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From: Neil Armstrong <narmstrong@baylibre.com>
To: dri-devel@lists.freedesktop.org
Cc: linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org,
 linux-kernel@vger.kernel.org, Neil Armstrong <narmstrong@baylibre.com>
Subject: [PATCH 6/6] drm/meson: add support for MIPI-DSI transceiver
Date: Fri,  7 Jan 2022 15:55:15 +0100
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The Amlogic G12A/G12B/SM1 SoCs embeds a Synopsys DW-MIPI-DSI transceiver (ver 1.21a),
with a custom glue managing the IP resets, clock and data input similar to the DW-HDMI
Glue on other Amlogic SoCs.

This adds support for the Glue managing the transceiver, mimicing the init flow provided
by Amlogic to setup the ENCL encoder, the glue, the transceiver, the digital D-PHY and the
Analog PHY in the proper way.

An optional "MEAS" clock can be enabled to measure the delay between each vsync feeding the
DW-MIPI-DSI transceiver.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
 drivers/gpu/drm/meson/Kconfig             |   7 +
 drivers/gpu/drm/meson/Makefile            |   1 +
 drivers/gpu/drm/meson/meson_dw_mipi_dsi.c | 383 ++++++++++++++++++++++
 drivers/gpu/drm/meson/meson_dw_mipi_dsi.h | 115 +++++++
 4 files changed, 506 insertions(+)
 create mode 100644 drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
 create mode 100644 drivers/gpu/drm/meson/meson_dw_mipi_dsi.h

diff --git a/drivers/gpu/drm/meson/Kconfig b/drivers/gpu/drm/meson/Kconfig
index 6c70fc3214af..71a1364b51e1 100644
--- a/drivers/gpu/drm/meson/Kconfig
+++ b/drivers/gpu/drm/meson/Kconfig
@@ -17,3 +17,10 @@ config DRM_MESON_DW_HDMI
 	default y if DRM_MESON
 	select DRM_DW_HDMI
 	imply DRM_DW_HDMI_I2S_AUDIO
+
+config DRM_MESON_DW_MIPI_DSI
+	tristate "MIPI DSI Synopsys Controller support for Amlogic Meson Display"
+	depends on DRM_MESON
+	default y if DRM_MESON
+	select DRM_DW_MIPI_DSI
+	select GENERIC_PHY_MIPI_DPHY
diff --git a/drivers/gpu/drm/meson/Makefile b/drivers/gpu/drm/meson/Makefile
index 833e18c20603..43071bdbd4b9 100644
--- a/drivers/gpu/drm/meson/Makefile
+++ b/drivers/gpu/drm/meson/Makefile
@@ -6,3 +6,4 @@ meson-drm-y += meson_encoder_hdmi.o meson_encoder_dsi.o
 
 obj-$(CONFIG_DRM_MESON) += meson-drm.o
 obj-$(CONFIG_DRM_MESON_DW_HDMI) += meson_dw_hdmi.o
+obj-$(CONFIG_DRM_MESON_DW_MIPI_DSI) += meson_dw_mipi_dsi.o
diff --git a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
new file mode 100644
index 000000000000..75af3eec1b74
--- /dev/null
+++ b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
@@ -0,0 +1,383 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2021 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
+ */
+
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/reset.h>
+#include <linux/phy/phy.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/bridge/dw_mipi_dsi.h>
+#include <drm/drm_mipi_dsi.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_device.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_print.h>
