[ 48/73] drm/radeon: update wait_for_vblank for r5xx-r7xx

From: Greg Kroah-Hartman
Date: Thu May 09 2013 - 18:32:33 EST


3.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Alex Deucher <alexander.deucher@xxxxxxx>

commit bea5497bfc1067620c8c8e9d37a42e0bb6d7d7fa upstream.

Properly wait for the next vblank region. The previous
code didn't always wait long enough depending on the timing.

Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/radeon/rs600.c | 52 ++++++++++++++++++++++++++++++++++-------
1 file changed, 44 insertions(+), 8 deletions(-)

--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -52,23 +52,59 @@ static const u32 crtc_offsets[2] =
AVIVO_D2CRTC_H_TOTAL - AVIVO_D1CRTC_H_TOTAL
};

+static bool avivo_is_in_vblank(struct radeon_device *rdev, int crtc)
+{
+ if (RREG32(AVIVO_D1CRTC_STATUS + crtc_offsets[crtc]) & AVIVO_D1CRTC_V_BLANK)
+ return true;
+ else
+ return false;
+}
+
+static bool avivo_is_counter_moving(struct radeon_device *rdev, int crtc)
+{
+ u32 pos1, pos2;
+
+ pos1 = RREG32(AVIVO_D1CRTC_STATUS_POSITION + crtc_offsets[crtc]);
+ pos2 = RREG32(AVIVO_D1CRTC_STATUS_POSITION + crtc_offsets[crtc]);
+
+ if (pos1 != pos2)
+ return true;
+ else
+ return false;
+}
+
+/**
+ * avivo_wait_for_vblank - vblank wait asic callback.
+ *
+ * @rdev: radeon_device pointer
+ * @crtc: crtc to wait for vblank on
+ *
+ * Wait for vblank on the requested crtc (r5xx-r7xx).
+ */
void avivo_wait_for_vblank(struct radeon_device *rdev, int crtc)
{
- int i;
+ unsigned i = 0;

if (crtc >= rdev->num_crtc)
return;

- if (RREG32(AVIVO_D1CRTC_CONTROL + crtc_offsets[crtc]) & AVIVO_CRTC_EN) {
- for (i = 0; i < rdev->usec_timeout; i++) {
- if (!(RREG32(AVIVO_D1CRTC_STATUS + crtc_offsets[crtc]) & AVIVO_D1CRTC_V_BLANK))
+ if (!(RREG32(AVIVO_D1CRTC_CONTROL + crtc_offsets[crtc]) & AVIVO_CRTC_EN))
+ return;
+
+ /* depending on when we hit vblank, we may be close to active; if so,
+ * wait for another frame.
+ */
+ while (avivo_is_in_vblank(rdev, crtc)) {
+ if (i++ % 100 == 0) {
+ if (!avivo_is_counter_moving(rdev, crtc))
break;
- udelay(1);
}
- for (i = 0; i < rdev->usec_timeout; i++) {
- if (RREG32(AVIVO_D1CRTC_STATUS + crtc_offsets[crtc]) & AVIVO_D1CRTC_V_BLANK)
+ }
+
+ while (!avivo_is_in_vblank(rdev, crtc)) {
+ if (i++ % 100 == 0) {
+ if (!avivo_is_counter_moving(rdev, crtc))
break;
- udelay(1);
}
}
}


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