drm/i915: Improve gen3/4 frame counter

Currently the logic to fix up the frame counter on gen3/4 assumes that
start of vblank occurs at vblank_start*htotal pixels, when in fact
it occurs htotal-hsync_start pixels earlier. Apply the appropriate
adjustment to make the frame counter more accurate.

Also fix the vblank start position for interlaced display modes.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: "Akash Goel <akash.goels@gmail.com>"
Reviewed-by: "Sourab Gupta <sourabgupta@gmail.com>"
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Ville Syrjälä 2014-04-29 13:35:50 +03:00 committed by Daniel Vetter
parent 7e78f1cb38
commit 0b2a8e09f9

View file

@ -754,7 +754,7 @@ static u32 i915_get_vblank_counter(struct drm_device *dev, int pipe)
struct drm_i915_private *dev_priv = dev->dev_private;
unsigned long high_frame;
unsigned long low_frame;
u32 high1, high2, low, pixel, vbl_start;
u32 high1, high2, low, pixel, vbl_start, hsync_start, htotal;
if (!i915_pipe_enabled(dev, pipe)) {
DRM_DEBUG_DRIVER("trying to get vblank count for disabled "
@ -768,17 +768,28 @@ static u32 i915_get_vblank_counter(struct drm_device *dev, int pipe)
const struct drm_display_mode *mode =
&intel_crtc->config.adjusted_mode;
vbl_start = mode->crtc_vblank_start * mode->crtc_htotal;
htotal = mode->crtc_htotal;
hsync_start = mode->crtc_hsync_start;
vbl_start = mode->crtc_vblank_start;
if (mode->flags & DRM_MODE_FLAG_INTERLACE)
vbl_start = DIV_ROUND_UP(vbl_start, 2);
} else {
enum transcoder cpu_transcoder = (enum transcoder) pipe;
u32 htotal;
htotal = ((I915_READ(HTOTAL(cpu_transcoder)) >> 16) & 0x1fff) + 1;
hsync_start = (I915_READ(HSYNC(cpu_transcoder)) & 0x1fff) + 1;
vbl_start = (I915_READ(VBLANK(cpu_transcoder)) & 0x1fff) + 1;
vbl_start *= htotal;
if ((I915_READ(PIPECONF(cpu_transcoder)) &
PIPECONF_INTERLACE_MASK) != PIPECONF_PROGRESSIVE)
vbl_start = DIV_ROUND_UP(vbl_start, 2);
}
/* Convert to pixel count */
vbl_start *= htotal;
/* Start of vblank event occurs at start of hsync */
vbl_start -= htotal - hsync_start;
high_frame = PIPEFRAME(pipe);
low_frame = PIPEFRAMEPIXEL(pipe);