From: Graham Sider <[email protected]> By default, set use_mtype_cc_wa to 1 to set PTE coherence flag MTYPE_CC instead of MTYPE_RW by default. This is required for the time being to mitigate a bug causing XCCs to hit stale data due to TCC marking fully dirty lines as exclusive.
Signed-off-by: Graham Sider <[email protected]> Reviewed-by: Joseph Greathouse <[email protected]> Reviewed-by: Felix Kuehling <[email protected]> Signed-off-by: Alex Deucher <[email protected]> --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 + drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 7 +++++++ drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c | 10 +++++++--- drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 7 +++++-- 4 files changed, 20 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index 9904ce78b8fc..a3a0dbeb251f 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -213,6 +213,7 @@ extern int amdgpu_noretry; extern int amdgpu_force_asic_type; extern int amdgpu_smartshift_bias; extern int amdgpu_use_xgmi_p2p; +extern bool amdgpu_use_mtype_cc_wa; #ifdef CONFIG_HSA_AMD extern int sched_policy; extern bool debug_evictions; diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c index e4d09bf0887d..2f38c49aa597 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -831,6 +831,13 @@ MODULE_PARM_DESC(no_queue_eviction_on_vm_fault, "No queue eviction on VM fault ( module_param_named(no_queue_eviction_on_vm_fault, amdgpu_no_queue_eviction_on_vm_fault, int, 0444); #endif +/** + * DOC: use_mtype_cc_wa (bool) + */ +bool amdgpu_use_mtype_cc_wa = true; +MODULE_PARM_DESC(use_mtype_cc_wa, "Use MTYPE_CC workaround (0 = use MTYPE_RW where applicable, 1 = use MTYPE_CC where applicable (default))"); +module_param_named(use_mtype_cc_wa, amdgpu_use_mtype_cc_wa, bool, 0444); + /** * DOC: pcie_p2p (bool) * Enable PCIe P2P (requires large-BAR). Default value: true (on) diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c index d28ffdb07ae6..59ce741dfa73 100644 --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c @@ -1192,6 +1192,7 @@ static void gmc_v9_0_get_coherence_flags(struct amdgpu_device *adev, bool coherent = bo->flags & AMDGPU_GEM_CREATE_COHERENT; bool uncached = bo->flags & AMDGPU_GEM_CREATE_UNCACHED; unsigned int mtype; + unsigned int mtype_default; bool snoop = false; switch (adev->ip_versions[GC_HWIP][0]) { @@ -1235,7 +1236,10 @@ static void gmc_v9_0_get_coherence_flags(struct amdgpu_device *adev, /* FIXME: Needs more work for handling multiple memory * partitions (> NPS1 mode) e.g. NPS4 for both APU and dGPU * modes. + * FIXME: Temporarily using MTYPE_CC instead of MTYPE_RW where applicable. + * To force use of MTYPE_RW, set use_mtype_cc_wa=0 */ + mtype_default = amdgpu_use_mtype_cc_wa ? MTYPE_CC : MTYPE_RW; snoop = true; if (uncached) { mtype = MTYPE_UC; @@ -1250,14 +1254,14 @@ static void gmc_v9_0_get_coherence_flags(struct amdgpu_device *adev, * socket should be treated as remote access so MTYPE_RW * cannot be used always. */ - mtype = MTYPE_RW; + mtype = mtype_default; } else if (adev->flags & AMD_IS_APU) { /* APU on carve out mode */ - mtype = MTYPE_RW; + mtype = mtype_default; } else { /* dGPU */ if (is_vram && bo_adev == adev) - mtype = MTYPE_RW; + mtype = mtype_default; else if (is_vram) mtype = MTYPE_NC; else diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c index 83f8e4e50315..c55b9754c506 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c @@ -1197,9 +1197,12 @@ svm_range_get_pte_flags(struct kfd_node *node, if (uncached) { mapping_flags |= AMDGPU_VM_MTYPE_UC; } else if (domain == SVM_RANGE_VRAM_DOMAIN) { - /* local HBM region close to partition */ + /* local HBM region close to partition + * FIXME: Temporarily using MTYPE_CC instead of MTYPE_RW where applicable. + * To force use of MTYPE_RW, set use_mtype_cc_wa=0 + */ if (bo_node == node) - mapping_flags |= AMDGPU_VM_MTYPE_RW; + mapping_flags |= amdgpu_use_mtype_cc_wa ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW; /* local HBM region far from partition or remote XGMI GPU */ else if (svm_nodes_in_same_hive(bo_node, node)) mapping_flags |= AMDGPU_VM_MTYPE_NC; -- 2.40.1
