[PATCH 14/14] drm/amdkfd: mark GFX12 system and peer GPU memory mappings as MTYPE_NC

[Alex Deucher]

From: Sreekant Somasekharan <sreekant.somasekha...@amd.com>

Due to a HW bug, the system memory mappings and peer GPU mappings
on GFX12 need to be marked as MTYPE_NC.

Cc: Joe Greathouse <joseph.greatho...@amd.com>
Cc: David Belanger <david.belan...@amd.com>
Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhard...@amd.com>
Signed-off-by: Sreekant Somasekharan <sreekant.somasekha...@amd.com>
Reviewed-by: Harish Kasiviswanathan <harish.kasiviswanat...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c | 9 +++++++++
 drivers/gpu/drm/amd/amdkfd/kfd_svm.c   | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c 
b/drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c
index c24f5bd3e09ce..3e6676fdc1875 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c
@@ -497,6 +497,10 @@ static void gmc_v12_0_get_vm_pte(struct amdgpu_device 
*adev,
                                 uint64_t *flags)
 {
        struct amdgpu_bo *bo = mapping->bo_va->base.bo;
+       struct amdgpu_device *bo_adev = amdgpu_ttm_adev(bo->tbo.bdev);
+       bool coherent = bo->flags & AMDGPU_GEM_CREATE_COHERENT;
+       bool is_system = bo->tbo.resource->mem_type == TTM_PL_SYSTEM;
+
 
        *flags &= ~AMDGPU_PTE_EXECUTABLE;
        *flags |= mapping->flags & AMDGPU_PTE_EXECUTABLE;
@@ -515,6 +519,11 @@ static void gmc_v12_0_get_vm_pte(struct amdgpu_device 
*adev,
                               AMDGPU_GEM_CREATE_UNCACHED))
                *flags = (*flags & ~AMDGPU_PTE_MTYPE_GFX12_MASK) |
                         AMDGPU_PTE_MTYPE_GFX12(MTYPE_UC);
+
+       /* WA for HW bug */
+       if ((bo && is_system) || ((bo_adev != adev) && coherent))
+               *flags |= AMDGPU_PTE_MTYPE_GFX12(MTYPE_NC);
+
 }
 
 static unsigned gmc_v12_0_get_vbios_fb_size(struct amdgpu_device *adev)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index fc5ede17f7c22..db90795e6245a 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -1248,6 +1248,15 @@ svm_range_get_pte_flags(struct kfd_node *node,
                        mapping_flags |= AMDGPU_VM_MTYPE_UC;
                }
                break;
+       case IP_VERSION(12, 0, 0):
+               if (domain == SVM_RANGE_VRAM_DOMAIN) {
+                       if (bo_node != node)
+                               mapping_flags |= AMDGPU_VM_MTYPE_NC;
+               } else {
+                       mapping_flags |= coherent ?
+                               AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
+               }
+               break;
        default:
                mapping_flags |= coherent ?
                        AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
-- 
2.44.0