[PATCH] drm/exynos/decon5433: implement frame counter

[Andrzej Hajda]

Decon in Exynos5433 has frame counter, it can be used to implement
get_vblank_counter callback.

Signed-off-by: Andrzej Hajda <a.hajda at samsung.com>
---
Hi Inki,

The patch is based on my last patches, maybe to make it clear I will resend all
these patches in one patchset, what do you think?

Regards
Andrzej

 drivers/gpu/drm/exynos/exynos5433_drm_decon.c | 76 ++++++++++++++++++---------
 drivers/gpu/drm/exynos/exynos_drm_crtc.c      | 11 ++++
 drivers/gpu/drm/exynos/exynos_drm_drv.h       |  1 +
 3 files changed, 63 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
index 4b596dc..4b5af67 100644
--- a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
+++ b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
@@ -123,6 +123,53 @@ static void decon_disable_vblank(struct exynos_drm_crtc *crtc)
 		writel(0, ctx->addr + DECON_VIDINTCON0);
 }
 
+/* return number of starts/ends of frame transmissions since reset */
+static u32 decon_get_frame_count(struct decon_context *ctx, bool end)
+{
+	u32 frm, pfrm, status, cnt;
+
+	/* To get consistent result repeat read until frame id is stable. */
+	frm = readl(ctx->addr + DECON_CRFMID);
+	cnt = 3;
+	do {
+		status = readl(ctx->addr + DECON_VIDCON1);
+		pfrm = frm;
+		frm = readl(ctx->addr + DECON_CRFMID);
+	} while (frm != pfrm && --cnt);
+
+	/* CRFMID is incremented on BPORCH in case of I80 and on VSYNC in case
+	 * of RGB, it should be taken into account.
+	 */
+	if (!frm)
+		return 0;
+
+	switch (status & (VIDCON1_VSTATUS_MASK | VIDCON1_I80_ACTIVE)) {
+	case VIDCON1_VSTATUS_VS:
+		if (!(ctx->out_type & IFTYPE_I80))
+			--frm;
+		break;
+	case VIDCON1_VSTATUS_BP:
+		--frm;
+		break;
+	case VIDCON1_I80_ACTIVE:
+	case VIDCON1_VSTATUS_AC:
+		if (end)
+			--frm;
+	}
+
+	return frm;
+}
+
+static u32 decon_get_vblank_counter(struct exynos_drm_crtc *crtc)
+{
+	struct decon_context *ctx = crtc->ctx;
+
+	if (test_bit(BIT_SUSPENDED, &ctx->flags))
+		return 0;
+
+	return decon_get_frame_count(ctx, false);
+}
+
 static void decon_setup_trigger(struct decon_context *ctx)
 {
 	if (!(ctx->out_type & (IFTYPE_I80 | I80_HW_TRG)))
@@ -518,6 +565,7 @@ static const struct exynos_drm_crtc_ops decon_crtc_ops = {
 	.enable			= decon_enable,
 	.disable		= decon_disable,
 	.enable_vblank		= decon_enable_vblank,
+	.get_vblank_counter	= decon_get_vblank_counter,
 	.disable_vblank		= decon_disable_vblank,
 	.atomic_begin		= decon_atomic_begin,
 	.update_plane		= decon_update_plane,
@@ -536,6 +584,7 @@ static int decon_bind(struct device *dev, struct device *master, void *data)
 	int ret;
 
 	ctx->drm_dev = drm_dev;
+	drm_dev->max_vblank_count = 0xffffffff;
 
 	for (win = ctx->first_win; win < WINDOWS_NR; win++) {
 		int tmp = (win == ctx->first_win) ? 0 : win;
@@ -581,34 +630,11 @@ static const struct component_ops decon_component_ops = {
 
 static void decon_handle_vblank(struct decon_context *ctx)
 {
-	u32 frm, pfrm, status, cnt;
+	u32 frm;
 
 	spin_lock(&ctx->vblank_lock);
 
-	/* To get consistent result repeat read until frame id is stable. */
-	frm = readl(ctx->addr + DECON_CRFMID);
-	cnt = 3;
-	do {
-		status = readl(ctx->addr + DECON_VIDCON1);
-		pfrm = frm;
-		frm = readl(ctx->addr + DECON_CRFMID);
-	} while (frm != pfrm && --cnt);
-
-	status &= VIDCON1_VSTATUS_MASK | VIDCON1_I80_ACTIVE;
-
-	/* In case of delayed vblank CRFMID could be already incremented,
-	 * it should be taken into account.
-	 */
-	if (frm > 0)
-		switch (status) {
-		case VIDCON1_VSTATUS_VS:
-			if (ctx->out_type & IFTYPE_I80)
-				break;
-		case VIDCON1_I80_ACTIVE:
-		case VIDCON1_VSTATUS_BP:
-		case VIDCON1_VSTATUS_AC:
-			--frm;
-		}
+	frm = decon_get_frame_count(ctx, true);
 
 	if (frm != ctx->frame_id) {
 		if (frm > ctx->frame_id)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
index 0c9a775..d72777f 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_crtc.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
@@ -132,6 +132,16 @@ static void exynos_drm_crtc_disable_vblank(struct drm_crtc *crtc)
 		exynos_crtc->ops->disable_vblank(exynos_crtc);
 }
 
+static u32 exynos_drm_crtc_get_vblank_counter(struct drm_crtc *crtc)
+{
+	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
+
+	if (exynos_crtc->ops->get_vblank_counter)
+		return exynos_crtc->ops->get_vblank_counter(exynos_crtc);
+
+	return 0;
+}
+
 static const struct drm_crtc_funcs exynos_crtc_funcs = {
 	.set_config	= drm_atomic_helper_set_config,
 	.page_flip	= drm_atomic_helper_page_flip,
@@ -141,6 +151,7 @@ static const struct drm_crtc_funcs exynos_crtc_funcs = {
 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
 	.enable_vblank = exynos_drm_crtc_enable_vblank,
 	.disable_vblank = exynos_drm_crtc_disable_vblank,
+	.get_vblank_counter = exynos_drm_crtc_get_vblank_counter,
 };
 
 struct exynos_drm_crtc *exynos_drm_crtc_create(struct drm_device *drm_dev,
diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.h b/drivers/gpu/drm/exynos/exynos_drm_drv.h
index e52f70a..527bf1d 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.h
@@ -131,6 +131,7 @@ struct exynos_drm_crtc_ops {
 	void (*disable)(struct exynos_drm_crtc *crtc);
 	int (*enable_vblank)(struct exynos_drm_crtc *crtc);
 	void (*disable_vblank)(struct exynos_drm_crtc *crtc);
+	u32 (*get_vblank_counter)(struct exynos_drm_crtc *crtc);
 	int (*atomic_check)(struct exynos_drm_crtc *crtc,
 			    struct drm_crtc_state *state);
 	void (*atomic_begin)(struct exynos_drm_crtc *crtc);
-- 
2.7.4