1 /* 2 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/ 3 * Author: Rob Clark <rob.clark@linaro.org> 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 as published by 7 * the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along with 15 * this program. If not, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #include <linux/dma-buf.h> 19 20 #include "omap_drv.h" 21 22 /* ----------------------------------------------------------------------------- 23 * DMABUF Export 24 */ 25 26 static struct sg_table *omap_gem_map_dma_buf( 27 struct dma_buf_attachment *attachment, 28 enum dma_data_direction dir) 29 { 30 struct drm_gem_object *obj = attachment->dmabuf->priv; 31 struct sg_table *sg; 32 dma_addr_t dma_addr; 33 int ret; 34 35 sg = kzalloc(sizeof(*sg), GFP_KERNEL); 36 if (!sg) 37 return ERR_PTR(-ENOMEM); 38 39 /* camera, etc, need physically contiguous.. but we need a 40 * better way to know this.. 41 */ 42 ret = omap_gem_pin(obj, &dma_addr); 43 if (ret) 44 goto out; 45 46 ret = sg_alloc_table(sg, 1, GFP_KERNEL); 47 if (ret) 48 goto out; 49 50 sg_init_table(sg->sgl, 1); 51 sg_dma_len(sg->sgl) = obj->size; 52 sg_set_page(sg->sgl, pfn_to_page(PFN_DOWN(dma_addr)), obj->size, 0); 53 sg_dma_address(sg->sgl) = dma_addr; 54 55 /* this must be after omap_gem_pin() to ensure we have pages attached */ 56 omap_gem_dma_sync_buffer(obj, dir); 57 58 return sg; 59 out: 60 kfree(sg); 61 return ERR_PTR(ret); 62 } 63 64 static void omap_gem_unmap_dma_buf(struct dma_buf_attachment *attachment, 65 struct sg_table *sg, enum dma_data_direction dir) 66 { 67 struct drm_gem_object *obj = attachment->dmabuf->priv; 68 omap_gem_unpin(obj); 69 sg_free_table(sg); 70 kfree(sg); 71 } 72 73 static int omap_gem_dmabuf_begin_cpu_access(struct dma_buf *buffer, 74 enum dma_data_direction dir) 75 { 76 struct drm_gem_object *obj = buffer->priv; 77 struct page **pages; 78 if (omap_gem_flags(obj) & OMAP_BO_TILED) { 79 /* TODO we would need to pin at least part of the buffer to 80 * get de-tiled view. For now just reject it. 81 */ 82 return -ENOMEM; 83 } 84 /* make sure we have the pages: */ 85 return omap_gem_get_pages(obj, &pages, true); 86 } 87 88 static int omap_gem_dmabuf_end_cpu_access(struct dma_buf *buffer, 89 enum dma_data_direction dir) 90 { 91 struct drm_gem_object *obj = buffer->priv; 92 omap_gem_put_pages(obj); 93 return 0; 94 } 95 96 97 static void *omap_gem_dmabuf_kmap_atomic(struct dma_buf *buffer, 98 unsigned long page_num) 99 { 100 struct drm_gem_object *obj = buffer->priv; 101 struct page **pages; 102 omap_gem_get_pages(obj, &pages, false); 103 omap_gem_cpu_sync_page(obj, page_num); 104 return kmap_atomic(pages[page_num]); 105 } 106 107 static void omap_gem_dmabuf_kunmap_atomic(struct dma_buf *buffer, 108 unsigned long page_num, void *addr) 109 { 110 kunmap_atomic(addr); 111 } 112 113 static void *omap_gem_dmabuf_kmap(struct dma_buf *buffer, 114 unsigned long page_num) 115 { 116 struct drm_gem_object *obj = buffer->priv; 117 struct page **pages; 118 omap_gem_get_pages(obj, &pages, false); 119 omap_gem_cpu_sync_page(obj, page_num); 120 return kmap(pages[page_num]); 121 } 122 123 static void omap_gem_dmabuf_kunmap(struct dma_buf *buffer, 124 unsigned long page_num, void *addr) 125 { 126 struct drm_gem_object *obj = buffer->priv; 127 struct page **pages; 128 omap_gem_get_pages(obj, &pages, false); 129 kunmap(pages[page_num]); 130 } 131 132 static int omap_gem_dmabuf_mmap(struct dma_buf *buffer, 133 struct vm_area_struct *vma) 134 { 135 struct drm_gem_object *obj = buffer->priv; 136 int ret = 0; 137 138 ret = drm_gem_mmap_obj(obj, omap_gem_mmap_size(obj), vma); 139 if (ret < 0) 140 return ret; 141 142 return omap_gem_mmap_obj(obj, vma); 143 } 144 145 static const struct dma_buf_ops omap_dmabuf_ops = { 146 .map_dma_buf = omap_gem_map_dma_buf, 147 .unmap_dma_buf = omap_gem_unmap_dma_buf, 148 .release = drm_gem_dmabuf_release, 149 .begin_cpu_access = omap_gem_dmabuf_begin_cpu_access, 150 .end_cpu_access = omap_gem_dmabuf_end_cpu_access, 151 .map = omap_gem_dmabuf_kmap, 152 .unmap = omap_gem_dmabuf_kunmap, 153 .mmap = omap_gem_dmabuf_mmap, 154 }; 155 156 struct dma_buf *omap_gem_prime_export(struct drm_device *dev, 157 struct drm_gem_object *obj, int flags) 158 { 159 DEFINE_DMA_BUF_EXPORT_INFO(exp_info); 160 161 exp_info.ops = &omap_dmabuf_ops; 162 exp_info.size = obj->size; 163 exp_info.flags = flags; 164 exp_info.priv = obj; 165 166 return drm_gem_dmabuf_export(dev, &exp_info); 167 } 168 169 /* ----------------------------------------------------------------------------- 170 * DMABUF Import 171 */ 172 173 struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev, 174 struct dma_buf *dma_buf) 175 { 176 struct dma_buf_attachment *attach; 177 struct drm_gem_object *obj; 178 struct sg_table *sgt; 179 int ret; 180 181 if (dma_buf->ops == &omap_dmabuf_ops) { 182 obj = dma_buf->priv; 183 if (obj->dev == dev) { 184 /* 185 * Importing dmabuf exported from out own gem increases 186 * refcount on gem itself instead of f_count of dmabuf. 187 */ 188 drm_gem_object_reference(obj); 189 return obj; 190 } 191 } 192 193 attach = dma_buf_attach(dma_buf, dev->dev); 194 if (IS_ERR(attach)) 195 return ERR_CAST(attach); 196 197 get_dma_buf(dma_buf); 198 199 sgt = dma_buf_map_attachment(attach, DMA_TO_DEVICE); 200 if (IS_ERR(sgt)) { 201 ret = PTR_ERR(sgt); 202 goto fail_detach; 203 } 204 205 obj = omap_gem_new_dmabuf(dev, dma_buf->size, sgt); 206 if (IS_ERR(obj)) { 207 ret = PTR_ERR(obj); 208 goto fail_unmap; 209 } 210 211 obj->import_attach = attach; 212 213 return obj; 214 215 fail_unmap: 216 dma_buf_unmap_attachment(attach, sgt, DMA_TO_DEVICE); 217 fail_detach: 218 dma_buf_detach(dma_buf, attach); 219 dma_buf_put(dma_buf); 220 221 return ERR_PTR(ret); 222 } 223