[PATCH 01/10] drm/amdgpu: use only the lower address space on GMC9

[Christian König]

Only use the lower address space on GMC9 for the system domain.
Otherwise we would need to sign extend GMC addresses.

Signed-off-by: Christian König <christian.koenig at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
index e44b5191735d..d982956c8329 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
@@ -938,11 +938,10 @@ static int gmc_v9_0_sw_init(void *handle)
 	if (r)
 		return r;
 
-	/* Set the internal MC address mask
-	 * This is the max address of the GPU's
-	 * internal address space.
+	/* Use only the lower range for the internal MC address mask. This is
+	 * the max address of the GPU's internal address space.
 	 */
-	adev->gmc.mc_mask = 0xffffffffffffULL; /* 48 bit MC */
+	adev->gmc.mc_mask = 0x7fffffffffffULL;
 
 	/* set DMA mask + need_dma32 flags.
 	 * PCIE - can handle 44-bits.
-- 
2.17.1