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>

2 files changed, 4 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index fbcd84803b6..17ca72ce302 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);
diff --git a/drivers/gpu/drm/radeon/r600d.h b/drivers/gpu/drm/radeon/r600d.h
index 3ee1fd7ef39..9b23670716f 100644
--- a/drivers/gpu/drm/radeon/r600d.h
+++ b/drivers/gpu/drm/radeon/r600d.h
@@ -831,6 +831,7 @@
 #define PACKET3_STRMOUT_BUFFER_UPDATE                   0x34
 #define PACKET3_INDIRECT_BUFFER_MP                      0x38
 #define PACKET3_MEM_SEMAPHORE                           0x39
+#              define PACKET3_SEM_WAIT_ON_SIGNAL    (0x1 << 12)
 #              define PACKET3_SEM_SEL_SIGNAL        (0x6 << 29)
 #              define PACKET3_SEM_SEL_WAIT          (0x7 << 29)
 #define PACKET3_MPEG_INDEX                              0x3A