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drm/amdgpu: Remove writing GRBM_GFX_CNTL in RLCG interface under SRIOV

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[Why]
Accessing GRBM_GFX_CNTL in full access time has risk when VF is doing MMIO attacking.
Therefore, VF writing GRBM_GFX_CNTL are blocked by L1 Policy.
For RLCG interface, RLCG use SCRATCH_REG2 which is copied from GRBM_GFX_CNTL.

[How]
Remove writing GRBM_GFX_CNTL in amdgpu_virt_rlcg_reg_rw.

v2:
Remove directly writing GRBM_GFX_INDEX in amdgpu_virt_rlcg_reg_rw
as RLCG interface no need to use it.

Signed-off-by: Yifan Zha <Yifan.Zha@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Yifan Zha 2023-01-31 15:31:27 +08:00 committed by Alex Deucher
parent 11cc4652e9
commit 72fef4980d
1 changed files with 0 additions and 2 deletions
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2
drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
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@ -983,11 +983,9 @@ static u32 amdgpu_virt_rlcg_reg_rw(struct amdgpu_device *adev, u32 offset, u32 v
if (offset == reg_access_ctrl->grbm_cntl) {
/* if the target reg offset is grbm_cntl, write to scratch_reg2 */
writel(v, scratch_reg2);
writel(v, ((void __iomem *)adev->rmmio) + (offset * 4));
} else if (offset == reg_access_ctrl->grbm_idx) {
/* if the target reg offset is grbm_idx, write to scratch_reg3 */
writel(v, scratch_reg3);
writel(v, ((void __iomem *)adev->rmmio) + (offset * 4));
} else {
/*
* SCRATCH_REG0 = read/write value