[PATCH 05/12] drm/amdgpu: Send no-retry XNACK for all fault types

[Felix Kuehling]

From: Jay Cornwall <Jay.Cornwall at amd.com>

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.

Signed-off-by: Jay Cornwall <Jay.Cornwall at amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gfxhub_v1_0.c | 3 +++
 drivers/gpu/drm/amd/amdgpu/mmhub_v1_0.c  | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/gfxhub_v1_0.c b/drivers/gpu/drm/amd/amdgpu/gfxhub_v1_0.c
index a42f483..f957b18 100644
--- a/drivers/gpu/drm/amd/amdgpu/gfxhub_v1_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfxhub_v1_0.c
@@ -206,6 +206,9 @@ static void gfxhub_v1_0_setup_vmid_config(struct amdgpu_device *adev)
 		tmp = REG_SET_FIELD(tmp, VM_CONTEXT1_CNTL,
 				PAGE_TABLE_BLOCK_SIZE,
 				adev->vm_manager.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_OFFSET(GC, 0, mmVM_CONTEXT1_CNTL, i, tmp);
 		WREG32_SOC15_OFFSET(GC, 0, mmVM_CONTEXT1_PAGE_TABLE_START_ADDR_LO32, i*2, 0);
 		WREG32_SOC15_OFFSET(GC, 0, mmVM_CONTEXT1_PAGE_TABLE_START_ADDR_HI32, i*2, 0);
diff --git a/drivers/gpu/drm/amd/amdgpu/mmhub_v1_0.c b/drivers/gpu/drm/amd/amdgpu/mmhub_v1_0.c
index 01918dc..b760018 100644
--- a/drivers/gpu/drm/amd/amdgpu/mmhub_v1_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/mmhub_v1_0.c
@@ -222,6 +222,9 @@ static void mmhub_v1_0_setup_vmid_config(struct amdgpu_device *adev)
 		tmp = REG_SET_FIELD(tmp, VM_CONTEXT1_CNTL,
 				PAGE_TABLE_BLOCK_SIZE,
 				adev->vm_manager.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_OFFSET(MMHUB, 0, mmVM_CONTEXT1_CNTL, i, tmp);
 		WREG32_SOC15_OFFSET(MMHUB, 0, mmVM_CONTEXT1_PAGE_TABLE_START_ADDR_LO32, i*2, 0);
 		WREG32_SOC15_OFFSET(MMHUB, 0, mmVM_CONTEXT1_PAGE_TABLE_START_ADDR_HI32, i*2, 0);
-- 
1.9.1