Rob Clark | 6ad11bc | 2012-04-10 13:19:55 -0500 | [diff] [blame^] | 1 | /* |
| 2 | * drivers/staging/omapdrm/omap_gem_dmabuf.c |
| 3 | * |
| 4 | * Copyright (C) 2011 Texas Instruments |
| 5 | * Author: Rob Clark <rob.clark@linaro.org> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify it |
| 8 | * under the terms of the GNU General Public License version 2 as published by |
| 9 | * the Free Software Foundation. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 14 | * more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License along with |
| 17 | * this program. If not, see <http://www.gnu.org/licenses/>. |
| 18 | */ |
| 19 | |
| 20 | #include "omap_drv.h" |
| 21 | |
| 22 | #include <linux/dma-buf.h> |
| 23 | |
| 24 | static struct sg_table *omap_gem_map_dma_buf( |
| 25 | struct dma_buf_attachment *attachment, |
| 26 | enum dma_data_direction dir) |
| 27 | { |
| 28 | struct drm_gem_object *obj = attachment->dmabuf->priv; |
| 29 | struct sg_table *sg; |
| 30 | dma_addr_t paddr; |
| 31 | int ret; |
| 32 | |
| 33 | sg = kzalloc(sizeof(*sg), GFP_KERNEL); |
| 34 | if (!sg) |
| 35 | return ERR_PTR(-ENOMEM); |
| 36 | |
| 37 | /* camera, etc, need physically contiguous.. but we need a |
| 38 | * better way to know this.. |
| 39 | */ |
| 40 | ret = omap_gem_get_paddr(obj, &paddr, true); |
| 41 | if (ret) |
| 42 | goto out; |
| 43 | |
| 44 | ret = sg_alloc_table(sg, 1, GFP_KERNEL); |
| 45 | if (ret) |
| 46 | goto out; |
| 47 | |
| 48 | sg_init_table(sg->sgl, 1); |
| 49 | sg_dma_len(sg->sgl) = obj->size; |
| 50 | sg_set_page(sg->sgl, pfn_to_page(PFN_DOWN(paddr)), obj->size, 0); |
| 51 | sg_dma_address(sg->sgl) = paddr; |
| 52 | |
| 53 | out: |
| 54 | if (ret) |
| 55 | return ERR_PTR(ret); |
| 56 | return sg; |
| 57 | } |
| 58 | |
| 59 | static void omap_gem_unmap_dma_buf(struct dma_buf_attachment *attachment, |
| 60 | struct sg_table *sg, enum dma_data_direction dir) |
| 61 | { |
| 62 | struct drm_gem_object *obj = attachment->dmabuf->priv; |
| 63 | omap_gem_put_paddr(obj); |
| 64 | sg_free_table(sg); |
| 65 | kfree(sg); |
| 66 | } |
| 67 | |
| 68 | static void omap_gem_dmabuf_release(struct dma_buf *buffer) |
| 69 | { |
| 70 | struct drm_gem_object *obj = buffer->priv; |
| 71 | /* release reference that was taken when dmabuf was exported |
| 72 | * in omap_gem_prime_set().. |
| 73 | */ |
| 74 | drm_gem_object_unreference_unlocked(obj); |
| 75 | } |
| 76 | |
| 77 | |
| 78 | static int omap_gem_dmabuf_begin_cpu_access(struct dma_buf *buffer, |
| 79 | size_t start, size_t len, enum dma_data_direction dir) |
| 80 | { |
| 81 | struct drm_gem_object *obj = buffer->priv; |
| 82 | struct page **pages; |
| 83 | if (omap_gem_flags(obj) & OMAP_BO_TILED) { |
| 84 | /* TODO we would need to pin at least part of the buffer to |
| 85 | * get de-tiled view. For now just reject it. |
| 86 | */ |
| 87 | return -ENOMEM; |
| 88 | } |
| 89 | /* make sure we have the pages: */ |
| 90 | return omap_gem_get_pages(obj, &pages, true); |
| 91 | } |
| 92 | |
| 93 | static void omap_gem_dmabuf_end_cpu_access(struct dma_buf *buffer, |
| 94 | size_t start, size_t len, enum dma_data_direction dir) |
| 95 | { |
| 96 | struct drm_gem_object *obj = buffer->priv; |
| 97 | omap_gem_put_pages(obj); |
| 98 | } |
| 99 | |
| 100 | |
| 101 | static void *omap_gem_dmabuf_kmap_atomic(struct dma_buf *buffer, |
| 102 | unsigned long page_num) |
| 103 | { |
| 104 | struct drm_gem_object *obj = buffer->priv; |
| 105 | struct page **pages; |
| 106 | omap_gem_get_pages(obj, &pages, false); |
| 107 | return kmap_atomic(pages[page_num]); |
| 108 | } |
| 109 | |
| 110 | static void omap_gem_dmabuf_kunmap_atomic(struct dma_buf *buffer, |
| 111 | unsigned long page_num, void *addr) |
| 112 | { |
| 113 | kunmap_atomic(addr); |
| 114 | } |
| 115 | |
| 116 | static void *omap_gem_dmabuf_kmap(struct dma_buf *buffer, |
| 117 | unsigned long page_num) |
| 118 | { |
| 119 | struct drm_gem_object *obj = buffer->priv; |
| 120 | struct page **pages; |
| 121 | omap_gem_get_pages(obj, &pages, false); |
| 122 | return kmap(pages[page_num]); |
| 123 | } |
| 124 | |
| 125 | static void omap_gem_dmabuf_kunmap(struct dma_buf *buffer, |
| 126 | unsigned long page_num, void *addr) |
| 127 | { |
| 128 | struct drm_gem_object *obj = buffer->priv; |
| 129 | struct page **pages; |
| 130 | omap_gem_get_pages(obj, &pages, false); |
| 131 | kunmap(pages[page_num]); |
| 132 | } |
| 133 | |
| 134 | struct dma_buf_ops omap_dmabuf_ops = { |
| 135 | .map_dma_buf = omap_gem_map_dma_buf, |
| 136 | .unmap_dma_buf = omap_gem_unmap_dma_buf, |
| 137 | .release = omap_gem_dmabuf_release, |
| 138 | .begin_cpu_access = omap_gem_dmabuf_begin_cpu_access, |
| 139 | .end_cpu_access = omap_gem_dmabuf_end_cpu_access, |
| 140 | .kmap_atomic = omap_gem_dmabuf_kmap_atomic, |
| 141 | .kunmap_atomic = omap_gem_dmabuf_kunmap_atomic, |
| 142 | .kmap = omap_gem_dmabuf_kmap, |
| 143 | .kunmap = omap_gem_dmabuf_kunmap, |
| 144 | }; |
| 145 | |
| 146 | struct dma_buf * omap_gem_prime_export(struct drm_device *dev, |
| 147 | struct drm_gem_object *obj, int flags) |
| 148 | { |
| 149 | return dma_buf_export(obj, &omap_dmabuf_ops, obj->size, 0600); |
| 150 | } |