drm/radeon: fix & improve ih ring handling v3
The spinlock was actually there to protect the
rptr, but rptr was read outside of the locked area.
Also we don't really need a spinlock here, an
atomic should to quite fine since we only need to
prevent it from being reentrant.
v2: Keep the spinlock....
v3: Back to an atomic again after finding & fixing the real bug.
Signed-off-by: Christian Koenig <christian.koenig@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 7667184..3c563d1 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -731,8 +731,7 @@
radeon_mutex_init(&rdev->cs_mutex);
mutex_init(&rdev->ring_lock);
mutex_init(&rdev->dc_hw_i2c_mutex);
- if (rdev->family >= CHIP_R600)
- spin_lock_init(&rdev->ih.lock);
+ atomic_set(&rdev->ih.lock, 0);
mutex_init(&rdev->gem.mutex);
mutex_init(&rdev->pm.mutex);
init_rwsem(&rdev->pm.mclk_lock);