drm/amdkfd: Define config HSA_AMD_P2P to support peer-to-peer

Extend current kernel config requirements of amdgpu by adding config
HSA_AMD_P2P. Enabling HSA_AMD_P2P is REQUIRED to support peer-to-peer
communication between AMD GPU devices over PCIe bus

Signed-off-by: Ramesh Errabolu <Ramesh.Errabolu@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdkfd/Kconfig b/drivers/gpu/drm/amd/amdkfd/Kconfig
index 8cc0a76..93bd4ed 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/Kconfig
+++ b/drivers/gpu/drm/amd/amdkfd/Kconfig
@@ -25,3 +25,17 @@ config HSA_AMD_SVM
          preemptions and one based on page faults. To enable page fault
          based memory management on most GFXv9 GPUs, set the module
          parameter amdgpu.noretry=0.
+
+config HSA_AMD_P2P
+       bool "HSA kernel driver support for peer-to-peer for AMD GPU devices"
+       depends on HSA_AMD && PCI_P2PDMA && DMABUF_MOVE_NOTIFY
+       help
+         Enable peer-to-peer (P2P) communication between AMD GPUs over
+         the PCIe bus. This can improve performance of multi-GPU compute
+         applications and libraries by enabling GPUs to access data directly
+         in peer GPUs' memory without intermediate copies in system memory.
+
+         This P2P feature is only enabled on compatible chipsets, and between
+         GPUs with large memory BARs that expose the entire VRAM in PCIe bus
+         address space within the physical address limits of the GPUs.
+