drm/sprd: add Unisoc's drm display controller driver

Adds DPU(Display Processor Unit) support for the Unisoc's display
subsystem.
It's support multi planes, scaler, rotation, PQ(Picture Quality) and more.

v2:
- Use drm_xxx to replace all DRM_XXX.
- Use kzalloc to replace devm_kzalloc for sprd_dpu structure init.

v3:
- Remove dpu_layer stuff layer and commit layers by aotmic_update

v4:
- Use drmm_helpers to allocate crtc and planes.
- Move rotation enum definitions to crtc layer reg bitfields.
- Move allocate crtc and planes to bind function.

v5:
- Fix the checkpatch warnings.
- Use mode_set_nofb instead of mode_valid callback.
- Follow the OF-Graph bindings, use of_graph_get_port_by_id
instead of of_parse_phandle.
- Use zpos to represent the layer position.
- Rebase to last drm misc branch.

v6:
- Disable and clear interrupts before register dpu IRQ
- Init dpi config used by crtc_state->adjusted_mode on mode_set_nofb
- Remove enable_irq and disable_irq function call.
- Remove drm_format_info function call.

v7:
- Remove iommu error interrupt handling function.

Cc: Orson Zhai <[e-mail]>
Cc: Chunyan Zhang <[e-mail]>
Signed-off-by: Kevin Tang <[e-mail]>
Reviewed-by: Maxime Ripard <[e-mail]>
Signed-off-by: Maarten Lankhorst <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/sprd/Kconfig

···
 	select DRM_GEM_CMA_HELPER
 	select DRM_KMS_CMA_HELPER
 	select DRM_KMS_HELPER
+	select VIDEOMODE_HELPERS
 	help
 	  Choose this option if you have a Unisoc chipset.
 	  If M is selected the module will be called sprd_drm.

