Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

6 files changed, 2217 insertions, 0 deletions

diff --git a/drivers/gpu/drm/stm/Kconfig b/drivers/gpu/drm/stm/Kconfig
new file mode 100644
index 000000000..b7d66915a
--- /dev/null
+++ b/drivers/gpu/drm/stm/Kconfig
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config DRM_STM
+	tristate "DRM Support for STMicroelectronics SoC Series"
+	depends on DRM && (ARCH_STM32 || ARCH_MULTIPLATFORM)
+	select DRM_KMS_HELPER
+	select DRM_GEM_CMA_HELPER
+	select DRM_KMS_CMA_HELPER
+	select DRM_PANEL_BRIDGE
+	select VIDEOMODE_HELPERS
+	select FB_PROVIDE_GET_FB_UNMAPPED_AREA if FB
+
+	help
+	  Enable support for the on-chip display controller on
+	  STMicroelectronics STM32 MCUs.
+	  To compile this driver as a module, choose M here: the module
+	  will be called stm-drm.
+
+config DRM_STM_DSI
+	tristate "STMicroelectronics specific extensions for Synopsys MIPI DSI"
+	depends on DRM_STM
+	select DRM_DW_MIPI_DSI
+	help
+	  Choose this option for MIPI DSI support on STMicroelectronics SoC.
diff --git a/drivers/gpu/drm/stm/Makefile b/drivers/gpu/drm/stm/Makefile
new file mode 100644
index 000000000..4df5caf01
--- /dev/null
+++ b/drivers/gpu/drm/stm/Makefile
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0-only
+stm-drm-y := \
+	drv.o \
+	ltdc.o
+
+obj-$(CONFIG_DRM_STM_DSI) += dw_mipi_dsi-stm.o
+
+obj-$(CONFIG_DRM_STM) += stm-drm.o
diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c
new file mode 100644
index 000000000..411103f01
--- /dev/null
+++ b/drivers/gpu/drm/stm/drv.c
@@ -0,0 +1,246 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          Mickael Reulier <mickael.reulier@st.com>
+ */
+
+#include <linux/component.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_vblank.h>
+
+#include "ltdc.h"
+
+#define STM_MAX_FB_WIDTH	2048
+#define STM_MAX_FB_HEIGHT	2048 /* same as width to handle orientation */
+
+static const struct drm_mode_config_funcs drv_mode_config_funcs = {
+	.fb_create = drm_gem_fb_create,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+static int stm_gem_cma_dumb_create(struct drm_file *file,
+				   struct drm_device *dev,
+				   struct drm_mode_create_dumb *args)
+{
+	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
+
+	/*
+	 * in order to optimize data transfer, pitch is aligned on
+	 * 128 bytes, height is aligned on 4 bytes
+	 */
+	args->pitch = roundup(min_pitch, 128);
+	args->height = roundup(args->height, 4);
+
+	return drm_gem_cma_dumb_create_internal(file, dev, args);
+}
+
+DEFINE_DRM_GEM_CMA_FOPS(drv_driver_fops);
+
+static struct drm_driver drv_driver = {
+	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
+	.name = "stm",
+	.desc = "STMicroelectronics SoC DRM",
+	.date = "20170330",
+	.major = 1,
+	.minor = 0,
+	.patchlevel = 0,
+	.fops = &drv_driver_fops,
+	DRM_GEM_CMA_DRIVER_OPS_WITH_DUMB_CREATE(stm_gem_cma_dumb_create),
+};
+
+static int drv_load(struct drm_device *ddev)
+{
+	struct platform_device *pdev = to_platform_device(ddev->dev);
+	struct ltdc_device *ldev;
+	int ret;
+
+	DRM_DEBUG("%s\n", __func__);
+
+	ldev = devm_kzalloc(ddev->dev, sizeof(*ldev), GFP_KERNEL);
+	if (!ldev)
+		return -ENOMEM;
+
+	ddev->dev_private = (void *)ldev;
+
+	ret = drmm_mode_config_init(ddev);
+	if (ret)
+		return ret;
+
+	/*
+	 * set max width and height as default value.
+	 * this value would be used to check framebuffer size limitation
+	 * at drm_mode_addfb().
+	 */
+	ddev->mode_config.min_width = 0;
+	ddev->mode_config.min_height = 0;
+	ddev->mode_config.max_width = STM_MAX_FB_WIDTH;
+	ddev->mode_config.max_height = STM_MAX_FB_HEIGHT;
+	ddev->mode_config.funcs = &drv_mode_config_funcs;
+
+	ret = ltdc_load(ddev);
+	if (ret)
+		return ret;
+
+	drm_mode_config_reset(ddev);
+	drm_kms_helper_poll_init(ddev);
+
+	platform_set_drvdata(pdev, ddev);
+
+	return 0;
+}
+
+static void drv_unload(struct drm_device *ddev)
+{
+	DRM_DEBUG("%s\n", __func__);
+
+	drm_kms_helper_poll_fini(ddev);
+	ltdc_unload(ddev);
+}
+
+static __maybe_unused int drv_suspend(struct device *dev)
+{
+	struct drm_device *ddev = dev_get_drvdata(dev);
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct drm_atomic_state *state;
+
+	WARN_ON(ldev->suspend_state);
+
+	state = drm_atomic_helper_suspend(ddev);
+	if (IS_ERR(state))
+		return PTR_ERR(state);
+
+	ldev->suspend_state = state;
+	pm_runtime_force_suspend(dev);
+
+	return 0;
+}
+
+static __maybe_unused int drv_resume(struct device *dev)
+{
+	struct drm_device *ddev = dev_get_drvdata(dev);
+	struct ltdc_device *ldev = ddev->dev_private;
+	int ret;
+
+	if (WARN_ON(!ldev->suspend_state))
+		return -ENOENT;
+
+	pm_runtime_force_resume(dev);
+	ret = drm_atomic_helper_resume(ddev, ldev->suspend_state);
+	if (ret)
+		pm_runtime_force_suspend(dev);
+
+	ldev->suspend_state = NULL;
+
+	return ret;
+}
+
+static __maybe_unused int drv_runtime_suspend(struct device *dev)
+{
+	struct drm_device *ddev = dev_get_drvdata(dev);
+
+	DRM_DEBUG_DRIVER("\n");
+	ltdc_suspend(ddev);
+
+	return 0;
+}
+
+static __maybe_unused int drv_runtime_resume(struct device *dev)
+{
+	struct drm_device *ddev = dev_get_drvdata(dev);
+
+	DRM_DEBUG_DRIVER("\n");
+	return ltdc_resume(ddev);
+}
+
+static const struct dev_pm_ops drv_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(drv_suspend, drv_resume)
+	SET_RUNTIME_PM_OPS(drv_runtime_suspend,
+			   drv_runtime_resume, NULL)
+};
+
+static int stm_drm_platform_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct drm_device *ddev;
+	int ret;
+
+	DRM_DEBUG("%s\n", __func__);
+
+	dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
+
+	ddev = drm_dev_alloc(&drv_driver, dev);
+	if (IS_ERR(ddev))
+		return PTR_ERR(ddev);
+
+	ret = drv_load(ddev);
+	if (ret)
+		goto err_put;
+
+	ret = drm_dev_register(ddev, 0);
+	if (ret)
+		goto err_put;
+
+	drm_fbdev_generic_setup(ddev, 16);
+
+	return 0;
+
+err_put:
+	drm_dev_put(ddev);
+
+	return ret;
+}
+
+static int stm_drm_platform_remove(struct platform_device *pdev)
+{
+	struct drm_device *ddev = platform_get_drvdata(pdev);
+
+	DRM_DEBUG("%s\n", __func__);
+
+	drm_dev_unregister(ddev);
+	drv_unload(ddev);
+	drm_dev_put(ddev);
+
+	return 0;
+}
+
+static const struct of_device_id drv_dt_ids[] = {
+	{ .compatible = "st,stm32-ltdc"},
+	{ /* end node */ },
+};
+MODULE_DEVICE_TABLE(of, drv_dt_ids);
+
+static struct platform_driver stm_drm_platform_driver = {
+	.probe = stm_drm_platform_probe,
+	.remove = stm_drm_platform_remove,
+	.driver = {
+		.name = "stm32-display",
+		.of_match_table = drv_dt_ids,
+		.pm = &drv_pm_ops,
+	},
+};
+
+module_platform_driver(stm_drm_platform_driver);
+
+MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
+MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
+MODULE_AUTHOR("Mickael Reulier <mickael.reulier@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
new file mode 100644
index 000000000..2e1f26644
--- /dev/null
+++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
@@ -0,0 +1,502 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/bridge/dw_mipi_dsi.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_print.h>
+
+#define HWVER_130			0x31333000	/* IP version 1.30 */