+
+#include "meson_drv.h"
+#include "meson_dw_mipi_dsi.h"
+#include "meson_registers.h"
+#include "meson_venc.h"
+
+#define DRIVER_NAME "meson-dw-mipi-dsi"
+#define DRIVER_DESC "Amlogic Meson MIPI-DSI DRM driver"
+
+/*  MIPI DSI/VENC Color Format Definitions */
+#define MIPI_DSI_VENC_COLOR_30B   0x0
+#define MIPI_DSI_VENC_COLOR_24B   0x1
+#define MIPI_DSI_VENC_COLOR_18B   0x2
+#define MIPI_DSI_VENC_COLOR_16B   0x3
+
+#define COLOR_16BIT_CFG_1         0x0
+#define COLOR_16BIT_CFG_2         0x1
+#define COLOR_16BIT_CFG_3         0x2
+#define COLOR_18BIT_CFG_1         0x3
+#define COLOR_18BIT_CFG_2         0x4
+#define COLOR_24BIT               0x5
+#define COLOR_20BIT_LOOSE         0x6
+#define COLOR_24_BIT_YCBCR        0x7
+#define COLOR_16BIT_YCBCR         0x8
+#define COLOR_30BIT               0x9
+#define COLOR_36BIT               0xa
+#define COLOR_12BIT               0xb
+#define COLOR_RGB_111             0xc
+#define COLOR_RGB_332             0xd
+#define COLOR_RGB_444             0xe
+
+/*  MIPI DSI Relative REGISTERs Definitions */
+/* For MIPI_DSI_TOP_CNTL */
+#define BIT_DPI_COLOR_MODE        20
+#define BIT_IN_COLOR_MODE         16
+#define BIT_CHROMA_SUBSAMPLE      14
+#define BIT_COMP2_SEL             12
+#define BIT_COMP1_SEL             10
+#define BIT_COMP0_SEL              8
+#define BIT_DE_POL                 6
+#define BIT_HSYNC_POL              5
+#define BIT_VSYNC_POL              4
+#define BIT_DPICOLORM              3
+#define BIT_DPISHUTDN              2
+#define BIT_EDPITE_INTR_PULSE      1
+#define BIT_ERR_INTR_PULSE         0
+
+struct meson_dw_mipi_dsi {
+	struct meson_drm *priv;
+	struct device *dev;
+	void __iomem *base;
+	struct phy *phy;
+	union phy_configure_opts phy_opts;
+	struct dw_mipi_dsi *dmd;
+	struct dw_mipi_dsi_plat_data pdata;
+	struct mipi_dsi_device *dsi_device;
+	const struct drm_display_mode *mode;
+	struct clk *px_clk;
+};
+
+#define encoder_to_meson_dw_mipi_dsi(x) \
+	container_of(x, struct meson_dw_mipi_dsi, encoder)
+
+static void meson_dw_mipi_dsi_hw_init(struct meson_dw_mipi_dsi *mipi_dsi)
+{
+	writel_relaxed((1 << 4) | (1 << 5) | (0 << 6),
+		       mipi_dsi->base + MIPI_DSI_TOP_CNTL);
+
+	writel_bits_relaxed(0xf, 0xf, mipi_dsi->base + MIPI_DSI_TOP_SW_RESET);
+	writel_bits_relaxed(0xf, 0, mipi_dsi->base + MIPI_DSI_TOP_SW_RESET);
+
+	writel_bits_relaxed(0x3, 0x3, mipi_dsi->base + MIPI_DSI_TOP_CLK_CNTL);
+
+	writel_relaxed(0, mipi_dsi->base + MIPI_DSI_TOP_MEM_PD);
+}
+
+static int dw_mipi_dsi_phy_init(void *priv_data)
+{
+	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
+	unsigned int dpi_data_format, venc_data_width;
+	int ret;
+
+	ret = clk_set_rate(mipi_dsi->px_clk, mipi_dsi->phy_opts.mipi_dphy.hs_clk_rate);
+	if (ret) {
+		pr_err("Failed to set DSI PLL rate %lu\n",
+		       mipi_dsi->phy_opts.mipi_dphy.hs_clk_rate);
+
+		return ret;
+	}
+
+	switch (mipi_dsi->dsi_device->format) {
+	case MIPI_DSI_FMT_RGB888:
+		dpi_data_format = COLOR_24BIT;
+		venc_data_width = MIPI_DSI_VENC_COLOR_24B;
