drm/radeon/kms: add support for semaphores v3

They are used to sync between rings, while fences
sync between a ring and the cpu.

v2 Fix radeon_semaphore_driver_fini when no semaphore were
allocated.

v3 Initialize list early on to avoid issue in case or early
error

Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index d2dced5679b5..2f18163e5e32 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -832,6 +832,14 @@ void r100_fence_ring_emit(struct radeon_device *rdev,
         radeon_ring_write(rdev, RADEON_SW_INT_FIRE);
 }
 
+void r100_semaphore_ring_emit(struct radeon_device *rdev,
+                              struct radeon_semaphore *semaphore,
+                              unsigned ring, bool emit_wait)
+{
+        /* Unused on older asics, since we don't have semaphores or multiple rings */
+        BUG();
+}
+
 int r100_copy_blit(struct radeon_device *rdev,
                    uint64_t src_offset,
                    uint64_t dst_offset,