drm/radeon: fix a semaphore deadlock on pre cayman asics

The out of order execution of semaphore commands on
pre cayman asics doesn't work correctly and can
cause deadlocks, so turn it off for now.

Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index fbcd84803b60..17ca72ce3027 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -2362,6 +2362,9 @@ void r600_semaphore_ring_emit(struct radeon_device *rdev,
         uint64_t addr = semaphore->gpu_addr;
         unsigned sel = emit_wait ? PACKET3_SEM_SEL_WAIT : PACKET3_SEM_SEL_SIGNAL;
 
+        if (rdev->family < CHIP_CAYMAN)
+                sel |= PACKET3_SEM_WAIT_ON_SIGNAL;
+
         radeon_ring_write(ring, PACKET3(PACKET3_MEM_SEMAPHORE, 1));
         radeon_ring_write(ring, addr & 0xffffffff);
         radeon_ring_write(ring, (upper_32_bits(addr) & 0xff) | sel);