+		break;
+	case MIPI_DSI_FMT_RGB666:
+		dpi_data_format = COLOR_18BIT_CFG_2;
+		venc_data_width = MIPI_DSI_VENC_COLOR_18B;
+		break;
+	case MIPI_DSI_FMT_RGB666_PACKED:
+	case MIPI_DSI_FMT_RGB565:
+		return -EINVAL;
+	};
+
+	/* Configure color format for DPI register */
+	writel_relaxed((dpi_data_format  << BIT_DPI_COLOR_MODE)  |
+		       (venc_data_width  << BIT_IN_COLOR_MODE) |
+			0 << BIT_COMP0_SEL |
+			1 << BIT_COMP1_SEL |
+			2 << BIT_COMP2_SEL |
+			(mipi_dsi->mode->flags & DRM_MODE_FLAG_NHSYNC ? 0 : BIT(BIT_HSYNC_POL)) |
+			(mipi_dsi->mode->flags & DRM_MODE_FLAG_NVSYNC ? 0 : BIT(BIT_VSYNC_POL)),
+			mipi_dsi->base + MIPI_DSI_TOP_CNTL);
+
+	phy_power_on(mipi_dsi->phy);
+
+	return 0;
+}
+
+static void dw_mipi_dsi_phy_power_off(void *priv_data)
+{
+	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
+
+	phy_power_off(mipi_dsi->phy);
+}
+
+static int
+dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
+			  unsigned long mode_flags, u32 lanes, u32 format,
+			  unsigned int *lane_mbps)
+{
+	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
+	int bpp;
+
+	mipi_dsi->mode = mode;
+
+	bpp = mipi_dsi_pixel_format_to_bpp(mipi_dsi->dsi_device->format);
+
+	phy_mipi_dphy_get_default_config(mode->clock * 1000,
+					 bpp, mipi_dsi->dsi_device->lanes,
+					 &mipi_dsi->phy_opts.mipi_dphy);
+
+	phy_configure(mipi_dsi->phy, &mipi_dsi->phy_opts);
+
+	*lane_mbps = mipi_dsi->phy_opts.mipi_dphy.hs_clk_rate / 1000000;
+
+	return 0;
+}
+
+static int
+dw_mipi_dsi_phy_get_timing(void *priv_data, unsigned int lane_mbps,
+			   struct dw_mipi_dsi_dphy_timing *timing)
+{
+	/* TOFIX handle other cases */
+
+	timing->clk_lp2hs = 37;
+	timing->clk_hs2lp = 135;
+	timing->data_lp2hs = 50;
+	timing->data_hs2lp = 3;
+
+	return 0;
+}
+
+static int
+dw_mipi_dsi_get_esc_clk_rate(void *priv_data, unsigned int *esc_clk_rate)
+{
+	*esc_clk_rate = 4; /* Mhz */
+
+	return 0;
+}
+
+static const struct dw_mipi_dsi_phy_ops meson_dw_mipi_dsi_phy_ops = {
+	.init = dw_mipi_dsi_phy_init,
+	.power_off = dw_mipi_dsi_phy_power_off,
+	.get_lane_mbps = dw_mipi_dsi_get_lane_mbps,
+	.get_timing = dw_mipi_dsi_phy_get_timing,
+	.get_esc_clk_rate = dw_mipi_dsi_get_esc_clk_rate,
+};
+
+static int meson_dw_mipi_dsi_bind(struct device *dev, struct device *master, void *data)
+{
+	struct meson_dw_mipi_dsi *mipi_dsi = dev_get_drvdata(dev);
+	struct drm_device *drm = data;
+	struct meson_drm *priv = drm->dev_private;
+
+	/* Check before if we are supposed to have a sub-device... */
+	if (!mipi_dsi->dsi_device) {
+		dw_mipi_dsi_remove(mipi_dsi->dmd);
+		return -EPROBE_DEFER;
+	}
+
+	mipi_dsi->priv = priv;
+
+	meson_dw_mipi_dsi_hw_init(mipi_dsi);
+
+	return 0;
+}
+
+static const struct component_ops meson_dw_mipi_dsi_ops = {
+	.bind	= meson_dw_mipi_dsi_bind,
+};
+
+static int meson_dw_mipi_dsi_host_attach(void *priv_data,
+					 struct mipi_dsi_device *device)
+{
+	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
+
+	mipi_dsi->dsi_device = device;
+
+	switch (device->format) {
