/**
* amdgpu_get_vblank_counter_kms - get frame count
*
* @dev: drm dev pointer
* @pipe: crtc to get the frame count from
*
* Gets the frame count on the requested crtc (all asics).
* Returns frame count on success, -EINVAL on failure.
*/
u32 amdgpu_get_vblank_counter_kms(struct drm_device *dev, unsigned int pipe)
{
struct amdgpu_device *adev = dev->dev_private;
int vpos, hpos, stat;
u32 count;
if (pipe >= adev->mode_info.num_crtc) {
DRM_ERROR("Invalid crtc %u\n", pipe);
return -EINVAL;
}
/* The hw increments its frame counter at start of vsync, not at start
* of vblank, as is required by DRM core vblank counter handling.
* Cook the hw count here to make it appear to the caller as if it
* incremented at start of vblank. We measure distance to start of
* vblank in vpos. vpos therefore will be >= 0 between start of vblank
* and start of vsync, so vpos >= 0 means to bump the hw frame counter
* result by 1 to give the proper appearance to caller.
*/
if (adev->mode_info.crtcs[pipe]) {
/* Repeat readout if needed to provide stable result if
* we cross start of vsync during the queries.
*/
do {
count = amdgpu_display_vblank_get_counter(adev, pipe);
/* Ask amdgpu_get_crtc_scanoutpos to return vpos as
* distance to start of vblank, instead of regular
* vertical scanout pos.
*/
stat = amdgpu_get_crtc_scanoutpos(
dev, pipe, GET_DISTANCE_TO_VBLANKSTART,
&vpos, &hpos, NULL, NULL,
&adev->mode_info.crtcs[pipe]->base.hwmode);
} while (count != amdgpu_display_vblank_get_counter(adev, pipe));
if (((stat & (DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_ACCURATE)) !=
(DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_ACCURATE))) {
DRM_DEBUG_VBL("Query failed! stat %d\n", stat);
} else {
DRM_DEBUG_VBL("crtc %d: dist from vblank start %d\n",
pipe, vpos);
/* Bump counter if we are at >= leading edge of vblank,
* but before vsync where vpos would turn negative and
* the hw counter really increments.
*/
if (vpos >= 0)
count++;
}
} else {
/* Fallback to use value as is. */
count = amdgpu_display_vblank_get_counter(adev, pipe);
DRM_DEBUG_VBL("NULL mode info! Returned count may be wrong.\n");
}
return count;
}
/**
* amdgpu_get_vblank_counter_kms - get frame count
*
* @dev: drm dev pointer
* @crtc: crtc to get the frame count from
*
* Gets the frame count on the requested crtc (all asics).
* Returns frame count on success, -EINVAL on failure.
*/
u32 amdgpu_get_vblank_counter_kms(struct drm_device *dev, int crtc)
{
struct amdgpu_device *adev = dev->dev_private;
if (crtc < 0 || crtc >= adev->mode_info.num_crtc) {
DRM_ERROR("Invalid crtc %d\n", crtc);
return -EINVAL;
}
return amdgpu_display_vblank_get_counter(adev, crtc);
}
