On Mon, Nov 12, 2018 at 06:59:45PM +0200, Ville Syrjala wrote:
From: Ville Syrjälä ville.syrjala@linux.intel.com
On i965gm we need to adjust max_vblank_count dynamically depending on whether the TV encoder is used or not. To that end add a per-crtc max_vblank_count that takes precedence over its device wide counterpart. The driver can now call drm_crtc_set_max_vblank_count() to configure the per-crtc value before calling drm_vblank_on().
Also looks like there was some discussion about exynos needing similar treatment.
Cc: stable@vger.kernel.org Cc: Inki Dae inki.dae@samsung.com Cc: Daniel Vetter daniel@ffwll.ch Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com
drivers/gpu/drm/drm_vblank.c | 39 ++++++++++++++++++++++++++++++++---- include/drm/drm_vblank.h | 8 ++++++++ 2 files changed, 43 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index 98e091175921..c3abbdca8aba 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -105,13 +105,20 @@ static void store_vblank(struct drm_device *dev, unsigned int pipe, write_sequnlock(&vblank->seqlock); } +static u32 drm_max_vblank_count(struct drm_device *dev, unsigned int pipe) +{
- struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
- return vblank->max_vblank_count ?: dev->max_vblank_count;
+}
/*
- "No hw counter" fallback implementation of .get_vblank_counter() hook,
- if there is no useable hardware frame counter available.
*/ static u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe) {
- WARN_ON_ONCE(dev->max_vblank_count != 0);
- WARN_ON_ONCE(drm_max_vblank_count(dev, pipe) != 0); return 0;
} @@ -198,6 +205,7 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, ktime_t t_vblank; int count = DRM_TIMESTAMP_MAXRETRIES; int framedur_ns = vblank->framedur_ns;
- u32 max_vblank_count = drm_max_vblank_count(dev, pipe);
/* * Interrupts were disabled prior to this call, so deal with counter @@ -216,9 +224,9 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, in_vblank_irq); } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
- if (dev->max_vblank_count != 0) {
- if (max_vblank_count) { /* trust the hw counter when it's around */
diff = (cur_vblank - vblank->last) & dev->max_vblank_count;
diff = (cur_vblank - vblank->last) & max_vblank_count;@@ -258,7 +266,8 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, pipe, vblank->count, diff, cur_vblank, vblank->last); if (diff == 0) {
WARN_ON_ONCE(cur_vblank != vblank->last);
WARN_ON_ONCE(max_vblank_count &&cur_vblank != vblank->last);
Unrelated bugfix for this warning? Should be a separate patch I think, or I'm missing something.
return;} @@ -1204,6 +1213,28 @@ void drm_crtc_vblank_reset(struct drm_crtc *crtc) } EXPORT_SYMBOL(drm_crtc_vblank_reset); +/**
- drm_crtc_set_max_vblank_count - configure the hw max vblank counter value
- @crtc: CRTC in question
- @max_vblank_count: max hardware vblank counter value
- Update the maximum hardware vblank counter value for @crtc. Useful
- for hardware where the operation of the hardware vblank counter
- depends on the active display configuration.
- If used, must be called before drm_vblank_on().
I think we should check this at runtime with a WARN_ON. Plus make the comment here a bit clearer that this is indeed for runtime adjusting of the max_vblank_count, in cases where that depends upon the connected outputs.
- */
+void drm_crtc_set_max_vblank_count(struct drm_crtc *crtc,
u32 max_vblank_count)+{
- struct drm_device *dev = crtc->dev;
- unsigned int pipe = drm_crtc_index(crtc);
- struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
- vblank->max_vblank_count = max_vblank_count;
+} +EXPORT_SYMBOL(drm_crtc_set_max_vblank_count);
/**
- drm_crtc_vblank_on - enable vblank events on a CRTC
- @crtc: CRTC in question
diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h index 6ad9630d4f48..ecb2cf9913e2 100644 --- a/include/drm/drm_vblank.h +++ b/include/drm/drm_vblank.h @@ -128,6 +128,12 @@ struct drm_vblank_crtc { * @last: Protected by &drm_device.vbl_lock, used for wraparound handling. */ u32 last;
- /**
* @max_vblank_count: Maximum value of the hardware vblank counter.* If non-zero this takes precedence over &drm_device.max_vblank_count* for this crtc. Otherwise &drm_device.max_vblank_count is used.*/
I'd add "This should be set by calling drm_crtc_set_max_vblank_count()."
And please also add a note to the kerneldoc of drm_driver.max_vblank_count pointing at &drm_vblank_crtc.max_vblank_count for per-crtc limits.
Aside from the nits lgtm. I think I'll skip looking at the TV out stuff though ...
Cheers, Daniel
- u32 max_vblank_count; /**
- @inmodeset: Tracks whether the vblank is disabled due to a modeset.
- For legacy driver bit 2 additionally tracks whether an additional
@@ -206,4 +212,6 @@ bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, void drm_calc_timestamping_constants(struct drm_crtc *crtc, const struct drm_display_mode *mode); wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc); +void drm_crtc_set_max_vblank_count(struct drm_crtc *crtc,
u32 max_vblank_count);#endif
2.18.1