+#define HWVER_131			0x31333100	/* IP version 1.31 */
+
+/* DSI digital registers & bit definitions */
+#define DSI_VERSION			0x00
+#define VERSION				GENMASK(31, 8)
+
+/* DSI wrapper registers & bit definitions */
+/* Note: registers are named as in the Reference Manual */
+#define DSI_WCFGR	0x0400		/* Wrapper ConFiGuration Reg */
+#define WCFGR_DSIM	BIT(0)		/* DSI Mode */
+#define WCFGR_COLMUX	GENMASK(3, 1)	/* COLor MUltipleXing */
+
+#define DSI_WCR		0x0404		/* Wrapper Control Reg */
+#define WCR_DSIEN	BIT(3)		/* DSI ENable */
+
+#define DSI_WISR	0x040C		/* Wrapper Interrupt and Status Reg */
+#define WISR_PLLLS	BIT(8)		/* PLL Lock Status */
+#define WISR_RRS	BIT(12)		/* Regulator Ready Status */
+
+#define DSI_WPCR0	0x0418		/* Wrapper Phy Conf Reg 0 */
+#define WPCR0_UIX4	GENMASK(5, 0)	/* Unit Interval X 4 */
+#define WPCR0_TDDL	BIT(16)		/* Turn Disable Data Lanes */
+
+#define DSI_WRPCR	0x0430		/* Wrapper Regulator & Pll Ctrl Reg */
+#define WRPCR_PLLEN	BIT(0)		/* PLL ENable */
+#define WRPCR_NDIV	GENMASK(8, 2)	/* pll loop DIVision Factor */
+#define WRPCR_IDF	GENMASK(14, 11)	/* pll Input Division Factor */
+#define WRPCR_ODF	GENMASK(17, 16)	/* pll Output Division Factor */
+#define WRPCR_REGEN	BIT(24)		/* REGulator ENable */
+#define WRPCR_BGREN	BIT(28)		/* BandGap Reference ENable */
+#define IDF_MIN		1
+#define IDF_MAX		7
+#define NDIV_MIN	10
+#define NDIV_MAX	125
+#define ODF_MIN		1
+#define ODF_MAX		8
+
+/* dsi color format coding according to the datasheet */
+enum dsi_color {
+	DSI_RGB565_CONF1,
+	DSI_RGB565_CONF2,
+	DSI_RGB565_CONF3,
+	DSI_RGB666_CONF1,
+	DSI_RGB666_CONF2,
+	DSI_RGB888,
+};
+
+#define LANE_MIN_KBPS	31250
+#define LANE_MAX_KBPS	500000
+
+/* Sleep & timeout for regulator on/off, pll lock/unlock & fifo empty */
+#define SLEEP_US	1000
+#define TIMEOUT_US	200000
+
+struct dw_mipi_dsi_stm {
+	void __iomem *base;
+	struct clk *pllref_clk;
+	struct dw_mipi_dsi *dsi;
+	u32 hw_version;
+	int lane_min_kbps;
+	int lane_max_kbps;
+	struct regulator *vdd_supply;
+};
+
+static inline void dsi_write(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 val)
+{
+	writel(val, dsi->base + reg);
+}
+
+static inline u32 dsi_read(struct dw_mipi_dsi_stm *dsi, u32 reg)
+{
+	return readl(dsi->base + reg);
+}
+
+static inline void dsi_set(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 mask)
+{
+	dsi_write(dsi, reg, dsi_read(dsi, reg) | mask);
+}
+
+static inline void dsi_clear(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 mask)
+{
+	dsi_write(dsi, reg, dsi_read(dsi, reg) & ~mask);
+}
+
+static inline void dsi_update_bits(struct dw_mipi_dsi_stm *dsi, u32 reg,
+				   u32 mask, u32 val)
+{
+	dsi_write(dsi, reg, (dsi_read(dsi, reg) & ~mask) | val);
+}
+
+static enum dsi_color dsi_color_from_mipi(enum mipi_dsi_pixel_format fmt)
+{
+	switch (fmt) {
+	case MIPI_DSI_FMT_RGB888:
+		return DSI_RGB888;
+	case MIPI_DSI_FMT_RGB666:
+		return DSI_RGB666_CONF2;
+	case MIPI_DSI_FMT_RGB666_PACKED:
+		return DSI_RGB666_CONF1;
+	case MIPI_DSI_FMT_RGB565:
+		return DSI_RGB565_CONF1;
+	default:
+		DRM_DEBUG_DRIVER("MIPI color invalid, so we use rgb888\n");
+	}
+	return DSI_RGB888;
+}
+
+static int dsi_pll_get_clkout_khz(int clkin_khz, int idf, int ndiv, int odf)
+{
+	int divisor = idf * odf;
+
+	/* prevent from division by 0 */
+	if (!divisor)
+		return 0;
+
+	return DIV_ROUND_CLOSEST(clkin_khz * ndiv, divisor);
+}
+
+static int dsi_pll_get_params(struct dw_mipi_dsi_stm *dsi,
+			      int clkin_khz, int clkout_khz,
+			      int *idf, int *ndiv, int *odf)
+{
+	int i, o, n, n_min, n_max;
+	int fvco_min, fvco_max, delta, best_delta; /* all in khz */
+
+	/* Early checks preventing division by 0 & odd results */
+	if (clkin_khz <= 0 || clkout_khz <= 0)
+		return -EINVAL;
+
+	fvco_min = dsi->lane_min_kbps * 2 * ODF_MAX;
+	fvco_max = dsi->lane_max_kbps * 2 * ODF_MIN;
+
+	best_delta = 1000000; /* big started value (1000000khz) */
+
+	for (i = IDF_MIN; i <= IDF_MAX; i++) {
+		/* Compute ndiv range according to Fvco */
+		n_min = ((fvco_min * i) / (2 * clkin_khz)) + 1;
+		n_max = (fvco_max * i) / (2 * clkin_khz);
+
+		/* No need to continue idf loop if we reach ndiv max */
+		if (n_min >= NDIV_MAX)
+			break;
+
+		/* Clamp ndiv to valid values */
+		if (n_min < NDIV_MIN)
+			n_min = NDIV_MIN;
+		if (n_max > NDIV_MAX)
+			n_max = NDIV_MAX;
+
+		for (o = ODF_MIN; o <= ODF_MAX; o *= 2) {
+			n = DIV_ROUND_CLOSEST(i * o * clkout_khz, clkin_khz);
+			/* Check ndiv according to vco range */
+			if (n < n_min || n > n_max)
+				continue;
+			/* Check if new delta is better & saves parameters */
+			delta = dsi_pll_get_clkout_khz(clkin_khz, i, n, o) -
+				clkout_khz;
+			if (delta < 0)
+				delta = -delta;
+			if (delta < best_delta) {
+				*idf = i;
+				*ndiv = n;
+				*odf = o;
+				best_delta = delta;
+			}
+			/* fast return in case of "perfect result" */
+			if (!delta)
+				return 0;
+		}
+	}
+
+	return 0;
+}
+
+static int dw_mipi_dsi_phy_init(void *priv_data)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+	u32 val;
+	int ret;
+
+	/* Enable the regulator */
+	dsi_set(dsi, DSI_WRPCR, WRPCR_REGEN | WRPCR_BGREN);
+	ret = readl_poll_timeout(dsi->base + DSI_WISR, val, val & WISR_RRS,
+				 SLEEP_US, TIMEOUT_US);
+	if (ret)
+		DRM_DEBUG_DRIVER("!TIMEOUT! waiting REGU, let's continue\n");
+
+	/* Enable the DSI PLL & wait for its lock */
+	dsi_set(dsi, DSI_WRPCR, WRPCR_PLLEN);
+	ret = readl_poll_timeout(dsi->base + DSI_WISR, val, val & WISR_PLLLS,
+				 SLEEP_US, TIMEOUT_US);
+	if (ret)
+		DRM_DEBUG_DRIVER("!TIMEOUT! waiting PLL, let's continue\n");
+
+	return 0;
+}
+
+static void dw_mipi_dsi_phy_power_on(void *priv_data)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Enable the DSI wrapper */
+	dsi_set(dsi, DSI_WCR, WCR_DSIEN);
+}
+
+static void dw_mipi_dsi_phy_power_off(void *priv_data)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Disable the DSI wrapper */
+	dsi_clear(dsi, DSI_WCR, WCR_DSIEN);
+}
+
+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 dw_mipi_dsi_stm *dsi = priv_data;
+	unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+	int ret, bpp;
+	u32 val;
+
+	/* Update lane capabilities according to hw version */
+	dsi->lane_min_kbps = LANE_MIN_KBPS;
+	dsi->lane_max_kbps = LANE_MAX_KBPS;
+	if (dsi->hw_version == HWVER_131) {
+		dsi->lane_min_kbps *= 2;
+		dsi->lane_max_kbps *= 2;
+	}
+
+	pll_in_khz = (unsigned int)(clk_get_rate(dsi->pllref_clk) / 1000);
+
+	/* Compute requested pll out */
+	bpp = mipi_dsi_pixel_format_to_bpp(format);
+	pll_out_khz = mode->clock * bpp / lanes;
+
+	/* Add 20% to pll out to be higher than pixel bw (burst mode only) */
+	if (mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
+		pll_out_khz = (pll_out_khz * 12) / 10;
+
+	if (pll_out_khz > dsi->lane_max_kbps) {
+		pll_out_khz = dsi->lane_max_kbps;
+		DRM_WARN("Warning max phy mbps is used\n");
+	}
+	if (pll_out_khz < dsi->lane_min_kbps) {
+		pll_out_khz = dsi->lane_min_kbps;
+		DRM_WARN("Warning min phy mbps is used\n");
+	}
+
+	/* Compute best pll parameters */
+	idf = 0;
+	ndiv = 0;
+	odf = 0;
+	ret = dsi_pll_get_params(dsi, pll_in_khz, pll_out_khz,
