From c03048d68ef97f1309c04f377ad9b6e6f9b452e6 Mon Sep 17 00:00:00 2001
From: Jimbo <57198431+jiabaxie@users.noreply.github.com>
Date: Tue, 26 Aug 2025 11:34:49 -0400
Subject: [PATCH] Implement hipMemAllocationTypeUncached in hipMemCreate (#747)

* Revert "SWDEV-547589 - Add hipDeviceMallocUncached to hipMemCreate (#815)"

This reverts commit 5ce7103555c8483e04d84ad314fb86dd98b7afdc.

* Revert "SWDEV-547589 - comment for flag hipDeviceMallocUncached in hipMemcreate (#339)"

This reverts commit 04dac5eae38c8a86aa59fa1c7530233e1a01327c.

* SWDEV-551942 - implement hipMemAllocationTypeUncached in hipMemCreate
---
 projects/clr/CHANGELOG.md                  |  4 +++-
 projects/clr/hipamd/src/hip_vm.cpp         | 24 ++++++++++------------
 projects/hip/include/hip/hip_runtime_api.h |  3 ++-
 3 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/projects/clr/CHANGELOG.md b/projects/clr/CHANGELOG.md
index 8549873d1b..101ac50e84 100644
--- a/projects/clr/CHANGELOG.md
+++ b/projects/clr/CHANGELOG.md
@@ -27,7 +27,9 @@ Full documentation for HIP is available at [rocm.docs.amd.com](https://rocm.docs
     - `hipMemAdvise_v2`         advise about the usage of a given memory range
     - `hipGetDriverEntryPoint ` gets function pointer of a HIP API.
 * Changed HIP APIs
-    - `hipMemCreate`  now can take hipDeviceMallocUncached as a flag to allocate uncached memory
+    - `hipMemAllocationType` now has hip exclusive enum hipMemAllocationTypeUncached
+    - `hipMemCreate`  now checks for hipMemAllocationTypeUncached enum from
+      hipMemAllocationType and allocates uncached memory if so
 
 ### Optimized
 
diff --git a/projects/clr/hipamd/src/hip_vm.cpp b/projects/clr/hipamd/src/hip_vm.cpp
index 1ef80a72bc..37dbc8a219 100644
--- a/projects/clr/hipamd/src/hip_vm.cpp
+++ b/projects/clr/hipamd/src/hip_vm.cpp
@@ -85,12 +85,9 @@ hipError_t hipMemCreate(hipMemGenericAllocationHandle_t* handle, size_t size,
   HIP_INIT_API(hipMemCreate, handle, size, prop, flags);
 
   //  Currently we do not support Pinned memory
-  if (handle == nullptr || size == 0 || prop == nullptr ||
-      prop->type != hipMemAllocationTypePinned || prop->location.type != hipMemLocationTypeDevice) {
-    HIP_RETURN(hipErrorInvalidValue);
-  }
-
-  if (flags != hipDeviceMallocUncached && flags != 0) {
+  if (handle == nullptr || size == 0 || flags != 0 || prop == nullptr ||
+      (prop->type != hipMemAllocationTypePinned && prop->type != hipMemAllocationTypeUncached) ||
+      prop->location.type != hipMemLocationTypeDevice) {
     HIP_RETURN(hipErrorInvalidValue);
   }
 
@@ -103,6 +100,12 @@ hipError_t hipMemCreate(hipMemGenericAllocationHandle_t* handle, size_t size,
     HIP_RETURN(hipErrorNotSupported);
   }
 
+  // When ROCCLR_MEM_PHYMEM is set, ROCr impl gets and stores unique hsa handle. Flag no-op on PAL.
+  unsigned int ihipFlags = ROCCLR_MEM_PHYMEM;
+  if (prop->type == hipMemAllocationTypeUncached) {
+    ihipFlags |= CL_MEM_SVM_ATOMICS | ROCCLR_MEM_HSA_UNCACHED;
+  }
+
   // Device info validation
   const auto& dev_info = g_devices[prop->location.id]->devices()[0]->info();
 
@@ -115,13 +118,8 @@ hipError_t hipMemCreate(hipMemGenericAllocationHandle_t* handle, size_t size,
 
   amd::Context* amdContext = g_devices[prop->location.id]->asContext();
 
-  // When ROCCLR_MEM_PHYMEM is set, ROCr impl gets and stores unique hsa handle. Flag no-op on PAL.
-  uint64_t ihipFlags = ROCCLR_MEM_PHYMEM;
-  if (flags == hipDeviceMallocUncached) {
-    ihipFlags |= ROCCLR_MEM_HSA_UNCACHED | CL_MEM_SVM_ATOMICS;
-  }
-  void* ptr =
-      amd::SvmBuffer::malloc(*amdContext, ihipFlags, size, dev_info.memBaseAddrAlign_, nullptr);
+  void* ptr = amd::SvmBuffer::malloc(*amdContext, ihipFlags, size,
+                                     dev_info.memBaseAddrAlign_, nullptr);
 
   // Handle out of memory cases,
   if (ptr == nullptr) {
diff --git a/projects/hip/include/hip/hip_runtime_api.h b/projects/hip/include/hip/hip_runtime_api.h
index 381f5ea923..b3b8889d1f 100644
--- a/projects/hip/include/hip/hip_runtime_api.h
+++ b/projects/hip/include/hip/hip_runtime_api.h
@@ -1194,6 +1194,7 @@ typedef enum hipMemAllocationType {
    * location while the application is actively using it
    */
   hipMemAllocationTypePinned = 0x1,
+  hipMemAllocationTypeUncached = 0x40000000,
   hipMemAllocationTypeMax = 0x7FFFFFFF
 } hipMemAllocationType;
 /**
@@ -9137,7 +9138,7 @@ hipError_t hipMemAddressReserve(void** ptr, size_t size, size_t alignment, void*
  * @param [out] handle - value of the returned handle.
  * @param [in] size - size of the allocation.
  * @param [in] prop - properties of the allocation.
- * @param [in] flags - hipDeviceMallocUncached for uncached allocation, or 0 for default
+ * @param [in] flags - currently unused, must be zero.
  * @returns #hipSuccess, #hipErrorInvalidValue, #hipErrorNotSupported
  * @warning This API is marked as Beta. While this feature is complete, it can
  *          change and might have outstanding issues.