drivers/gpu/drm/sprd/Makefile

···
 # SPDX-License-Identifier: GPL-2.0
 
-obj-y := sprd_drm.o
+obj-y := sprd_drm.o \
+	sprd_dpu.o

drivers/gpu/drm/sprd/sprd_dpu.c

···
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Unisoc Inc.
+ */
+
+#include <linux/component.h>
+#include <linux/delay.h>
+#include <linux/dma-buf.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/of_irq.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_plane_helper.h>
+
+#include "sprd_drm.h"
+#include "sprd_dpu.h"
+
+/* Global control registers */
+#define REG_DPU_CTRL	0x04
+#define REG_DPU_CFG0	0x08
+#define REG_PANEL_SIZE	0x20
+#define REG_BLEND_SIZE	0x24
+#define REG_BG_COLOR	0x2C
+
+/* Layer0 control registers */
+#define REG_LAY_BASE_ADDR0	0x30
+#define REG_LAY_BASE_ADDR1	0x34
+#define REG_LAY_BASE_ADDR2	0x38
+#define REG_LAY_CTRL		0x40
+#define REG_LAY_SIZE		0x44
+#define REG_LAY_PITCH		0x48
+#define REG_LAY_POS		0x4C
+#define REG_LAY_ALPHA		0x50
+#define REG_LAY_CROP_START	0x5C
+
+/* Interrupt control registers */
+#define REG_DPU_INT_EN		0x1E0
+#define REG_DPU_INT_CLR		0x1E4
+#define REG_DPU_INT_STS		0x1E8
+
+/* DPI control registers */
+#define REG_DPI_CTRL		0x1F0
+#define REG_DPI_H_TIMING	0x1F4
+#define REG_DPI_V_TIMING	0x1F8
+
+/* MMU control registers */
+#define REG_MMU_EN			0x800
+#define REG_MMU_VPN_RANGE		0x80C
+#define REG_MMU_PPN1			0x83C
+#define REG_MMU_RANGE1			0x840
+#define REG_MMU_PPN2			0x844
+#define REG_MMU_RANGE2			0x848
+
+/* Global control bits */
+#define BIT_DPU_RUN			BIT(0)
+#define BIT_DPU_STOP			BIT(1)
+#define BIT_DPU_REG_UPDATE		BIT(2)
+#define BIT_DPU_IF_EDPI			BIT(0)
+
+/* Layer control bits */
+#define BIT_DPU_LAY_EN				BIT(0)
+#define BIT_DPU_LAY_LAYER_ALPHA			(0x01 << 2)
+#define BIT_DPU_LAY_COMBO_ALPHA			(0x02 << 2)
+#define BIT_DPU_LAY_FORMAT_YUV422_2PLANE		(0x00 << 4)
+#define BIT_DPU_LAY_FORMAT_YUV420_2PLANE		(0x01 << 4)
+#define BIT_DPU_LAY_FORMAT_YUV420_3PLANE		(0x02 << 4)
+#define BIT_DPU_LAY_FORMAT_ARGB8888			(0x03 << 4)
+#define BIT_DPU_LAY_FORMAT_RGB565			(0x04 << 4)
+#define BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3		(0x00 << 8)
+#define BIT_DPU_LAY_DATA_ENDIAN_B3B2B1B0		(0x01 << 8)
+#define BIT_DPU_LAY_NO_SWITCH			(0x00 << 10)
+#define BIT_DPU_LAY_RB_OR_UV_SWITCH		(0x01 << 10)
+#define BIT_DPU_LAY_MODE_BLEND_NORMAL		(0x00 << 16)
+#define BIT_DPU_LAY_MODE_BLEND_PREMULT		(0x01 << 16)
+#define BIT_DPU_LAY_ROTATION_0		(0x00 << 20)
+#define BIT_DPU_LAY_ROTATION_90		(0x01 << 20)
+#define BIT_DPU_LAY_ROTATION_180	(0x02 << 20)
+#define BIT_DPU_LAY_ROTATION_270	(0x03 << 20)
+#define BIT_DPU_LAY_ROTATION_0_M	(0x04 << 20)
+#define BIT_DPU_LAY_ROTATION_90_M	(0x05 << 20)
+#define BIT_DPU_LAY_ROTATION_180_M	(0x06 << 20)
+#define BIT_DPU_LAY_ROTATION_270_M	(0x07 << 20)
+
+/* Interrupt control & status bits */
+#define BIT_DPU_INT_DONE		BIT(0)
+#define BIT_DPU_INT_TE			BIT(1)
+#define BIT_DPU_INT_ERR			BIT(2)
+#define BIT_DPU_INT_UPDATE_DONE		BIT(4)
+#define BIT_DPU_INT_VSYNC		BIT(5)
+
+/* DPI control bits */
+#define BIT_DPU_EDPI_TE_EN		BIT(8)
+#define BIT_DPU_EDPI_FROM_EXTERNAL_PAD	BIT(10)
+#define BIT_DPU_DPI_HALT_EN		BIT(16)
+
+static const u32 layer_fmts[] = {
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_XBGR8888,
+	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_ABGR8888,
+	DRM_FORMAT_RGBA8888,
+	DRM_FORMAT_BGRA8888,
+	DRM_FORMAT_RGBX8888,
+	DRM_FORMAT_RGB565,
+	DRM_FORMAT_BGR565,
+	DRM_FORMAT_NV12,
+	DRM_FORMAT_NV21,
+	DRM_FORMAT_NV16,
+	DRM_FORMAT_NV61,
+	DRM_FORMAT_YUV420,
+	DRM_FORMAT_YVU420,
+};
+
+struct sprd_plane {
+	struct drm_plane base;
+};
+
+static int dpu_wait_stop_done(struct sprd_dpu *dpu)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+	int rc;
+
+	if (ctx->stopped)
+		return 0;
+
+	rc = wait_event_interruptible_timeout(ctx->wait_queue, ctx->evt_stop,
