[PATCH 1/9] drm/arcpgu: replace struct drm_simple_display_pipe with regular atomic helpers

Ze Huang ze.huang at oss.qualcomm.com
Sat Jul 4 11:31:10 PDT 2026


Instantiate plane, CRTC and encoder directly and wire them up with
standard atomic helpers.

This removes arcpgu's dependency on deprecated simple-KMS display pipe
interface.

Signed-off-by: Ze Huang <ze.huang at oss.qualcomm.com>
---
 drivers/gpu/drm/tiny/arcpgu.c | 165 +++++++++++++++++++++++++++++++++---------
 1 file changed, 131 insertions(+), 34 deletions(-)

diff --git a/drivers/gpu/drm/tiny/arcpgu.c b/drivers/gpu/drm/tiny/arcpgu.c
index c93d61ac0bb7..375cdb79e4e8 100644
--- a/drivers/gpu/drm/tiny/arcpgu.c
+++ b/drivers/gpu/drm/tiny/arcpgu.c
@@ -17,12 +17,12 @@
 #include <drm/drm_fbdev_dma.h>
 #include <drm/drm_fourcc.h>
 #include <drm/drm_framebuffer.h>
+#include <drm/drm_gem_atomic_helper.h>
 #include <drm/drm_gem_dma_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_module.h>
 #include <drm/drm_of.h>
 #include <drm/drm_probe_helper.h>
-#include <drm/drm_simple_kms_helper.h>
 #include <linux/dma-mapping.h>
 #include <linux/module.h>
 #include <linux/of_reserved_mem.h>
@@ -52,14 +52,14 @@ struct arcpgu_drm_private {
 	struct drm_device	drm;
 	void __iomem		*regs;
 	struct clk		*clk;
-	struct drm_simple_display_pipe pipe;
+	struct drm_plane	plane;
+	struct drm_crtc		crtc;
+	struct drm_encoder	encoder;
 	struct drm_connector	sim_conn;
 };
 
 #define dev_to_arcpgu(x) container_of(x, struct arcpgu_drm_private, drm)
 
-#define pipe_to_arcpgu_priv(x) container_of(x, struct arcpgu_drm_private, pipe)
-
 static inline void arc_pgu_write(struct arcpgu_drm_private *arcpgu,
 				 unsigned int reg, u32 value)
 {
@@ -117,7 +117,7 @@ static const u32 arc_pgu_supported_formats[] = {
 
 static void arc_pgu_set_pxl_fmt(struct arcpgu_drm_private *arcpgu)
 {
-	const struct drm_framebuffer *fb = arcpgu->pipe.plane.state->fb;
+	const struct drm_framebuffer *fb = arcpgu->plane.state->fb;
 	uint32_t pixel_format = fb->format->format;
 	u32 format = DRM_FORMAT_INVALID;
 	int i;
@@ -139,10 +139,10 @@ static void arc_pgu_set_pxl_fmt(struct arcpgu_drm_private *arcpgu)
 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, reg_ctrl);
 }
 
-static enum drm_mode_status arc_pgu_mode_valid(struct drm_simple_display_pipe *pipe,
-					       const struct drm_display_mode *mode)
+static enum drm_mode_status arcpgu_crtc_helper_mode_valid(struct drm_crtc *crtc,
+							  const struct drm_display_mode *mode)
 {
-	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
+	struct arcpgu_drm_private *arcpgu = dev_to_arcpgu(crtc->dev);
 	long rate, clk_rate = mode->clock * 1000;
 	long diff = clk_rate / 200; /* +-0.5% allowed by HDMI spec */
 
@@ -155,7 +155,7 @@ static enum drm_mode_status arc_pgu_mode_valid(struct drm_simple_display_pipe *p
 
 static void arc_pgu_mode_set(struct arcpgu_drm_private *arcpgu)
 {
-	struct drm_display_mode *m = &arcpgu->pipe.crtc.state->adjusted_mode;
+	struct drm_display_mode *m = &arcpgu->crtc.state->adjusted_mode;
 	u32 val;
 
 	arc_pgu_write(arcpgu, ARCPGU_REG_FMT,
@@ -194,11 +194,10 @@ static void arc_pgu_mode_set(struct arcpgu_drm_private *arcpgu)
 	clk_set_rate(arcpgu->clk, m->crtc_clock * 1000);
 }
 
