From f53f81b2576a9bd3af947e2b1c3a46dfab51c5ef Mon Sep 17 00:00:00 2001 From: Mario Kleiner Date: Thu, 3 Jul 2014 03:45:02 +0200 Subject: 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 Signed-off-by: Alex Deucher --- drivers/gpu/drm/radeon/rv515.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/gpu/drm/radeon/rv515.c') diff --git a/drivers/gpu/drm/radeon/rv515.c b/drivers/gpu/drm/radeon/rv515.c index 237dd29d9f1c..3e21e869015f 100644 --- a/drivers/gpu/drm/radeon/rv515.c +++ b/drivers/gpu/drm/radeon/rv515.c @@ -406,8 +406,9 @@ void rv515_mc_resume(struct radeon_device *rdev, struct rv515_mc_save *save) 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]); -- cgit v1.2.3