drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c

   1 /**************************************************************************
   2  *
   3  * Copyright © 2009-2011 VMware, Inc., Palo Alto, CA., USA
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 #include "vmwgfx_drv.h"
  29 #include <drm/drmP.h>
  30 #include <drm/ttm/ttm_bo_driver.h>
  31
  32 #define VMW_PPN_SIZE (sizeof(unsigned long))
  33 /* A future safe maximum remap size. */
  34 #define VMW_PPN_PER_REMAP ((31 * 1024) / VMW_PPN_SIZE)
  35 #define DMA_ADDR_INVALID ((dma_addr_t) 0)
  36 #define DMA_PAGE_INVALID 0UL
  37
  38 static int vmw_gmr2_bind(struct vmw_private *dev_priv,
  39                          struct vmw_piter *iter,
  40                          unsigned long num_pages,
  41                          int gmr_id)
  42 {
  43         SVGAFifoCmdDefineGMR2 define_cmd;
  44         SVGAFifoCmdRemapGMR2 remap_cmd;
  45         uint32_t *cmd;
  46         uint32_t *cmd_orig;
  47         uint32_t define_size = sizeof(define_cmd) + sizeof(*cmd);
  48         uint32_t remap_num = num_pages / VMW_PPN_PER_REMAP + ((num_pages % VMW_PPN_PER_REMAP) > 0);
  49         uint32_t remap_size = VMW_PPN_SIZE * num_pages + (sizeof(remap_cmd) + sizeof(*cmd)) * remap_num;
  50         uint32_t remap_pos = 0;
  51         uint32_t cmd_size = define_size + remap_size;
  52         uint32_t i;
  53
  54         cmd_orig = cmd = vmw_fifo_reserve(dev_priv, cmd_size);
  55         if (unlikely(cmd == NULL))
  56                 return -ENOMEM;
  57
  58         define_cmd.gmrId = gmr_id;
  59         define_cmd.numPages = num_pages;
  60
  61         *cmd++ = SVGA_CMD_DEFINE_GMR2;
  62         memcpy(cmd, &define_cmd, sizeof(define_cmd));
  63         cmd += sizeof(define_cmd) / sizeof(*cmd);
  64
  65         /*
  66          * Need to split the command if there are too many
  67          * pages that goes into the gmr.
  68          */
  69
  70         remap_cmd.gmrId = gmr_id;
  71         remap_cmd.flags = (VMW_PPN_SIZE > sizeof(*cmd)) ?
  72                 SVGA_REMAP_GMR2_PPN64 : SVGA_REMAP_GMR2_PPN32;
  73
  74         while (num_pages > 0) {
  75                 unsigned long nr = min(num_pages, (unsigned long)VMW_PPN_PER_REMAP);
  76
  77                 remap_cmd.offsetPages = remap_pos;
  78                 remap_cmd.numPages = nr;
  79
  80                 *cmd++ = SVGA_CMD_REMAP_GMR2;
  81                 memcpy(cmd, &remap_cmd, sizeof(remap_cmd));
  82                 cmd += sizeof(remap_cmd) / sizeof(*cmd);
  83
  84                 for (i = 0; i < nr; ++i) {
  85                         if (VMW_PPN_SIZE <= 4)
  86                                 *cmd = vmw_piter_dma_addr(iter) >> PAGE_SHIFT;
  87                         else
  88                                 *((uint64_t *)cmd) = vmw_piter_dma_addr(iter) >>
  89                                         PAGE_SHIFT;
  90
  91                         cmd += VMW_PPN_SIZE / sizeof(*cmd);
  92                         vmw_piter_next(iter);
  93                 }
  94
  95                 num_pages -= nr;
  96                 remap_pos += nr;
  97         }
  98
  99         BUG_ON(cmd != cmd_orig + cmd_size / sizeof(*cmd));
 100
 101         vmw_fifo_commit(dev_priv, cmd_size);
 102
 103         return 0;
 104 }
 105
 106 static void vmw_gmr2_unbind(struct vmw_private *dev_priv,
 107                             int gmr_id)
 108 {
 109         SVGAFifoCmdDefineGMR2 define_cmd;
 110         uint32_t define_size = sizeof(define_cmd) + 4;
 111         uint32_t *cmd;
 112
 113         cmd = vmw_fifo_reserve(dev_priv, define_size);