-static void arc_pgu_enable(struct drm_simple_display_pipe *pipe,
-			   struct drm_crtc_state *crtc_state,
-			   struct drm_plane_state *plane_state)
+static void arcpgu_crtc_helper_atomic_enable(struct drm_crtc *crtc,
+					     struct drm_atomic_commit *state)
 {
-	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
+	struct arcpgu_drm_private *arcpgu = dev_to_arcpgu(crtc->dev);
 
 	arc_pgu_mode_set(arcpgu);
 
@@ -208,9 +207,10 @@ static void arc_pgu_enable(struct drm_simple_display_pipe *pipe,
 		      ARCPGU_CTRL_ENABLE_MASK);
 }
 
-static void arc_pgu_disable(struct drm_simple_display_pipe *pipe)
+static void arcpgu_crtc_helper_atomic_disable(struct drm_crtc *crtc,
+					      struct drm_atomic_commit *state)
 {
-	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
+	struct arcpgu_drm_private *arcpgu = dev_to_arcpgu(crtc->dev);
 
 	clk_disable_unprepare(arcpgu->clk);
 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
@@ -218,35 +218,106 @@ static void arc_pgu_disable(struct drm_simple_display_pipe *pipe)
 			      ~ARCPGU_CTRL_ENABLE_MASK);
 }
 
-static void arc_pgu_update(struct drm_simple_display_pipe *pipe,
-			   struct drm_plane_state *state)
+static void arcpgu_plane_helper_atomic_update(struct drm_plane *plane,
+					      struct drm_atomic_commit *state)
 {
 	struct arcpgu_drm_private *arcpgu;
 	struct drm_gem_dma_object *gem;
 
-	if (!pipe->plane.state->fb)
+	if (!plane->state->fb)
 		return;
 
-	arcpgu = pipe_to_arcpgu_priv(pipe);
-	gem = drm_fb_dma_get_gem_obj(pipe->plane.state->fb, 0);
+	arcpgu = dev_to_arcpgu(plane->dev);
+	gem = drm_fb_dma_get_gem_obj(plane->state->fb, 0);
 	arc_pgu_write(arcpgu, ARCPGU_REG_BUF0_ADDR, gem->dma_addr);
 }
 
-static const struct drm_simple_display_pipe_funcs arc_pgu_pipe_funcs = {
-	.update = arc_pgu_update,
-	.mode_valid = arc_pgu_mode_valid,
-	.enable	= arc_pgu_enable,
-	.disable = arc_pgu_disable,
-};
-
 static const struct drm_mode_config_funcs arcpgu_drm_modecfg_funcs = {
-	.fb_create  = drm_gem_fb_create,
+	.fb_create = drm_gem_fb_create,
 	.atomic_check = drm_atomic_helper_check,
 	.atomic_commit = drm_atomic_helper_commit,
 };
 
 DEFINE_DRM_GEM_DMA_FOPS(arcpgu_drm_ops);
 
+static int arcpgu_plane_helper_atomic_check(struct drm_plane *plane,
+					    struct drm_atomic_commit *state)
+{
+	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
+	struct drm_crtc *crtc = plane_state->crtc;
+	struct drm_crtc_state *crtc_state = NULL;
+	int ret;
+
+	if (crtc)
+		crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
+
+	ret = drm_atomic_helper_check_plane_state(plane_state, crtc_state,
+						  DRM_PLANE_NO_SCALING,
+						  DRM_PLANE_NO_SCALING,
+						  false, false);
+	return ret;
+}
+
+static const struct drm_plane_helper_funcs arcpgu_plane_helper_funcs = {
+	.prepare_fb	= drm_gem_plane_helper_prepare_fb,
+	.atomic_check	= arcpgu_plane_helper_atomic_check,
+	.atomic_update	= arcpgu_plane_helper_atomic_update,
+};
+
+static bool arcpgu_plane_format_mod_supported(struct drm_plane *plane,
+					      u32 format,
+					      u64 modifier)
+{
+	return modifier == DRM_FORMAT_MOD_LINEAR;
+}
+
+static const struct drm_plane_funcs arcpgu_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,
+	.format_mod_supported	= arcpgu_plane_format_mod_supported,
+};
+
+static int arcpgu_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_helper_funcs arcpgu_crtc_helper_funcs = {
+	.mode_valid	= arcpgu_crtc_helper_mode_valid,
+	.atomic_check	= arcpgu_crtc_helper_atomic_check,
+	.atomic_enable	= arcpgu_crtc_helper_atomic_enable,
+	.atomic_disable	= arcpgu_crtc_helper_atomic_disable,
+};
+
+static const struct drm_crtc_funcs arcpgu_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,
+};
+
+static const struct drm_encoder_funcs arcpgu_encoder_funcs = {
+	.destroy = drm_encoder_cleanup,
+};
+
 static int arcpgu_load(struct arcpgu_drm_private *arcpgu)
 {
 	struct platform_device *pdev = to_platform_device(arcpgu->drm.dev);
@@ -254,6 +325,9 @@ static int arcpgu_load(struct arcpgu_drm_private *arcpgu)
 	struct device_node *endpoint_node = NULL;
 	struct drm_connector *connector = NULL;
 	struct drm_device *drm = &arcpgu->drm;
+	struct drm_plane *plane;
+	struct drm_encoder *encoder;
+	struct drm_crtc *crtc;
 	int ret;
 