+					      msecs_to_jiffies(500));
+	ctx->evt_stop = false;
+
+	ctx->stopped = true;
+
+	if (!rc) {
+		drm_err(dpu->drm, "dpu wait for stop done time out!\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int dpu_wait_update_done(struct sprd_dpu *dpu)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+	int rc;
+
+	ctx->evt_update = false;
+
+	rc = wait_event_interruptible_timeout(ctx->wait_queue, ctx->evt_update,
+					      msecs_to_jiffies(500));
+
+	if (!rc) {
+		drm_err(dpu->drm, "dpu wait for reg update done time out!\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static u32 drm_format_to_dpu(struct drm_framebuffer *fb)
+{
+	u32 format = 0;
+
+	switch (fb->format->format) {
+	case DRM_FORMAT_BGRA8888:
+		/* BGRA8888 -> ARGB8888 */
+		format |= BIT_DPU_LAY_DATA_ENDIAN_B3B2B1B0;
+		format |= BIT_DPU_LAY_FORMAT_ARGB8888;
+		break;
+	case DRM_FORMAT_RGBX8888:
+	case DRM_FORMAT_RGBA8888:
+		/* RGBA8888 -> ABGR8888 */
+		format |= BIT_DPU_LAY_DATA_ENDIAN_B3B2B1B0;
+		fallthrough;
+	case DRM_FORMAT_ABGR8888:
+		/* RB switch */
+		format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
+		fallthrough;
+	case DRM_FORMAT_ARGB8888:
+		format |= BIT_DPU_LAY_FORMAT_ARGB8888;
+		break;
+	case DRM_FORMAT_XBGR8888:
+		/* RB switch */
+		format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
+		fallthrough;
+	case DRM_FORMAT_XRGB8888:
+		format |= BIT_DPU_LAY_FORMAT_ARGB8888;
+		break;
+	case DRM_FORMAT_BGR565:
+		/* RB switch */
+		format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
+		fallthrough;
+	case DRM_FORMAT_RGB565:
+		format |= BIT_DPU_LAY_FORMAT_RGB565;
+		break;
+	case DRM_FORMAT_NV12:
+		/* 2-Lane: Yuv420 */
+		format |= BIT_DPU_LAY_FORMAT_YUV420_2PLANE;
+		/* Y endian */
+		format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
+		/* UV endian */
+		format |= BIT_DPU_LAY_NO_SWITCH;
+		break;
+	case DRM_FORMAT_NV21:
+		/* 2-Lane: Yuv420 */
+		format |= BIT_DPU_LAY_FORMAT_YUV420_2PLANE;
+		/* Y endian */
+		format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
+		/* UV endian */
+		format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
+		break;
+	case DRM_FORMAT_NV16:
+		/* 2-Lane: Yuv422 */
+		format |= BIT_DPU_LAY_FORMAT_YUV422_2PLANE;
+		/* Y endian */
+		format |= BIT_DPU_LAY_DATA_ENDIAN_B3B2B1B0;
+		/* UV endian */
+		format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
+		break;
+	case DRM_FORMAT_NV61:
+		/* 2-Lane: Yuv422 */
+		format |= BIT_DPU_LAY_FORMAT_YUV422_2PLANE;
+		/* Y endian */
+		format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
+		/* UV endian */
+		format |= BIT_DPU_LAY_NO_SWITCH;
+		break;
+	case DRM_FORMAT_YUV420:
+		format |= BIT_DPU_LAY_FORMAT_YUV420_3PLANE;
+		/* Y endian */
+		format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
+		/* UV endian */
+		format |= BIT_DPU_LAY_NO_SWITCH;
+		break;
+	case DRM_FORMAT_YVU420:
+		format |= BIT_DPU_LAY_FORMAT_YUV420_3PLANE;
+		/* Y endian */
+		format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
+		/* UV endian */
+		format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
+		break;
+	default:
+		break;
+	}
+
+	return format;
+}
+
+static u32 drm_rotation_to_dpu(struct drm_plane_state *state)
+{
+	u32 rotation = 0;
+
+	switch (state->rotation) {
+	default:
+	case DRM_MODE_ROTATE_0:
+		rotation = BIT_DPU_LAY_ROTATION_0;
+		break;
+	case DRM_MODE_ROTATE_90:
+		rotation = BIT_DPU_LAY_ROTATION_90;
+		break;
+	case DRM_MODE_ROTATE_180:
+		rotation = BIT_DPU_LAY_ROTATION_180;
+		break;
+	case DRM_MODE_ROTATE_270:
+		rotation = BIT_DPU_LAY_ROTATION_270;
+		break;
+	case DRM_MODE_REFLECT_Y:
+		rotation = BIT_DPU_LAY_ROTATION_180_M;
+		break;
+	case (DRM_MODE_REFLECT_Y | DRM_MODE_ROTATE_90):
+		rotation = BIT_DPU_LAY_ROTATION_90_M;
+		break;
+	case DRM_MODE_REFLECT_X:
+		rotation = BIT_DPU_LAY_ROTATION_0_M;