+				 &idf, &ndiv, &odf);
+	if (ret)
+		DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
+
+	/* Get the adjusted pll out value */
+	pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+	/* Set the PLL division factors */
+	dsi_update_bits(dsi, DSI_WRPCR,	WRPCR_NDIV | WRPCR_IDF | WRPCR_ODF,
+			(ndiv << 2) | (idf << 11) | ((ffs(odf) - 1) << 16));
+
+	/* Compute uix4 & set the bit period in high-speed mode */
+	val = 4000000 / pll_out_khz;
+	dsi_update_bits(dsi, DSI_WPCR0, WPCR0_UIX4, val);
+
+	/* Select video mode by resetting DSIM bit */
+	dsi_clear(dsi, DSI_WCFGR, WCFGR_DSIM);
+
+	/* Select the color coding */
+	dsi_update_bits(dsi, DSI_WCFGR, WCFGR_COLMUX,
+			dsi_color_from_mipi(format) << 1);
+
+	*lane_mbps = pll_out_khz / 1000;
+
+	DRM_DEBUG_DRIVER("pll_in %ukHz pll_out %ukHz lane_mbps %uMHz\n",
+			 pll_in_khz, pll_out_khz, *lane_mbps);
+
+	return 0;
+}
+
+static int
+dw_mipi_dsi_phy_get_timing(void *priv_data, unsigned int lane_mbps,
+			   struct dw_mipi_dsi_dphy_timing *timing)
+{
+	timing->clk_hs2lp = 0x40;
+	timing->clk_lp2hs = 0x40;
+	timing->data_hs2lp = 0x40;
+	timing->data_lp2hs = 0x40;
+
+	return 0;
+}
+
+static const struct dw_mipi_dsi_phy_ops dw_mipi_dsi_stm_phy_ops = {
+	.init = dw_mipi_dsi_phy_init,
+	.power_on = dw_mipi_dsi_phy_power_on,
+	.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,
+};
+
+static struct dw_mipi_dsi_plat_data dw_mipi_dsi_stm_plat_data = {
+	.max_data_lanes = 2,
+	.phy_ops = &dw_mipi_dsi_stm_phy_ops,
+};
+
+static const struct of_device_id dw_mipi_dsi_stm_dt_ids[] = {
+	{ .compatible = "st,stm32-dsi", .data = &dw_mipi_dsi_stm_plat_data, },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, dw_mipi_dsi_stm_dt_ids);
+
+static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct dw_mipi_dsi_stm *dsi;
+	struct clk *pclk;
+	struct resource *res;
+	int ret;
+
+	dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
+	if (!dsi)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	dsi->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dsi->base)) {
+		ret = PTR_ERR(dsi->base);
+		DRM_ERROR("Unable to get dsi registers %d\n", ret);
+		return ret;
+	}
+
+	dsi->vdd_supply = devm_regulator_get(dev, "phy-dsi");
+	if (IS_ERR(dsi->vdd_supply)) {
+		ret = PTR_ERR(dsi->vdd_supply);
+		if (ret != -EPROBE_DEFER)
+			DRM_ERROR("Failed to request regulator: %d\n", ret);
+		return ret;
+	}
+
+	ret = regulator_enable(dsi->vdd_supply);
+	if (ret) {
+		DRM_ERROR("Failed to enable regulator: %d\n", ret);
+		return ret;
+	}
+
+	dsi->pllref_clk = devm_clk_get(dev, "ref");
+	if (IS_ERR(dsi->pllref_clk)) {
+		ret = PTR_ERR(dsi->pllref_clk);
+		if (ret != -EPROBE_DEFER)
+			DRM_ERROR("Unable to get pll reference clock: %d\n",
+				  ret);
+		goto err_clk_get;
+	}
+
+	ret = clk_prepare_enable(dsi->pllref_clk);
+	if (ret) {
+		DRM_ERROR("Failed to enable pllref_clk: %d\n", ret);
+		goto err_clk_get;
+	}
+
+	pclk = devm_clk_get(dev, "pclk");
+	if (IS_ERR(pclk)) {
+		ret = PTR_ERR(pclk);
+		DRM_ERROR("Unable to get peripheral clock: %d\n", ret);
+		goto err_dsi_probe;
+	}
+
+	ret = clk_prepare_enable(pclk);
+	if (ret) {
+		DRM_ERROR("%s: Failed to enable peripheral clk\n", __func__);
+		goto err_dsi_probe;
+	}
+
+	dsi->hw_version = dsi_read(dsi, DSI_VERSION) & VERSION;
+	clk_disable_unprepare(pclk);
+
+	if (dsi->hw_version != HWVER_130 && dsi->hw_version != HWVER_131) {
+		ret = -ENODEV;
+		DRM_ERROR("bad dsi hardware version\n");
+		goto err_dsi_probe;
+	}
+
+	dw_mipi_dsi_stm_plat_data.base = dsi->base;
+	dw_mipi_dsi_stm_plat_data.priv_data = dsi;
+
+	platform_set_drvdata(pdev, dsi);
+
+	dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
+	if (IS_ERR(dsi->dsi)) {
+		ret = PTR_ERR(dsi->dsi);
+		DRM_ERROR("Failed to initialize mipi dsi host: %d\n", ret);
+		goto err_dsi_probe;
+	}
+
+	return 0;
+
+err_dsi_probe:
+	clk_disable_unprepare(dsi->pllref_clk);
+err_clk_get:
+	regulator_disable(dsi->vdd_supply);
+
+	return ret;
+}
+
+static int dw_mipi_dsi_stm_remove(struct platform_device *pdev)
+{
+	struct dw_mipi_dsi_stm *dsi = platform_get_drvdata(pdev);
+
+	dw_mipi_dsi_remove(dsi->dsi);
+	clk_disable_unprepare(dsi->pllref_clk);
+	regulator_disable(dsi->vdd_supply);
+
+	return 0;
+}
+
+static int __maybe_unused dw_mipi_dsi_stm_suspend(struct device *dev)
+{
+	struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	clk_disable_unprepare(dsi->pllref_clk);
+	regulator_disable(dsi->vdd_supply);
+
+	return 0;
+}
+
+static int __maybe_unused dw_mipi_dsi_stm_resume(struct device *dev)
+{
+	struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
+	int ret;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	ret = regulator_enable(dsi->vdd_supply);
+	if (ret) {
+		DRM_ERROR("Failed to enable regulator: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(dsi->pllref_clk);
+	if (ret) {
+		regulator_disable(dsi->vdd_supply);
+		DRM_ERROR("Failed to enable pllref_clk: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct dev_pm_ops dw_mipi_dsi_stm_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(dw_mipi_dsi_stm_suspend,
+				dw_mipi_dsi_stm_resume)
+};
+
+static struct platform_driver dw_mipi_dsi_stm_driver = {
+	.probe		= dw_mipi_dsi_stm_probe,
+	.remove		= dw_mipi_dsi_stm_remove,
+	.driver		= {
+		.of_match_table = dw_mipi_dsi_stm_dt_ids,
+		.name	= "stm32-display-dsi",
+		.pm = &dw_mipi_dsi_stm_pm_ops,
+	},
+};
+
+module_platform_driver(dw_mipi_dsi_stm_driver);
+
+MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics DW MIPI DSI host controller driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
new file mode 100644
index 000000000..089c00a8e
--- /dev/null
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -0,0 +1,1390 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          Mickael Reulier <mickael.reulier@st.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_graph.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_device.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_plane_helper.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_vblank.h>
+
+#include <video/videomode.h>
+
+#include "ltdc.h"
+
+#define NB_CRTC 1
+#define CRTC_MASK GENMASK(NB_CRTC - 1, 0)
+
+#define MAX_IRQ 4
+
+#define HWVER_10200 0x010200
+#define HWVER_10300 0x010300
+#define HWVER_20101 0x020101
+
+/*
+ * The address of some registers depends on the HW version: such registers have
+ * an extra offset specified with reg_ofs.
+ */
+#define REG_OFS_NONE	0
+#define REG_OFS_4	4		/* Insertion of "Layer Conf. 2" reg */
+#define REG_OFS		(ldev->caps.reg_ofs)
+#define LAY_OFS		0x80		/* Register Offset between 2 layers */
+
+/* Global register offsets */
+#define LTDC_IDR	0x0000		/* IDentification */
+#define LTDC_LCR	0x0004		/* Layer Count */
+#define LTDC_SSCR	0x0008		/* Synchronization Size Configuration */
+#define LTDC_BPCR	0x000C		/* Back Porch Configuration */
+#define LTDC_AWCR	0x0010		/* Active Width Configuration */
+#define LTDC_TWCR	0x0014		/* Total Width Configuration */
+#define LTDC_GCR	0x0018		/* Global Control */
+#define LTDC_GC1R	0x001C		/* Global Configuration 1 */
+#define LTDC_GC2R	0x0020		/* Global Configuration 2 */
