From 812d046915f48236657f02c06d7dc47140e9ceda Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Mon, 26 Jul 2010 18:51:53 -0400 Subject: drm/radeon/kms/r7xx: add workaround for hw issue with HDP flush Use of HDP_*_COHERENCY_FLUSH_CNTL can cause a hang in certain situations. Add workaround. Signed-off-by: Alex Deucher Cc: stable@kernel.org Signed-off-by: Dave Airlie --- drivers/gpu/drm/radeon/rv770.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/radeon/rv770.c') diff --git a/drivers/gpu/drm/radeon/rv770.c b/drivers/gpu/drm/radeon/rv770.c index 236fe6681922..f1c796810117 100644 --- a/drivers/gpu/drm/radeon/rv770.c +++ b/drivers/gpu/drm/radeon/rv770.c @@ -204,7 +204,10 @@ static void rv770_mc_program(struct radeon_device *rdev) WREG32((0x2c20 + j), 0x00000000); WREG32((0x2c24 + j), 0x00000000); } - WREG32(HDP_REG_COHERENCY_FLUSH_CNTL, 0); + /* r7xx hw bug. Read from HDP_DEBUG1 rather + * than writing to HDP_REG_COHERENCY_FLUSH_CNTL + */ + tmp = RREG32(HDP_DEBUG1); rv515_mc_stop(rdev, &save); if (r600_mc_wait_for_idle(rdev)) { -- cgit v1.2.3