+		break;
+	case (DRM_MODE_REFLECT_X | DRM_MODE_ROTATE_90):
+		rotation = BIT_DPU_LAY_ROTATION_270_M;
+		break;
+	}
+
+	return rotation;
+}
+
+static u32 drm_blend_to_dpu(struct drm_plane_state *state)
+{
+	u32 blend = 0;
+
+	switch (state->pixel_blend_mode) {
+	case DRM_MODE_BLEND_COVERAGE:
+		/* alpha mode select - combo alpha */
+		blend |= BIT_DPU_LAY_COMBO_ALPHA;
+		/* Normal mode */
+		blend |= BIT_DPU_LAY_MODE_BLEND_NORMAL;
+		break;
+	case DRM_MODE_BLEND_PREMULTI:
+		/* alpha mode select - combo alpha */
+		blend |= BIT_DPU_LAY_COMBO_ALPHA;
+		/* Pre-mult mode */
+		blend |= BIT_DPU_LAY_MODE_BLEND_PREMULT;
+		break;
+	case DRM_MODE_BLEND_PIXEL_NONE:
+	default:
+		/* don't do blending, maybe RGBX */
+		/* alpha mode select - layer alpha */
+		blend |= BIT_DPU_LAY_LAYER_ALPHA;
+		break;
+	}
+
+	return blend;
+}
+
+static void sprd_dpu_layer(struct sprd_dpu *dpu, struct drm_plane_state *state)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+	struct drm_gem_cma_object *cma_obj;
+	struct drm_framebuffer *fb = state->fb;
+	u32 addr, size, offset, pitch, blend, format, rotation;
+	u32 src_x = state->src_x >> 16;
+	u32 src_y = state->src_y >> 16;
+	u32 src_w = state->src_w >> 16;
+	u32 src_h = state->src_h >> 16;
+	u32 dst_x = state->crtc_x;
+	u32 dst_y = state->crtc_y;
+	u32 alpha = state->alpha;
+	u32 index = state->zpos;
+	int i;
+
+	offset = (dst_x & 0xffff) | (dst_y << 16);
+	size = (src_w & 0xffff) | (src_h << 16);
+
+	for (i = 0; i < fb->format->num_planes; i++) {
+		cma_obj = drm_fb_cma_get_gem_obj(fb, i);
+		addr = cma_obj->paddr + fb->offsets[i];
+
+		if (i == 0)
+			layer_reg_wr(ctx, REG_LAY_BASE_ADDR0, addr, index);
+		else if (i == 1)
+			layer_reg_wr(ctx, REG_LAY_BASE_ADDR1, addr, index);
+		else
+			layer_reg_wr(ctx, REG_LAY_BASE_ADDR2, addr, index);
+	}
+
+	if (fb->format->num_planes == 3) {
+		/* UV pitch is 1/2 of Y pitch */
+		pitch = (fb->pitches[0] / fb->format->cpp[0]) |
+				(fb->pitches[0] / fb->format->cpp[0] << 15);
+	} else {
+		pitch = fb->pitches[0] / fb->format->cpp[0];
+	}
+
+	layer_reg_wr(ctx, REG_LAY_POS, offset, index);
+	layer_reg_wr(ctx, REG_LAY_SIZE, size, index);
+	layer_reg_wr(ctx, REG_LAY_CROP_START,
+		     src_y << 16 | src_x, index);
+	layer_reg_wr(ctx, REG_LAY_ALPHA, alpha, index);
+	layer_reg_wr(ctx, REG_LAY_PITCH, pitch, index);
+
+	format = drm_format_to_dpu(fb);
+	blend = drm_blend_to_dpu(state);
+	rotation = drm_rotation_to_dpu(state);
+
+	layer_reg_wr(ctx, REG_LAY_CTRL, BIT_DPU_LAY_EN |
+				format |
+				blend |
+				rotation,
+				index);
+}
+
+static void sprd_dpu_flip(struct sprd_dpu *dpu)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+
+	/*
+	 * Make sure the dpu is in stop status. DPU has no shadow
+	 * registers in EDPI mode. So the config registers can only be
+	 * updated in the rising edge of DPU_RUN bit.
+	 */
+	if (ctx->if_type == SPRD_DPU_IF_EDPI)
+		dpu_wait_stop_done(dpu);
+
+	/* update trigger and wait */
+	if (ctx->if_type == SPRD_DPU_IF_DPI) {
+		if (!ctx->stopped) {
+			dpu_reg_set(ctx, REG_DPU_CTRL, BIT_DPU_REG_UPDATE);
+			dpu_wait_update_done(dpu);
+		}
+
+		dpu_reg_set(ctx, REG_DPU_INT_EN, BIT_DPU_INT_ERR);
+	} else if (ctx->if_type == SPRD_DPU_IF_EDPI) {
+		dpu_reg_set(ctx, REG_DPU_CTRL, BIT_DPU_RUN);
+
+		ctx->stopped = false;
+	}
+}
+
+static void sprd_dpu_init(struct sprd_dpu *dpu)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+	u32 int_mask = 0;
+
+	writel(0x00, ctx->base + REG_BG_COLOR);
+	writel(0x00, ctx->base + REG_MMU_EN);
+	writel(0x00, ctx->base + REG_MMU_PPN1);
+	writel(0xffff, ctx->base + REG_MMU_RANGE1);
+	writel(0x00, ctx->base + REG_MMU_PPN2);
+	writel(0xffff, ctx->base + REG_MMU_RANGE2);
+	writel(0x1ffff, ctx->base + REG_MMU_VPN_RANGE);
+
+	if (ctx->if_type == SPRD_DPU_IF_DPI) {
+		/* use dpi as interface */
