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
  36 static int vmw_gmr2_bind(struct vmw_private *dev_priv,
  37                          struct page *pages[],
  38                          unsigned long num_pages,
  39                          int gmr_id)
  40 {
  41         SVGAFifoCmdDefineGMR2 define_cmd;
  42         SVGAFifoCmdRemapGMR2 remap_cmd;
  43         uint32_t *cmd;
  44         uint32_t *cmd_orig;
  45         uint32_t define_size = sizeof(define_cmd) + sizeof(*cmd);
  46         uint32_t remap_num = num_pages / VMW_PPN_PER_REMAP + ((num_pages % VMW_PPN_PER_REMAP) > 0);
  47         uint32_t remap_size = VMW_PPN_SIZE * num_pages + (sizeof(remap_cmd) + sizeof(*cmd)) * remap_num;
  48         uint32_t remap_pos = 0;
  49         uint32_t cmd_size = define_size + remap_size;
  50         uint32_t i;
  51
  52         cmd_orig = cmd = vmw_fifo_reserve(dev_priv, cmd_size);
  53         if (unlikely(cmd == NULL))
  54                 return -ENOMEM;
  55
  56         define_cmd.gmrId = gmr_id;
  57         define_cmd.numPages = num_pages;
  58
  59         *cmd++ = SVGA_CMD_DEFINE_GMR2;
  60         memcpy(cmd, &define_cmd, sizeof(define_cmd));
  61         cmd += sizeof(define_cmd) / sizeof(*cmd);
  62
  63         /*
  64          * Need to split the command if there are too many
  65          * pages that goes into the gmr.
  66          */
  67
  68         remap_cmd.gmrId = gmr_id;
  69         remap_cmd.flags = (VMW_PPN_SIZE > sizeof(*cmd)) ?
  70                 SVGA_REMAP_GMR2_PPN64 : SVGA_REMAP_GMR2_PPN32;
  71
  72         while (num_pages > 0) {
  73                 unsigned long nr = min(num_pages, (unsigned long)VMW_PPN_PER_REMAP);
  74
  75                 remap_cmd.offsetPages = remap_pos;
  76                 remap_cmd.numPages = nr;
  77
  78                 *cmd++ = SVGA_CMD_REMAP_GMR2;
  79                 memcpy(cmd, &remap_cmd, sizeof(remap_cmd));
  80                 cmd += sizeof(remap_cmd) / sizeof(*cmd);
  81
  82                 for (i = 0; i < nr; ++i) {
  83                         if (VMW_PPN_SIZE <= 4)
  84                                 *cmd = page_to_pfn(*pages++);
  85                         else
  86                                 *((uint64_t *)cmd) = page_to_pfn(*pages++);
  87
  88                         cmd += VMW_PPN_SIZE / sizeof(*cmd);
  89                 }
  90
  91                 num_pages -= nr;
  92                 remap_pos += nr;
  93         }
  94
  95         BUG_ON(cmd != cmd_orig + cmd_size / sizeof(*cmd));
  96
  97         vmw_fifo_commit(dev_priv, cmd_size);
  98
  99         return 0;
 100 }
 101
 102 static void vmw_gmr2_unbind(struct vmw_private *dev_priv,
 103                             int gmr_id)
 104 {
 105         SVGAFifoCmdDefineGMR2 define_cmd;
 106         uint32_t define_size = sizeof(define_cmd) + 4;
 107         uint32_t *cmd;
 108
 109         cmd = vmw_fifo_reserve(dev_priv, define_size);
 110         if (unlikely(cmd == NULL)) {
 111                 DRM_ERROR("GMR2 unbind failed.\n");
 112                 return;
 113         }
 114         define_cmd.gmrId = gmr_id;
 115         define_cmd.numPages = 0;
 116
 117         *cmd++ = SVGA_CMD_DEFINE_GMR2;
 118         memcpy(cmd, &define_cmd, sizeof(define_cmd));
 119
 120         vmw_fifo_commit(dev_priv, define_size);
 121 }
 122
 123 /**
 124  * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
 125  * the number of used descriptors.
 126  */
 127
 128 static int vmw_gmr_build_descriptors(struct list_head *desc_pages,
 129                                      struct page *pages[],
 130                                      unsigned long num_pages)
 131 {
 132         struct page *page, *next;
 133         struct svga_guest_mem_descriptor *page_virtual = NULL;
 134         struct svga_guest_mem_descriptor *desc_virtual = NULL;
 135         unsigned int desc_per_page;
 136         unsigned long prev_pfn;
 137         unsigned long pfn;
 138         int ret;
 139
 140         desc_per_page = PAGE_SIZE /
 141             sizeof(struct svga_guest_mem_descriptor) - 1;
 142
 143         while (likely(num_pages != 0)) {
 144                 page = alloc_page(__GFP_HIGHMEM);
 145                 if (unlikely(page == NULL)) {
 146                         ret = -ENOMEM;
 147                         goto out_err;
 148                 }
 149
 150                 list_add_tail(&page->lru, desc_pages);
 151
 152                 /*
 153                  * Point previous page terminating descriptor to this
 154                  * page before unmapping it.
