[PATCH] drm/amdgpu/gmc9: set vram_width properly for SR-IOV

[Alex Deucher]

For SR-IOV, vram_width can't be read from ATOM as
RAVEN, and DF related registers is not readable, so hardcord
is the only way to set the correct vram_width.

Signed-off-by: Trigger Huang <Trigger.Huang at amd.com>
Signed-off-by: Yintian Tao <yttao at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
index 59c580bd5a3b..9750b632e9aa 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
@@ -835,8 +835,16 @@ static int gmc_v9_0_mc_init(struct amdgpu_device *adev)
 	int chansize, numchan;
 	int r;
 
-	if (amdgpu_emu_mode != 1)
+	if (amdgpu_sriov_vf(adev)) {
+		/* For Vega10 SR-IOV, vram_width can't be read from ATOM as RAVEN,
+		 * and DF related registers is not readable, seems hardcord is the
+		 * only way to set the correct vram_width
+		 */
+		adev->gmc.vram_width = 2048;
+	} else if (amdgpu_emu_mode != 1) {
 		adev->gmc.vram_width = amdgpu_atomfirmware_get_vram_width(adev);
+	}
+
 	if (!adev->gmc.vram_width) {
 		/* hbm memory channel size */
 		if (adev->flags & AMD_IS_APU)
-- 
2.20.1