gpu: nvgpu: RDMA implementation

This change adds RDMA supports for tegra iGPU.
1. Cuda Process allocates the memory and passes
   the VA and size to the custom kernel driver.
2. The custom kernel driver maps the user allocated
   buf and does the DMA to/from it.
3. Only supports iGPU + cudaHostAlloc sysmem
4. Works only for a given process.
5. Address should be sysmem page aligned and size should
   be multiple of sysmem page size.
6. The custom kernel driver must register a free_callback when get_page()
   function is called.

Bug 200438879

Signed-off-by: Preetham Chandru R <pchandru@nvidia.com>
Change-Id: I43ec45734eb46d30341d0701550206c16e051106
Reviewed-on: https://git-master.nvidia.com/r/1953780
GVS: Gerrit_Virtual_Submit
Reviewed-by: Alex Waterman <alexw@nvidia.com>
Reviewed-by: Bibek Basu <bbasu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/Makefile b/drivers/gpu/nvgpu/Makefile
index e0fd70e6..fdfaf092 100644
--- a/drivers/gpu/nvgpu/Makefile
+++ b/drivers/gpu/nvgpu/Makefile
@@ -176,6 +176,9 @@ nvgpu-$(CONFIG_NVGPU_SUPPORT_CDE) += \
         os/linux/cde_gm20b.o \
         os/linux/cde_gp10b.o
 
+nvgpu-$(CONFIG_GK20A_RDMA) += \
+        os/linux/nvidia_p2p.o
+
 ifeq ($(CONFIG_DEBUG_FS),y)
 nvgpu-$(CONFIG_NVGPU_SUPPORT_CDE) += \
         os/linux/debug_cde.o