 	arcpgu->clk = devm_clk_get(drm->dev, "pxlclk");
@@ -301,12 +375,35 @@ static int arcpgu_load(struct arcpgu_drm_private *arcpgu)
 			return ret;
 	}
 
-	ret = drm_simple_display_pipe_init(drm, &arcpgu->pipe, &arc_pgu_pipe_funcs,
-					   arc_pgu_supported_formats,
-					   ARRAY_SIZE(arc_pgu_supported_formats),
-					   NULL, connector);
+	plane = &arcpgu->plane;
+	ret = drm_universal_plane_init(drm, plane, 0,
+				       &arcpgu_plane_funcs,
+				       arc_pgu_supported_formats,
+				       ARRAY_SIZE(arc_pgu_supported_formats),
+				       NULL,
+				       DRM_PLANE_TYPE_PRIMARY, NULL);
 	if (ret)
 		return ret;
+	drm_plane_helper_add(plane, &arcpgu_plane_helper_funcs);
+
+	crtc = &arcpgu->crtc;
+	ret = drm_crtc_init_with_planes(drm, crtc, plane, NULL,
+					&arcpgu_crtc_funcs, NULL);
+	if (ret)
+		return ret;
+	drm_crtc_helper_add(crtc, &arcpgu_crtc_helper_funcs);
+
+	encoder = &arcpgu->encoder;
+	ret = drm_encoder_init(drm, encoder, &arcpgu_encoder_funcs, DRM_MODE_ENCODER_NONE, NULL);
+	if (ret)
+		return ret;
+	encoder->possible_crtcs = drm_crtc_mask(crtc);
+
+	if (connector) {
+		ret = drm_connector_attach_encoder(connector, encoder);
+		if (ret)
+			return ret;
+	}
 
 	if (encoder_node) {
 		/* Locate drm bridge from the hdmi encoder DT node */
@@ -315,7 +412,7 @@ static int arcpgu_load(struct arcpgu_drm_private *arcpgu)
 		if (!bridge)
 			return -EPROBE_DEFER;
 
-		ret = drm_simple_display_pipe_attach_bridge(&arcpgu->pipe, bridge);
+		ret = drm_bridge_attach(encoder, bridge, NULL, 0);
 		if (ret)
 			return ret;
 	}
@@ -342,7 +439,7 @@ static int arcpgu_show_pxlclock(struct seq_file *m, void *arg)
 	struct drm_device *drm = node->minor->dev;
 	struct arcpgu_drm_private *arcpgu = dev_to_arcpgu(drm);
 	unsigned long clkrate = clk_get_rate(arcpgu->clk);
-	unsigned long mode_clock = arcpgu->pipe.crtc.mode.crtc_clock * 1000;
+	unsigned long mode_clock = arcpgu->crtc.mode.crtc_clock * 1000;
 
 	seq_printf(m, "hw  : %lu\n", clkrate);
 	seq_printf(m, "mode: %lu\n", mode_clock);

-- 
2.55.0




More information about the linux-arm-kernel mailing list