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/rs400.c b/drivers/gpu/drm/radeon/rs400.c
index b8074a8..9566b59 100644
--- a/drivers/gpu/drm/radeon/rs400.c
+++ b/drivers/gpu/drm/radeon/rs400.c
@@ -274,19 +274,26 @@
uint32_t rs400_mc_rreg(struct radeon_device *rdev, uint32_t reg)
{
+ unsigned long flags;
uint32_t r;
+ spin_lock_irqsave(&rdev->mc_idx_lock, flags);
WREG32(RS480_NB_MC_INDEX, reg & 0xff);
r = RREG32(RS480_NB_MC_DATA);
WREG32(RS480_NB_MC_INDEX, 0xff);
+ spin_unlock_irqrestore(&rdev->mc_idx_lock, flags);
return r;
}
void rs400_mc_wreg(struct radeon_device *rdev, uint32_t reg, uint32_t v)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rdev->mc_idx_lock, flags);
WREG32(RS480_NB_MC_INDEX, ((reg) & 0xff) | RS480_NB_MC_IND_WR_EN);
WREG32(RS480_NB_MC_DATA, (v));
WREG32(RS480_NB_MC_INDEX, 0xff);
+ spin_unlock_irqrestore(&rdev->mc_idx_lock, flags);
}
#if defined(CONFIG_DEBUG_FS)