Commit 237d623a authored by Timur Kristóf's avatar Timur Kristóf Committed by Alex Deucher
Browse files

drm/amdgpu/gart: Add helper to bind VRAM pages (v2) 



Binds pages that located in VRAM to the GART page table.

Useful when a kernel BO is located in VRAM but
needs to be accessed from the GART address space,
for example to give a kernel BO a 32-bit address
when GART is placed in LOW address space.

v2:
- Refactor function to be more reusable

Signed-off-by: default avatarTimur Kristóf <timur.kristof@gmail.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 3a4132e6

drivers/gpu/drm/amd/amdgpu/amdgpu_gart.c

+36 −0
Original line number Diff line number Diff line
@@ -367,6 +367,42 @@ void amdgpu_gart_map(struct amdgpu_device *adev, uint64_t offset, 
	drm_dev_exit(idx);

}



/**

 * amdgpu_gart_map_vram_range - map VRAM pages into the GART page table

 *

 * @adev: amdgpu_device pointer

 * @pa: physical address of the first page to be mapped

 * @start_page: first page to map in the GART aperture

 * @num_pages: number of pages to be mapped

 * @flags: page table entry flags

 * @dst: CPU address of the GART table

 *

 * Binds a BO that is allocated in VRAM to the GART page table

 * (all ASICs).

 *

 * Useful when a kernel BO is located in VRAM but

 * needs to be accessed from the GART address space.

 */

void amdgpu_gart_map_vram_range(struct amdgpu_device *adev, uint64_t pa,

				uint64_t start_page, uint64_t num_pages,

				uint64_t flags, void *dst)

{

	u32 i, idx;



	/* The SYSTEM flag indicates the pages aren't in VRAM. */

	WARN_ON_ONCE(flags & AMDGPU_PTE_SYSTEM);



	if (!drm_dev_enter(adev_to_drm(adev), &idx))

		return;



	for (i = 0; i < num_pages; ++i) {

		amdgpu_gmc_set_pte_pde(adev, adev->gart.ptr,

			start_page + i, pa + AMDGPU_GPU_PAGE_SIZE * i, flags);

	}



	drm_dev_exit(idx);

}



/**

 * amdgpu_gart_bind - bind pages into the gart page table

 *

drivers/gpu/drm/amd/amdgpu/amdgpu_gart.h

+3 −0
Original line number Diff line number Diff line
@@ -64,5 +64,8 @@ void amdgpu_gart_map(struct amdgpu_device *adev, uint64_t offset, 
		     void *dst);

void amdgpu_gart_bind(struct amdgpu_device *adev, uint64_t offset,

		      int pages, dma_addr_t *dma_addr, uint64_t flags);

void amdgpu_gart_map_vram_range(struct amdgpu_device *adev, uint64_t pa,

				uint64_t start_page, uint64_t num_pages,

				uint64_t flags, void *dst);

void amdgpu_gart_invalidate_tlb(struct amdgpu_device *adev);

#endif