+		dpu_reg_clr(ctx, REG_DPU_CFG0, BIT_DPU_IF_EDPI);
+		/* disable Halt function for SPRD DSI */
+		dpu_reg_clr(ctx, REG_DPI_CTRL, BIT_DPU_DPI_HALT_EN);
+		/* select te from external pad */
+		dpu_reg_set(ctx, REG_DPI_CTRL, BIT_DPU_EDPI_FROM_EXTERNAL_PAD);
+
+		/* enable dpu update done INT */
+		int_mask |= BIT_DPU_INT_UPDATE_DONE;
+		/* enable dpu done INT */
+		int_mask |= BIT_DPU_INT_DONE;
+		/* enable dpu dpi vsync */
+		int_mask |= BIT_DPU_INT_VSYNC;
+		/* enable dpu TE INT */
+		int_mask |= BIT_DPU_INT_TE;
+		/* enable underflow err INT */
+		int_mask |= BIT_DPU_INT_ERR;
+	} else if (ctx->if_type == SPRD_DPU_IF_EDPI) {
+		/* use edpi as interface */
+		dpu_reg_set(ctx, REG_DPU_CFG0, BIT_DPU_IF_EDPI);
+		/* use external te */
+		dpu_reg_set(ctx, REG_DPI_CTRL, BIT_DPU_EDPI_FROM_EXTERNAL_PAD);
+		/* enable te */
+		dpu_reg_set(ctx, REG_DPI_CTRL, BIT_DPU_EDPI_TE_EN);
+
+		/* enable stop done INT */
+		int_mask |= BIT_DPU_INT_DONE;
+		/* enable TE INT */
+		int_mask |= BIT_DPU_INT_TE;
+	}
+
+	writel(int_mask, ctx->base + REG_DPU_INT_EN);
+}
+
+static void sprd_dpu_fini(struct sprd_dpu *dpu)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+
+	writel(0x00, ctx->base + REG_DPU_INT_EN);
+	writel(0xff, ctx->base + REG_DPU_INT_CLR);
+}
+
+static void sprd_dpi_init(struct sprd_dpu *dpu)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+	u32 reg_val;
+	u32 size;
+
+	size = (ctx->vm.vactive << 16) | ctx->vm.hactive;
+	writel(size, ctx->base + REG_PANEL_SIZE);
+	writel(size, ctx->base + REG_BLEND_SIZE);
+
+	if (ctx->if_type == SPRD_DPU_IF_DPI) {
+		/* set dpi timing */
+		reg_val = ctx->vm.hsync_len << 0 |
+			  ctx->vm.hback_porch << 8 |
+			  ctx->vm.hfront_porch << 20;
+		writel(reg_val, ctx->base + REG_DPI_H_TIMING);
+
+		reg_val = ctx->vm.vsync_len << 0 |
+			  ctx->vm.vback_porch << 8 |
+			  ctx->vm.vfront_porch << 20;
+		writel(reg_val, ctx->base + REG_DPI_V_TIMING);
+	}
+}
+
+void sprd_dpu_run(struct sprd_dpu *dpu)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+
+	dpu_reg_set(ctx, REG_DPU_CTRL, BIT_DPU_RUN);
+
+	ctx->stopped = false;
+}
+
+void sprd_dpu_stop(struct sprd_dpu *dpu)
+{
+	struct dpu_context *ctx = &dpu->ctx;
+
+	if (ctx->if_type == SPRD_DPU_IF_DPI)
+		dpu_reg_set(ctx, REG_DPU_CTRL, BIT_DPU_STOP);
+
+	dpu_wait_stop_done(dpu);
+}
+
+static int sprd_plane_atomic_check(struct drm_plane *plane,
+				   struct drm_atomic_state *state)
+{
+	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state,
+									     plane);
+	struct drm_crtc_state *crtc_state;
+	u32 fmt;
+
+	if (!plane_state->fb || !plane_state->crtc)
+		return 0;
+
+	fmt = drm_format_to_dpu(plane_state->fb);
+	if (!fmt)
+		return -EINVAL;
+
+	crtc_state = drm_atomic_get_crtc_state(plane_state->state, plane_state->crtc);
+	if (IS_ERR(crtc_state))
+		return PTR_ERR(crtc_state);
+
+	return drm_atomic_helper_check_plane_state(plane_state, crtc_state,
+						  DRM_PLANE_HELPER_NO_SCALING,
+						  DRM_PLANE_HELPER_NO_SCALING,
+						  true, true);
+}
+
+static void sprd_plane_atomic_update(struct drm_plane *drm_plane,
+				     struct drm_atomic_state *state)
+{
+	struct drm_plane_state *new_state = drm_atomic_get_new_plane_state(state,
+									   drm_plane);
+	struct sprd_dpu *dpu = to_sprd_crtc(new_state->crtc);
+
+	/* start configure dpu layers */
+	sprd_dpu_layer(dpu, new_state);
+}
+
+static void sprd_plane_atomic_disable(struct drm_plane *drm_plane,
+				      struct drm_atomic_state *state)
+{
+	struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state,
+									   drm_plane);
+	struct sprd_dpu *dpu = to_sprd_crtc(old_state->crtc);
+
+	layer_reg_wr(&dpu->ctx, REG_LAY_CTRL, 0x00, old_state->zpos);
+}
+
+static void sprd_plane_create_properties(struct sprd_plane *plane, int index)
+{
+	unsigned int supported_modes = BIT(DRM_MODE_BLEND_PIXEL_NONE) |
