek
drm driver first. If the modification of exynos driver is easy, I could
try. But if the modification of exynos is huge, I suggest that someone
who is familiar with exynos driver and have exynos platform to do it.

Regards,
CK
> 
> > > - I'd start out with using struct drm_gem_cma_object in mtk (similar to
> > >   what vc4 does), and then reusing as much as possible of the existing
> > >   helpers. And then looking later on what's still left (like the support
> > >   for leaving out the virtual mapping).
> > 
> > I'm not clear what vc4 does. It looks like that you want me to redefine
> > mtk_drm_gem_obj based on drm_gem_cma_object. So it would be like
> > 
> > struct mtk_drm_gem_obj {
> > 	struct drm_gem_cma_object base;
> > 	void *cookie;
> > 	unsigned long dma_attrs;
> > };
> > 
> > I could try to modify as this and see what have left.
> 
> Yup, that's my suggestion. Then we can look at what mtk can use unchanged
> from the core helpers. And what would need to change and so better
> evaluate whether it makes sense to do that.
> 
> I still think just moving the iommu is probably best.
> -Daniel
Daniel Vetter Oct. 30, 2018, 9:02 a.m. UTC | #5
On Tue, Oct 30, 2018 at 02:54:31PM +0800, CK Hu wrote:
> Hi, Daniel:
> 
> On Mon, 2018-10-29 at 10:16 +0100, Daniel Vetter wrote:
> > On Mon, Oct 29, 2018 at 11:11:16AM +0800, CK Hu wrote:
> > > Hi,Daniel:
> > > 
> > > On Fri, 2018-10-26 at 12:21 +0200, Daniel Vetter wrote:
> > > > On Fri, Oct 26, 2018 at 03:22:03PM +0800, CK Hu wrote:
> > > > > After adding dma_dev in struct drm_device and
> > > > > drm_gem_cma_dumb_create_no_kmap(), drm_gem_cma_object could replace
> > > > > mtk_drm_gem_obj, so use drm_gem_cma_object instead of mtk_drm_gem_obj to
> > > > > reduce redundant code.
> > > > > 
> > > > > Signed-off-by: CK Hu <ck.hu@mediatek.com>
> > > > 
> > > > A few questions/thoughts:
> > > > 
> > > > - Why do you need both drm_device->dev and drm_device->dma_dev? Can't you
> > > >   just register the drm_device with the right struct device?
> > > > 
> > > 
> > > In [1], mmsys is the drm driver and ovl0 and ovl1 is the sub device
> > > which has dma function.
> > > In this drm, there are two crtc and each one is comprised of many
> > > component.
> > > This is an example of mt8173:
> > > 
> > > crtc0: ovl0, color0, aal, od, rdma0, ufoe, dsi0
> > > crtc1: ovl1, color1, gamma, rdma1, dpi0
> > > 
> > > In the device node of ovl0 and ovl1, there is a 'iommus' parameter in
> > > it, so use dma_alloc_xxx() and dma_map_xxx() with that device would get
> > > iova rather than pa. I don't think it's a good idea to register ovl0 or
> > > ovl1 as drm device because each one is just a component in a pipeline.
> > > mmsys controls the clock and routing of multi-media system which include
> > > this drm system, so it's better to register mmsys as drm device. Maybe
> > > we could move 'iommus' parameter from ovl device to mmsys device, so the
> > > dma device changes from ovl device to mmsys device. I'm not sure this
> > > would be a good choice, how do you think?
> > > 
> > > [1]
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/mediatek/mt8173.dtsi?h=v4.19
> > 
> > Ah ok. But if you have 2 blocks that make up the overall drm device, why
> > don't you need to switch at runtime between them? I.e. buffer allocated
> > for crtc0 needs to be dma-mapped to crtc0, buffer allocated to crtc1 needs
> > to be dma-mapped on crtc1?
> > 
> > And if they're both the exact same iommu, then imo it would make indeed
> > sense to move the iommu attribute up. Since your current code cant'
> > actually handle truly separate dma-mappings. And neither can your patch
> > series here handled separate iommu for crtc0 and crtc1.
> 
> Yes, they're the exact same iommu. So I would move iommu attribute up.
> 
> > 
> > > > - You don't use drm_gem_prime_import_dev, so prime import isn't using the
> > > >   right device either.
> > > 
> > > Yes, you are right. I'm not familiar with whore drm core, so I start to
> > > modify what Mediatek drm use. But this function still works for the drm
> > > device that itself is dma device. If one day there is a drm device which
> > > itself is not a dma device and need this function, send a patch to
> > > modify this function and test it with that drm device. If you want me to
> > > modify all in advance, I'm ok but need others to test it because
> > > Mediatek drm driver does not use them.
> > 
> > I meant to say that mediatek should use drm_gem_prime_import_dev, but
> > currently isn't using that. And your patch series here doesn't fix that
> > either. So there's more bugs left in this area.
> 
> Great, you find a bug. My test only include export but not import. This
> would take time to generate import-test environment.

igt has a bunch of import tests for display iirc, using vgem.

