drm/radeon: fix fence value access

It is possible that radeon_fence_process is called
after writeback is disabled for suspend, leading
to an invalid read of register 0x0.

This fixes a problem for me where the fence value
is temporary incremented by 0x100000000 on
suspend/resume.

Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Christian König 2012-07-09 10:52:39 +02:00
parent 07a713305a
commit bf66625e02

View file

@ -42,21 +42,23 @@
static void radeon_fence_write(struct radeon_device *rdev, u32 seq, int ring)
{
if (rdev->wb.enabled) {
*rdev->fence_drv[ring].cpu_addr = cpu_to_le32(seq);
struct radeon_fence_driver *drv = &rdev->fence_drv[ring];
if (likely(rdev->wb.enabled || !drv->scratch_reg)) {
*drv->cpu_addr = cpu_to_le32(seq);
} else {
WREG32(rdev->fence_drv[ring].scratch_reg, seq);
WREG32(drv->scratch_reg, seq);
}
}
static u32 radeon_fence_read(struct radeon_device *rdev, int ring)
{
struct radeon_fence_driver *drv = &rdev->fence_drv[ring];
u32 seq = 0;
if (rdev->wb.enabled) {
seq = le32_to_cpu(*rdev->fence_drv[ring].cpu_addr);
if (likely(rdev->wb.enabled || !drv->scratch_reg)) {
seq = le32_to_cpu(*drv->cpu_addr);
} else {
seq = RREG32(rdev->fence_drv[ring].scratch_reg);
seq = RREG32(drv->scratch_reg);
}
return seq;
}