drm/radeon: enable pci bus mastering after card is initialised (v2)

This closes a race seen with kexec where we enable PCI bus mastering
but the card has been reinitialised fully yet.

This was previously fixed by a patch from Jerome, but this should
close the race completely.

v2: add SI support as suggested by Alex.

Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index 81801c176aa5..e11df778e194 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -1180,6 +1180,10 @@ int r100_cp_init(struct radeon_device *rdev, unsigned ring_size)
         WREG32(RADEON_CP_RB_WPTR_DELAY, 0);
         WREG32(RADEON_CP_CSQ_MODE, 0x00004D4D);
         WREG32(RADEON_CP_CSQ_CNTL, RADEON_CSQ_PRIBM_INDBM);
+
+        /* at this point everything should be setup correctly to enable master */
+        pci_set_master(rdev->pdev);
+
         radeon_ring_start(rdev, RADEON_RING_TYPE_GFX_INDEX, &rdev->ring[RADEON_RING_TYPE_GFX_INDEX]);
         r = radeon_ring_test(rdev, RADEON_RING_TYPE_GFX_INDEX, ring);
         if (r) {