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
  34 static int vmw_gmr2_bind(struct vmw_private *dev_priv,
  35                          struct page *pages[],
  36                          unsigned long num_pages,
  37                          int gmr_id)
  38 {
  39         SVGAFifoCmdDefineGMR2 define_cmd;
  40         SVGAFifoCmdRemapGMR2 remap_cmd;
  41         uint32_t define_size = sizeof(define_cmd) + 4;
  42         uint32_t remap_size = VMW_PPN_SIZE * num_pages + sizeof(remap_cmd) + 4;
  43         uint32_t *cmd;
  44         uint32_t *cmd_orig;
  45         uint32_t i;
  46
  47         cmd_orig = cmd = vmw_fifo_reserve(dev_priv, define_size + remap_size);
  48         if (unlikely(cmd == NULL))
  49                 return -ENOMEM;
  50
  51         define_cmd.gmrId = gmr_id;
  52         define_cmd.numPages = num_pages;
  53
  54         remap_cmd.gmrId = gmr_id;
  55         remap_cmd.flags = (VMW_PPN_SIZE > sizeof(*cmd)) ?
  56                 SVGA_REMAP_GMR2_PPN64 : SVGA_REMAP_GMR2_PPN32;
  57         remap_cmd.offsetPages = 0;
  58         remap_cmd.numPages = num_pages;
  59
  60         *cmd++ = SVGA_CMD_DEFINE_GMR2;
  61         memcpy(cmd, &define_cmd, sizeof(define_cmd));
  62         cmd += sizeof(define_cmd) / sizeof(uint32);
  63
  64         *cmd++ = SVGA_CMD_REMAP_GMR2;
  65         memcpy(cmd, &remap_cmd, sizeof(remap_cmd));
  66         cmd += sizeof(remap_cmd) / sizeof(uint32);
  67
  68         for (i = 0; i < num_pages; ++i) {
  69                 if (VMW_PPN_SIZE <= 4)
  70                         *cmd = page_to_pfn(*pages++);
  71                 else
  72                         *((uint64_t *)cmd) = page_to_pfn(*pages++);
  73
  74                 cmd += VMW_PPN_SIZE / sizeof(*cmd);
  75         }
  76
  77         vmw_fifo_commit(dev_priv, define_size + remap_size);
  78
  79         return 0;
  80 }
  81
  82 static void vmw_gmr2_unbind(struct vmw_private *dev_priv,
  83                             int gmr_id)
  84 {
  85         SVGAFifoCmdDefineGMR2 define_cmd;
  86         uint32_t define_size = sizeof(define_cmd) + 4;
  87         uint32_t *cmd;
  88
  89         cmd = vmw_fifo_reserve(dev_priv, define_size);
  90         if (unlikely(cmd == NULL)) {
  91                 DRM_ERROR("GMR2 unbind failed.\n");
  92                 return;
  93         }
  94         define_cmd.gmrId = gmr_id;
  95         define_cmd.numPages = 0;
  96
  97         *cmd++ = SVGA_CMD_DEFINE_GMR2;
  98         memcpy(cmd, &define_cmd, sizeof(define_cmd));
  99
 100         vmw_fifo_commit(dev_priv, define_size);
 101 }
 102
 103 /**
 104  * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
 105  * the number of used descriptors.
 106  */
 107
 108 static int vmw_gmr_build_descriptors(struct list_head *desc_pages,
 109                                      struct page *pages[],
 110                                      unsigned long num_pages)
 111 {
 112         struct page *page, *next;
 113         struct svga_guest_mem_descriptor *page_virtual = NULL;
 114         struct svga_guest_mem_descriptor *desc_virtual = NULL;
 115         unsigned int desc_per_page;
 116         unsigned long prev_pfn;
 117         unsigned long pfn;
 118         int ret;
 119
 120         desc_per_page = PAGE_SIZE /
 121             sizeof(struct svga_guest_mem_descriptor) - 1;
 122
 123         while (likely(num_pages != 0)) {
 124                 page = alloc_page(__GFP_HIGHMEM);
 125                 if (unlikely(page == NULL)) {
 126                         ret = -ENOMEM;
 127                         goto out_err;
 128                 }
 129
 130                 list_add_tail(&page->lru, desc_pages);
 131
 132                 /*
 133                  * Point previous page terminating descriptor to this
 134                  * page before unmapping it.
