[PATCH 0/5] drm/exynos: rework vblank handling - fixes

[PATCH 0/5] drm/exynos: rework vblank handling - fixes

[Andrzej Hajda]

Hi Inki,

According to you request, this is actual resend of my patchset v3
'drm/exynos: rework vblank handling' split into fixes and enhancements part.

This 'fixes' part is based on today's exynos-drm-fixes branch, original
patches applied without conflict.

The last patch does not really fit into vblank category,
but for sure it is a fix.

Regards
Andrzej


Andrzej Hajda (5):
  drm/exynos: move crtc event handling to drivers callbacks
  drm/exynos/decon5433: fix vblank event handling
  drm/exynos/decon5433: signal frame done interrupt at front porch
  drm/exynos/fimd: signal frame done interrupt at front porch
  drm/exynos/decon5433: fix software trigger mask

 drivers/gpu/drm/exynos/exynos5433_drm_decon.c | 85 +++++++++++++++++++++++++--
 drivers/gpu/drm/exynos/exynos7_drm_decon.c    |  1 +
 drivers/gpu/drm/exynos/exynos_drm_crtc.c      | 29 +++++----
 drivers/gpu/drm/exynos/exynos_drm_crtc.h      |  2 +
 drivers/gpu/drm/exynos/exynos_drm_fimd.c      |  4 +-
 drivers/gpu/drm/exynos/exynos_drm_vidi.c      |  1 +
 drivers/gpu/drm/exynos/exynos_mixer.c         |  1 +
 include/video/exynos5433_decon.h              | 12 ++++
 8 files changed, 117 insertions(+), 18 deletions(-)

-- 
2.7.4

[PATCH 1/5] drm/exynos: move crtc event handling to drivers callbacks

[Andrzej Hajda]

CRTC event is currently send with next vblank, or instantly in case crtc
is being disabled. This approach usually works, but in corner cases it can
result in premature event generation. Only device driver is able to verify
if the event can be sent. This patch is a first step in that direction - it
moves event handling to the drivers.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
 drivers/gpu/drm/exynos/exynos5433_drm_decon.c |  1 +
 drivers/gpu/drm/exynos/exynos7_drm_decon.c    |  1 +
 drivers/gpu/drm/exynos/exynos_drm_crtc.c      | 29 +++++++++++++++------------
 drivers/gpu/drm/exynos/exynos_drm_crtc.h      |  2 ++
 drivers/gpu/drm/exynos/exynos_drm_fimd.c      |  2 ++
 drivers/gpu/drm/exynos/exynos_drm_vidi.c      |  1 +
 drivers/gpu/drm/exynos/exynos_mixer.c         |  1 +
 7 files changed, 24 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
index cca32a4..2130ccf 100644
--- a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
+++ b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
@@ -378,6 +378,7 @@ static void decon_atomic_flush(struct exynos_drm_crtc *crtc)
 
 	if (ctx->out_type & IFTYPE_I80)
 		set_bit(BIT_WIN_UPDATED, &ctx->flags);
+	exynos_crtc_handle_event(crtc);
 }
 
 static void decon_swreset(struct decon_context *ctx)
diff --git a/drivers/gpu/drm/exynos/exynos7_drm_decon.c b/drivers/gpu/drm/exynos/exynos7_drm_decon.c
index f9ab19e..4881180 100644
--- a/drivers/gpu/drm/exynos/exynos7_drm_decon.c
+++ b/drivers/gpu/drm/exynos/exynos7_drm_decon.c
@@ -526,6 +526,7 @@ static void decon_atomic_flush(struct exynos_drm_crtc *crtc)
 
 	for (i = 0; i < WINDOWS_NR; i++)
 		decon_shadow_protect_win(ctx, i, false);
+	exynos_crtc_handle_event(crtc);
 }
 
 static void decon_init(struct decon_context *ctx)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
index 5367b66..c65f450 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_crtc.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
@@ -85,16 +85,28 @@ static void exynos_crtc_atomic_flush(struct drm_crtc *crtc,
 				     struct drm_crtc_state *old_crtc_state)
 {
 	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
-	struct drm_pending_vblank_event *event;
-	unsigned long flags;
 