> > > > - exynos seems to have the same or at least similar issue, stronger case
> > > >   for your patches if you can solve both.
> > > 
> > > I'm still Mediatek's employee. If I modify other company's driver and it
> > > is not a MUST-BE for Mediatek, Mediatek may think I give contribution to
> > > other company. So I've better not to modify exynos driver.
> > 
> > This isn't how upstream works :-)
> 
> OK, because now I would not modify drm core, I would focus on Mediatek
> drm driver first. If the modification of exynos driver is easy, I could
> try. But if the modification of exynos is huge, I suggest that someone
> who is familiar with exynos driver and have exynos platform to do it.

Since we now clarified that you only have 1 iommu (and that it's kinda
misplaced in the DT) I think exonys is a different case. This was more
about your original patch series, which looked like exynos could need too.
-Daniel

> 
> Regards,
> CK
> > 
> > > > - I'd start out with using struct drm_gem_cma_object in mtk (similar to
> > > >   what vc4 does), and then reusing as much as possible of the existing
> > > >   helpers. And then looking later on what's still left (like the support
> > > >   for leaving out the virtual mapping).
> > > 
> > > I'm not clear what vc4 does. It looks like that you want me to redefine
> > > mtk_drm_gem_obj based on drm_gem_cma_object. So it would be like
> > > 
> > > struct mtk_drm_gem_obj {
> > > 	struct drm_gem_cma_object base;
> > > 	void *cookie;
> > > 	unsigned long dma_attrs;
> > > };
> > > 
> > > I could try to modify as this and see what have left.
> > 
> > Yup, that's my suggestion. Then we can look at what mtk can use unchanged
> > from the core helpers. And what would need to change and so better
> > evaluate whether it makes sense to do that.
> > 
> > I still think just moving the iommu is probably best.
> > -Daniel
> 
>

Patch
diff mbox series

diff --git a/drivers/gpu/drm/mediatek/Makefile b/drivers/gpu/drm/mediatek/Makefile
index ce83c39..c4fa126 100644
--- a/drivers/gpu/drm/mediatek/Makefile
+++ b/drivers/gpu/drm/mediatek/Makefile
@@ -7,7 +7,6 @@  mediatek-drm-y := mtk_disp_color.o \
 		  mtk_drm_ddp_comp.o \
 		  mtk_drm_drv.o \
 		  mtk_drm_fb.o \
-		  mtk_drm_gem.o \
 		  mtk_drm_plane.o \
 		  mtk_dsi.o \
 		  mtk_mipi_tx.o \
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 92ecb9b..534c22a 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -24,7 +24,6 @@ 
 #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"
 
 /**
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index 47ec604..306ba29 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -30,7 +30,6 @@ 
 #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"
@@ -282,7 +281,7 @@  static int mtk_drm_kms_init(struct drm_device *drm)
 		goto err_component_unbind;
 	}
 
-	private->dma_dev = &pdev->dev;
+	drm->dma_dev = &pdev->dev;
 
 	/*
 	 * We don't use the drm_irq_install() helpers provided by the DRM
@@ -320,7 +319,7 @@  static void mtk_drm_kms_deinit(struct drm_device *drm)
 	.open = drm_open,
 	.release = drm_release,
 	.unlocked_ioctl = drm_ioctl,
-	.mmap = mtk_drm_gem_mmap,
+	.mmap = drm_gem_cma_mmap,
 	.poll = drm_poll,
 	.read = drm_read,
 	.compat_ioctl = drm_compat_ioctl,
@@ -330,17 +329,17 @@  static void mtk_drm_kms_deinit(struct drm_device *drm)
 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME |
 			   DRIVER_ATOMIC,
 
-	.gem_free_object_unlocked = mtk_drm_gem_free_object,
+	.gem_free_object_unlocked = drm_gem_cma_free_object,
 	.gem_vm_ops = &drm_gem_cma_vm_ops,
-	.dumb_create = mtk_drm_gem_dumb_create,
+	.dumb_create = drm_gem_cma_dumb_create_no_kmap,
 
 	.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_import_sg_table = mtk_gem_prime_import_sg_table,
-	.gem_prime_mmap = mtk_drm_gem_mmap_buf,
+	.gem_prime_get_sg_table = drm_gem_cma_prime_get_sg_table,
+	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+	.gem_prime_mmap = drm_gem_cma_prime_mmap,
 	.fops = &mtk_drm_fops,
 
 	.name = DRIVER_NAME,
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.h b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
index ecc00ca..cbbe63b 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
@@ -41,7 +41,6 @@  struct mtk_mmsys_driver_data {
 
 struct mtk_drm_private {
 	struct drm_device *drm;
-	struct device *dma_dev;
 
 	unsigned int num_pipes;
 
