[PATCH v4 3/6] drm: lcdif: Determine bus format and flags in ->atomic_check()

[Liu Ying]

Instead of determining LCDIF output bus format and bus flags in
->atomic_enable(), do that in ->atomic_check().  This is a
preparation for the upcoming patch to check consistent bus format
and bus flags across all first downstream bridges in ->atomic_check().
New lcdif_crtc_state structure is introduced to cache bus format
and bus flags states in ->atomic_check() so that they can be read
in ->atomic_enable().

Signed-off-by: Liu Ying <victor.liu@xxxxxxx>
---
v3->v4:
* Use 'new_{c,p}state' instead of 'new_{crtc,plane}_state'. (Alexander)
* Simplify lcdif_crtc_reset() by calling lcdif_crtc_atomic_destroy_state().
  (Alexander)
* Add '!crtc->state' check in lcdif_crtc_atomic_duplicate_state(). (Alexander)

v2->v3:
* No change.

v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)
* Add comment on the 'base' member of lcdif_crtc_state structure to
  note it should always be the first member. (Lothar)

 drivers/gpu/drm/mxsfb/lcdif_kms.c | 134 ++++++++++++++++++++++--------
 1 file changed, 99 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index e54200a9fcb9..d46de433cd8e 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -30,6 +30,18 @@
 #include "lcdif_drv.h"
 #include "lcdif_regs.h"
 
+struct lcdif_crtc_state {
+	struct drm_crtc_state	base;	/* always be the first member */
+	u32			bus_format;
+	u32			bus_flags;
+};
+
+static inline struct lcdif_crtc_state *
+to_lcdif_crtc_state(struct drm_crtc_state *s)
+{
+	return container_of(s, struct lcdif_crtc_state, base);
+}
+
 /* -----------------------------------------------------------------------------
  * CRTC
  */
@@ -385,48 +397,72 @@ static void lcdif_reset_block(struct lcdif_drm_private *lcdif)
 	readl(lcdif->base + LCDC_V8_CTRL);
 }
 
-static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
-				     struct drm_plane_state *plane_state,
-				     struct drm_bridge_state *bridge_state,
-				     const u32 bus_format)
+static void lcdif_crtc_mode_set_nofb(struct drm_crtc_state *crtc_state,
+				     struct drm_plane_state *plane_state)
 {
-	struct drm_device *drm = lcdif->crtc.dev;
-	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
-	u32 bus_flags = 0;
-
-	if (lcdif->bridge->timings)
-		bus_flags = lcdif->bridge->timings->input_bus_flags;
-	else if (bridge_state)
-		bus_flags = bridge_state->input_bus_cfg.flags;
+	struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
+	struct drm_device *drm = crtc_state->crtc->dev;
+	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
+	struct drm_display_mode *m = &crtc_state->adjusted_mode;
 
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Pixel clock: %dkHz (actual: %dkHz)\n",
 			     m->crtc_clock,
 			     (int)(clk_get_rate(lcdif->clk) / 1000));
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Bridge bus_flags: 0x%08X\n",
-			     bus_flags);
+			     lcdif_crtc_state->bus_flags);
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Mode flags: 0x%08X\n", m->flags);
 
 	/* Mandatory eLCDIF reset as per the Reference Manual */
 	lcdif_reset_block(lcdif);
 
-	lcdif_set_formats(lcdif, plane_state, bus_format);
+	lcdif_set_formats(lcdif, plane_state, lcdif_crtc_state->bus_format);
 
-	lcdif_set_mode(lcdif, bus_flags);
+	lcdif_set_mode(lcdif, lcdif_crtc_state->bus_flags);
 }
 
 static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
 				   struct drm_atomic_state *state)
 {
+	struct drm_device *drm = crtc->dev;
+	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
 									  crtc);
+	struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
 	bool has_primary = crtc_state->plane_mask &
 			   drm_plane_mask(crtc->primary);
+	struct drm_bridge_state *bridge_state;
+	struct drm_bridge *bridge = lcdif->bridge;
+	int ret;
 
 	/* The primary plane has to be enabled when the CRTC is active. */
 	if (crtc_state->active && !has_primary)
 		return -EINVAL;
 