 	if (exynos_crtc->ops->atomic_flush)
 		exynos_crtc->ops->atomic_flush(exynos_crtc);
+}
+
+static const struct drm_crtc_helper_funcs exynos_crtc_helper_funcs = {
+	.enable		= exynos_drm_crtc_enable,
+	.disable	= exynos_drm_crtc_disable,
+	.mode_set_nofb	= exynos_drm_crtc_mode_set_nofb,
+	.atomic_check	= exynos_crtc_atomic_check,
+	.atomic_begin	= exynos_crtc_atomic_begin,
+	.atomic_flush	= exynos_crtc_atomic_flush,
+};
+
+void exynos_crtc_handle_event(struct exynos_drm_crtc *exynos_crtc)
+{
+	struct drm_crtc *crtc = &exynos_crtc->base;
+	struct drm_pending_vblank_event *event = crtc->state->event;
+	unsigned long flags;
 
-	event = crtc->state->event;
 	if (event) {
 		crtc->state->event = NULL;
-
 		spin_lock_irqsave(&crtc->dev->event_lock, flags);
 		if (drm_crtc_vblank_get(crtc) == 0)
 			drm_crtc_arm_vblank_event(crtc, event);
@@ -105,15 +117,6 @@ static void exynos_crtc_atomic_flush(struct drm_crtc *crtc,
 
 }
 
-static const struct drm_crtc_helper_funcs exynos_crtc_helper_funcs = {
-	.enable		= exynos_drm_crtc_enable,
-	.disable	= exynos_drm_crtc_disable,
-	.mode_set_nofb	= exynos_drm_crtc_mode_set_nofb,
-	.atomic_check	= exynos_crtc_atomic_check,
-	.atomic_begin	= exynos_crtc_atomic_begin,
-	.atomic_flush	= exynos_crtc_atomic_flush,
-};
-
 static void exynos_drm_crtc_destroy(struct drm_crtc *crtc)
 {
 	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.h b/drivers/gpu/drm/exynos/exynos_drm_crtc.h
index 6a581a8..abd5d6c 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_crtc.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.h
@@ -40,4 +40,6 @@ int exynos_drm_crtc_get_pipe_from_type(struct drm_device *drm_dev,
  */
 void exynos_drm_crtc_te_handler(struct drm_crtc *crtc);
 
+void exynos_crtc_handle_event(struct exynos_drm_crtc *exynos_crtc);
+
 #endif
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
index 661b9fe..a3162a4 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
@@ -709,6 +709,8 @@ static void fimd_atomic_flush(struct exynos_drm_crtc *crtc)
 
 	for (i = 0; i < WINDOWS_NR; i++)
 		fimd_shadow_protect_win(ctx, i, false);
+
+	exynos_crtc_handle_event(crtc);
 }
 
 static void fimd_update_plane(struct exynos_drm_crtc *crtc,
diff --git a/drivers/gpu/drm/exynos/exynos_drm_vidi.c b/drivers/gpu/drm/exynos/exynos_drm_vidi.c
index 57fe514..5d9a62a 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_vidi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_vidi.c
@@ -170,6 +170,7 @@ static const struct exynos_drm_crtc_ops vidi_crtc_ops = {
 	.enable_vblank = vidi_enable_vblank,
 	.disable_vblank = vidi_disable_vblank,
 	.update_plane = vidi_update_plane,
+	.atomic_flush = exynos_crtc_handle_event,
 };
 
 static void vidi_fake_vblank_timer(unsigned long arg)
diff --git a/drivers/gpu/drm/exynos/exynos_mixer.c b/drivers/gpu/drm/exynos/exynos_mixer.c
index 72143ac..25edb63 100644
--- a/drivers/gpu/drm/exynos/exynos_mixer.c
+++ b/drivers/gpu/drm/exynos/exynos_mixer.c
@@ -1012,6 +1012,7 @@ static void mixer_atomic_flush(struct exynos_drm_crtc *crtc)
 		return;
 
 	mixer_vsync_set_update(mixer_ctx, true);
+	exynos_crtc_handle_event(crtc);
 }
 
 static void mixer_enable(struct exynos_drm_crtc *crtc)
-- 
2.7.4

[PATCH 2/5] drm/exynos/decon5433: fix vblank event handling

[Andrzej Hajda]

