Cover letter got lost, here it is:

This is in support of a RCCL change that requires specific
coherence behaviour.

Corresponding Thunk patch is at
https://github.com/RadeonOpenCompute/ROCT-Thunk-Interface/pull/88

These flags (for GEM and SVM allocations) allocate
memory that allows for system-scope atomic semantics.

On GFX943 these flags cause caches to be avoided on
non-local memory.

On all other ASICs they are identical in functionality to the
equivalent COHERENT flags.

Signed-off-by: David Francis<[email protected]>
---
  drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c |  2 ++
  drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c           |  1 +
  drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c           |  1 +
  drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c            |  5 ++++-
  drivers/gpu/drm/amd/amdkfd/kfd_svm.c             | 10 +++++++++-
  include/uapi/drm/amdgpu_drm.h                    |  7 +++++++
  include/uapi/linux/kfd_ioctl.h                   |  3 +++
  7 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index 9e18fe5eb190..67634e9f6466 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -1790,6 +1790,8 @@ int amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu(
if (flags & KFD_IOC_ALLOC_MEM_FLAGS_COHERENT)
                alloc_flags |= AMDGPU_GEM_CREATE_COHERENT;
+       if (flags & KFD_IOC_ALLOC_MEM_FLAGS_EXT_COHERENCE)
+               alloc_flags |= AMDGPU_GEM_CREATE_EXT_COHERENCE;
        if (flags & KFD_IOC_ALLOC_MEM_FLAGS_UNCACHED)
                alloc_flags |= AMDGPU_GEM_CREATE_UNCACHED;
diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
index 1c07459e2bd2..6a6f6068bea0 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
@@ -631,6 +631,7 @@ static void gmc_v10_0_get_vm_pte(struct amdgpu_device *adev,
        }
if (bo && bo->flags & (AMDGPU_GEM_CREATE_COHERENT |
+                              AMDGPU_GEM_CREATE_EXT_COHERENCE |
                               AMDGPU_GEM_CREATE_UNCACHED))
                *flags = (*flags & ~AMDGPU_PTE_MTYPE_NV10_MASK) |
                         AMDGPU_PTE_MTYPE_NV10(MTYPE_UC);
diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c 
b/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
index a6ee0220db56..ff330c7c0232 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
@@ -540,6 +540,7 @@ static void gmc_v11_0_get_vm_pte(struct amdgpu_device *adev,
        }
if (bo && bo->flags & (AMDGPU_GEM_CREATE_COHERENT |
+                              AMDGPU_GEM_CREATE_EXT_COHERENCE |
                               AMDGPU_GEM_CREATE_UNCACHED))
                *flags = (*flags & ~AMDGPU_PTE_MTYPE_NV10_MASK) |
                         AMDGPU_PTE_MTYPE_NV10(MTYPE_UC);
diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c 
b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
index 8447fcada8bb..17cf19c868e1 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
@@ -1180,7 +1180,8 @@ static void gmc_v9_0_get_coherence_flags(struct 
amdgpu_device *adev,
  {
        struct amdgpu_device *bo_adev = amdgpu_ttm_adev(bo->tbo.bdev);
        bool is_vram = bo->tbo.resource->mem_type == TTM_PL_VRAM;
-       bool coherent = bo->flags & AMDGPU_GEM_CREATE_COHERENT;
+       bool coherent = bo->flags & (AMDGPU_GEM_CREATE_COHERENT | 
AMDGPU_GEM_CREATE_EXT_COHERENCE);
+       bool ext_coherence = bo->flags & AMDGPU_GEM_CREATE_EXT_COHERENCE;
        bool uncached = bo->flags & AMDGPU_GEM_CREATE_UNCACHED;
        struct amdgpu_vm *vm = mapping->bo_va->base.vm;
        unsigned int mtype_local, mtype;
@@ -1248,6 +1249,8 @@ static void gmc_v9_0_get_coherence_flags(struct 
amdgpu_device *adev,
                snoop = true;