+#define LTDC_SRCR	0x0024		/* Shadow Reload Configuration */
+#define LTDC_GACR	0x0028		/* GAmma Correction */
+#define LTDC_BCCR	0x002C		/* Background Color Configuration */
+#define LTDC_IER	0x0034		/* Interrupt Enable */
+#define LTDC_ISR	0x0038		/* Interrupt Status */
+#define LTDC_ICR	0x003C		/* Interrupt Clear */
+#define LTDC_LIPCR	0x0040		/* Line Interrupt Position Conf. */
+#define LTDC_CPSR	0x0044		/* Current Position Status */
+#define LTDC_CDSR	0x0048		/* Current Display Status */
+
+/* Layer register offsets */
+#define LTDC_L1LC1R	(0x80)		/* L1 Layer Configuration 1 */
+#define LTDC_L1LC2R	(0x84)		/* L1 Layer Configuration 2 */
+#define LTDC_L1CR	(0x84 + REG_OFS)/* L1 Control */
+#define LTDC_L1WHPCR	(0x88 + REG_OFS)/* L1 Window Hor Position Config */
+#define LTDC_L1WVPCR	(0x8C + REG_OFS)/* L1 Window Vert Position Config */
+#define LTDC_L1CKCR	(0x90 + REG_OFS)/* L1 Color Keying Configuration */
+#define LTDC_L1PFCR	(0x94 + REG_OFS)/* L1 Pixel Format Configuration */
+#define LTDC_L1CACR	(0x98 + REG_OFS)/* L1 Constant Alpha Config */
+#define LTDC_L1DCCR	(0x9C + REG_OFS)/* L1 Default Color Configuration */
+#define LTDC_L1BFCR	(0xA0 + REG_OFS)/* L1 Blend Factors Configuration */
+#define LTDC_L1FBBCR	(0xA4 + REG_OFS)/* L1 FrameBuffer Bus Control */
+#define LTDC_L1AFBCR	(0xA8 + REG_OFS)/* L1 AuxFB Control */
+#define LTDC_L1CFBAR	(0xAC + REG_OFS)/* L1 Color FrameBuffer Address */
+#define LTDC_L1CFBLR	(0xB0 + REG_OFS)/* L1 Color FrameBuffer Length */
+#define LTDC_L1CFBLNR	(0xB4 + REG_OFS)/* L1 Color FrameBuffer Line Nb */
+#define LTDC_L1AFBAR	(0xB8 + REG_OFS)/* L1 AuxFB Address */
+#define LTDC_L1AFBLR	(0xBC + REG_OFS)/* L1 AuxFB Length */
+#define LTDC_L1AFBLNR	(0xC0 + REG_OFS)/* L1 AuxFB Line Number */
+#define LTDC_L1CLUTWR	(0xC4 + REG_OFS)/* L1 CLUT Write */
+#define LTDC_L1YS1R	(0xE0 + REG_OFS)/* L1 YCbCr Scale 1 */
+#define LTDC_L1YS2R	(0xE4 + REG_OFS)/* L1 YCbCr Scale 2 */
+
+/* Bit definitions */
+#define SSCR_VSH	GENMASK(10, 0)	/* Vertical Synchronization Height */
+#define SSCR_HSW	GENMASK(27, 16)	/* Horizontal Synchronization Width */
+
+#define BPCR_AVBP	GENMASK(10, 0)	/* Accumulated Vertical Back Porch */
+#define BPCR_AHBP	GENMASK(27, 16)	/* Accumulated Horizontal Back Porch */
+
+#define AWCR_AAH	GENMASK(10, 0)	/* Accumulated Active Height */
+#define AWCR_AAW	GENMASK(27, 16)	/* Accumulated Active Width */
+
+#define TWCR_TOTALH	GENMASK(10, 0)	/* TOTAL Height */
+#define TWCR_TOTALW	GENMASK(27, 16)	/* TOTAL Width */
+
+#define GCR_LTDCEN	BIT(0)		/* LTDC ENable */
+#define GCR_DEN		BIT(16)		/* Dither ENable */
+#define GCR_PCPOL	BIT(28)		/* Pixel Clock POLarity-Inverted */
+#define GCR_DEPOL	BIT(29)		/* Data Enable POLarity-High */
+#define GCR_VSPOL	BIT(30)		/* Vertical Synchro POLarity-High */
+#define GCR_HSPOL	BIT(31)		/* Horizontal Synchro POLarity-High */
+
+#define GC1R_WBCH	GENMASK(3, 0)	/* Width of Blue CHannel output */
+#define GC1R_WGCH	GENMASK(7, 4)	/* Width of Green Channel output */
+#define GC1R_WRCH	GENMASK(11, 8)	/* Width of Red Channel output */
+#define GC1R_PBEN	BIT(12)		/* Precise Blending ENable */
+#define GC1R_DT		GENMASK(15, 14)	/* Dithering Technique */
+#define GC1R_GCT	GENMASK(19, 17)	/* Gamma Correction Technique */
+#define GC1R_SHREN	BIT(21)		/* SHadow Registers ENabled */
+#define GC1R_BCP	BIT(22)		/* Background Colour Programmable */
+#define GC1R_BBEN	BIT(23)		/* Background Blending ENabled */
+#define GC1R_LNIP	BIT(24)		/* Line Number IRQ Position */
+#define GC1R_TP		BIT(25)		/* Timing Programmable */
+#define GC1R_IPP	BIT(26)		/* IRQ Polarity Programmable */
+#define GC1R_SPP	BIT(27)		/* Sync Polarity Programmable */
+#define GC1R_DWP	BIT(28)		/* Dither Width Programmable */
+#define GC1R_STREN	BIT(29)		/* STatus Registers ENabled */
+#define GC1R_BMEN	BIT(31)		/* Blind Mode ENabled */
+
+#define GC2R_EDCA	BIT(0)		/* External Display Control Ability  */
+#define GC2R_STSAEN	BIT(1)		/* Slave Timing Sync Ability ENabled */
+#define GC2R_DVAEN	BIT(2)		/* Dual-View Ability ENabled */
+#define GC2R_DPAEN	BIT(3)		/* Dual-Port Ability ENabled */
+#define GC2R_BW		GENMASK(6, 4)	/* Bus Width (log2 of nb of bytes) */
+#define GC2R_EDCEN	BIT(7)		/* External Display Control ENabled */
+
+#define SRCR_IMR	BIT(0)		/* IMmediate Reload */
+#define SRCR_VBR	BIT(1)		/* Vertical Blanking Reload */
+
+#define BCCR_BCBLACK	0x00		/* Background Color BLACK */
+#define BCCR_BCBLUE	GENMASK(7, 0)	/* Background Color BLUE */
+#define BCCR_BCGREEN	GENMASK(15, 8)	/* Background Color GREEN */
+#define BCCR_BCRED	GENMASK(23, 16)	/* Background Color RED */
+#define BCCR_BCWHITE	GENMASK(23, 0)	/* Background Color WHITE */
+
+#define IER_LIE		BIT(0)		/* Line Interrupt Enable */
+#define IER_FUIE	BIT(1)		/* Fifo Underrun Interrupt Enable */
+#define IER_TERRIE	BIT(2)		/* Transfer ERRor Interrupt Enable */
+#define IER_RRIE	BIT(3)		/* Register Reload Interrupt enable */
+
+#define CPSR_CYPOS	GENMASK(15, 0)	/* Current Y position */
+
+#define ISR_LIF		BIT(0)		/* Line Interrupt Flag */
+#define ISR_FUIF	BIT(1)		/* Fifo Underrun Interrupt Flag */
+#define ISR_TERRIF	BIT(2)		/* Transfer ERRor Interrupt Flag */
+#define ISR_RRIF	BIT(3)		/* Register Reload Interrupt Flag */
+
+#define LXCR_LEN	BIT(0)		/* Layer ENable */
+#define LXCR_COLKEN	BIT(1)		/* Color Keying Enable */
+#define LXCR_CLUTEN	BIT(4)		/* Color Look-Up Table ENable */
+
+#define LXWHPCR_WHSTPOS	GENMASK(11, 0)	/* Window Horizontal StarT POSition */
+#define LXWHPCR_WHSPPOS	GENMASK(27, 16)	/* Window Horizontal StoP POSition */
+
+#define LXWVPCR_WVSTPOS	GENMASK(10, 0)	/* Window Vertical StarT POSition */
+#define LXWVPCR_WVSPPOS	GENMASK(26, 16)	/* Window Vertical StoP POSition */
+
+#define LXPFCR_PF	GENMASK(2, 0)	/* Pixel Format */
+
+#define LXCACR_CONSTA	GENMASK(7, 0)	/* CONSTant Alpha */
+
+#define LXBFCR_BF2	GENMASK(2, 0)	/* Blending Factor 2 */
+#define LXBFCR_BF1	GENMASK(10, 8)	/* Blending Factor 1 */
+
+#define LXCFBLR_CFBLL	GENMASK(12, 0)	/* Color Frame Buffer Line Length */
+#define LXCFBLR_CFBP	GENMASK(28, 16)	/* Color Frame Buffer Pitch in bytes */
+
+#define LXCFBLNR_CFBLN	GENMASK(10, 0)	/* Color Frame Buffer Line Number */
+
+#define CLUT_SIZE	256
+
+#define CONSTA_MAX	0xFF		/* CONSTant Alpha MAX= 1.0 */
+#define BF1_PAXCA	0x600		/* Pixel Alpha x Constant Alpha */
+#define BF1_CA		0x400		/* Constant Alpha */
+#define BF2_1PAXCA	0x007		/* 1 - (Pixel Alpha x Constant Alpha) */
+#define BF2_1CA		0x005		/* 1 - Constant Alpha */
+
+#define NB_PF		8		/* Max nb of HW pixel format */
+
+enum ltdc_pix_fmt {
+	PF_NONE,
+	/* RGB formats */
+	PF_ARGB8888,		/* ARGB [32 bits] */
+	PF_RGBA8888,		/* RGBA [32 bits] */
+	PF_RGB888,		/* RGB [24 bits] */
+	PF_RGB565,		/* RGB [16 bits] */
+	PF_ARGB1555,		/* ARGB A:1 bit RGB:15 bits [16 bits] */
+	PF_ARGB4444,		/* ARGB A:4 bits R/G/B: 4 bits each [16 bits] */
+	/* Indexed formats */
+	PF_L8,			/* Indexed 8 bits [8 bits] */
+	PF_AL44,		/* Alpha:4 bits + indexed 4 bits [8 bits] */
+	PF_AL88			/* Alpha:8 bits + indexed 8 bits [16 bits] */
+};
+
+/* The index gives the encoding of the pixel format for an HW version */
+static const enum ltdc_pix_fmt ltdc_pix_fmt_a0[NB_PF] = {
