SWDEV-363074 - Adjust staging copy limits in Windows

Pinned copy can cause big performance drops, because slow pinning under Windows.
Use up to 128MB for staging transfers. Change staging buffer size to 4MB.
Linux path should still have the old defaults.

Change-Id: I954edceb3ec89e8e670be116aa2d0a9564c8b11c

rocclr/utils/flags.hpp

@@ -66,8 +66,8 @@ release(uint, GPU_CP_DMA_COPY_SIZE, 1,                                        \
         "Set maximum size of CP DMA copy in KiB")                             \
 release(uint, GPU_MAX_HEAP_SIZE, 100,                                         \
         "Set maximum size of the GPU heap to % of board memory")              \
-release(uint, GPU_STAGING_BUFFER_SIZE, 1024,                                  \
-        "Size of the GPU staging buffer in KiB")                              \
+release(uint, GPU_STAGING_BUFFER_SIZE, 4,                                     \
+        "Size of the GPU staging buffer in MiB")                              \
 release(bool, GPU_DUMP_BLIT_KERNELS, false,                                   \
         "Dump the kernels for blit manager")                                  \
 release(uint, GPU_BLIT_ENGINE_TYPE, 0x0,                                      \
@@ -93,9 +93,9 @@ debug(cstring, AMD_OCL_SUBST_OBJFILE, 0,                                      \
 debug(bool, AMD_OCL_ENABLE_MESSAGE_BOX, false,                                \
         "Enable the error dialog on Windows")                                 \
 release(size_t, GPU_PINNED_XFER_SIZE, 32,                                     \
-        "The pinned buffer size for pinning in read/write transfers")         \
-release(size_t, GPU_PINNED_MIN_XFER_SIZE, 1024,                               \
-        "The minimal buffer size for pinned read/write transfers in KBytes")  \
+        "The pinned buffer size for pinning in read/write transfers in MiB")  \
+release(size_t, GPU_PINNED_MIN_XFER_SIZE, 128,                                \
+        "The minimal buffer size for pinned read/write transfers in MiB")     \
 release(size_t, GPU_RESOURCE_CACHE_SIZE, 64,                                  \
         "The resource cache size in MB")                                      \
 release(size_t, GPU_MAX_SUBALLOC_SIZE, 4096,                                  \