drm/radeon: add spinlocks for indirect register accesss
This adds spinlocks to protect access to other
indirect register apertures. These indirect spaces are
used pretty infrequently and we haven't had an reported
problems, but better safe than sorry.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/r420.c b/drivers/gpu/drm/radeon/r420.c
index 4e796ec..6edf2b3 100644
--- a/drivers/gpu/drm/radeon/r420.c
+++ b/drivers/gpu/drm/radeon/r420.c
@@ -160,18 +160,25 @@
u32 r420_mc_rreg(struct radeon_device *rdev, u32 reg)
{
+ unsigned long flags;
u32 r;
+ spin_lock_irqsave(&rdev->mc_idx_lock, flags);
WREG32(R_0001F8_MC_IND_INDEX, S_0001F8_MC_IND_ADDR(reg));
r = RREG32(R_0001FC_MC_IND_DATA);
+ spin_unlock_irqrestore(&rdev->mc_idx_lock, flags);
return r;
}
void r420_mc_wreg(struct radeon_device *rdev, u32 reg, u32 v)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rdev->mc_idx_lock, flags);
WREG32(R_0001F8_MC_IND_INDEX, S_0001F8_MC_IND_ADDR(reg) |
S_0001F8_MC_IND_WR_EN(1));
WREG32(R_0001FC_MC_IND_DATA, v);
+ spin_unlock_irqrestore(&rdev->mc_idx_lock, flags);
}
static void r420_debugfs(struct radeon_device *rdev)