[PATCH AUTOSEL 5.10 069/217] drm/amd/amdgpu: Add rev_id workaround logic for SRIOV setup

Sasha Levin
2020-12-23T03:08:05Z

From: Bokun Zhang <Bokun.Zhang@amd.com>

[ Upstream commit de21e4aeb2b26128dcc5be1bcb2fafa73d041e51 ]

- When we are under SRIOV setup, the rev_id cannot be read
properly. Therefore, we will return default value for it

Signed-off-by: Bokun Zhang <Bokun.Zhang@amd.com>
Reviewed-by: Monk Liu <monk.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/amd/amdgpu/nbio_v2_3.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/nbio_v2_3.c b/drivers/gpu/drm/amd/amdgpu/nbio_v2_3.c
index 7429f30398b9d..cd822ea78ffbc 100644
--- a/drivers/gpu/drm/amd/amdgpu/nbio_v2_3.c
+++ b/drivers/gpu/drm/amd/amdgpu/nbio_v2_3.c
@@ -51,8 +51,17 @@ static void nbio_v2_3_remap_hdp_registers(struct amdgpu_device *adev)

static u32 nbio_v2_3_get_rev_id(struct amdgpu_device *adev)
{
- u32 tmp = RREG32_SOC15(NBIO, 0, mmRCC_DEV0_EPF0_STRAP0);
+ u32 tmp;

+ /*
+ * guest vm gets 0xffffffff when reading RCC_DEV0_EPF0_STRAP0,
+ * therefore we force rev_id to 0 (which is the default value)
+ */
+ if (amdgpu_sriov_vf(adev)) {
+ return 0;
+ }
+
+ tmp = RREG32_SOC15(NBIO, 0, mmRCC_DEV0_EPF0_STRAP0);
tmp &= RCC_DEV0_EPF0_STRAP0__STRAP_ATI_REV_ID_DEV0_F0_MASK;
tmp >>= RCC_DEV0_EPF0_STRAP0__STRAP_ATI_REV_ID_DEV0_F0__SHIFT;

--
2.27.0