+				       BIT(DRM_MODE_BLEND_PREMULTI) |
+				       BIT(DRM_MODE_BLEND_COVERAGE);
+
+	/* create rotation property */
+	drm_plane_create_rotation_property(&plane->base,
+					   DRM_MODE_ROTATE_0,
+					   DRM_MODE_ROTATE_MASK |
+					   DRM_MODE_REFLECT_MASK);
+
+	/* create alpha property */
+	drm_plane_create_alpha_property(&plane->base);
+
+	/* create blend mode property */
+	drm_plane_create_blend_mode_property(&plane->base, supported_modes);
+
+	/* create zpos property */
+	drm_plane_create_zpos_immutable_property(&plane->base, index);
+}
+
+static const struct drm_plane_helper_funcs sprd_plane_helper_funcs = {
+	.atomic_check = sprd_plane_atomic_check,
+	.atomic_update = sprd_plane_atomic_update,
+	.atomic_disable = sprd_plane_atomic_disable,
+};
+
+static const struct drm_plane_funcs sprd_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,
+};
+
+static struct sprd_plane *sprd_planes_init(struct drm_device *drm)
+{
+	struct sprd_plane *plane, *primary;
+	enum drm_plane_type plane_type;
+	int i;
+
+	for (i = 0; i < 6; i++) {
+		plane_type = (i == 0) ? DRM_PLANE_TYPE_PRIMARY :
+					DRM_PLANE_TYPE_OVERLAY;
+
+		plane = drmm_universal_plane_alloc(drm, struct sprd_plane, base,
+						   1, &sprd_plane_funcs,
+						   layer_fmts, ARRAY_SIZE(layer_fmts),
+						   NULL, plane_type, NULL);
+		if (IS_ERR(plane)) {
+			drm_err(drm, "failed to init drm plane: %d\n", i);
+			return plane;
+		}
+
+		drm_plane_helper_add(&plane->base, &sprd_plane_helper_funcs);
+
+		sprd_plane_create_properties(plane, i);
+
+		if (i == 0)
+			primary = plane;
+	}
+
+	return primary;
+}
+
+static void sprd_crtc_mode_set_nofb(struct drm_crtc *crtc)
+{
+	struct sprd_dpu *dpu = to_sprd_crtc(crtc);
+	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
+
+	drm_display_mode_to_videomode(mode, &dpu->ctx.vm);
+
+	sprd_dpi_init(dpu);
+}
+
+static void sprd_crtc_atomic_enable(struct drm_crtc *crtc,
+				    struct drm_atomic_state *state)
+{
+	struct sprd_dpu *dpu = to_sprd_crtc(crtc);
+
+	sprd_dpu_init(dpu);
+
+	drm_crtc_vblank_on(&dpu->base);
+}
+
+static void sprd_crtc_atomic_disable(struct drm_crtc *crtc,
+				     struct drm_atomic_state *state)
+{
+	struct sprd_dpu *dpu = to_sprd_crtc(crtc);
+	struct drm_device *drm = dpu->base.dev;
+
+	drm_crtc_vblank_off(&dpu->base);
+
+	sprd_dpu_fini(dpu);
+
+	spin_lock_irq(&drm->event_lock);
+	if (crtc->state->event) {
+		drm_crtc_send_vblank_event(crtc, crtc->state->event);
+		crtc->state->event = NULL;
+	}
+	spin_unlock_irq(&drm->event_lock);
+}
+
+static void sprd_crtc_atomic_flush(struct drm_crtc *crtc,
+				   struct drm_atomic_state *state)
+
+{
+	struct sprd_dpu *dpu = to_sprd_crtc(crtc);
+	struct drm_device *drm = dpu->base.dev;
+
+	sprd_dpu_flip(dpu);
+
+	spin_lock_irq(&drm->event_lock);
+	if (crtc->state->event) {
+		drm_crtc_send_vblank_event(crtc, crtc->state->event);
+		crtc->state->event = NULL;
+	}
+	spin_unlock_irq(&drm->event_lock);
+}
+
+static int sprd_crtc_enable_vblank(struct drm_crtc *crtc)
+{
+	struct sprd_dpu *dpu = to_sprd_crtc(crtc);
+
+	dpu_reg_set(&dpu->ctx, REG_DPU_INT_EN, BIT_DPU_INT_VSYNC);
+
+	return 0;
+}
+
+static void sprd_crtc_disable_vblank(struct drm_crtc *crtc)
+{
+	struct sprd_dpu *dpu = to_sprd_crtc(crtc);
+
+	dpu_reg_clr(&dpu->ctx, REG_DPU_INT_EN, BIT_DPU_INT_VSYNC);
+}
+
+static const struct drm_crtc_helper_funcs sprd_crtc_helper_funcs = {
+	.mode_set_nofb	= sprd_crtc_mode_set_nofb,
+	.atomic_flush	= sprd_crtc_atomic_flush,
+	.atomic_enable	= sprd_crtc_atomic_enable,
+	.atomic_disable	= sprd_crtc_atomic_disable,
+};
+
+static const struct drm_crtc_funcs sprd_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	= sprd_crtc_enable_vblank,
+	.disable_vblank	= sprd_crtc_disable_vblank,
+};
+
+static struct sprd_dpu *sprd_crtc_init(struct drm_device *drm,
+				       struct drm_plane *primary, struct device *dev)