Current implementation of event handling assumes that vblank interrupt is
always called at the right time. It is not true, it can be delayed due to
various reasons. As a result different races can happen. The patch fixes
the issue by using hardware frame counter present in DECON to serialize
vblank and commit completion events.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
v3:
  - handle wrap-around of frame counter
v2:
  - added internal decon_get_frame_count function,
  - updated frame counter on flush,
  - misc style fixes (thank Inki)
---
 drivers/gpu/drm/exynos/exynos5433_drm_decon.c | 78 ++++++++++++++++++++++++++-
 include/video/exynos5433_decon.h              |  8 +++
 2 files changed, 85 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
index 2130ccf..cfe6f8a 100644
--- a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
+++ b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
@@ -68,6 +68,8 @@ struct decon_context {
 	unsigned long			flags;
 	unsigned long			out_type;
 	int				first_win;
+	spinlock_t			vblank_lock;
+	u32				frame_id;
 };
 
 static const uint32_t decon_formats[] = {
@@ -122,6 +124,48 @@ 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 = 2;
+
+	/* To get consistent result repeat read until frame id is stable.
+	 * Usually the loop will be executed once, in rare cases when the loop
+	 * is executed at frame change time 2nd pass will be needed.
+	 */
+	frm = readl(ctx->addr + DECON_CRFMID);
+	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;
+		break;
+	default:
+		break;
+	}
+
+	return frm;
+}
+
 static void decon_setup_trigger(struct decon_context *ctx)
 {
 	if (!(ctx->out_type & (IFTYPE_I80 | I80_HW_TRG)))
@@ -365,11 +409,14 @@ static void decon_disable_plane(struct exynos_drm_crtc *crtc,
 static void decon_atomic_flush(struct exynos_drm_crtc *crtc)
 {
 	struct decon_context *ctx = crtc->ctx;
+	unsigned long flags;
 	int i;
 
 	if (test_bit(BIT_SUSPENDED, &ctx->flags))
 		return;
 
+	spin_lock_irqsave(&ctx->vblank_lock, flags);
+
 	for (i = ctx->first_win; i < WINDOWS_NR; i++)
 		decon_shadow_protect_win(ctx, i, false);
 
@@ -378,12 +425,18 @@ static void decon_atomic_flush(struct exynos_drm_crtc *crtc)
 
 	if (ctx->out_type & IFTYPE_I80)
 		set_bit(BIT_WIN_UPDATED, &ctx->flags);
+
+	ctx->frame_id = decon_get_frame_count(ctx, true);
+
 	exynos_crtc_handle_event(crtc);
+
+	spin_unlock_irqrestore(&ctx->vblank_lock, flags);
 }
 
 static void decon_swreset(struct decon_context *ctx)
 {
 	unsigned int tries;
+	unsigned long flags;
 
 	writel(0, ctx->addr + DECON_VIDCON0);
 	for (tries = 2000; tries; --tries) {
@@ -401,6 +454,10 @@ static void decon_swreset(struct decon_context *ctx)
 
 	WARN(tries == 0, "failed to software reset DECON\n");
 
+	spin_lock_irqsave(&ctx->vblank_lock, flags);
+	ctx->frame_id = 0;
+	spin_unlock_irqrestore(&ctx->vblank_lock, flags);
+
 	if (!(ctx->out_type & IFTYPE_HDMI))
 		return;
 
@@ -579,6 +636,24 @@ static const struct component_ops decon_component_ops = {
 	.unbind = decon_unbind,
 };
 