 114         if (unlikely(cmd == NULL)) {
 115                 DRM_ERROR("GMR2 unbind failed.\n");
 116                 return;
 117         }
 118         define_cmd.gmrId = gmr_id;
 119         define_cmd.numPages = 0;
 120
 121         *cmd++ = SVGA_CMD_DEFINE_GMR2;
 122         memcpy(cmd, &define_cmd, sizeof(define_cmd));
 123
 124         vmw_fifo_commit(dev_priv, define_size);
 125 }
 126
 127
 128 static void vmw_gmr_free_descriptors(struct device *dev, dma_addr_t desc_dma,
 129                                      struct list_head *desc_pages)
 130 {
 131         struct page *page, *next;
 132         struct svga_guest_mem_descriptor *page_virtual;
 133         unsigned int desc_per_page = PAGE_SIZE /
 134                 sizeof(struct svga_guest_mem_descriptor) - 1;
 135
 136         if (list_empty(desc_pages))
 137                 return;
 138
 139         list_for_each_entry_safe(page, next, desc_pages, lru) {
 140                 list_del_init(&page->lru);
 141
 142                 if (likely(desc_dma != DMA_ADDR_INVALID)) {
 143                         dma_unmap_page(dev, desc_dma, PAGE_SIZE,
 144                                        DMA_TO_DEVICE);
 145                 }
 146
 147                 page_virtual = kmap_atomic(page);
 148                 desc_dma = page_virtual[desc_per_page].ppn << PAGE_SHIFT;
 149                 kunmap_atomic(page_virtual);
 150
 151                 __free_page(page);
 152         }
 153 }
 154
 155 /**
 156  * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
 157  * the number of used descriptors.
 158  *
 159  */
 160
 161 static int vmw_gmr_build_descriptors(struct device *dev,
 162                                      struct list_head *desc_pages,
 163                                      struct vmw_piter *iter,
 164                                      unsigned long num_pages,
 165                                      dma_addr_t *first_dma)
 166 {
 167         struct page *page;
 168         struct svga_guest_mem_descriptor *page_virtual = NULL;
 169         struct svga_guest_mem_descriptor *desc_virtual = NULL;
 170         unsigned int desc_per_page;
 171         unsigned long prev_pfn;
 172         unsigned long pfn;
 173         int ret;
 174         dma_addr_t desc_dma;
 175
 176         desc_per_page = PAGE_SIZE /
 177             sizeof(struct svga_guest_mem_descriptor) - 1;
 178
 179         while (likely(num_pages != 0)) {
 180                 page = alloc_page(__GFP_HIGHMEM);
 181                 if (unlikely(page == NULL)) {
 182                         ret = -ENOMEM;
 183                         goto out_err;
 184                 }
 185
 186                 list_add_tail(&page->lru, desc_pages);
 187                 page_virtual = kmap_atomic(page);
 188                 desc_virtual = page_virtual - 1;
 189                 prev_pfn = ~(0UL);
 190
 191                 while (likely(num_pages != 0)) {
 192                         pfn = vmw_piter_dma_addr(iter) >> PAGE_SHIFT;
 193
 194                         if (pfn != prev_pfn + 1) {
 195
 196                                 if (desc_virtual - page_virtual ==
 197                                     desc_per_page - 1)
 198                                         break;
 199
 200                                 (++desc_virtual)->ppn = cpu_to_le32(pfn);
 201                                 desc_virtual->num_pages = cpu_to_le32(1);
 202                         } else {
 203                                 uint32_t tmp =
 204                                     le32_to_cpu(desc_virtual->num_pages);