                if (uncached) {
                        mtype = MTYPE_UC;
+               } else if (ext_coherence) {
+                       mtype = is_local ? MTYPE_CC : MTYPE_UC;
                } else if (adev->flags & AMD_IS_APU) {
                        mtype = is_local ? mtype_local : MTYPE_NC;
                } else {
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index 909f1ef8927d..acb87b2fe8df 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -1157,7 +1157,8 @@ svm_range_get_pte_flags(struct kfd_node *node,
        uint32_t mapping_flags = 0;
        uint64_t pte_flags;
        bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
-       bool coherent = flags & KFD_IOCTL_SVM_FLAG_COHERENT;
+       bool coherent = flags & (KFD_IOCTL_SVM_FLAG_COHERENT | 
KFD_IOCTL_SVM_FLAG_EXT_COHERENCE);
+       bool ext_coherence = flags & KFD_IOCTL_SVM_FLAG_EXT_COHERENCE;
        bool uncached = false; /*flags & KFD_IOCTL_SVM_FLAG_UNCACHED;*/
        unsigned int mtype_local;
@@ -1205,6 +1206,13 @@ svm_range_get_pte_flags(struct kfd_node *node,
                snoop = true;
                if (uncached) {
                        mapping_flags |= AMDGPU_VM_MTYPE_UC;
+               } else if (ext_coherence) {
+                       /* local HBM region close to partition */
+                       if (bo_node->adev == node->adev &&
+                           (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == 
node->xcp->mem_id))
+                               mapping_flags |= AMDGPU_VM_MTYPE_CC;
+                       else
+                               mapping_flags |= AMDGPU_VM_MTYPE_UC;
                } else if (domain == SVM_RANGE_VRAM_DOMAIN) {
                        /* local HBM region close to partition */
                        if (bo_node->adev == node->adev &&
diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
index 3b98635bdfa8..7dbee3e3d9d1 100644
--- a/include/uapi/drm/amdgpu_drm.h
+++ b/include/uapi/drm/amdgpu_drm.h
@@ -173,6 +173,13 @@ extern "C" {
   * may override the MTYPE selected in AMDGPU_VA_OP_MAP.
   */
  #define AMDGPU_GEM_CREATE_UNCACHED            (1 << 14)
+/* Flag that BO should be coherent across devices when using device-level
+ * atomics. May depend on GPU instructions to flush caches explicitly.
+ *
+ * This influences the choice of MTYPE in the PTEs on GFXv9 and later GPUs and
+ * may override the MTYPE selected in AMDGPU_VA_OP_MAP.
+ */
+#define AMDGPU_GEM_CREATE_EXT_COHERENCE                (1 << 15)
/* hybrid specific */
  /* Flag that the memory should be in SPARSE resource */
diff --git a/include/uapi/linux/kfd_ioctl.h b/include/uapi/linux/kfd_ioctl.h
index e467ac678ba9..7a4041ee5951 100644
--- a/include/uapi/linux/kfd_ioctl.h
+++ b/include/uapi/linux/kfd_ioctl.h
@@ -416,6 +416,7 @@ struct kfd_ioctl_acquire_vm_args {
  #define KFD_IOC_ALLOC_MEM_FLAGS_AQL_QUEUE_MEM (1 << 27)
  #define KFD_IOC_ALLOC_MEM_FLAGS_COHERENT      (1 << 26)
  #define KFD_IOC_ALLOC_MEM_FLAGS_UNCACHED      (1 << 25)
+#define KFD_IOC_ALLOC_MEM_FLAGS_EXT_COHERENCE  (1 << 24)
/* Allocate memory for later SVM (shared virtual memory) mapping.
   *
@@ -777,6 +778,8 @@ struct kfd_ioctl_cross_memory_copy_deprecated_args {
  #define KFD_IOCTL_SVM_FLAG_GPU_READ_MOSTLY     0x00000020
  /* Keep GPU memory mapping always valid as if XNACK is disable */
  #define KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED   0x00000040
+/* Fine grained coherency between all devices using device-scope atomics */
+#define KFD_IOCTL_SVM_FLAG_EXT_COHERENCE       0x00000080
/**
   * kfd_ioctl_svm_op - SVM ioctl operations
-- 2.34.1

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