drm/radeon: Prevent too early kms-pageflips triggered by vblank.
Since 3.16-rc1 we have this new failure:
When the userspace XOrg ddx schedules vblank events to
trigger deferred kms-pageflips, e.g., via the OML_sync_control
extension call glXSwapBuffersMscOML(), or if a glXSwapBuffers()
is called immediately after completion of a previous swapbuffers
call, e.g., in a tight rendering loop with minimal rendering,
it happens frequently that the pageflip ioctl() is executed
within the same vblank in which a previous kms-pageflip completed,
or - for deferred swaps - always one vblank earlier than requested
by the client app.
This causes premature pageflips and detection of failure by
the ddx, e.g., XOrg log warnings like...
"(WW) RADEON(1): radeon_dri2_flip_event_handler: Pageflip
completion event has impossible msc 201025 < target_msc 201026"
... and error/invalid return values of glXWaitForSbcOML() and
Intel_swap_events extension.
Reason is the new way in which kms-pageflips are programmed
since 3.16.
This commit changes the time window in which the hw can
execute pending programmed pageflips. Before, a pending flip
would get executed anywhere within the vblank interval. Now
a pending flip only gets executed at the leading edge of
vblank (start of front porch), making sure that a invocation
of the pageflip ioctl() within a given vblank interval will
only lead to pageflip completion in the following vblank.
Tested to death on a DCE-4 card.
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c
index a03c734..30d242b 100644
--- a/drivers/gpu/drm/radeon/atombios_crtc.c
+++ b/drivers/gpu/drm/radeon/atombios_crtc.c
@@ -1414,8 +1414,8 @@
tmp &= ~EVERGREEN_GRPH_SURFACE_UPDATE_H_RETRACE_EN;
WREG32(EVERGREEN_GRPH_FLIP_CONTROL + radeon_crtc->crtc_offset, tmp);
- /* set pageflip to happen anywhere in vblank interval */
- WREG32(EVERGREEN_MASTER_UPDATE_MODE + radeon_crtc->crtc_offset, 0);
+ /* set pageflip to happen only at start of vblank interval (front porch) */
+ WREG32(EVERGREEN_MASTER_UPDATE_MODE + radeon_crtc->crtc_offset, 3);
if (!atomic && fb && fb != crtc->primary->fb) {
radeon_fb = to_radeon_framebuffer(fb);
@@ -1614,8 +1614,8 @@
tmp &= ~AVIVO_D1GRPH_SURFACE_UPDATE_H_RETRACE_EN;
WREG32(AVIVO_D1GRPH_FLIP_CONTROL + radeon_crtc->crtc_offset, tmp);
- /* set pageflip to happen anywhere in vblank interval */
- WREG32(AVIVO_D1MODE_MASTER_UPDATE_MODE + radeon_crtc->crtc_offset, 0);
+ /* set pageflip to happen only at start of vblank interval (front porch) */
+ WREG32(AVIVO_D1MODE_MASTER_UPDATE_MODE + radeon_crtc->crtc_offset, 3);
if (!atomic && fb && fb != crtc->primary->fb) {
radeon_fb = to_radeon_framebuffer(fb);
diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index f7ece0f..250bac3 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -2642,8 +2642,9 @@
for (i = 0; i < rdev->num_crtc; i++) {
if (save->crtc_enabled[i]) {
tmp = RREG32(EVERGREEN_MASTER_UPDATE_MODE + crtc_offsets[i]);
- if ((tmp & 0x3) != 0) {
- tmp &= ~0x3;
+ if ((tmp & 0x7) != 3) {
+ tmp &= ~0x7;
+ tmp |= 0x3;
WREG32(EVERGREEN_MASTER_UPDATE_MODE + crtc_offsets[i], tmp);
}
tmp = RREG32(EVERGREEN_GRPH_UPDATE + crtc_offsets[i]);
diff --git a/drivers/gpu/drm/radeon/evergreen_reg.h b/drivers/gpu/drm/radeon/evergreen_reg.h
index 333d143..23bff59 100644
--- a/drivers/gpu/drm/radeon/evergreen_reg.h
+++ b/drivers/gpu/drm/radeon/evergreen_reg.h
@@ -239,7 +239,6 @@
# define EVERGREEN_CRTC_V_BLANK (1 << 0)
#define EVERGREEN_CRTC_STATUS_POSITION 0x6e90
#define EVERGREEN_CRTC_STATUS_HV_COUNT 0x6ea0
-#define EVERGREEN_MASTER_UPDATE_MODE 0x6ef8
#define EVERGREEN_CRTC_UPDATE_LOCK 0x6ed4
#define EVERGREEN_MASTER_UPDATE_LOCK 0x6ef4
#define EVERGREEN_MASTER_UPDATE_MODE 0x6ef8
diff --git a/drivers/gpu/drm/radeon/rv515.c b/drivers/gpu/drm/radeon/rv515.c
index 237dd29..3e21e86 100644
--- a/drivers/gpu/drm/radeon/rv515.c
+++ b/drivers/gpu/drm/radeon/rv515.c
@@ -406,8 +406,9 @@
for (i = 0; i < rdev->num_crtc; i++) {
if (save->crtc_enabled[i]) {
tmp = RREG32(AVIVO_D1MODE_MASTER_UPDATE_MODE + crtc_offsets[i]);
- if ((tmp & 0x3) != 0) {
- tmp &= ~0x3;
+ if ((tmp & 0x7) != 3) {
+ tmp &= ~0x7;
+ tmp |= 0x3;
WREG32(AVIVO_D1MODE_MASTER_UPDATE_MODE + crtc_offsets[i], tmp);
}
tmp = RREG32(AVIVO_D1GRPH_UPDATE + crtc_offsets[i]);