+	case MIPI_DSI_FMT_RGB888:
+		break;
+	case MIPI_DSI_FMT_RGB666:
+		break;
+	case MIPI_DSI_FMT_RGB666_PACKED:
+	case MIPI_DSI_FMT_RGB565:
+		DRM_DEV_ERROR(mipi_dsi->dev, "invalid pixel format %d\n", device->format);
+		return -EINVAL;
+	};
+
+	phy_init(mipi_dsi->phy);
+
+	return 0;
+}
+
+static int meson_dw_mipi_dsi_host_detach(void *priv_data,
+					 struct mipi_dsi_device *device)
+{
+	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
+
+	if (device == mipi_dsi->dsi_device)
+		mipi_dsi->dsi_device = NULL;
+	else
+		return -EINVAL;
+
+	phy_exit(mipi_dsi->phy);
+
+	return 0;
+}
+
+static const struct dw_mipi_dsi_host_ops meson_dw_mipi_dsi_host_ops = {
+	.attach = meson_dw_mipi_dsi_host_attach,
+	.detach = meson_dw_mipi_dsi_host_detach,
+};
+
+static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
+{
+	struct meson_dw_mipi_dsi *mipi_dsi;
+	struct reset_control *top_rst;
+	struct resource *res;
+	int ret;
+
+	mipi_dsi = devm_kzalloc(&pdev->dev, sizeof(*mipi_dsi), GFP_KERNEL);
+	if (!mipi_dsi)
+		return -ENOMEM;
+
+	mipi_dsi->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mipi_dsi->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(mipi_dsi->base))
+		return PTR_ERR(mipi_dsi->base);
+
+	mipi_dsi->phy = devm_phy_get(&pdev->dev, "dphy");
+	if (IS_ERR(mipi_dsi->phy)) {
+		ret = PTR_ERR(mipi_dsi->phy);
+		dev_err(&pdev->dev, "failed to get mipi dphy: %d\n", ret);
+		return ret;
+	}
+
+	mipi_dsi->px_clk = devm_clk_get(&pdev->dev, "px_clk");
+	if (IS_ERR(mipi_dsi->px_clk)) {
+		dev_err(&pdev->dev, "Unable to get PLL clk\n");
+		return PTR_ERR(mipi_dsi->px_clk);
+	}
+
+	/*
+	 * We use a TOP reset signal because the APB reset signal
+	 * is handled by the TOP control registers.
+	 */
+	top_rst = devm_reset_control_get_exclusive(&pdev->dev, "top");
+	if (IS_ERR(top_rst)) {
+		ret = PTR_ERR(top_rst);
+
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Unable to get reset control: %d\n", ret);
+
+		return ret;
+	}
+
+	ret = clk_prepare_enable(mipi_dsi->px_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Unable to prepare/enable PX clock\n");
+		return ret;
+	}
+
+	reset_control_assert(top_rst);
+	usleep_range(10, 20);
+	reset_control_deassert(top_rst);
+
+	/* MIPI DSI Controller */
+
+	mipi_dsi->pdata.base = mipi_dsi->base;
+	mipi_dsi->pdata.max_data_lanes = 4;
+	mipi_dsi->pdata.phy_ops = &meson_dw_mipi_dsi_phy_ops;
+	mipi_dsi->pdata.host_ops = &meson_dw_mipi_dsi_host_ops;
+	mipi_dsi->pdata.priv_data = mipi_dsi;
+	platform_set_drvdata(pdev, mipi_dsi);
+
+	mipi_dsi->dmd = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata);
+	if (IS_ERR(mipi_dsi->dmd)) {
+		ret = PTR_ERR(mipi_dsi->dmd);
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev,
+				"Failed to probe dw_mipi_dsi: %d\n", ret);
+		goto err_clkdisable;
+	}
+
+	return component_add(mipi_dsi->dev, &meson_dw_mipi_dsi_ops);
+
+err_clkdisable:
+	clk_disable_unprepare(mipi_dsi->px_clk);
+
+	return ret;
+}
+
+static int meson_dw_mipi_dsi_remove(struct platform_device *pdev)
