[PATCH 4/9] drm/mcde: replace struct drm_simple_display_pipe with regular atomic helpers

Ze Huang ze.huang at oss.qualcomm.com
Sat Jul 4 11:31:13 PDT 2026


Convert MCDE to explicit plane, CRTC and encoder objects.

Keep FIFO, event and framebuffer update sequencing intact, and install
GEM framebuffer prepare callback explicitly.

Signed-off-by: Ze Huang <ze.huang at oss.qualcomm.com>
---
 drivers/gpu/drm/mcde/mcde_display.c | 162 +++++++++++++++++++++++++++---------
 drivers/gpu/drm/mcde/mcde_drm.h     |   6 +-
 drivers/gpu/drm/mcde/mcde_drv.c     |   3 +-
 3 files changed, 129 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/mcde/mcde_display.c b/drivers/gpu/drm/mcde/mcde_display.c
index 257a6e84dd58..4d86fa5030eb 100644
--- a/drivers/gpu/drm/mcde/mcde_display.c
+++ b/drivers/gpu/drm/mcde/mcde_display.c
@@ -10,6 +10,7 @@
 #include <linux/regulator/consumer.h>
 #include <linux/media-bus-format.h>
 
+#include <drm/drm_atomic_helper.h>
 #include <drm/drm_device.h>
 #include <drm/drm_fb_dma_helper.h>
 #include <drm/drm_fourcc.h>
@@ -18,7 +19,6 @@
 #include <drm/drm_gem_dma_helper.h>
 #include <drm/drm_mipi_dsi.h>
 #include <drm/drm_print.h>
-#include <drm/drm_simple_kms_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_vblank.h>
 #include <video/mipi_display.h>
@@ -132,7 +132,7 @@ void mcde_display_irq(struct mcde *mcde)
 	writel(mispp, mcde->regs + MCDE_RISPP);
 
 	if (vblank)
-		drm_crtc_handle_vblank(&mcde->pipe.crtc);
+		drm_crtc_handle_vblank(&mcde->crtc);
 
 	if (misovl)
 		dev_info(mcde->dev, "some stray overlay IRQ %08x\n", misovl);
@@ -157,13 +157,35 @@ void mcde_display_disable_irqs(struct mcde *mcde)
 	writel(0xFFFFFFFF, mcde->regs + MCDE_RISCHNL);
 }
 
-static int mcde_display_check(struct drm_simple_display_pipe *pipe,
-			      struct drm_plane_state *pstate,
-			      struct drm_crtc_state *cstate)
+static int mcde_plane_helper_atomic_check(struct drm_plane *plane,
+					  struct drm_atomic_commit *state)
 {
-	const struct drm_display_mode *mode = &cstate->mode;
-	struct drm_framebuffer *old_fb = pipe->plane.state->fb;
+	struct drm_plane_state *pstate = drm_atomic_get_new_plane_state(state, plane);
+	struct drm_crtc *crtc = pstate->crtc;
+	struct drm_crtc_state *cstate;
+	const struct drm_display_mode *mode;
+	struct drm_framebuffer *old_fb = plane->state->fb;
 	struct drm_framebuffer *fb = pstate->fb;
+	int ret;
+
+	if (!crtc)
+		return 0;
+
+	cstate = drm_atomic_get_new_crtc_state(state, crtc);
+	if (!cstate)
+		return 0;
+
+	ret = drm_atomic_helper_check_plane_state(pstate, cstate,
+						  DRM_PLANE_NO_SCALING,
+						  DRM_PLANE_NO_SCALING,
+						  false, false);
+	if (ret)
+		return ret;
+
+	if (!pstate->visible)
+		return 0;
+
+	mode = &cstate->mode;
 
 	if (fb) {
 		u32 offset = drm_fb_dma_get_gem_addr(fb, pstate, 0);
@@ -1149,16 +1171,14 @@ static void mcde_setup_dsi(struct mcde *mcde, const struct drm_display_mode *mod
 	*dsi_formatter_frame = formatter_frame;
 }
 
-static void mcde_display_enable(struct drm_simple_display_pipe *pipe,
-				struct drm_crtc_state *cstate,
-				struct drm_plane_state *plane_state)
+static void mcde_crtc_helper_atomic_enable(struct drm_crtc *crtc,
+					   struct drm_atomic_commit *state)
 {
-	struct drm_crtc *crtc = &pipe->crtc;
-	struct drm_plane *plane = &pipe->plane;
 	struct drm_device *drm = crtc->dev;
 	struct mcde *mcde = to_mcde(drm);
+	struct drm_crtc_state *cstate = crtc->state;
 	const struct drm_display_mode *mode = &cstate->mode;
-	struct drm_framebuffer *fb = plane->state->fb;
+	struct drm_framebuffer *fb = mcde->plane.state->fb;
 	u32 format = fb->format->format;
 	int dsi_pkt_size;
 	int fifo_wtrmrk;
@@ -1298,9 +1318,9 @@ static void mcde_display_enable(struct drm_simple_display_pipe *pipe,
 	dev_info(drm->dev, "MCDE display is enabled\n");
 }
 
