drm/amdgpu: Send no-retry XNACK for all fault types

A subset of VM fault types currently send retry XNACK to the client.
This causes a storm of interrupts from the VM to the host.

Until the storm is throttled by other means send no-retry XNACK for
all fault types instead. No change in behavior to the client which
will stall indefinitely with the current configuration in any case.
Improves system stability under GC or MMHUB faults.

Change-Id: I0eadc91f6fe7e4492f178509742960f06ed0a03f
Signed-off-by: Jay Cornwall <Jay.Cornwall@amd.com>

drivers/gpu/drm/amd/amdgpu/gfxhub_v1_0.c

@@ -223,6 +223,9 @@ int gfxhub_v1_0_gart_enable(struct amdgpu_device *adev)
 		tmp = REG_SET_FIELD(tmp, VM_CONTEXT1_CNTL,
 				PAGE_TABLE_BLOCK_SIZE,
 				    amdgpu_vm_block_size - 9);
+		/* Send no-retry XNACK on fault to suppress VM fault storm. */
+		tmp = REG_SET_FIELD(tmp, VM_CONTEXT1_CNTL,
+				    RETRY_PERMISSION_OR_INVALID_PAGE_FAULT, 0);
 		WREG32(SOC15_REG_OFFSET(GC, 0, mmVM_CONTEXT1_CNTL) + i, tmp);
 		WREG32(SOC15_REG_OFFSET(GC, 0, mmVM_CONTEXT1_PAGE_TABLE_START_ADDR_LO32) + i*2, 0);
 		WREG32(SOC15_REG_OFFSET(GC, 0, mmVM_CONTEXT1_PAGE_TABLE_START_ADDR_HI32) + i*2, 0);

drivers/gpu/drm/amd/amdgpu/mmhub_v1_0.c

@@ -243,6 +243,9 @@ int mmhub_v1_0_gart_enable(struct amdgpu_device *adev)
 		tmp = REG_SET_FIELD(tmp, VM_CONTEXT1_CNTL,
 				PAGE_TABLE_BLOCK_SIZE,
 				amdgpu_vm_block_size - 9);
+		/* Send no-retry XNACK on fault to suppress VM fault storm. */
+		tmp = REG_SET_FIELD(tmp, VM_CONTEXT1_CNTL,
+				    RETRY_PERMISSION_OR_INVALID_PAGE_FAULT, 0);
 		WREG32(SOC15_REG_OFFSET(MMHUB, 0, mmVM_CONTEXT1_CNTL) + i, tmp);
 		WREG32(SOC15_REG_OFFSET(MMHUB, 0, mmVM_CONTEXT1_PAGE_TABLE_START_ADDR_LO32) + i*2, 0);
 		WREG32(SOC15_REG_OFFSET(MMHUB, 0, mmVM_CONTEXT1_PAGE_TABLE_START_ADDR_HI32) + i*2, 0);