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path: root/drivers/gpu/drm/drm_vblank.c
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Diffstat (limited to 'drivers/gpu/drm/drm_vblank.c')
-rw-r--r--drivers/gpu/drm/drm_vblank.c100
1 files changed, 88 insertions, 12 deletions
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index 32d9bcf5be7f..28cdcf76b6f9 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -120,6 +120,9 @@ static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe)
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+ if (WARN_ON(!crtc))
+ return 0;
+
if (crtc->funcs->get_vblank_counter)
return crtc->funcs->get_vblank_counter(crtc);
}
@@ -271,7 +274,7 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
store_vblank(dev, pipe, diff, t_vblank, cur_vblank);
}
-static u32 drm_vblank_count(struct drm_device *dev, unsigned int pipe)
+static u64 drm_vblank_count(struct drm_device *dev, unsigned int pipe)
{
struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
@@ -292,11 +295,11 @@ static u32 drm_vblank_count(struct drm_device *dev, unsigned int pipe)
* This is mostly useful for hardware that can obtain the scanout position, but
* doesn't have a hardware frame counter.
*/
-u32 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc)
+u64 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
unsigned int pipe = drm_crtc_index(crtc);
- u32 vblank;
+ u64 vblank;
unsigned long flags;
WARN_ONCE(drm_debug & DRM_UT_VBL && !dev->driver->get_vblank_timestamp,
@@ -318,6 +321,9 @@ static void __disable_vblank(struct drm_device *dev, unsigned int pipe)
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+ if (WARN_ON(!crtc))
+ return;
+
if (crtc->funcs->disable_vblank) {
crtc->funcs->disable_vblank(crtc);
return;
@@ -347,23 +353,25 @@ void drm_vblank_disable_and_save(struct drm_device *dev, unsigned int pipe)
spin_lock_irqsave(&dev->vblank_time_lock, irqflags);
/*
- * Only disable vblank interrupts if they're enabled. This avoids
- * calling the ->disable_vblank() operation in atomic context with the
- * hardware potentially runtime suspended.
+ * Update vblank count and disable vblank interrupts only if the
+ * interrupts were enabled. This avoids calling the ->disable_vblank()
+ * operation in atomic context with the hardware potentially runtime
+ * suspended.
*/
- if (vblank->enabled) {
- __disable_vblank(dev, pipe);
- vblank->enabled = false;
- }
+ if (!vblank->enabled)
+ goto out;
/*
- * Always update the count and timestamp to maintain the
+ * Update the count and timestamp to maintain the
* appearance that the counter has been ticking all along until
* this time. This makes the count account for the entire time
* between drm_crtc_vblank_on() and drm_crtc_vblank_off().
*/
drm_update_vblank_count(dev, pipe, false);
+ __disable_vblank(dev, pipe);
+ vblank->enabled = false;
+out:
spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags);
}
@@ -918,6 +926,9 @@ static int __enable_vblank(struct drm_device *dev, unsigned int pipe)
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+ if (WARN_ON(!crtc))
+ return 0;
+
if (crtc->funcs->enable_vblank)
return crtc->funcs->enable_vblank(crtc);
}
@@ -1055,7 +1066,7 @@ void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe)
{
struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
int ret;
- u32 last;
+ u64 last;
if (WARN_ON(pipe >= dev->num_crtcs))
return;
@@ -1235,6 +1246,71 @@ void drm_crtc_vblank_on(struct drm_crtc *crtc)
}
EXPORT_SYMBOL(drm_crtc_vblank_on);
+/**
+ * drm_vblank_restore - estimate missed vblanks and update vblank count.
+ * @dev: DRM device
+ * @pipe: CRTC index
+ *
+ * Power manamement features can cause frame counter resets between vblank
+ * disable and enable. Drivers can use this function in their
+ * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since
+ * the last &drm_crtc_funcs.disable_vblank using timestamps and update the
+ * vblank counter.
+ *
+ * This function is the legacy version of drm_crtc_vblank_restore().
+ */
+void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
+{
+ ktime_t t_vblank;
+ struct drm_vblank_crtc *vblank;
+ int framedur_ns;
+ u64 diff_ns;
+ u32 cur_vblank, diff = 1;
+ int count = DRM_TIMESTAMP_MAXRETRIES;
+
+ if (WARN_ON(pipe >= dev->num_crtcs))
+ return;
+
+ assert_spin_locked(&dev->vbl_lock);
+ assert_spin_locked(&dev->vblank_time_lock);
+
+ vblank = &dev->vblank[pipe];
+ WARN_ONCE((drm_debug & DRM_UT_VBL) && !vblank->framedur_ns,
+ "Cannot compute missed vblanks without frame duration\n");
+ framedur_ns = vblank->framedur_ns;
+
+ do {
+ cur_vblank = __get_vblank_counter(dev, pipe);
+ drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false);
+ } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+
+ diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time));
+ if (framedur_ns)
+ diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns);
+
+
+ DRM_DEBUG_VBL("missed %d vblanks in %lld ns, frame duration=%d ns, hw_diff=%d\n",
+ diff, diff_ns, framedur_ns, cur_vblank - vblank->last);
+ store_vblank(dev, pipe, diff, t_vblank, cur_vblank);
+}
+EXPORT_SYMBOL(drm_vblank_restore);
+
+/**
+ * drm_crtc_vblank_restore - estimate missed vblanks and update vblank count.
+ * @crtc: CRTC in question
+ *
+ * Power manamement features can cause frame counter resets between vblank
+ * disable and enable. Drivers can use this function in their
+ * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since
+ * the last &drm_crtc_funcs.disable_vblank using timestamps and update the
+ * vblank counter.
+ */
+void drm_crtc_vblank_restore(struct drm_crtc *crtc)
+{
+ drm_vblank_restore(crtc->dev, drm_crtc_index(crtc));
+}
+EXPORT_SYMBOL(drm_crtc_vblank_restore);
+
static void drm_legacy_vblank_pre_modeset(struct drm_device *dev,
unsigned int pipe)
{