-static void mcde_display_disable(struct drm_simple_display_pipe *pipe)
+static void mcde_crtc_helper_atomic_disable(struct drm_crtc *crtc,
+					    struct drm_atomic_commit *state)
 {
-	struct drm_crtc *crtc = &pipe->crtc;
 	struct drm_device *drm = crtc->dev;
 	struct mcde *mcde = to_mcde(drm);
 	struct drm_pending_vblank_event *event;
@@ -1381,17 +1401,23 @@ static void mcde_set_extsrc(struct mcde *mcde, u32 buffer_address)
 	writel(buffer_address + mcde->stride, mcde->regs + MCDE_EXTSRCXA1);
 }
 
-static void mcde_display_update(struct drm_simple_display_pipe *pipe,
-				struct drm_plane_state *old_pstate)
+static void mcde_plane_helper_atomic_update(struct drm_plane *plane,
+					    struct drm_atomic_commit *state)
 {
-	struct drm_crtc *crtc = &pipe->crtc;
-	struct drm_device *drm = crtc->dev;
-	struct mcde *mcde = to_mcde(drm);
-	struct drm_pending_vblank_event *event = crtc->state->event;
-	struct drm_plane *plane = &pipe->plane;
+	struct drm_crtc *crtc = plane->state->crtc;
+	struct drm_device *drm;
+	struct mcde *mcde;
+	struct drm_pending_vblank_event *event;
 	struct drm_plane_state *pstate = plane->state;
 	struct drm_framebuffer *fb = pstate->fb;
 
+	if (!crtc)
+		return;
+
+	drm = crtc->dev;
+	mcde = to_mcde(drm);
+	event = crtc->state->event;
+
 	/*
 	 * Handle any pending event first, we need to arm the vblank
 	 * interrupt before sending any update to the display so we don't
@@ -1443,9 +1469,8 @@ static void mcde_display_update(struct drm_simple_display_pipe *pipe,
 	}
 }
 
-static int mcde_display_enable_vblank(struct drm_simple_display_pipe *pipe)
+static int mcde_crtc_enable_vblank(struct drm_crtc *crtc)
 {
-	struct drm_crtc *crtc = &pipe->crtc;
 	struct drm_device *drm = crtc->dev;
 	struct mcde *mcde = to_mcde(drm);
 	u32 val;
@@ -1462,9 +1487,8 @@ static int mcde_display_enable_vblank(struct drm_simple_display_pipe *pipe)
 	return 0;
 }
 
-static void mcde_display_disable_vblank(struct drm_simple_display_pipe *pipe)
+static void mcde_crtc_disable_vblank(struct drm_crtc *crtc)
 {
-	struct drm_crtc *crtc = &pipe->crtc;
 	struct drm_device *drm = crtc->dev;
 	struct mcde *mcde = to_mcde(drm);
 
@@ -1474,13 +1498,56 @@ static void mcde_display_disable_vblank(struct drm_simple_display_pipe *pipe)
 	writel(0xFFFFFFFF, mcde->regs + MCDE_RISPP);
 }
 
-static struct drm_simple_display_pipe_funcs mcde_display_funcs = {
-	.check = mcde_display_check,
-	.enable = mcde_display_enable,
-	.disable = mcde_display_disable,
-	.update = mcde_display_update,
-	.enable_vblank = mcde_display_enable_vblank,
-	.disable_vblank = mcde_display_disable_vblank,
+static int mcde_crtc_helper_atomic_check(struct drm_crtc *crtc, struct drm_atomic_commit *state)
+{
+	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
+	int ret;
+
+	if (!crtc_state->enable)
+		goto out;
+
+	ret = drm_atomic_helper_check_crtc_primary_plane(crtc_state);
+	if (ret)
+		return ret;
+
+out:
+	return drm_atomic_add_affected_planes(state, crtc);
+}
+
+static const struct drm_crtc_funcs mcde_crtc_funcs = {
+	.reset			= drm_atomic_helper_crtc_reset,
+	.destroy		= drm_crtc_cleanup,
+	.set_config		= drm_atomic_helper_set_config,
+	.page_flip		= drm_atomic_helper_page_flip,
+	.atomic_duplicate_state	= drm_atomic_helper_crtc_duplicate_state,
+	.atomic_destroy_state	= drm_atomic_helper_crtc_destroy_state,
+	.enable_vblank		= mcde_crtc_enable_vblank,
+	.disable_vblank		= mcde_crtc_disable_vblank,
+};
+
+static const struct drm_crtc_helper_funcs mcde_crtc_helper_funcs = {
+	.atomic_check	= mcde_crtc_helper_atomic_check,
+	.atomic_enable	= mcde_crtc_helper_atomic_enable,
+	.atomic_disable	= mcde_crtc_helper_atomic_disable,
+};
+
+static const struct drm_plane_funcs mcde_plane_funcs = {
+	.update_plane		= drm_atomic_helper_update_plane,
+	.disable_plane		= drm_atomic_helper_disable_plane,
+	.reset			= drm_atomic_helper_plane_reset,
+	.destroy		= drm_plane_cleanup,
+	.atomic_duplicate_state	= drm_atomic_helper_plane_duplicate_state,
+	.atomic_destroy_state	= drm_atomic_helper_plane_destroy_state,
+};
+
+static const struct drm_plane_helper_funcs mcde_plane_helper_funcs = {
+	.prepare_fb	= drm_gem_plane_helper_prepare_fb,
+	.atomic_check	= mcde_plane_helper_atomic_check,
+	.atomic_update	= mcde_plane_helper_atomic_update,
+};
+
+static const struct drm_encoder_funcs mcde_encoder_funcs = {
+	.destroy = drm_encoder_cleanup,
 };
 
