drm/amdgpu: Do not program VM_L2_CNTL under SRIOV

VM_L2_CNTL* should not be programmed on driver unload under SRIOV.
These regs are skipped during SRIOV driver init.
Signed-off-by: Victor Lu <victorchengchi.lu@amd.com>
Reviewed-by: Vignesh Chander <Vignesh.Chander@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfxhub_v1_2.c

@@ -456,10 +456,12 @@ static void gfxhub_v1_2_xcc_gart_disable(struct amdgpu_device *adev,
 		WREG32_SOC15_RLC(GC, GET_INST(GC, j), regMC_VM_MX_L1_TLB_CNTL, tmp);
 
 		/* Setup L2 cache */
-		tmp = RREG32_SOC15(GC, GET_INST(GC, j), regVM_L2_CNTL);
-		tmp = REG_SET_FIELD(tmp, VM_L2_CNTL, ENABLE_L2_CACHE, 0);
-		WREG32_SOC15(GC, GET_INST(GC, j), regVM_L2_CNTL, tmp);
-		WREG32_SOC15(GC, GET_INST(GC, j), regVM_L2_CNTL3, 0);
+		if (!amdgpu_sriov_vf(adev)) {
+			tmp = RREG32_SOC15(GC, GET_INST(GC, j), regVM_L2_CNTL);
+			tmp = REG_SET_FIELD(tmp, VM_L2_CNTL, ENABLE_L2_CACHE, 0);
+			WREG32_SOC15(GC, GET_INST(GC, j), regVM_L2_CNTL, tmp);
+			WREG32_SOC15(GC, GET_INST(GC, j), regVM_L2_CNTL3, 0);
+		}
 	}
 }