+{
+	struct meson_dw_mipi_dsi *mipi_dsi = dev_get_drvdata(&pdev->dev);
+
+	dw_mipi_dsi_remove(mipi_dsi->dmd);
+
+	component_del(mipi_dsi->dev, &meson_dw_mipi_dsi_ops);
+
+	clk_disable_unprepare(mipi_dsi->px_clk);
+
+	return 0;
+}
+
+static const struct of_device_id meson_dw_mipi_dsi_of_table[] = {
+	{ .compatible = "amlogic,meson-g12a-dw-mipi-dsi", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, meson_dw_mipi_dsi_of_table);
+
+static struct platform_driver meson_dw_mipi_dsi_platform_driver = {
+	.probe		= meson_dw_mipi_dsi_probe,
+	.remove		= meson_dw_mipi_dsi_remove,
+	.driver		= {
+		.name		= DRIVER_NAME,
+		.of_match_table	= meson_dw_mipi_dsi_of_table,
+	},
+};
+module_platform_driver(meson_dw_mipi_dsi_platform_driver);
+
+MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
diff --git a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.h b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.h
new file mode 100644
index 000000000000..4075a132e005
--- /dev/null
+++ b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.h
@@ -0,0 +1,115 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2020 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (C) 2018 Amlogic, Inc. All rights reserved.
+ */
+
+#ifndef __MESON_DW_MIPI_DSI_H
+#define __MESON_DW_MIPI_DSI_H
+
+/* Top-level registers */
+/* [31: 3]    Reserved.     Default 0.
+ *     [2] RW dpi_rst_n: Default 1.
+ *		1=Assert SW reset on mipi_dsi_host_dpi block.   0=Release reset.
+ *     [1] RW intr_rst_n: Default 1.
+ *		1=Assert SW reset on mipi_dsi_host_intr block.  0=Release reset.
+ *     [0] RW dwc_rst_n:  Default 1.
+ *		1=Assert SW reset on IP core.   0=Release reset.
+ */
+#define MIPI_DSI_TOP_SW_RESET                      0x3c0
+/* [31: 5] Reserved.   Default 0.
+ *     [4] RW manual_edpihalt: Default 0.
+ *		1=Manual suspend VencL; 0=do not suspend VencL.
+ *     [3] RW auto_edpihalt_en: Default 0.
+ *		1=Enable IP's edpihalt signal to suspend VencL;
+ *		0=IP's edpihalt signal does not affect VencL.
+ *     [2] RW clock_freerun: Apply to auto-clock gate only. Default 0.
+ *		0=Default, use auto-clock gating to save power;
+ *		1=use free-run clock, disable auto-clock gating, for debug mode.
+ *     [1] RW enable_pixclk: A manual clock gate option, due to DWC IP does not
+ *		have auto-clock gating. 1=Enable pixclk.      Default 0.
+ *     [0] RW enable_sysclk: A manual clock gate option, due to DWC IP does not
+ *		have auto-clock gating. 1=Enable sysclk.      Default 0.
+ */
+#define MIPI_DSI_TOP_CLK_CNTL                      0x3c4
+/* [31:24]    Reserved. Default 0.
+ * [23:20] RW dpi_color_mode: Define DPI pixel format. Default 0.
+ *		0=16-bit RGB565 config 1;
+ *		1=16-bit RGB565 config 2;
+ *		2=16-bit RGB565 config 3;
+ *		3=18-bit RGB666 config 1;
+ *		4=18-bit RGB666 config 2;
+ *		5=24-bit RGB888;
+ *		6=20-bit YCbCr 4:2:2;
+ *		7=24-bit YCbCr 4:2:2;
+ *		8=16-bit YCbCr 4:2:2;
+ *		9=30-bit RGB;
+ *		10=36-bit RGB;
+ *		11=12-bit YCbCr 4:2:0.