-	return drm_atomic_add_affected_planes(state, crtc);
+	ret = drm_atomic_add_affected_planes(state, crtc);
+	if (ret)
+		return ret;
+
+	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
+	if (!bridge_state)
+		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_FIXED;
+	else
+		lcdif_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
+
+	if (lcdif_crtc_state->bus_format == MEDIA_BUS_FMT_FIXED) {
+		dev_warn_once(drm->dev,
+			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
+		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	}
+
+	if (bridge->timings)
+		lcdif_crtc_state->bus_flags = bridge->timings->input_bus_flags;
+	else if (bridge_state)
+		lcdif_crtc_state->bus_flags = bridge_state->input_bus_cfg.flags;
+	else
+		lcdif_crtc_state->bus_flags = 0;
+
+	return 0;
 }
 
 static void lcdif_crtc_atomic_flush(struct drm_crtc *crtc,
@@ -458,32 +494,18 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
 				     struct drm_atomic_state *state)
 {
 	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(crtc->dev);
+	struct drm_crtc_state *new_cstate = drm_atomic_get_new_crtc_state(state, crtc);
 	struct drm_plane_state *new_pstate = drm_atomic_get_new_plane_state(state,
 									    crtc->primary);
 	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
-	struct drm_bridge_state *bridge_state = NULL;
 	struct drm_device *drm = lcdif->drm;
-	u32 bus_format;
 	dma_addr_t paddr;
 
-	bridge_state = drm_atomic_get_new_bridge_state(state, lcdif->bridge);
-	if (!bridge_state)
-		bus_format = MEDIA_BUS_FMT_FIXED;
-	else
-		bus_format = bridge_state->input_bus_cfg.format;
-
-	if (bus_format == MEDIA_BUS_FMT_FIXED) {
-		dev_warn_once(drm->dev,
-			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
-			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
-		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
-	}
-
 	clk_set_rate(lcdif->clk, m->crtc_clock * 1000);
 
 	pm_runtime_get_sync(drm->dev);
 
-	lcdif_crtc_mode_set_nofb(lcdif, new_pstate, bridge_state, bus_format);
+	lcdif_crtc_mode_set_nofb(new_cstate, new_pstate);
 
 	/* Write cur_buf as well to avoid an initial corrupt frame */
 	paddr = drm_fb_dma_get_gem_addr(new_pstate->fb, new_pstate, 0);
@@ -520,6 +542,48 @@ static void lcdif_crtc_atomic_disable(struct drm_crtc *crtc,
 	pm_runtime_put_sync(drm->dev);
 }
 
+static void lcdif_crtc_atomic_destroy_state(struct drm_crtc *crtc,
+					    struct drm_crtc_state *state)
+{
+	__drm_atomic_helper_crtc_destroy_state(state);
+	kfree(to_lcdif_crtc_state(state));
+}
+
+static void lcdif_crtc_reset(struct drm_crtc *crtc)
+{
+	struct lcdif_crtc_state *state;
+
+	if (crtc->state)
+		lcdif_crtc_atomic_destroy_state(crtc, crtc->state);
+
+	crtc->state = NULL;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (state)
+		__drm_atomic_helper_crtc_reset(crtc, &state->base);
+}
+
+static struct drm_crtc_state *
+lcdif_crtc_atomic_duplicate_state(struct drm_crtc *crtc)
+{
+	struct lcdif_crtc_state *old = to_lcdif_crtc_state(crtc->state);
+	struct lcdif_crtc_state *new;
+
+	if (WARN_ON(!crtc->state))
+		return NULL;
+
+	new = kzalloc(sizeof(*new), GFP_KERNEL);
+	if (!new)
+		return NULL;
+
+	__drm_atomic_helper_crtc_duplicate_state(crtc, &new->base);
+
+	new->bus_format = old->bus_format;
+	new->bus_flags = old->bus_flags;
+
+	return &new->base;
+}
+
 static int lcdif_crtc_enable_vblank(struct drm_crtc *crtc)
 {
 	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(crtc->dev);
@@ -548,12 +612,12 @@ static const struct drm_crtc_helper_funcs lcdif_crtc_helper_funcs = {
 };
 
 static const struct drm_crtc_funcs lcdif_crtc_funcs = {
-	.reset = drm_atomic_helper_crtc_reset,
+	.reset = lcdif_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,
+	.atomic_duplicate_state = lcdif_crtc_atomic_duplicate_state,
+	.atomic_destroy_state = lcdif_crtc_atomic_destroy_state,
 	.enable_vblank = lcdif_crtc_enable_vblank,
 	.disable_vblank = lcdif_crtc_disable_vblank,
 };
-- 
2.37.1