+	PF_ARGB8888,		/* 0x00 */
+	PF_RGB888,		/* 0x01 */
+	PF_RGB565,		/* 0x02 */
+	PF_ARGB1555,		/* 0x03 */
+	PF_ARGB4444,		/* 0x04 */
+	PF_L8,			/* 0x05 */
+	PF_AL44,		/* 0x06 */
+	PF_AL88			/* 0x07 */
+};
+
+static const enum ltdc_pix_fmt ltdc_pix_fmt_a1[NB_PF] = {
+	PF_ARGB8888,		/* 0x00 */
+	PF_RGB888,		/* 0x01 */
+	PF_RGB565,		/* 0x02 */
+	PF_RGBA8888,		/* 0x03 */
+	PF_AL44,		/* 0x04 */
+	PF_L8,			/* 0x05 */
+	PF_ARGB1555,		/* 0x06 */
+	PF_ARGB4444		/* 0x07 */
+};
+
+static const u64 ltdc_format_modifiers[] = {
+	DRM_FORMAT_MOD_LINEAR,
+	DRM_FORMAT_MOD_INVALID
+};
+
+static inline u32 reg_read(void __iomem *base, u32 reg)
+{
+	return readl_relaxed(base + reg);
+}
+
+static inline void reg_write(void __iomem *base, u32 reg, u32 val)
+{
+	writel_relaxed(val, base + reg);
+}
+
+static inline void reg_set(void __iomem *base, u32 reg, u32 mask)
+{
+	reg_write(base, reg, reg_read(base, reg) | mask);
+}
+
+static inline void reg_clear(void __iomem *base, u32 reg, u32 mask)
+{
+	reg_write(base, reg, reg_read(base, reg) & ~mask);
+}
+
+static inline void reg_update_bits(void __iomem *base, u32 reg, u32 mask,
+				   u32 val)
+{
+	reg_write(base, reg, (reg_read(base, reg) & ~mask) | val);
+}
+
+static inline struct ltdc_device *crtc_to_ltdc(struct drm_crtc *crtc)
+{
+	return (struct ltdc_device *)crtc->dev->dev_private;
+}
+
+static inline struct ltdc_device *plane_to_ltdc(struct drm_plane *plane)
+{
+	return (struct ltdc_device *)plane->dev->dev_private;
+}
+
+static inline struct ltdc_device *encoder_to_ltdc(struct drm_encoder *enc)
+{
+	return (struct ltdc_device *)enc->dev->dev_private;
+}
+
+static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
+{
+	enum ltdc_pix_fmt pf;
+
+	switch (drm_fmt) {
+	case DRM_FORMAT_ARGB8888:
+	case DRM_FORMAT_XRGB8888:
+		pf = PF_ARGB8888;
+		break;
+	case DRM_FORMAT_RGBA8888:
+	case DRM_FORMAT_RGBX8888:
+		pf = PF_RGBA8888;
+		break;
+	case DRM_FORMAT_RGB888:
+		pf = PF_RGB888;
+		break;
+	case DRM_FORMAT_RGB565:
+		pf = PF_RGB565;
+		break;
+	case DRM_FORMAT_ARGB1555:
+	case DRM_FORMAT_XRGB1555:
+		pf = PF_ARGB1555;
+		break;
+	case DRM_FORMAT_ARGB4444:
+	case DRM_FORMAT_XRGB4444:
+		pf = PF_ARGB4444;
+		break;
+	case DRM_FORMAT_C8:
+		pf = PF_L8;
+		break;
+	default:
+		pf = PF_NONE;
+		break;
+		/* Note: There are no DRM_FORMAT for AL44 and AL88 */
+	}
+
+	return pf;
+}
+
+static inline u32 to_drm_pixelformat(enum ltdc_pix_fmt pf)
+{
+	switch (pf) {
+	case PF_ARGB8888:
+		return DRM_FORMAT_ARGB8888;
+	case PF_RGBA8888:
+		return DRM_FORMAT_RGBA8888;
+	case PF_RGB888:
+		return DRM_FORMAT_RGB888;
+	case PF_RGB565:
+		return DRM_FORMAT_RGB565;
+	case PF_ARGB1555:
+		return DRM_FORMAT_ARGB1555;
+	case PF_ARGB4444:
+		return DRM_FORMAT_ARGB4444;
+	case PF_L8:
+		return DRM_FORMAT_C8;
+	case PF_AL44:		/* No DRM support */
+	case PF_AL88:		/* No DRM support */
+	case PF_NONE:
+	default:
+		return 0;
+	}
+}
+
+static inline u32 get_pixelformat_without_alpha(u32 drm)
+{
+	switch (drm) {
+	case DRM_FORMAT_ARGB4444:
+		return DRM_FORMAT_XRGB4444;
+	case DRM_FORMAT_RGBA4444:
+		return DRM_FORMAT_RGBX4444;
+	case DRM_FORMAT_ARGB1555:
+		return DRM_FORMAT_XRGB1555;
+	case DRM_FORMAT_RGBA5551:
+		return DRM_FORMAT_RGBX5551;
+	case DRM_FORMAT_ARGB8888:
+		return DRM_FORMAT_XRGB8888;
+	case DRM_FORMAT_RGBA8888:
+		return DRM_FORMAT_RGBX8888;
+	default:
+		return 0;
+	}
+}
+
+static irqreturn_t ltdc_irq_thread(int irq, void *arg)
+{
+	struct drm_device *ddev = arg;
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct drm_crtc *crtc = drm_crtc_from_index(ddev, 0);
+
+	/* Line IRQ : trigger the vblank event */
+	if (ldev->irq_status & ISR_LIF)
+		drm_crtc_handle_vblank(crtc);
+
+	/* Save FIFO Underrun & Transfer Error status */
+	mutex_lock(&ldev->err_lock);
+	if (ldev->irq_status & ISR_FUIF)
+		ldev->error_status |= ISR_FUIF;
+	if (ldev->irq_status & ISR_TERRIF)
+		ldev->error_status |= ISR_TERRIF;
+	mutex_unlock(&ldev->err_lock);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t ltdc_irq(int irq, void *arg)
+{
+	struct drm_device *ddev = arg;
+	struct ltdc_device *ldev = ddev->dev_private;
+
+	/* Read & Clear the interrupt status */
+	ldev->irq_status = reg_read(ldev->regs, LTDC_ISR);
+	reg_write(ldev->regs, LTDC_ICR, ldev->irq_status);
+
+	return IRQ_WAKE_THREAD;
+}
+
+/*
+ * DRM_CRTC
+ */
+
+static void ltdc_crtc_update_clut(struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_color_lut *lut;
+	u32 val;
+	int i;
+
+	if (!crtc->state->color_mgmt_changed || !crtc->state->gamma_lut)
+		return;
+
+	lut = (struct drm_color_lut *)crtc->state->gamma_lut->data;
+
+	for (i = 0; i < CLUT_SIZE; i++, lut++) {
+		val = ((lut->red << 8) & 0xff0000) | (lut->green & 0xff00) |
+			(lut->blue >> 8) | (i << 24);
+		reg_write(ldev->regs, LTDC_L1CLUTWR, val);
+	}
+}
+
+static void ltdc_crtc_atomic_enable(struct drm_crtc *crtc,
+				    struct drm_crtc_state *old_state)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_device *ddev = crtc->dev;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	pm_runtime_get_sync(ddev->dev);
+
+	/* Sets the background color value */
+	reg_write(ldev->regs, LTDC_BCCR, BCCR_BCBLACK);
+
+	/* Enable IRQ */
+	reg_set(ldev->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
+
+	/* Commit shadow registers = update planes at next vblank */
+	reg_set(ldev->regs, LTDC_SRCR, SRCR_VBR);
+
+	drm_crtc_vblank_on(crtc);
+}
+
+static void ltdc_crtc_atomic_disable(struct drm_crtc *crtc,
+				     struct drm_crtc_state *old_state)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_device *ddev = crtc->dev;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	drm_crtc_vblank_off(crtc);
+
+	/* disable IRQ */
+	reg_clear(ldev->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
+
+	/* immediately commit disable of layers before switching off LTDC */
+	reg_set(ldev->regs, LTDC_SRCR, SRCR_IMR);
+
+	pm_runtime_put_sync(ddev->dev);
+}
+
+#define CLK_TOLERANCE_HZ 50
+
+static enum drm_mode_status
+ltdc_crtc_mode_valid(struct drm_crtc *crtc,
+		     const struct drm_display_mode *mode)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	int target = mode->clock * 1000;
+	int target_min = target - CLK_TOLERANCE_HZ;
+	int target_max = target + CLK_TOLERANCE_HZ;
+	int result;
+
+	result = clk_round_rate(ldev->pixel_clk, target);
+
+	DRM_DEBUG_DRIVER("clk rate target %d, available %d\n", target, result);
+
+	/* Filter modes according to the max frequency supported by the pads */
+	if (result > ldev->caps.pad_max_freq_hz)
+		return MODE_CLOCK_HIGH;
+
+	/*
+	 * Accept all "preferred" modes:
+	 * - this is important for panels because panel clock tolerances are
+	 *   bigger than hdmi ones and there is no reason to not accept them
+	 *   (the fps may vary a little but it is not a problem).
+	 * - the hdmi preferred mode will be accepted too, but userland will
+	 *   be able to use others hdmi "valid" modes if necessary.
+	 */
+	if (mode->type & DRM_MODE_TYPE_PREFERRED)
+		return MODE_OK;
+
+	/*
+	 * Filter modes according to the clock value, particularly useful for
+	 * hdmi modes that require precise pixel clocks.