 int mcde_display_init(struct drm_device *drm)
@@ -1510,11 +1577,30 @@ int mcde_display_init(struct drm_device *drm)
 	if (ret)
 		return ret;
 
-	ret = drm_simple_display_pipe_init(drm, &mcde->pipe,
-					   &mcde_display_funcs,
-					   formats, ARRAY_SIZE(formats),
-					   NULL,
-					   mcde->connector);
+	ret = drm_universal_plane_init(drm, &mcde->plane, 0,
+				       &mcde_plane_funcs,
+				       formats, ARRAY_SIZE(formats),
+				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
+	if (ret)
+		return ret;
+
+	drm_plane_helper_add(&mcde->plane, &mcde_plane_helper_funcs);
+
+	ret = drm_crtc_init_with_planes(drm, &mcde->crtc, &mcde->plane,
+					NULL, &mcde_crtc_funcs, NULL);
+	if (ret)
+		return ret;
+
+	drm_crtc_helper_add(&mcde->crtc, &mcde_crtc_helper_funcs);
+
+	ret = drm_encoder_init(drm, &mcde->encoder, &mcde_encoder_funcs,
+			       DRM_MODE_ENCODER_NONE, NULL);
+	if (ret)
+		return ret;
+
+	mcde->encoder.possible_crtcs = drm_crtc_mask(&mcde->crtc);
+
+	ret = drm_connector_attach_encoder(mcde->connector, &mcde->encoder);
 	if (ret)
 		return ret;
 
diff --git a/drivers/gpu/drm/mcde/mcde_drm.h b/drivers/gpu/drm/mcde/mcde_drm.h
index ecb70b4b737c..6123afb1e3b8 100644
--- a/drivers/gpu/drm/mcde/mcde_drm.h
+++ b/drivers/gpu/drm/mcde/mcde_drm.h
@@ -4,7 +4,7 @@
  * Parts of this file were based on the MCDE driver by Marcus Lorentzon
  * (C) ST-Ericsson SA 2013
  */
-#include <drm/drm_simple_kms_helper.h>
+#include <drm/drm_encoder.h>
 
 #ifndef _MCDE_DRM_H_
 #define _MCDE_DRM_H_
@@ -72,7 +72,9 @@ struct mcde {
 	struct drm_panel *panel;
 	struct drm_bridge *bridge;
 	struct drm_connector *connector;
-	struct drm_simple_display_pipe pipe;
+	struct drm_plane plane;
+	struct drm_crtc crtc;
+	struct drm_encoder encoder;
 	struct mipi_dsi_device *mdsi;
 	bool dpi_output;
 	s16 stride;
diff --git a/drivers/gpu/drm/mcde/mcde_drv.c b/drivers/gpu/drm/mcde/mcde_drv.c
index 5f2c462bad7e..401cf8ab83bc 100644
--- a/drivers/gpu/drm/mcde/mcde_drv.c
+++ b/drivers/gpu/drm/mcde/mcde_drv.c
@@ -186,8 +186,7 @@ static int mcde_modeset_init(struct drm_device *drm)
 	}
 
 	/* Attach the bridge. */
-	ret = drm_simple_display_pipe_attach_bridge(&mcde->pipe,
-						    mcde->bridge);
+	ret = drm_bridge_attach(&mcde->encoder, mcde->bridge, NULL, 0);
 	if (ret) {
 		dev_err(drm->dev, "failed to attach display output bridge\n");
 		return ret;

-- 
2.55.0




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