From: Alex Deucher alexander.deucher@amd.com
Document the non-VM functions in radeon_gart.c
v2: adjust per Christian's suggestions
Signed-off-by: Alex Deucher alexander.deucher@amd.com --- drivers/gpu/drm/radeon/radeon_gart.c | 125 +++++++++++++++++++++++++++++++++- 1 files changed, 122 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/radeon/radeon_gart.c b/drivers/gpu/drm/radeon/radeon_gart.c index 8c44d1d..f6a9dab 100644 --- a/drivers/gpu/drm/radeon/radeon_gart.c +++ b/drivers/gpu/drm/radeon/radeon_gart.c @@ -31,8 +31,38 @@ #include "radeon_reg.h"
/* + * GART + * The GART (Graphics Aperture Remapping Table) is an aperture + * in the GPU's address space. System pages can be mapped into + * the aperture and look like contiguous pages from the GPU's + * perspective. A page table maps the pages in the aperture + * to the actual backing pages in system memory. + * + * Radeon GPUs support both an internal GART, as described above, + * and AGP. AGP works similarly, but the GART table is configured + * and maintained by the northbridge rather than the driver. + * Radeon hw has a separate AGP aperture that is programmed to + * point to the AGP aperture provided by the northbridge and the + * requests are passed through to the northbridge aperture. + * Both AGP and internal GART can be used at the same time, however + * that is not currently supported by the driver. + * + * This file handles the common internal GART management. + */ + +/* * Common GART table functions. */ +/** + * radeon_gart_table_ram_alloc - allocate system ram for gart page table + * + * @rdev: radeon_device pointer + * + * Allocate system memory for GART page table + * (r1xx-r3xx, non-pcie r4xx, rs400). These asics require the + * gart table to be in system memory. + * Returns 0 for success, -ENOMEM for failure. + */ int radeon_gart_table_ram_alloc(struct radeon_device *rdev) { void *ptr; @@ -54,6 +84,15 @@ int radeon_gart_table_ram_alloc(struct radeon_device *rdev) return 0; }
+/** + * radeon_gart_table_ram_free - free system ram for gart page table + * + * @rdev: radeon_device pointer + * + * Free system memory for GART page table + * (r1xx-r3xx, non-pcie r4xx, rs400). These asics require the + * gart table to be in system memory. + */ void radeon_gart_table_ram_free(struct radeon_device *rdev) { if (rdev->gart.ptr == NULL) { @@ -73,6 +112,16 @@ void radeon_gart_table_ram_free(struct radeon_device *rdev) rdev->gart.table_addr = 0; }
+/** + * radeon_gart_table_vram_alloc - allocate vram for gart page table + * + * @rdev: radeon_device pointer + * + * Allocate video memory for GART page table + * (pcie r4xx, r5xx+). These asics require the + * gart table to be in video memory. + * Returns 0 for success, error for failure. + */ int radeon_gart_table_vram_alloc(struct radeon_device *rdev) { int r; @@ -88,6 +137,16 @@ int radeon_gart_table_vram_alloc(struct radeon_device *rdev) return 0; }
+/** + * radeon_gart_table_vram_pin - pin gart page table in vram + * + * @rdev: radeon_device pointer + * + * Pin the GART page table in vram so it will not be moved + * by the memory manager (pcie r4xx, r5xx+). These asics require the + * gart table to be in video memory. + * Returns 0 for success, error for failure. + */ int radeon_gart_table_vram_pin(struct radeon_device *rdev) { uint64_t gpu_addr; @@ -110,6 +169,14 @@ int radeon_gart_table_vram_pin(struct radeon_device *rdev) return r; }
+/** + * radeon_gart_table_vram_unpin - unpin gart page table in vram + * + * @rdev: radeon_device pointer + * + * Unpin the GART page table in vram (pcie r4xx, r5xx+). + * These asics require the gart table to be in video memory. + */ void radeon_gart_table_vram_unpin(struct radeon_device *rdev) { int r; @@ -126,6 +193,15 @@ void radeon_gart_table_vram_unpin(struct radeon_device *rdev) } }
+/** + * radeon_gart_table_vram_free - free gart page table vram + * + * @rdev: radeon_device pointer + * + * Free the video memory used for the GART page table + * (pcie r4xx, r5xx+). These asics require the gart table to + * be in video memory. + */ void radeon_gart_table_vram_free(struct radeon_device *rdev) { if (rdev->gart.robj == NULL) { @@ -135,12 +211,19 @@ void radeon_gart_table_vram_free(struct radeon_device *rdev) radeon_bo_unref(&rdev->gart.robj); }
- - - /* * Common gart functions. */ +/** + * radeon_gart_unbind - unbind pages from the gart page table + * + * @rdev: radeon_device pointer + * @offset: offset into the GPU's gart aperture + * @pages: number of pages to unbind + * + * Unbinds the requested pages from the gart page table and + * replaces them with the dummy page (all asics). + */ void radeon_gart_unbind(struct radeon_device *rdev, unsigned offset, int pages) { @@ -172,6 +255,19 @@ void radeon_gart_unbind(struct radeon_device *rdev, unsigned offset, radeon_gart_tlb_flush(rdev); }
+/** + * radeon_gart_bind - bind pages into the gart page table + * + * @rdev: radeon_device pointer + * @offset: offset into the GPU's gart aperture + * @pages: number of pages to bind + * @pagelist: pages to bind + * @dma_addr: DMA addresses of pages + * + * Binds the requested pages to the gart page table + * (all asics). + * Returns 0 for success, -EINVAL for failure. + */ int radeon_gart_bind(struct radeon_device *rdev, unsigned offset, int pages, struct page **pagelist, dma_addr_t *dma_addr) { @@ -203,6 +299,14 @@ int radeon_gart_bind(struct radeon_device *rdev, unsigned offset, return 0; }
+/** + * radeon_gart_restore - bind all pages in the gart page table + * + * @rdev: radeon_device pointer + * + * Binds all pages in the gart page table (all asics). + * Used to rebuild the gart table on device startup or resume. + */ void radeon_gart_restore(struct radeon_device *rdev) { int i, j, t; @@ -222,6 +326,14 @@ void radeon_gart_restore(struct radeon_device *rdev) radeon_gart_tlb_flush(rdev); }
+/** + * radeon_gart_init - init the driver info for managing the gart + * + * @rdev: radeon_device pointer + * + * Allocate the dummy page and init the gart driver info (all asics). + * Returns 0 for success, error for failure. + */ int radeon_gart_init(struct radeon_device *rdev) { int r, i; @@ -262,6 +374,13 @@ int radeon_gart_init(struct radeon_device *rdev) return 0; }
+/** + * radeon_gart_fini - tear down the driver info for managing the gart + * + * @rdev: radeon_device pointer + * + * Tear down the gart driver info and free the dummy page (all asics). + */ void radeon_gart_fini(struct radeon_device *rdev) { if (rdev->gart.pages && rdev->gart.pages_addr && rdev->gart.ready) {