+	 */
+	if (result < target_min || result > target_max)
+		return MODE_CLOCK_RANGE;
+
+	return MODE_OK;
+}
+
+static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
+				 const struct drm_display_mode *mode,
+				 struct drm_display_mode *adjusted_mode)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	int rate = mode->clock * 1000;
+
+	if (clk_set_rate(ldev->pixel_clk, rate) < 0) {
+		DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate);
+		return false;
+	}
+
+	adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000;
+
+	DRM_DEBUG_DRIVER("requested clock %dkHz, adjusted clock %dkHz\n",
+			 mode->clock, adjusted_mode->clock);
+
+	return true;
+}
+
+static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_device *ddev = crtc->dev;
+	struct drm_connector_list_iter iter;
+	struct drm_connector *connector = NULL;
+	struct drm_encoder *encoder = NULL, *en_iter;
+	struct drm_bridge *bridge = NULL, *br_iter;
+	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
+	struct videomode vm;
+	u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h;
+	u32 total_width, total_height;
+	u32 bus_flags = 0;
+	u32 val;
+	int ret;
+
+	/* get encoder from crtc */
+	drm_for_each_encoder(en_iter, ddev)
+		if (en_iter->crtc == crtc) {
+			encoder = en_iter;
+			break;
+		}
+
+	if (encoder) {
+		/* get bridge from encoder */
+		list_for_each_entry(br_iter, &encoder->bridge_chain, chain_node)
+			if (br_iter->encoder == encoder) {
+				bridge = br_iter;
+				break;
+			}
+
+		/* Get the connector from encoder */
+		drm_connector_list_iter_begin(ddev, &iter);
+		drm_for_each_connector_iter(connector, &iter)
+			if (connector->encoder == encoder)
+				break;
+		drm_connector_list_iter_end(&iter);
+	}
+
+	if (bridge && bridge->timings)
+		bus_flags = bridge->timings->input_bus_flags;
+	else if (connector)
+		bus_flags = connector->display_info.bus_flags;
+
+	if (!pm_runtime_active(ddev->dev)) {
+		ret = pm_runtime_get_sync(ddev->dev);
+		if (ret) {
+			DRM_ERROR("Failed to set mode, cannot get sync\n");
+			return;
+		}
+	}
+
+	drm_display_mode_to_videomode(mode, &vm);
+
+	DRM_DEBUG_DRIVER("CRTC:%d mode:%s\n", crtc->base.id, mode->name);
+	DRM_DEBUG_DRIVER("Video mode: %dx%d", vm.hactive, vm.vactive);
+	DRM_DEBUG_DRIVER(" hfp %d hbp %d hsl %d vfp %d vbp %d vsl %d\n",
+			 vm.hfront_porch, vm.hback_porch, vm.hsync_len,
+			 vm.vfront_porch, vm.vback_porch, vm.vsync_len);
+
+	/* Convert video timings to ltdc timings */
+	hsync = vm.hsync_len - 1;
+	vsync = vm.vsync_len - 1;
+	accum_hbp = hsync + vm.hback_porch;
+	accum_vbp = vsync + vm.vback_porch;
+	accum_act_w = accum_hbp + vm.hactive;
+	accum_act_h = accum_vbp + vm.vactive;
+	total_width = accum_act_w + vm.hfront_porch;
+	total_height = accum_act_h + vm.vfront_porch;
+
+	/* Configures the HS, VS, DE and PC polarities. Default Active Low */
+	val = 0;
+
+	if (vm.flags & DISPLAY_FLAGS_HSYNC_HIGH)
+		val |= GCR_HSPOL;
+
+	if (vm.flags & DISPLAY_FLAGS_VSYNC_HIGH)
+		val |= GCR_VSPOL;
+
+	if (bus_flags & DRM_BUS_FLAG_DE_LOW)
+		val |= GCR_DEPOL;
+
+	if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)
+		val |= GCR_PCPOL;
+
+	reg_update_bits(ldev->regs, LTDC_GCR,
+			GCR_HSPOL | GCR_VSPOL | GCR_DEPOL | GCR_PCPOL, val);
+
+	/* Set Synchronization size */
+	val = (hsync << 16) | vsync;
+	reg_update_bits(ldev->regs, LTDC_SSCR, SSCR_VSH | SSCR_HSW, val);
+
+	/* Set Accumulated Back porch */
+	val = (accum_hbp << 16) | accum_vbp;
+	reg_update_bits(ldev->regs, LTDC_BPCR, BPCR_AVBP | BPCR_AHBP, val);
+
+	/* Set Accumulated Active Width */
+	val = (accum_act_w << 16) | accum_act_h;
+	reg_update_bits(ldev->regs, LTDC_AWCR, AWCR_AAW | AWCR_AAH, val);
+
+	/* Set total width & height */
+	val = (total_width << 16) | total_height;
+	reg_update_bits(ldev->regs, LTDC_TWCR, TWCR_TOTALH | TWCR_TOTALW, val);
+
+	reg_write(ldev->regs, LTDC_LIPCR, (accum_act_h + 1));
+}
+
+static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc,
+				   struct drm_crtc_state *old_crtc_state)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_device *ddev = crtc->dev;
+	struct drm_pending_vblank_event *event = crtc->state->event;
+
+	DRM_DEBUG_ATOMIC("\n");
+
+	ltdc_crtc_update_clut(crtc);
+
+	/* Commit shadow registers = update planes at next vblank */
+	reg_set(ldev->regs, LTDC_SRCR, SRCR_VBR);
+
+	if (event) {
+		crtc->state->event = NULL;
+
+		spin_lock_irq(&ddev->event_lock);
+		if (drm_crtc_vblank_get(crtc) == 0)
+			drm_crtc_arm_vblank_event(crtc, event);
+		else
+			drm_crtc_send_vblank_event(crtc, event);
+		spin_unlock_irq(&ddev->event_lock);
+	}
+}
+
+static bool ltdc_crtc_get_scanout_position(struct drm_crtc *crtc,
+					   bool in_vblank_irq,
+					   int *vpos, int *hpos,
+					   ktime_t *stime, ktime_t *etime,
+					   const struct drm_display_mode *mode)
+{
+	struct drm_device *ddev = crtc->dev;
+	struct ltdc_device *ldev = ddev->dev_private;
+	int line, vactive_start, vactive_end, vtotal;
+
+	if (stime)
+		*stime = ktime_get();
+
+	/* The active area starts after vsync + front porch and ends
+	 * at vsync + front porc + display size.
+	 * The total height also include back porch.
+	 * We have 3 possible cases to handle:
+	 * - line < vactive_start: vpos = line - vactive_start and will be
+	 * negative
+	 * - vactive_start < line < vactive_end: vpos = line - vactive_start
+	 * and will be positive
+	 * - line > vactive_end: vpos = line - vtotal - vactive_start
+	 * and will negative
+	 *
+	 * Computation for the two first cases are identical so we can
+	 * simplify the code and only test if line > vactive_end
+	 */
+	if (pm_runtime_active(ddev->dev)) {
+		line = reg_read(ldev->regs, LTDC_CPSR) & CPSR_CYPOS;
+		vactive_start = reg_read(ldev->regs, LTDC_BPCR) & BPCR_AVBP;
+		vactive_end = reg_read(ldev->regs, LTDC_AWCR) & AWCR_AAH;
+		vtotal = reg_read(ldev->regs, LTDC_TWCR) & TWCR_TOTALH;
+
+		if (line > vactive_end)
+			*vpos = line - vtotal - vactive_start;
+		else
+			*vpos = line - vactive_start;
+	} else {
+		*vpos = 0;
+	}
+
+	*hpos = 0;
+
+	if (etime)
+		*etime = ktime_get();
+
+	return true;
+}
+
+static const struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = {
+	.mode_valid = ltdc_crtc_mode_valid,
+	.mode_fixup = ltdc_crtc_mode_fixup,
+	.mode_set_nofb = ltdc_crtc_mode_set_nofb,
+	.atomic_flush = ltdc_crtc_atomic_flush,
+	.atomic_enable = ltdc_crtc_atomic_enable,
+	.atomic_disable = ltdc_crtc_atomic_disable,
+	.get_scanout_position = ltdc_crtc_get_scanout_position,
+};
+
+static int ltdc_crtc_enable_vblank(struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_crtc_state *state = crtc->state;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	if (state->enable)
+		reg_set(ldev->regs, LTDC_IER, IER_LIE);
+	else
+		return -EPERM;
+
+	return 0;
+}
+
+static void ltdc_crtc_disable_vblank(struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+
+	DRM_DEBUG_DRIVER("\n");
+	reg_clear(ldev->regs, LTDC_IER, IER_LIE);
+}
+
+static const struct drm_crtc_funcs ltdc_crtc_funcs = {
+	.destroy = drm_crtc_cleanup,
+	.set_config = drm_atomic_helper_set_config,
+	.page_flip = drm_atomic_helper_page_flip,
+	.reset = drm_atomic_helper_crtc_reset,
+	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+	.enable_vblank = ltdc_crtc_enable_vblank,
+	.disable_vblank = ltdc_crtc_disable_vblank,
+	.get_vblank_timestamp = drm_crtc_vblank_helper_get_vblank_timestamp,
+	.gamma_set = drm_atomic_helper_legacy_gamma_set,
+};
+
+/*
+ * DRM_PLANE
+ */
+
+static int ltdc_plane_atomic_check(struct drm_plane *plane,
+				   struct drm_plane_state *state)
+{
+	struct drm_framebuffer *fb = state->fb;
+	u32 src_w, src_h;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	if (!fb)
+		return 0;
+
+	/* convert src_ from 16:16 format */
+	src_w = state->src_w >> 16;
+	src_h = state->src_h >> 16;
+
+	/* Reject scaling */
+	if (src_w != state->crtc_w || src_h != state->crtc_h) {
+		DRM_ERROR("Scaling is not supported");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void ltdc_plane_atomic_update(struct drm_plane *plane,
+				     struct drm_plane_state *oldstate)
+{
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	struct drm_plane_state *state = plane->state;
+	struct drm_framebuffer *fb = state->fb;
+	u32 lofs = plane->index * LAY_OFS;
+	u32 x0 = state->crtc_x;
+	u32 x1 = state->crtc_x + state->crtc_w - 1;
+	u32 y0 = state->crtc_y;
+	u32 y1 = state->crtc_y + state->crtc_h - 1;
+	u32 src_x, src_y, src_w, src_h;
+	u32 val, pitch_in_bytes, line_length, paddr, ahbp, avbp, bpcr;
+	enum ltdc_pix_fmt pf;
+
+	if (!state->crtc || !fb) {
+		DRM_DEBUG_DRIVER("fb or crtc NULL");
+		return;
+	}
+
+	/* convert src_ from 16:16 format */
+	src_x = state->src_x >> 16;
