drm/radeon/kms: set DMA mask properly on newer PCI asics

If a card wasn't PCIE, we always set the DMA mask to 32 bits.
This is only applies to the old rage128/r1xx gart block on
early radeon asics (~r1xx-r4xx).  Newer PCI and IGP cards
can handle 40 bits just fine.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Chen Jie <chenj@lemote.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 31b1f4bf133e..cc695d05bd2b 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -750,14 +750,15 @@ int radeon_device_init(struct radeon_device *rdev,
 
         /* set DMA mask + need_dma32 flags.
          * PCIE - can handle 40-bits.
-         * IGP - can handle 40-bits (in theory)
+         * IGP - can handle 40-bits
          * AGP - generally dma32 is safest
-         * PCI - only dma32
+         * PCI - dma32 for legacy pci gart, 40 bits on newer asics
          */
         rdev->need_dma32 = false;
         if (rdev->flags & RADEON_IS_AGP)
                 rdev->need_dma32 = true;
-        if (rdev->flags & RADEON_IS_PCI)
+        if ((rdev->flags & RADEON_IS_PCI) &&
+            (rdev->family < CHIP_RS400))
                 rdev->need_dma32 = true;
 
         dma_bits = rdev->need_dma32 ? 32 : 40;