[PATCH 3.13.y-ckt 041/139] drm/radeon: work around a hw bug in MGCG on CIK

From: Kamal Mostafa
Date: Wed Jan 28 2015 - 22:22:47 EST


3.13.11-ckt15 -stable review patch. If anyone has any objections, please let me know.

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

From: Alex Deucher <alexander.deucher@xxxxxxx>

commit 4bb62c95a7e781a238b2ab374f34b1bf91e01ddc upstream.

Always need to set bit 0 of RLC_CGTT_MGCG_OVERRIDE
to avoid unreliable doorbell updates in some cases.

Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/gpu/drm/radeon/cik.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index 642eed1..e205912 100644
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -5676,6 +5676,7 @@ static void cik_enable_mgcg(struct radeon_device *rdev, bool enable)
}

orig = data = RREG32(RLC_CGTT_MGCG_OVERRIDE);
+ data |= 0x00000001;
data &= 0xfffffffd;
if (orig != data)
WREG32(RLC_CGTT_MGCG_OVERRIDE, data);
@@ -5707,7 +5708,7 @@ static void cik_enable_mgcg(struct radeon_device *rdev, bool enable)
}
} else {
orig = data = RREG32(RLC_CGTT_MGCG_OVERRIDE);
- data |= 0x00000002;
+ data |= 0x00000003;
if (orig != data)
WREG32(RLC_CGTT_MGCG_OVERRIDE, data);

--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/