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fb.c b/drivers/gpu/drm/mediatek/mtk_drm_fb.c
index be5f6f1..45c22aa 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_fb.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_fb.c
@@ -21,7 +21,6 @@ 
 
 #include "mtk_drm_drv.h"
 #include "mtk_drm_fb.h"
-#include "mtk_drm_gem.h"
 
 static const struct drm_framebuffer_funcs mtk_drm_fb_funcs = {
 	.create_handle = drm_gem_fb_create_handle,
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
deleted file mode 100644
index 259b7b0..0000000
--- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
+++ /dev/null
@@ -1,243 +0,0 @@ 
-/*
- * 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 <linux/dma-buf.h>
-
-#include "mtk_drm_drv.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,
-					   size_t size, bool alloc_kmap)
-{
-	struct mtk_drm_private *priv = dev->dev_private;
-	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;
-
-	mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE;
-
-	if (!alloc_kmap)
-		mtk_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
-
-	mtk_gem->cookie = dma_alloc_attrs(priv->dma_dev, obj->size,
-					  &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 size = %zu\n",
-			 mtk_gem->cookie, &mtk_gem->dma_addr,
-			 size);
-
-	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);
-	struct mtk_drm_private *priv = obj->dev->dev_private;
-
-	if (mtk_gem->sg)
-		drm_prime_gem_destroy(obj, mtk_gem->sg);
-	else
-		dma_free_attrs(priv->dma_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 = 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_put_unlocked(&mtk_gem->base);
-
-	return 0;
-
-err_handle_create:
-	mtk_drm_gem_free_object(&mtk_gem->base);
-	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 mtk_drm_private *priv = obj->dev->dev_private;
-
-	/*
-	 * 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(priv->dma_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 mtk_drm_private *priv = obj->dev->dev_private;
-	struct sg_table *sgt;
-	int ret;
-
-	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
-	if (!sgt)
-		return ERR_PTR(-ENOMEM);
-
-	ret = dma_get_sgtable_attrs(priv->dma_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;
-}
-
-struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
-			struct dma_buf_attachment *attach, struct sg_table *sg)
-{
-	struct mtk_drm_gem_obj *mtk_gem;
-	int ret;
-	struct scatterlist *s;
-	unsigned int i;
-	dma_addr_t expected;
-
-	mtk_gem = mtk_drm_gem_init(dev, attach->dmabuf->size);
-
-	if (IS_ERR(mtk_gem))
-		return ERR_CAST(mtk_gem);
-
-	expected = sg_dma_address(sg->sgl);
-	for_each_sg(sg->sgl, s, sg->nents, i) {
-		if (sg_dma_address(s) != expected) {
-			DRM_ERROR("sg_table is not contiguous");
-			ret = -EINVAL;
-			goto err_gem_free;
-		}
-		expected = sg_dma_address(s) + sg_dma_len(s);
-	}
-
-	mtk_gem->dma_addr = sg_dma_address(sg->sgl);
-	mtk_gem->sg = sg;
-
-	return &mtk_gem->base;
-
-err_gem_free:
-	kfree(mtk_gem);
-	return ERR_PTR(ret);
-}
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.h b/drivers/gpu/drm/mediatek/mtk_drm_gem.h
deleted file mode 100644
index 534639b..0000000
--- a/drivers/gpu/drm/mediatek/mtk_drm_gem.h
+++ /dev/null
@@ -1,56 +0,0 @@ 
-/*
- * 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;
-	unsigned long		dma_attrs;
-	struct sg_table		*sg;
-};
-
-#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, size_t 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_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);
-struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
-			struct dma_buf_attachment *attach, struct sg_table *sg);
-
-#endif
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
index f7e6aa1..62de9d5 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
@@ -15,13 +15,13 @@ 
 #include <drm/drmP.h>
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_gem_cma_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 u32 formats[] = {
@@ -115,7 +115,7 @@  static void mtk_plane_atomic_update(struct drm_plane *plane,
 	struct drm_crtc *crtc = plane->state->crtc;
 	struct drm_framebuffer *fb = plane->state->fb;
 	struct drm_gem_object *gem;
-	struct mtk_drm_gem_obj *mtk_gem;
+	struct drm_gem_cma_object *cma_obj;
 	unsigned int pitch, format;
 	dma_addr_t addr;
 
@@ -123,8 +123,8 @@  static void mtk_plane_atomic_update(struct drm_plane *plane,
 		return;
 
 	gem = fb->obj[0];
-	mtk_gem = to_mtk_gem_obj(gem);
-	addr = mtk_gem->dma_addr;
+	cma_obj = to_drm_gem_cma_obj(gem);
+	addr = cma_obj->paddr;
 	pitch = fb->pitches[0];
 	format = fb->format->format;