+static void decon_handle_vblank(struct decon_context *ctx)
+{
+	u32 frm;
+
+	spin_lock(&ctx->vblank_lock);
+
+	frm = decon_get_frame_count(ctx, true);
+
+	if (frm != ctx->frame_id) {
+		/* handle only if incremented, take care of wrap-around */
+		if ((s32)(frm - ctx->frame_id) > 0)
+			drm_crtc_handle_vblank(&ctx->crtc->base);
+		ctx->frame_id = frm;
+	}
+
+	spin_unlock(&ctx->vblank_lock);
+}
+
 static irqreturn_t decon_irq_handler(int irq, void *dev_id)
 {
 	struct decon_context *ctx = dev_id;
@@ -599,7 +674,7 @@ static irqreturn_t decon_irq_handler(int irq, void *dev_id)
 			    (VIDOUT_INTERLACE_EN_F | VIDOUT_INTERLACE_FIELD_F))
 				return IRQ_HANDLED;
 		}
-		drm_crtc_handle_vblank(&ctx->crtc->base);
+		decon_handle_vblank(ctx);
 	}
 
 out:
@@ -672,6 +747,7 @@ static int exynos5433_decon_probe(struct platform_device *pdev)
 	__set_bit(BIT_SUSPENDED, &ctx->flags);
 	ctx->dev = dev;
 	ctx->out_type = (unsigned long)of_device_get_match_data(dev);
+	spin_lock_init(&ctx->vblank_lock);
 
 	if (ctx->out_type & IFTYPE_HDMI) {
 		ctx->first_win = 1;
diff --git a/include/video/exynos5433_decon.h b/include/video/exynos5433_decon.h
index ef8e2a8..352fc0d 100644
--- a/include/video/exynos5433_decon.h
+++ b/include/video/exynos5433_decon.h
@@ -46,6 +46,7 @@
 #define DECON_FRAMEFIFO_STATUS		0x0524
 #define DECON_CMU			0x1404
 #define DECON_UPDATE			0x1410
+#define DECON_CRFMID			0x1414
 #define DECON_UPDATE_SCHEME		0x1438
 #define DECON_VIDCON1			0x2000
 #define DECON_VIDCON2			0x2004
@@ -142,6 +143,13 @@
 #define STANDALONE_UPDATE_F		(1 << 0)
 
 /* DECON_VIDCON1 */
+#define VIDCON1_LINECNT_MASK		(0x0fff << 16)
+#define VIDCON1_I80_ACTIVE		(1 << 15)
+#define VIDCON1_VSTATUS_MASK		(0x3 << 13)
+#define VIDCON1_VSTATUS_VS		(0 << 13)
+#define VIDCON1_VSTATUS_BP		(1 << 13)
+#define VIDCON1_VSTATUS_AC		(2 << 13)
+#define VIDCON1_VSTATUS_FP		(3 << 13)
 #define VIDCON1_VCLK_MASK		(0x3 << 9)
 #define VIDCON1_VCLK_RUN_VDEN_DISABLE	(0x3 << 9)
 #define VIDCON1_VCLK_HOLD		(0x0 << 9)
-- 
2.7.4

[PATCH 3/5] drm/exynos/decon5433: signal frame done interrupt at front porch

[Andrzej Hajda]

DECON in case of video mode generates interrupt by default at start
of vertical back porch. As this interrupt is used to generate VBLANK
events more optimal point is start of vertical front porch.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
 drivers/gpu/drm/exynos/exynos5433_drm_decon.c | 2 +-
 include/video/exynos5433_decon.h              | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
index cfe6f8a..a43d0fa 100644
--- a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
+++ b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
@@ -105,7 +105,7 @@ static int decon_enable_vblank(struct exynos_drm_crtc *crtc)
 		if (ctx->out_type & IFTYPE_I80)
 			val |= VIDINTCON0_FRAMEDONE;
 		else
-			val |= VIDINTCON0_INTFRMEN;
+			val |= VIDINTCON0_INTFRMEN | VIDINTCON0_FRAMESEL_FP;
 
 		writel(val, ctx->addr + DECON_VIDINTCON0);
 	}
diff --git a/include/video/exynos5433_decon.h b/include/video/exynos5433_decon.h
index 352fc0d..6b083d3 100644
--- a/include/video/exynos5433_decon.h
+++ b/include/video/exynos5433_decon.h
@@ -127,6 +127,10 @@
 
