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

@@ -456,11 +456,13 @@ 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 */
+		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);
 		}
+	}
 }
 
 static void gfxhub_v1_2_gart_disable(struct amdgpu_device *adev)