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path: root/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
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Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_display.c')
-rw-r--r--drivers/gpu/drm/amd/amdgpu/amdgpu_display.c108
1 files changed, 79 insertions, 29 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
index e173a5a02f0d..5580d3420c3a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -73,6 +73,8 @@ static void amdgpu_flip_work_func(struct work_struct *__work)
struct drm_crtc *crtc = &amdgpuCrtc->base;
unsigned long flags;
unsigned i;
+ int vpos, hpos, stat, min_udelay;
+ struct drm_vblank_crtc *vblank = &crtc->dev->vblank[work->crtc_id];
amdgpu_flip_wait_fence(adev, &work->excl);
for (i = 0; i < work->shared_count; ++i)
@@ -81,6 +83,41 @@ static void amdgpu_flip_work_func(struct work_struct *__work)
/* We borrow the event spin lock for protecting flip_status */
spin_lock_irqsave(&crtc->dev->event_lock, flags);
+ /* If this happens to execute within the "virtually extended" vblank
+ * interval before the start of the real vblank interval then it needs
+ * to delay programming the mmio flip until the real vblank is entered.
+ * This prevents completing a flip too early due to the way we fudge
+ * our vblank counter and vblank timestamps in order to work around the
+ * problem that the hw fires vblank interrupts before actual start of
+ * vblank (when line buffer refilling is done for a frame). It
+ * complements the fudging logic in amdgpu_get_crtc_scanoutpos() for
+ * timestamping and amdgpu_get_vblank_counter_kms() for vblank counts.
+ *
+ * In practice this won't execute very often unless on very fast
+ * machines because the time window for this to happen is very small.
+ */
+ for (;;) {
+ /* GET_DISTANCE_TO_VBLANKSTART returns distance to real vblank
+ * start in hpos, and to the "fudged earlier" vblank start in
+ * vpos.
+ */
+ stat = amdgpu_get_crtc_scanoutpos(adev->ddev, work->crtc_id,
+ GET_DISTANCE_TO_VBLANKSTART,
+ &vpos, &hpos, NULL, NULL,
+ &crtc->hwmode);
+
+ if ((stat & (DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_ACCURATE)) !=
+ (DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_ACCURATE) ||
+ !(vpos >= 0 && hpos <= 0))
+ break;
+
+ /* Sleep at least until estimated real start of hw vblank */
+ spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
+ min_udelay = (-hpos + 1) * max(vblank->linedur_ns / 1000, 5);
+ usleep_range(min_udelay, 2 * min_udelay);
+ spin_lock_irqsave(&crtc->dev->event_lock, flags);
+ };
+
/* do the flip (mmio) */
adev->mode_info.funcs->page_flip(adev, work->crtc_id, work->base);
/* set the flip status */
@@ -109,7 +146,7 @@ static void amdgpu_unpin_work_func(struct work_struct *__work)
} else
DRM_ERROR("failed to reserve buffer after flip\n");
- drm_gem_object_unreference_unlocked(&work->old_rbo->gem_base);
+ amdgpu_bo_unref(&work->old_rbo);
kfree(work->shared);
kfree(work);
}
@@ -148,8 +185,8 @@ int amdgpu_crtc_page_flip(struct drm_crtc *crtc,
obj = old_amdgpu_fb->obj;
/* take a reference to the old object */
- drm_gem_object_reference(obj);
work->old_rbo = gem_to_amdgpu_bo(obj);
+ amdgpu_bo_ref(work->old_rbo);
new_amdgpu_fb = to_amdgpu_framebuffer(fb);
obj = new_amdgpu_fb->obj;
@@ -222,7 +259,7 @@ pflip_cleanup:
amdgpu_bo_unreserve(new_rbo);
cleanup:
- drm_gem_object_unreference_unlocked(&work->old_rbo->gem_base);
+ amdgpu_bo_unref(&work->old_rbo);
fence_put(work->excl);
for (i = 0; i < work->shared_count; ++i)
fence_put(work->shared[i]);
@@ -712,6 +749,15 @@ bool amdgpu_crtc_scaling_mode_fixup(struct drm_crtc *crtc,
* \param dev Device to query.
* \param pipe Crtc to query.
* \param flags Flags from caller (DRM_CALLED_FROM_VBLIRQ or 0).
+ * For driver internal use only also supports these flags:
+ *
+ * USE_REAL_VBLANKSTART to use the real start of vblank instead
+ * of a fudged earlier start of vblank.
+ *
+ * GET_DISTANCE_TO_VBLANKSTART to return distance to the
+ * fudged earlier start of vblank in *vpos and the distance
+ * to true start of vblank in *hpos.
+ *
* \param *vpos Location where vertical scanout position should be stored.
* \param *hpos Location where horizontal scanout position should go.
* \param *stime Target location for timestamp taken immediately before
@@ -776,10 +822,40 @@ int amdgpu_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
vbl_end = 0;
}
+ /* Called from driver internal vblank counter query code? */
+ if (flags & GET_DISTANCE_TO_VBLANKSTART) {
+ /* Caller wants distance from real vbl_start in *hpos */
+ *hpos = *vpos - vbl_start;
+ }
+
+ /* Fudge vblank to start a few scanlines earlier to handle the
+ * problem that vblank irqs fire a few scanlines before start
+ * of vblank. Some driver internal callers need the true vblank
+ * start to be used and signal this via the USE_REAL_VBLANKSTART flag.
+ *
+ * The cause of the "early" vblank irq is that the irq is triggered
+ * by the line buffer logic when the line buffer read position enters
+ * the vblank, whereas our crtc scanout position naturally lags the
+ * line buffer read position.
+ */
+ if (!(flags & USE_REAL_VBLANKSTART))
+ vbl_start -= adev->mode_info.crtcs[pipe]->lb_vblank_lead_lines;
+
/* Test scanout position against vblank region. */
if ((*vpos < vbl_start) && (*vpos >= vbl_end))
in_vbl = false;
+ /* In vblank? */
+ if (in_vbl)
+ ret |= DRM_SCANOUTPOS_IN_VBLANK;
+
+ /* Called from driver internal vblank counter query code? */
+ if (flags & GET_DISTANCE_TO_VBLANKSTART) {
+ /* Caller wants distance from fudged earlier vbl_start */
+ *vpos -= vbl_start;
+ return ret;
+ }
+
/* Check if inside vblank area and apply corrective offsets:
* vpos will then be >=0 in video scanout area, but negative
* within vblank area, counting down the number of lines until
@@ -795,32 +871,6 @@ int amdgpu_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
/* Correct for shifted end of vbl at vbl_end. */
*vpos = *vpos - vbl_end;
- /* In vblank? */
- if (in_vbl)
- ret |= DRM_SCANOUTPOS_IN_VBLANK;
-
- /* Is vpos outside nominal vblank area, but less than
- * 1/100 of a frame height away from start of vblank?
- * If so, assume this isn't a massively delayed vblank
- * interrupt, but a vblank interrupt that fired a few
- * microseconds before true start of vblank. Compensate
- * by adding a full frame duration to the final timestamp.
- * Happens, e.g., on ATI R500, R600.
- *
- * We only do this if DRM_CALLED_FROM_VBLIRQ.
- */
- if ((flags & DRM_CALLED_FROM_VBLIRQ) && !in_vbl) {
- vbl_start = mode->crtc_vdisplay;
- vtotal = mode->crtc_vtotal;
-
- if (vbl_start - *vpos < vtotal / 100) {
- *vpos -= vtotal;
-
- /* Signal this correction as "applied". */
- ret |= 0x8;
- }
- }
-
return ret;
}