 /* VIDINTCON0 */
 #define VIDINTCON0_FRAMEDONE		(1 << 17)
+#define VIDINTCON0_FRAMESEL_BP		(0 << 15)
+#define VIDINTCON0_FRAMESEL_VS		(1 << 15)
+#define VIDINTCON0_FRAMESEL_AC		(2 << 15)
+#define VIDINTCON0_FRAMESEL_FP		(3 << 15)
 #define VIDINTCON0_INTFRMEN		(1 << 12)
 #define VIDINTCON0_INTEN		(1 << 0)
 
-- 
2.7.4

[PATCH 4/5] drm/exynos/fimd: signal frame done interrupt at front porch

[Andrzej Hajda]

VBLANK interrupt should be signalled as soon as scanout ends, front porch
is the best moment.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_fimd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
index a3162a4..3f04d72 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
@@ -243,7 +243,7 @@ static int fimd_enable_vblank(struct exynos_drm_crtc *crtc)
 			val |= VIDINTCON0_INT_FRAME;
 
 			val &= ~VIDINTCON0_FRAMESEL0_MASK;
-			val |= VIDINTCON0_FRAMESEL0_VSYNC;
+			val |= VIDINTCON0_FRAMESEL0_FRONTPORCH;
 			val &= ~VIDINTCON0_FRAMESEL1_MASK;
 			val |= VIDINTCON0_FRAMESEL1_NONE;
 		}
-- 
2.7.4

[PATCH 5/5] drm/exynos/decon5433: fix software trigger mask

[Andrzej Hajda]

The patch fixes copy/paste bug introduced during code refactoring.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: b93c2e8b5d9d ("drm/exynos/decon5433: configure sysreg in case of hardware trigger")Fixes:
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
 drivers/gpu/drm/exynos/exynos5433_drm_decon.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
index a43d0fa..c0e8d33 100644
--- a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
+++ b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
@@ -172,8 +172,8 @@ static void decon_setup_trigger(struct decon_context *ctx)
 		return;
 
 	if (!(ctx->out_type & I80_HW_TRG)) {
-		writel(TRIGCON_TE_AUTO_MASK | TRIGCON_SWTRIGEN
-		       | TRIGCON_TE_AUTO_MASK | TRIGCON_SWTRIGEN,
+		writel(TRIGCON_TRIGEN_PER_F | TRIGCON_TRIGEN_F |
+		       TRIGCON_TE_AUTO_MASK | TRIGCON_SWTRIGEN,
 		       ctx->addr + DECON_TRIGCON);
 		return;
 	}
-- 
2.7.4

Re: [PATCH 0/5] drm/exynos: rework vblank handling - fixes

[Inki Dae]

Merged.

Thanks,
Inki Dae


2017년 03월 14일 17:27에 Andrzej Hajda 이(가) 쓴 글:
> Hi Inki,
> 
> According to you request, this is actual resend of my patchset v3
> 'drm/exynos: rework vblank handling' split into fixes and enhancements part.
> 
> This 'fixes' part is based on today's exynos-drm-fixes branch, original
> patches applied without conflict.
> 
> The last patch does not really fit into vblank category,
> but for sure it is a fix.
> 
> Regards
> Andrzej
> 
> 
> Andrzej Hajda (5):
>   drm/exynos: move crtc event handling to drivers callbacks
>   drm/exynos/decon5433: fix vblank event handling
>   drm/exynos/decon5433: signal frame done interrupt at front porch
>   drm/exynos/fimd: signal frame done interrupt at front porch
>   drm/exynos/decon5433: fix software trigger mask
> 
>  drivers/gpu/drm/exynos/exynos5433_drm_decon.c | 85 +++++++++++++++++++++++++--
>  drivers/gpu/drm/exynos/exynos7_drm_decon.c    |  1 +
>  drivers/gpu/drm/exynos/exynos_drm_crtc.c      | 29 +++++----
>  drivers/gpu/drm/exynos/exynos_drm_crtc.h      |  2 +
>  drivers/gpu/drm/exynos/exynos_drm_fimd.c      |  4 +-
>  drivers/gpu/drm/exynos/exynos_drm_vidi.c      |  1 +
>  drivers/gpu/drm/exynos/exynos_mixer.c         |  1 +
>  include/video/exynos5433_decon.h              | 12 ++++
>  8 files changed, 117 insertions(+), 18 deletions(-)
> 
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