+	src_y = state->src_y >> 16;
+	src_w = state->src_w >> 16;
+	src_h = state->src_h >> 16;
+
+	DRM_DEBUG_DRIVER("plane:%d fb:%d (%dx%d)@(%d,%d) -> (%dx%d)@(%d,%d)\n",
+			 plane->base.id, fb->base.id,
+			 src_w, src_h, src_x, src_y,
+			 state->crtc_w, state->crtc_h,
+			 state->crtc_x, state->crtc_y);
+
+	bpcr = reg_read(ldev->regs, LTDC_BPCR);
+	ahbp = (bpcr & BPCR_AHBP) >> 16;
+	avbp = bpcr & BPCR_AVBP;
+
+	/* Configures the horizontal start and stop position */
+	val = ((x1 + 1 + ahbp) << 16) + (x0 + 1 + ahbp);
+	reg_update_bits(ldev->regs, LTDC_L1WHPCR + lofs,
+			LXWHPCR_WHSTPOS | LXWHPCR_WHSPPOS, val);
+
+	/* Configures the vertical start and stop position */
+	val = ((y1 + 1 + avbp) << 16) + (y0 + 1 + avbp);
+	reg_update_bits(ldev->regs, LTDC_L1WVPCR + lofs,
+			LXWVPCR_WVSTPOS | LXWVPCR_WVSPPOS, val);
+
+	/* Specifies the pixel format */
+	pf = to_ltdc_pixelformat(fb->format->format);
+	for (val = 0; val < NB_PF; val++)
+		if (ldev->caps.pix_fmt_hw[val] == pf)
+			break;
+
+	if (val == NB_PF) {
+		DRM_ERROR("Pixel format %.4s not supported\n",
+			  (char *)&fb->format->format);
+		val = 0;	/* set by default ARGB 32 bits */
+	}
+	reg_update_bits(ldev->regs, LTDC_L1PFCR + lofs, LXPFCR_PF, val);
+
+	/* Configures the color frame buffer pitch in bytes & line length */
+	pitch_in_bytes = fb->pitches[0];
+	line_length = fb->format->cpp[0] *
+		      (x1 - x0 + 1) + (ldev->caps.bus_width >> 3) - 1;
+	val = ((pitch_in_bytes << 16) | line_length);
+	reg_update_bits(ldev->regs, LTDC_L1CFBLR + lofs,
+			LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
+
+	/* Specifies the constant alpha value */
+	val = CONSTA_MAX;
+	reg_update_bits(ldev->regs, LTDC_L1CACR + lofs, LXCACR_CONSTA, val);
+
+	/* Specifies the blending factors */
+	val = BF1_PAXCA | BF2_1PAXCA;
+	if (!fb->format->has_alpha)
+		val = BF1_CA | BF2_1CA;
+
+	/* Manage hw-specific capabilities */
+	if (ldev->caps.non_alpha_only_l1 &&
+	    plane->type != DRM_PLANE_TYPE_PRIMARY)
+		val = BF1_PAXCA | BF2_1PAXCA;
+
+	reg_update_bits(ldev->regs, LTDC_L1BFCR + lofs,
+			LXBFCR_BF2 | LXBFCR_BF1, val);
+
+	/* Configures the frame buffer line number */
+	val = y1 - y0 + 1;
+	reg_update_bits(ldev->regs, LTDC_L1CFBLNR + lofs, LXCFBLNR_CFBLN, val);
+
+	/* Sets the FB address */
+	paddr = (u32)drm_fb_cma_get_gem_addr(fb, state, 0);
+
+	DRM_DEBUG_DRIVER("fb: phys 0x%08x", paddr);
+	reg_write(ldev->regs, LTDC_L1CFBAR + lofs, paddr);
+
+	/* Enable layer and CLUT if needed */
+	val = fb->format->format == DRM_FORMAT_C8 ? LXCR_CLUTEN : 0;
+	val |= LXCR_LEN;
+	reg_update_bits(ldev->regs, LTDC_L1CR + lofs,
+			LXCR_LEN | LXCR_CLUTEN, val);
+
+	ldev->plane_fpsi[plane->index].counter++;
+
+	mutex_lock(&ldev->err_lock);
+	if (ldev->error_status & ISR_FUIF) {
+		DRM_WARN("ltdc fifo underrun: please verify display mode\n");
+		ldev->error_status &= ~ISR_FUIF;
+	}
+	if (ldev->error_status & ISR_TERRIF) {
+		DRM_WARN("ltdc transfer error\n");
+		ldev->error_status &= ~ISR_TERRIF;
+	}
+	mutex_unlock(&ldev->err_lock);
+}
+
+static void ltdc_plane_atomic_disable(struct drm_plane *plane,
+				      struct drm_plane_state *oldstate)
+{
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	u32 lofs = plane->index * LAY_OFS;
+
+	/* disable layer */
+	reg_clear(ldev->regs, LTDC_L1CR + lofs, LXCR_LEN);
+
+	DRM_DEBUG_DRIVER("CRTC:%d plane:%d\n",
+			 oldstate->crtc->base.id, plane->base.id);
+}
+
+static void ltdc_plane_atomic_print_state(struct drm_printer *p,
+					  const struct drm_plane_state *state)
+{
+	struct drm_plane *plane = state->plane;
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	struct fps_info *fpsi = &ldev->plane_fpsi[plane->index];
+	int ms_since_last;
+	ktime_t now;
+
+	now = ktime_get();
+	ms_since_last = ktime_to_ms(ktime_sub(now, fpsi->last_timestamp));
+
+	drm_printf(p, "\tuser_updates=%dfps\n",
+		   DIV_ROUND_CLOSEST(fpsi->counter * 1000, ms_since_last));
+
+	fpsi->last_timestamp = now;
+	fpsi->counter = 0;
+}
+
+static bool ltdc_plane_format_mod_supported(struct drm_plane *plane,
+					    u32 format,
+					    u64 modifier)
+{
+	if (modifier == DRM_FORMAT_MOD_LINEAR)
+		return true;
+
+	return false;
+}
+
+static const struct drm_plane_funcs ltdc_plane_funcs = {
+	.update_plane = drm_atomic_helper_update_plane,
+	.disable_plane = drm_atomic_helper_disable_plane,
+	.destroy = drm_plane_cleanup,
+	.reset = drm_atomic_helper_plane_reset,
+	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
+	.atomic_print_state = ltdc_plane_atomic_print_state,
+	.format_mod_supported = ltdc_plane_format_mod_supported,
+};
+
+static const struct drm_plane_helper_funcs ltdc_plane_helper_funcs = {
+	.prepare_fb = drm_gem_fb_prepare_fb,
+	.atomic_check = ltdc_plane_atomic_check,
+	.atomic_update = ltdc_plane_atomic_update,
+	.atomic_disable = ltdc_plane_atomic_disable,
+};
+
+static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
+					   enum drm_plane_type type)
+{
+	unsigned long possible_crtcs = CRTC_MASK;
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct device *dev = ddev->dev;
+	struct drm_plane *plane;
+	unsigned int i, nb_fmt = 0;
+	u32 formats[NB_PF * 2];
+	u32 drm_fmt, drm_fmt_no_alpha;
+	const u64 *modifiers = ltdc_format_modifiers;
+	int ret;
+
+	/* Get supported pixel formats */
+	for (i = 0; i < NB_PF; i++) {
+		drm_fmt = to_drm_pixelformat(ldev->caps.pix_fmt_hw[i]);
+		if (!drm_fmt)
+			continue;
+		formats[nb_fmt++] = drm_fmt;
+
+		/* Add the no-alpha related format if any & supported */
+		drm_fmt_no_alpha = get_pixelformat_without_alpha(drm_fmt);
+		if (!drm_fmt_no_alpha)
+			continue;
+
+		/* Manage hw-specific capabilities */
+		if (ldev->caps.non_alpha_only_l1 &&
+		    type != DRM_PLANE_TYPE_PRIMARY)
+			continue;
+
+		formats[nb_fmt++] = drm_fmt_no_alpha;
+	}
+
+	plane = devm_kzalloc(dev, sizeof(*plane), GFP_KERNEL);
+	if (!plane)
+		return NULL;
+
+	ret = drm_universal_plane_init(ddev, plane, possible_crtcs,
+				       &ltdc_plane_funcs, formats, nb_fmt,
+				       modifiers, type, NULL);
+	if (ret < 0)
+		return NULL;
+
+	drm_plane_helper_add(plane, &ltdc_plane_helper_funcs);
+
+	DRM_DEBUG_DRIVER("plane:%d created\n", plane->base.id);
+
+	return plane;
+}
+
+static void ltdc_plane_destroy_all(struct drm_device *ddev)
+{
+	struct drm_plane *plane, *plane_temp;
+
+	list_for_each_entry_safe(plane, plane_temp,
+				 &ddev->mode_config.plane_list, head)
+		drm_plane_cleanup(plane);
+}
+
+static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct drm_plane *primary, *overlay;
+	unsigned int i;
+	int ret;
+
+	primary = ltdc_plane_create(ddev, DRM_PLANE_TYPE_PRIMARY);
+	if (!primary) {
+		DRM_ERROR("Can not create primary plane\n");
+		return -EINVAL;
+	}
+
+	ret = drm_crtc_init_with_planes(ddev, crtc, primary, NULL,
+					&ltdc_crtc_funcs, NULL);
+	if (ret) {
+		DRM_ERROR("Can not initialize CRTC\n");
+		goto cleanup;
+	}
+
+	drm_crtc_helper_add(crtc, &ltdc_crtc_helper_funcs);
+
+	drm_mode_crtc_set_gamma_size(crtc, CLUT_SIZE);
+	drm_crtc_enable_color_mgmt(crtc, 0, false, CLUT_SIZE);
+
+	DRM_DEBUG_DRIVER("CRTC:%d created\n", crtc->base.id);
+
+	/* Add planes. Note : the first layer is used by primary plane */
+	for (i = 1; i < ldev->caps.nb_layers; i++) {
+		overlay = ltdc_plane_create(ddev, DRM_PLANE_TYPE_OVERLAY);
+		if (!overlay) {
+			ret = -ENOMEM;
+			DRM_ERROR("Can not create overlay plane %d\n", i);
+			goto cleanup;
+		}
+	}
+
+	return 0;
+
+cleanup:
+	ltdc_plane_destroy_all(ddev);
+	return ret;
+}
+
+/*
+ * DRM_ENCODER
+ */
+
+static const struct drm_encoder_funcs ltdc_encoder_funcs = {
+	.destroy = drm_encoder_cleanup,
+};
+
+static void ltdc_encoder_disable(struct drm_encoder *encoder)
+{
+	struct drm_device *ddev = encoder->dev;
+	struct ltdc_device *ldev = ddev->dev_private;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Disable LTDC */
+	reg_clear(ldev->regs, LTDC_GCR, GCR_LTDCEN);
+
+	/* Set to sleep state the pinctrl whatever type of encoder */
+	pinctrl_pm_select_sleep_state(ddev->dev);
+}
+
+static void ltdc_encoder_enable(struct drm_encoder *encoder)
+{
+	struct drm_device *ddev = encoder->dev;
+	struct ltdc_device *ldev = ddev->dev_private;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Enable LTDC */
+	reg_set(ldev->regs, LTDC_GCR, GCR_LTDCEN);
+}
+
+static void ltdc_encoder_mode_set(struct drm_encoder *encoder,
+				  struct drm_display_mode *mode,
+				  struct drm_display_mode *adjusted_mode)
+{
+	struct drm_device *ddev = encoder->dev;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/*
+	 * Set to default state the pinctrl only with DPI type.
+	 * Others types like DSI, don't need pinctrl due to
+	 * internal bridge (the signals do not come out of the chipset).
