drm/radeon/kms: set gart pages to invalid on unbind and point to dummy page

this uses a new entrypoint to invalidate gart entries instead of using 0.
Changed to rather than pointing to 0 address point empty entry to dummy
page. This might help to avoid hard lockup if for some wrong
reasons GPU try to access unmapped GART entry.

I'm not 100% sure this is going to work, we probably need to allocate
a dummy page and point all the GTT entries at it similiar to what AGP does.
but we can test this first I suppose.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index 346ae3d7e0d4..bc7d9e9211c8 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -197,6 +197,7 @@ int r100_pci_gart_enable(struct radeon_device *rdev)
 {
         uint32_t tmp;
 
+        radeon_gart_restore(rdev);
         /* discard memory request outside of configured range */
         tmp = RREG32(RADEON_AIC_CNTL) | RADEON_DIS_OUT_OF_PCI_GART_ACCESS;
         WREG32(RADEON_AIC_CNTL, tmp);