 205                                 desc_virtual->num_pages = cpu_to_le32(tmp + 1);
 206                         }
 207                         prev_pfn = pfn;
 208                         --num_pages;
 209                         vmw_piter_next(iter);
 210                 }
 211
 212                 (++desc_virtual)->ppn = DMA_PAGE_INVALID;
 213                 desc_virtual->num_pages = cpu_to_le32(0);
 214                 kunmap_atomic(page_virtual);
 215         }
 216
 217         desc_dma = 0;
 218         list_for_each_entry_reverse(page, desc_pages, lru) {
 219                 page_virtual = kmap_atomic(page);
 220                 page_virtual[desc_per_page].ppn = desc_dma >> PAGE_SHIFT;
 221                 kunmap_atomic(page_virtual);
 222                 desc_dma = dma_map_page(dev, page, 0, PAGE_SIZE,
 223                                         DMA_TO_DEVICE);
 224
 225                 if (unlikely(dma_mapping_error(dev, desc_dma)))
 226                         goto out_err;
 227         }
 228         *first_dma = desc_dma;
 229
 230         return 0;
 231 out_err:
 232         vmw_gmr_free_descriptors(dev, DMA_ADDR_INVALID, desc_pages);
 233         return ret;
 234 }
 235
 236 static void vmw_gmr_fire_descriptors(struct vmw_private *dev_priv,
 237                                      int gmr_id, dma_addr_t desc_dma)
 238 {
 239         mutex_lock(&dev_priv->hw_mutex);
 240
 241         vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
 242         wmb();
 243         vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, desc_dma >> PAGE_SHIFT);
 244         mb();
 245
 246         mutex_unlock(&dev_priv->hw_mutex);
 247
 248 }
 249
 250 int vmw_gmr_bind(struct vmw_private *dev_priv,
 251                  const struct vmw_sg_table *vsgt,
 252                  unsigned long num_pages,
 253                  int gmr_id)
 254 {
 255         struct list_head desc_pages;
 256         dma_addr_t desc_dma = 0;
 257         struct device *dev = dev_priv->dev->dev;
 258         struct vmw_piter data_iter;
 259         int ret;
 260
 261         vmw_piter_start(&data_iter, vsgt, 0);
 262
 263         if (unlikely(!vmw_piter_next(&data_iter)))
 264                 return 0;
 265
 266         if (likely(dev_priv->capabilities & SVGA_CAP_GMR2))
 267                 return vmw_gmr2_bind(dev_priv, &data_iter, num_pages, gmr_id);
 268
 269         if (unlikely(!(dev_priv->capabilities & SVGA_CAP_GMR)))
 270                 return -EINVAL;
 271
 272         if (vsgt->num_regions > dev_priv->max_gmr_descriptors)
 273                 return -EINVAL;
 274
 275         INIT_LIST_HEAD(&desc_pages);
 276
 277         ret = vmw_gmr_build_descriptors(dev, &desc_pages, &data_iter,
 278                                         num_pages, &desc_dma);
 279         if (unlikely(ret != 0))
 280                 return ret;
 281
 282         vmw_gmr_fire_descriptors(dev_priv, gmr_id, desc_dma);
 283         vmw_gmr_free_descriptors(dev, desc_dma, &desc_pages);
 284
 285         return 0;
 286 }
 287
 288
 289 void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id)
 290 {
 291         if (likely(dev_priv->capabilities & SVGA_CAP_GMR2)) {
 292                 vmw_gmr2_unbind(dev_priv, gmr_id);
 293                 return;
 294         }
 295
 296         mutex_lock(&dev_priv->hw_mutex);
 297         vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
 298         wmb();
 299         vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, 0);
 300         mb();
 301         mutex_unlock(&dev_priv->hw_mutex);
 302 }