+	 */
+	if (encoder->encoder_type == DRM_MODE_ENCODER_DPI)
+		pinctrl_pm_select_default_state(ddev->dev);
+}
+
+static const struct drm_encoder_helper_funcs ltdc_encoder_helper_funcs = {
+	.disable = ltdc_encoder_disable,
+	.enable = ltdc_encoder_enable,
+	.mode_set = ltdc_encoder_mode_set,
+};
+
+static int ltdc_encoder_init(struct drm_device *ddev, struct drm_bridge *bridge)
+{
+	struct drm_encoder *encoder;
+	int ret;
+
+	encoder = devm_kzalloc(ddev->dev, sizeof(*encoder), GFP_KERNEL);
+	if (!encoder)
+		return -ENOMEM;
+
+	encoder->possible_crtcs = CRTC_MASK;
+	encoder->possible_clones = 0;	/* No cloning support */
+
+	drm_encoder_init(ddev, encoder, &ltdc_encoder_funcs,
+			 DRM_MODE_ENCODER_DPI, NULL);
+
+	drm_encoder_helper_add(encoder, &ltdc_encoder_helper_funcs);
+
+	ret = drm_bridge_attach(encoder, bridge, NULL, 0);
+	if (ret) {
+		drm_encoder_cleanup(encoder);
+		return -EINVAL;
+	}
+
+	DRM_DEBUG_DRIVER("Bridge encoder:%d created\n", encoder->base.id);
+
+	return 0;
+}
+
+static int ltdc_get_caps(struct drm_device *ddev)
+{
+	struct ltdc_device *ldev = ddev->dev_private;
+	u32 bus_width_log2, lcr, gc2r;
+
+	/*
+	 * at least 1 layer must be managed & the number of layers
+	 * must not exceed LTDC_MAX_LAYER
+	 */
+	lcr = reg_read(ldev->regs, LTDC_LCR);
+
+	ldev->caps.nb_layers = clamp((int)lcr, 1, LTDC_MAX_LAYER);
+
+	/* set data bus width */
+	gc2r = reg_read(ldev->regs, LTDC_GC2R);
+	bus_width_log2 = (gc2r & GC2R_BW) >> 4;
+	ldev->caps.bus_width = 8 << bus_width_log2;
+	ldev->caps.hw_version = reg_read(ldev->regs, LTDC_IDR);
+
+	switch (ldev->caps.hw_version) {
+	case HWVER_10200:
+	case HWVER_10300:
+		ldev->caps.reg_ofs = REG_OFS_NONE;
+		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a0;
+		/*
+		 * Hw older versions support non-alpha color formats derived
+		 * from native alpha color formats only on the primary layer.
+		 * For instance, RG16 native format without alpha works fine
+		 * on 2nd layer but XR24 (derived color format from AR24)
+		 * does not work on 2nd layer.
+		 */
+		ldev->caps.non_alpha_only_l1 = true;
+		ldev->caps.pad_max_freq_hz = 90000000;
+		if (ldev->caps.hw_version == HWVER_10200)
+			ldev->caps.pad_max_freq_hz = 65000000;
+		ldev->caps.nb_irq = 2;
+		break;
+	case HWVER_20101:
+		ldev->caps.reg_ofs = REG_OFS_4;
+		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a1;
+		ldev->caps.non_alpha_only_l1 = false;
+		ldev->caps.pad_max_freq_hz = 150000000;
+		ldev->caps.nb_irq = 4;
+		break;
+	default:
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+void ltdc_suspend(struct drm_device *ddev)
+{
+	struct ltdc_device *ldev = ddev->dev_private;
+
+	DRM_DEBUG_DRIVER("\n");
+	clk_disable_unprepare(ldev->pixel_clk);
+}
+
+int ltdc_resume(struct drm_device *ddev)
+{
+	struct ltdc_device *ldev = ddev->dev_private;
+	int ret;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	ret = clk_prepare_enable(ldev->pixel_clk);
+	if (ret) {
+		DRM_ERROR("failed to enable pixel clock (%d)\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+int ltdc_load(struct drm_device *ddev)
+{
+	struct platform_device *pdev = to_platform_device(ddev->dev);
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct device *dev = ddev->dev;
+	struct device_node *np = dev->of_node;
+	struct drm_bridge *bridge;
+	struct drm_panel *panel;
+	struct drm_crtc *crtc;
+	struct reset_control *rstc;
+	struct resource *res;
+	int irq, i, nb_endpoints;
+	int ret = -ENODEV;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Get number of endpoints */
+	nb_endpoints = of_graph_get_endpoint_count(np);
+	if (!nb_endpoints)
+		return -ENODEV;
+
+	ldev->pixel_clk = devm_clk_get(dev, "lcd");
+	if (IS_ERR(ldev->pixel_clk)) {
+		if (PTR_ERR(ldev->pixel_clk) != -EPROBE_DEFER)
+			DRM_ERROR("Unable to get lcd clock\n");
+		return PTR_ERR(ldev->pixel_clk);
+	}
+
+	if (clk_prepare_enable(ldev->pixel_clk)) {
+		DRM_ERROR("Unable to prepare pixel clock\n");
+		return -ENODEV;
+	}
+
+	/* Get endpoints if any */
+	for (i = 0; i < nb_endpoints; i++) {
+		ret = drm_of_find_panel_or_bridge(np, 0, i, &panel, &bridge);
+
+		/*
+		 * If at least one endpoint is -ENODEV, continue probing,
+		 * else if at least one endpoint returned an error
+		 * (ie -EPROBE_DEFER) then stop probing.
+		 */
+		if (ret == -ENODEV)
+			continue;
+		else if (ret)
+			goto err;
+
+		if (panel) {
+			bridge = drm_panel_bridge_add_typed(panel,
+							    DRM_MODE_CONNECTOR_DPI);
+			if (IS_ERR(bridge)) {
+				DRM_ERROR("panel-bridge endpoint %d\n", i);
+				ret = PTR_ERR(bridge);
+				goto err;
+			}
+		}
+
+		if (bridge) {
+			ret = ltdc_encoder_init(ddev, bridge);
+			if (ret) {
+				DRM_ERROR("init encoder endpoint %d\n", i);
+				goto err;
+			}
+		}
+	}
+
+	rstc = devm_reset_control_get_exclusive(dev, NULL);
+
+	mutex_init(&ldev->err_lock);
+
+	if (!IS_ERR(rstc)) {
+		reset_control_assert(rstc);
+		usleep_range(10, 20);
+		reset_control_deassert(rstc);
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ldev->regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ldev->regs)) {
+		DRM_ERROR("Unable to get ltdc registers\n");
+		ret = PTR_ERR(ldev->regs);
+		goto err;
+	}
+
+	/* Disable interrupts */
+	reg_clear(ldev->regs, LTDC_IER,
+		  IER_LIE | IER_RRIE | IER_FUIE | IER_TERRIE);
+
+	ret = ltdc_get_caps(ddev);
+	if (ret) {
+		DRM_ERROR("hardware identifier (0x%08x) not supported!\n",
+			  ldev->caps.hw_version);
+		goto err;
+	}
+
+	DRM_DEBUG_DRIVER("ltdc hw version 0x%08x\n", ldev->caps.hw_version);
+
+	for (i = 0; i < ldev->caps.nb_irq; i++) {
+		irq = platform_get_irq(pdev, i);
+		if (irq < 0) {
+			ret = irq;
+			goto err;
+		}
+
+		ret = devm_request_threaded_irq(dev, irq, ltdc_irq,
+						ltdc_irq_thread, IRQF_ONESHOT,
+						dev_name(dev), ddev);
+		if (ret) {
+			DRM_ERROR("Failed to register LTDC interrupt\n");
+			goto err;
+		}
+
+	}
+
+	crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL);
+	if (!crtc) {
+		DRM_ERROR("Failed to allocate crtc\n");
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	ddev->mode_config.allow_fb_modifiers = true;
+
+	ret = ltdc_crtc_init(ddev, crtc);
+	if (ret) {
+		DRM_ERROR("Failed to init crtc\n");
+		goto err;
+	}
+
+	ret = drm_vblank_init(ddev, NB_CRTC);
+	if (ret) {
+		DRM_ERROR("Failed calling drm_vblank_init()\n");
+		goto err;
+	}
+
+	/* Allow usage of vblank without having to call drm_irq_install */
+	ddev->irq_enabled = 1;
+
+	clk_disable_unprepare(ldev->pixel_clk);
+
+	pinctrl_pm_select_sleep_state(ddev->dev);
+
+	pm_runtime_enable(ddev->dev);
+
+	return 0;
+err:
+	for (i = 0; i < nb_endpoints; i++)
+		drm_of_panel_bridge_remove(ddev->dev->of_node, 0, i);
+
+	clk_disable_unprepare(ldev->pixel_clk);
+
+	return ret;
+}
+
+void ltdc_unload(struct drm_device *ddev)
+{
+	struct device *dev = ddev->dev;
+	int nb_endpoints, i;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	nb_endpoints = of_graph_get_endpoint_count(dev->of_node);
+
+	for (i = 0; i < nb_endpoints; i++)
+		drm_of_panel_bridge_remove(ddev->dev->of_node, 0, i);
+
+	pm_runtime_disable(ddev->dev);
+}
+
+MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
+MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
+MODULE_AUTHOR("Mickael Reulier <mickael.reulier@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
new file mode 100644
index 000000000..f153b908c
--- /dev/null
+++ b/drivers/gpu/drm/stm/ltdc.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          Mickael Reulier <mickael.reulier@st.com>
+ */
+
+#ifndef _LTDC_H_
+#define _LTDC_H_
+
+struct ltdc_caps {
+	u32 hw_version;		/* hardware version */
+	u32 nb_layers;		/* number of supported layers */
+	u32 reg_ofs;		/* register offset for applicable regs */
+	u32 bus_width;		/* bus width (32 or 64 bits) */
+	const u32 *pix_fmt_hw;	/* supported pixel formats */
+	bool non_alpha_only_l1; /* non-native no-alpha formats on layer 1 */
+	int pad_max_freq_hz;	/* max frequency supported by pad */
+	int nb_irq;		/* number of hardware interrupts */
+};
+
+#define LTDC_MAX_LAYER	4
+
+struct fps_info {
+	unsigned int counter;
+	ktime_t last_timestamp;
+};
+
+struct ltdc_device {
+	void __iomem *regs;
+	struct clk *pixel_clk;	/* lcd pixel clock */
+	struct mutex err_lock;	/* protecting error_status */
+	struct ltdc_caps caps;
+	u32 error_status;
+	u32 irq_status;
+	struct fps_info plane_fpsi[LTDC_MAX_LAYER];
+	struct drm_atomic_state *suspend_state;
+};
+
+int ltdc_load(struct drm_device *ddev);
+void ltdc_unload(struct drm_device *ddev);
+void ltdc_suspend(struct drm_device *ddev);
+int ltdc_resume(struct drm_device *ddev);
+
+#endif