+{
+	struct device_node *port;
+	struct sprd_dpu *dpu;
+
+	dpu = drmm_crtc_alloc_with_planes(drm, struct sprd_dpu, base,
+					  primary, NULL,
+					&sprd_crtc_funcs, NULL);
+	if (IS_ERR(dpu)) {
+		drm_err(drm, "failed to init crtc\n");
+		return dpu;
+	}
+	drm_crtc_helper_add(&dpu->base, &sprd_crtc_helper_funcs);
+
+	/*
+	 * set crtc port so that drm_of_find_possible_crtcs call works
+	 */
+	port = of_graph_get_port_by_id(dev->of_node, 0);
+	if (!port) {
+		drm_err(drm, "failed to found crtc output port for %s\n",
+			dev->of_node->full_name);
+		return ERR_PTR(-EINVAL);
+	}
+	dpu->base.port = port;
+	of_node_put(port);
+
+	return dpu;
+}
+
+static irqreturn_t sprd_dpu_isr(int irq, void *data)
+{
+	struct sprd_dpu *dpu = data;
+	struct dpu_context *ctx = &dpu->ctx;
+	u32 reg_val, int_mask = 0;
+
+	reg_val = readl(ctx->base + REG_DPU_INT_STS);
+
+	/* disable err interrupt */
+	if (reg_val & BIT_DPU_INT_ERR) {
+		int_mask |= BIT_DPU_INT_ERR;
+		drm_warn(dpu->drm, "Warning: dpu underflow!\n");
+	}
+
+	/* dpu update done isr */
+	if (reg_val & BIT_DPU_INT_UPDATE_DONE) {
+		ctx->evt_update = true;
+		wake_up_interruptible_all(&ctx->wait_queue);
+	}
+
+	/* dpu stop done isr */
+	if (reg_val & BIT_DPU_INT_DONE) {
+		ctx->evt_stop = true;
+		wake_up_interruptible_all(&ctx->wait_queue);
+	}
+
+	if (reg_val & BIT_DPU_INT_VSYNC)
+		drm_crtc_handle_vblank(&dpu->base);
+
+	writel(reg_val, ctx->base + REG_DPU_INT_CLR);
+	dpu_reg_clr(ctx, REG_DPU_INT_EN, int_mask);
+
+	return IRQ_HANDLED;
+}
+
+static int sprd_dpu_context_init(struct sprd_dpu *dpu,
+				 struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct dpu_context *ctx = &dpu->ctx;
+	struct resource *res;
+	int ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ctx->base = devm_ioremap(dev, res->start, resource_size(res));
+	if (!ctx->base) {
+		dev_err(dev, "failed to map dpu registers\n");
+		return -EFAULT;
+	}
+
+	ctx->irq = platform_get_irq(pdev, 0);
+	if (ctx->irq < 0) {
+		dev_err(dev, "failed to get dpu irq\n");
+		return ctx->irq;
+	}
+
+	/* disable and clear interrupts before register dpu IRQ. */
+	writel(0x00, ctx->base + REG_DPU_INT_EN);
+	writel(0xff, ctx->base + REG_DPU_INT_CLR);
+
+	ret = devm_request_irq(dev, ctx->irq, sprd_dpu_isr,
+			       IRQF_TRIGGER_NONE, "DPU", dpu);
+	if (ret) {
+		dev_err(dev, "failed to register dpu irq handler\n");
+		return ret;
+	}
+
+	init_waitqueue_head(&ctx->wait_queue);
+
+	return 0;
+}
+
+static int sprd_dpu_bind(struct device *dev, struct device *master, void *data)
+{
+	struct drm_device *drm = data;
+	struct sprd_dpu *dpu;
+	struct sprd_plane *plane;
+	int ret;
+
+	plane = sprd_planes_init(drm);
+	if (IS_ERR(plane))
+		return PTR_ERR(plane);
+
+	dpu = sprd_crtc_init(drm, &plane->base, dev);
+	if (IS_ERR(dpu))
+		return PTR_ERR(dpu);
+
+	dpu->drm = drm;
+	dev_set_drvdata(dev, dpu);
+
+	ret = sprd_dpu_context_init(dpu, dev);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static const struct component_ops dpu_component_ops = {
+	.bind = sprd_dpu_bind,
+};
+
+static const struct of_device_id dpu_match_table[] = {
+	{ .compatible = "sprd,sharkl3-dpu" },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, dpu_match_table);
+
+static int sprd_dpu_probe(struct platform_device *pdev)
+{
+	return component_add(&pdev->dev, &dpu_component_ops);
+}
+
+static int sprd_dpu_remove(struct platform_device *pdev)
+{
+	component_del(&pdev->dev, &dpu_component_ops);
+
+	return 0;
+}
+
+struct platform_driver sprd_dpu_driver = {
+	.probe = sprd_dpu_probe,
+	.remove = sprd_dpu_remove,
+	.driver = {
+		.name = "sprd-dpu-drv",
+		.of_match_table = dpu_match_table,
+	},
+};
+
+MODULE_AUTHOR("Leon He <[e-mail]>");
+MODULE_AUTHOR("Kevin Tang <[e-mail]>");
+MODULE_DESCRIPTION("Unisoc Display Controller Driver");
+MODULE_LICENSE("GPL v2");

