From 8c2ca9c7f99f3f502756326517010ef5f375ed47 Mon Sep 17 00:00:00 2001
From: Ramesh Errabolu <Ramesh.Errabolu@amd.com>
Date: Thu, 26 May 2022 11:51:08 -0500
Subject: drm/amdkfd: Define config HSA_AMD_P2P to support peer-to-peer
Git-commit: 6fbfc3a23c98bdcda679161c4f4e31368008af8a
Patch-mainline: v6.0-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225 jsc#PED-2849

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>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/amdkfd/Kconfig | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdkfd/Kconfig b/drivers/gpu/drm/amd/amdkfd/Kconfig
index 8cc0a76ddf9f..93bd4eda0d94 100644
--- 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.
+
-- 
2.38.1