From f44ffd677fb3562ac0a1ff9c8ae52672be741f00 Mon Sep 17 00:00:00 2001 From: Christian König Date: Fri, 23 Mar 2018 16:56:37 +0100 Subject: drm/amdgpu: add support for exporting VRAM using DMA-buf v3 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We should be able to do this now after checking all the prerequisites. v2: fix entrie count in the sgt v3: manually construct the sg Signed-off-by: Christian König Acked-by: Daniel Vetter Acked-by: Sumit Semwal Link: https://patchwork.freedesktop.org/patch/359295 --- drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 99 ++++++++++++++++++++++++++++ 1 file changed, 99 insertions(+) (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c') diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c index 82a3299e53c0..128a667ed8fa 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c @@ -22,6 +22,7 @@ * Authors: Christian König */ +#include #include "amdgpu.h" #include "amdgpu_vm.h" #include "amdgpu_atomfirmware.h" @@ -458,6 +459,104 @@ static void amdgpu_vram_mgr_del(struct ttm_mem_type_manager *man, mem->mm_node = NULL; } +/** + * amdgpu_vram_mgr_alloc_sgt - allocate and fill a sg table + * + * @adev: amdgpu device pointer + * @mem: TTM memory object + * @dev: the other device + * @dir: dma direction + * @sgt: resulting sg table + * + * Allocate and fill a sg table from a VRAM allocation. + */ +int amdgpu_vram_mgr_alloc_sgt(struct amdgpu_device *adev, + struct ttm_mem_reg *mem, + struct device *dev, + enum dma_data_direction dir, + struct sg_table **sgt) +{ + struct drm_mm_node *node; + struct scatterlist *sg; + int num_entries = 0; + unsigned int pages; + int i, r; + + *sgt = kmalloc(sizeof(*sg), GFP_KERNEL); + if (!*sgt) + return -ENOMEM; + + for (pages = mem->num_pages, node = mem->mm_node; + pages; pages -= node->size, ++node) + ++num_entries; + + r = sg_alloc_table(*sgt, num_entries, GFP_KERNEL); + if (r) + goto error_free; + + for_each_sg((*sgt)->sgl, sg, num_entries, i) + sg->length = 0; + + node = mem->mm_node; + for_each_sg((*sgt)->sgl, sg, num_entries, i) { + phys_addr_t phys = (node->start << PAGE_SHIFT) + + adev->gmc.aper_base; + size_t size = node->size << PAGE_SHIFT; + dma_addr_t addr; + + ++node; + addr = dma_map_resource(dev, phys, size, dir, + DMA_ATTR_SKIP_CPU_SYNC); + r = dma_mapping_error(dev, addr); + if (r) + goto error_unmap; + + sg_set_page(sg, NULL, size, 0); + sg_dma_address(sg) = addr; + sg_dma_len(sg) = size; + } + return 0; + +error_unmap: + for_each_sg((*sgt)->sgl, sg, num_entries, i) { + if (!sg->length) + continue; + + dma_unmap_resource(dev, sg->dma_address, + sg->length, dir, + DMA_ATTR_SKIP_CPU_SYNC); + } + sg_free_table(*sgt); + +error_free: + kfree(*sgt); + return r; +} + +/** + * amdgpu_vram_mgr_alloc_sgt - allocate and fill a sg table + * + * @adev: amdgpu device pointer + * @sgt: sg table to free + * + * Free a previously allocate sg table. + */ +void amdgpu_vram_mgr_free_sgt(struct amdgpu_device *adev, + struct device *dev, + enum dma_data_direction dir, + struct sg_table *sgt) +{ + struct scatterlist *sg; + int i; + + for_each_sg(sgt->sgl, sg, sgt->nents, i) + dma_unmap_resource(dev, sg->dma_address, + sg->length, dir, + DMA_ATTR_SKIP_CPU_SYNC); + sg_free_table(sgt); + kfree(sgt); +} + /** * amdgpu_vram_mgr_usage - how many bytes are used in this domain * -- cgit