+ *    [19] Reserved. Default 0.
+ * [18:16] RW in_color_mode:  Define VENC data width. Default 0.
+ *		0=30-bit pixel;
+ *		1=24-bit pixel;
+ *		2=18-bit pixel, RGB666;
+ *		3=16-bit pixel, RGB565.
+ * [15:14] RW chroma_subsample: Define method of chroma subsampling. Default 0.
+ *		Applicable to YUV422 or YUV420 only.
+ *		0=Use even pixel's chroma;
+ *		1=Use odd pixel's chroma;
+ *		2=Use averaged value between even and odd pair.
+ * [13:12] RW comp2_sel:  Select which component to be Cr or B: Default 2.
+ *		0=comp0; 1=comp1; 2=comp2.
+ * [11:10] RW comp1_sel:  Select which component to be Cb or G: Default 1.
+ *		0=comp0; 1=comp1; 2=comp2.
+ *  [9: 8] RW comp0_sel:  Select which component to be Y  or R: Default 0.
+ *		0=comp0; 1=comp1; 2=comp2.
+ *     [7]    Reserved. Default 0.
+ *     [6] RW de_pol:  Default 0.
+ *		If DE input is active low, set to 1 to invert to active high.
+ *     [5] RW hsync_pol: Default 0.
+ *		If HS input is active low, set to 1 to invert to active high.
+ *     [4] RW vsync_pol: Default 0.
+ *		If VS input is active low, set to 1 to invert to active high.
+ *     [3] RW dpicolorm: Signal to IP.   Default 0.
+ *     [2] RW dpishutdn: Signal to IP.   Default 0.
+ *     [1]    Reserved.  Default 0.
+ *     [0]    Reserved.  Default 0.
+ */
+#define MIPI_DSI_TOP_CNTL                          0x3c8
+#define MIPI_DSI_TOP_SUSPEND_CNTL                  0x3cc
+#define MIPI_DSI_TOP_SUSPEND_LINE                  0x3d0
+#define MIPI_DSI_TOP_SUSPEND_PIX                   0x3d4
+#define MIPI_DSI_TOP_MEAS_CNTL                     0x3d8
+/* [0] R  stat_edpihalt:  edpihalt signal from IP.    Default 0. */
+#define MIPI_DSI_TOP_STAT                          0x3dc
+#define MIPI_DSI_TOP_MEAS_STAT_TE0                 0x3e0
+#define MIPI_DSI_TOP_MEAS_STAT_TE1                 0x3e4
+#define MIPI_DSI_TOP_MEAS_STAT_VS0                 0x3e8
+#define MIPI_DSI_TOP_MEAS_STAT_VS1                 0x3ec
+/* [31:16] RW intr_stat/clr. Default 0.
+ *		For each bit, read as this interrupt level status,
+ *		write 1 to clear.
+ * [31:22] Reserved
+ * [   21] stat/clr of eof interrupt
+ * [   21] vde_fall interrupt
+ * [   19] stat/clr of de_rise interrupt
+ * [   18] stat/clr of vs_fall interrupt
+ * [   17] stat/clr of vs_rise interrupt
+ * [   16] stat/clr of dwc_edpite interrupt
+ * [15: 0] RW intr_enable. Default 0.
+ *		For each bit, 1=enable this interrupt, 0=disable.
+ *	[15: 6] Reserved
+ *	[    5] eof interrupt
+ *	[    4] de_fall interrupt
+ *	[    3] de_rise interrupt
+ *	[    2] vs_fall interrupt
+ *	[    1] vs_rise interrupt
+ *	[    0] dwc_edpite interrupt
+ */
+#define MIPI_DSI_TOP_INTR_CNTL_STAT                0x3f0
+// 31: 2    Reserved.   Default 0.
+//  1: 0 RW mem_pd.     Default 3.
+#define MIPI_DSI_TOP_MEM_PD                        0x3f4
+
+#endif /* __MESON_DW_MIPI_DSI_H */