 155                  */
 156
 157                 if (likely(page_virtual != NULL)) {
 158                         desc_virtual->ppn = page_to_pfn(page);
 159                         kunmap_atomic(page_virtual);
 160                 }
 161
 162                 page_virtual = kmap_atomic(page);
 163                 desc_virtual = page_virtual - 1;
 164                 prev_pfn = ~(0UL);
 165
 166                 while (likely(num_pages != 0)) {
 167                         pfn = page_to_pfn(*pages);
 168
 169                         if (pfn != prev_pfn + 1) {
 170
 171                                 if (desc_virtual - page_virtual ==
 172                                     desc_per_page - 1)
 173                                         break;
 174
 175                                 (++desc_virtual)->ppn = cpu_to_le32(pfn);
 176                                 desc_virtual->num_pages = cpu_to_le32(1);
 177                         } else {
 178                                 uint32_t tmp =
 179                                     le32_to_cpu(desc_virtual->num_pages);
 180                                 desc_virtual->num_pages = cpu_to_le32(tmp + 1);
 181                         }
 182                         prev_pfn = pfn;
 183                         --num_pages;
 184                         ++pages;
 185                 }
 186
 187                 (++desc_virtual)->ppn = cpu_to_le32(0);
 188                 desc_virtual->num_pages = cpu_to_le32(0);
 189         }
 190
 191         if (likely(page_virtual != NULL))
 192                 kunmap_atomic(page_virtual);
 193
 194         return 0;
 195 out_err:
 196         list_for_each_entry_safe(page, next, desc_pages, lru) {
 197                 list_del_init(&page->lru);
 198                 __free_page(page);
 199         }
 200         return ret;
 201 }
 202
 203 static inline void vmw_gmr_free_descriptors(struct list_head *desc_pages)
 204 {
 205         struct page *page, *next;
 206
 207         list_for_each_entry_safe(page, next, desc_pages, lru) {
 208                 list_del_init(&page->lru);
 209                 __free_page(page);
 210         }
 211 }
 212
 213 static void vmw_gmr_fire_descriptors(struct vmw_private *dev_priv,
 214                                      int gmr_id, struct list_head *desc_pages)
 215 {
 216         struct page *page;
 217
 218         if (unlikely(list_empty(desc_pages)))
 219                 return;
 220
 221         page = list_entry(desc_pages->next, struct page, lru);
 222
 223         mutex_lock(&dev_priv->hw_mutex);
 224
 225         vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
 226         wmb();
 227         vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, page_to_pfn(page));
 228         mb();
 229
 230         mutex_unlock(&dev_priv->hw_mutex);
 231
 232 }
 233
 234 /**
 235  * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
 236  * the number of used descriptors.
 237  */
 238
 239 static unsigned long vmw_gmr_count_descriptors(struct page *pages[],
 240                                         unsigned long num_pages)
 241 {
 242         unsigned long prev_pfn = ~(0UL);
 243         unsigned long pfn;
 244         unsigned long descriptors = 0;
 245
 246         while (num_pages--) {
 247                 pfn = page_to_pfn(*pages++);
 248                 if (prev_pfn + 1 != pfn)
 249                         ++descriptors;
 250                 prev_pfn = pfn;
 251         }
 252
 253         return descriptors;
 254 }
 255
 256 int vmw_gmr_bind(struct vmw_private *dev_priv,
 257                  struct page *pages[],
 258                  unsigned long num_pages,
 259                  int gmr_id)
 260 {
 261         struct list_head desc_pages;
 262         int ret;
 263
 264         if (likely(dev_priv->capabilities & SVGA_CAP_GMR2))
 265                 return vmw_gmr2_bind(dev_priv, pages, num_pages, gmr_id);
 266
 267         if (unlikely(!(dev_priv->capabilities & SVGA_CAP_GMR)))
 268                 return -EINVAL;
 269
 270         if (vmw_gmr_count_descriptors(pages, num_pages) >
 271             dev_priv->max_gmr_descriptors)
 272                 return -EINVAL;
 273
 274         INIT_LIST_HEAD(&desc_pages);
 275
 276         ret = vmw_gmr_build_descriptors(&desc_pages, pages, num_pages);
 277         if (unlikely(ret != 0))
 278                 return ret;
 279
 280         vmw_gmr_fire_descriptors(dev_priv, gmr_id, &desc_pages);
 281         vmw_gmr_free_descriptors(&desc_pages);
 282
 283         return 0;
 284 }
 285
 286
 287 void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id)
 288 {
 289         if (likely(dev_priv->capabilities & SVGA_CAP_GMR2)) {
 290                 vmw_gmr2_unbind(dev_priv, gmr_id);
 291                 return;
 292         }
 293
 294         mutex_lock(&dev_priv->hw_mutex);
 295         vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
 296         wmb();
 297         vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, 0);
 298         mb();
 299         mutex_unlock(&dev_priv->hw_mutex);
 300 }