drivers/gpu/drm/sprd/sprd_dpu.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020 Unisoc Inc.
+ */
+
+#ifndef __SPRD_DPU_H__
+#define __SPRD_DPU_H__
+
+#include <linux/bug.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/string.h>
+#include <video/videomode.h>
+
+#include <drm/drm_crtc.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_print.h>
+#include <drm/drm_vblank.h>
+#include <uapi/drm/drm_mode.h>
+
+/* DPU Layer registers offset */
+#define DPU_LAY_REG_OFFSET	0x30
+
+enum {
+	SPRD_DPU_IF_DPI,
+	SPRD_DPU_IF_EDPI,
+	SPRD_DPU_IF_LIMIT
+};
+
+/**
+ * Sprd DPU context structure
+ *
+ * @base: DPU controller base address
+ * @irq: IRQ number to install the handler for
+ * @if_type: The type of DPI interface, default is DPI mode.
+ * @vm: videomode structure to use for DPU and DPI initialization
+ * @stopped: indicates whether DPU are stopped
+ * @wait_queue: wait queue, used to wait for DPU shadow register update done and
+ * DPU stop register done interrupt signal.
+ * @evt_update: wait queue condition for DPU shadow register
+ * @evt_stop: wait queue condition for DPU stop register
+ */
+struct dpu_context {
+	void __iomem *base;
+	int irq;
+	u8 if_type;
+	struct videomode vm;
+	bool stopped;
+	wait_queue_head_t wait_queue;
+	bool evt_update;
+	bool evt_stop;
+};
+
+/**
+ * Sprd DPU device structure
+ *
+ * @crtc: crtc object
+ * @drm: A point to drm device
+ * @ctx: DPU's implementation specific context object
+ */
+struct sprd_dpu {
+	struct drm_crtc base;
+	struct drm_device *drm;
+	struct dpu_context ctx;
+};
+
+static inline struct sprd_dpu *to_sprd_crtc(struct drm_crtc *crtc)
+{
+	return container_of(crtc, struct sprd_dpu, base);
+}
+
+static inline void
+dpu_reg_set(struct dpu_context *ctx, u32 offset, u32 set_bits)
+{
+	u32 bits = readl_relaxed(ctx->base + offset);
+
+	writel(bits | set_bits, ctx->base + offset);
+}
+
+static inline void
+dpu_reg_clr(struct dpu_context *ctx, u32 offset, u32 clr_bits)
+{
+	u32 bits = readl_relaxed(ctx->base + offset);
+
+	writel(bits & ~clr_bits, ctx->base + offset);
+}
+
+static inline u32
+layer_reg_rd(struct dpu_context *ctx, u32 offset, int index)
+{
+	u32 layer_offset = offset + index * DPU_LAY_REG_OFFSET;
+
+	return readl(ctx->base + layer_offset);
+}
+
+static inline void
+layer_reg_wr(struct dpu_context *ctx, u32 offset, u32 cfg_bits, int index)
+{
+	u32 layer_offset =  offset + index * DPU_LAY_REG_OFFSET;
+
+	writel(cfg_bits, ctx->base + layer_offset);
+}
+
+void sprd_dpu_run(struct sprd_dpu *dpu);
+void sprd_dpu_stop(struct sprd_dpu *dpu);
+
+#endif

drivers/gpu/drm/sprd/sprd_drm.c

···
 
 static struct platform_driver *sprd_drm_drivers[]  = {
 	&sprd_drm_driver,
+	&sprd_dpu_driver,
 };
 
 static int __init sprd_drm_init(void)

drivers/gpu/drm/sprd/sprd_drm.h

···
 	struct drm_device drm;
 };
 
+extern struct platform_driver sprd_dpu_driver;
+
 #endif /* _SPRD_DRM_H_ */