From a82d716ab4c2ab5f198f3461e32614defb52c724 Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.org>
Date: Thu, 25 Jul 2019 17:27:44 +0100
Subject: [PATCH] drm/vc4: Resolve the vblank warnings on mode
switching
The details over when and how a driver is to service the
vblank events are sketchy, and the fkms driver was triggering
a kernel warning every time the crtc was enabled or disabled.
Copy the event handling as used by the vc4-kms driver slightly
more closely, and we avoid the warnings.
https://github.com/raspberrypi/linux/issues/3020
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
---
drivers/gpu/drm/vc4/vc4_firmware_kms.c | 48 ++++++++++++++++++--------
1 file changed, 33 insertions(+), 15 deletions(-)
--- a/drivers/gpu/drm/vc4/vc4_firmware_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_firmware_kms.c
@@ -964,6 +964,7 @@ static void vc4_crtc_mode_set_nofb(struc
static void vc4_crtc_disable(struct drm_crtc *crtc, struct drm_crtc_state *old_state)
{
+ struct drm_device *dev = crtc->dev;
struct drm_plane *plane;
DRM_DEBUG_KMS("[CRTC:%d] vblanks off.\n",
@@ -979,6 +980,35 @@ static void vc4_crtc_disable(struct drm_
drm_atomic_crtc_for_each_plane(plane, crtc)
vc4_plane_atomic_disable(plane, plane->state);
+
+ /*
+ * Make sure we issue a vblank event after disabling the CRTC if
+ * someone was waiting it.
+ */
+ if (crtc->state->event) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+ drm_crtc_send_vblank_event(crtc, crtc->state->event);
+ crtc->state->event = NULL;
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+ }
+}
+
+static void vc4_crtc_consume_event(struct drm_crtc *crtc)
+{
+ struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+ struct drm_device *dev = crtc->dev;
+ unsigned long flags;
+
+ crtc->state->event->pipe = drm_crtc_index(crtc);
+
+ WARN_ON(drm_crtc_vblank_get(crtc) != 0);
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+ vc4_crtc->event = crtc->state->event;
+ crtc->state->event = NULL;
+ spin_unlock_irqrestore(&dev->event_lock, flags);
}
static void vc4_crtc_enable(struct drm_crtc *crtc, struct drm_crtc_state *old_state)
@@ -988,6 +1018,7 @@ static void vc4_crtc_enable(struct drm_c
DRM_DEBUG_KMS("[CRTC:%d] vblanks on.\n",
crtc->base.id);
drm_crtc_vblank_on(crtc);
+ vc4_crtc_consume_event(crtc);
/* Unblank the planes (if they're supposed to be displayed). */
drm_atomic_crtc_for_each_plane(plane, crtc)
@@ -1059,23 +1090,10 @@ static int vc4_crtc_atomic_check(struct
static void vc4_crtc_atomic_flush(struct drm_crtc *crtc,
struct drm_crtc_state *old_state)
{
- struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
- struct drm_device *dev = crtc->dev;
-
DRM_DEBUG_KMS("[CRTC:%d] crtc_atomic_flush.\n",
crtc->base.id);
- if (crtc->state->event) {
- unsigned long flags;
-
- crtc->state->event->pipe = drm_crtc_index(crtc);
-
- WARN_ON(drm_crtc_vblank_get(crtc) != 0);
-
- spin_lock_irqsave(&dev->event_lock, flags);
- vc4_crtc->event = crtc->state->event;
- crtc->state->event = NULL;
- spin_unlock_irqrestore(&dev->event_lock, flags);
- }
+ if (crtc->state->active && old_state->active && crtc->state->event)
+ vc4_crtc_consume_event(crtc);
}
static void vc4_crtc_handle_page_flip(struct vc4_crtc *vc4_crtc)