 135                  */
 136
 137                 if (likely(page_virtual != NULL)) {
 138                         desc_virtual->ppn = page_to_pfn(page);
 139                         kunmap_atomic(page_virtual);
 140                 }
 141
 142                 page_virtual = kmap_atomic(page);
 143                 desc_virtual = page_virtual - 1;
 144                 prev_pfn = ~(0UL);
 145
 146                 while (likely(num_pages != 0)) {
 147                         pfn = page_to_pfn(*pages);
 148
 149                         if (pfn != prev_pfn + 1) {
 150
 151                                 if (desc_virtual - page_virtual ==
 152                                     desc_per_page - 1)
 153                                         break;
 154
 155                                 (++desc_virtual)->ppn = cpu_to_le32(pfn);
 156                                 desc_virtual->num_pages = cpu_to_le32(1);
 157                         } else {
 158                                 uint32_t tmp =
 159                                     le32_to_cpu(desc_virtual->num_pages);
 160                                 desc_virtual->num_pages = cpu_to_le32(tmp + 1);
 161                         }
 162                         prev_pfn = pfn;
 163                         --num_pages;
 164                         ++pages;
 165                 }
 166
 167                 (++desc_virtual)->ppn = cpu_to_le32(0);
 168                 desc_virtual->num_pages = cpu_to_le32(0);
 169         }
 170
 171         if (likely(page_virtual != NULL))
 172                 kunmap_atomic(page_virtual);
 173
 174         return 0;
 175 out_err:
 176         list_for_each_entry_safe(page, next, desc_pages, lru) {
 177                 list_del_init(&page->lru);
 178                 __free_page(page);
 179         }
 180         return ret;
 181 }
 182
 183 static inline void vmw_gmr_free_descriptors(struct list_head *desc_pages)
 184 {
 185         struct page *page, *next;
 186
 187         list_for_each_entry_safe(page, next, desc_pages, lru) {
 188                 list_del_init(&page->lru);
 189                 __free_page(page);
 190         }
 191 }
 192
 193 static void vmw_gmr_fire_descriptors(struct vmw_private *dev_priv,
 194                                      int gmr_id, struct list_head *desc_pages)
 195 {
 196         struct page *page;
 197
 198         if (unlikely(list_empty(desc_pages)))
 199                 return;
 200
 201         page = list_entry(desc_pages->next, struct page, lru);
 202
 203         mutex_lock(&dev_priv->hw_mutex);
 204
 205         vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
 206         wmb();
 207         vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, page_to_pfn(page));
 208         mb();
 209
 210         mutex_unlock(&dev_priv->hw_mutex);
 211
 212 }
 213
 214 /**
 215  * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
 216  * the number of used descriptors.
 217  */
 218
 219 static unsigned long vmw_gmr_count_descriptors(struct page *pages[],
 220                                         unsigned long num_pages)
 221 {
 222         unsigned long prev_pfn = ~(0UL);
 223         unsigned long pfn;
 224         unsigned long descriptors = 0;
 225
 226         while (num_pages--) {
 227                 pfn = page_to_pfn(*pages++);
 228                 if (prev_pfn + 1 != pfn)
 229                         ++descriptors;
 230                 prev_pfn = pfn;
 231         }
 232
 233         return descriptors;
 234 }
 235
 236 int vmw_gmr_bind(struct vmw_private *dev_priv,
 237                  struct page *pages[],
 238                  unsigned long num_pages,
 239                  int gmr_id)
 240 {
 241         struct list_head desc_pages;
 242         int ret;
 243
 244         if (likely(dev_priv->capabilities & SVGA_CAP_GMR2))
 245                 return vmw_gmr2_bind(dev_priv, pages, num_pages, gmr_id);
 246
 247         if (unlikely(!(dev_priv->capabilities & SVGA_CAP_GMR)))
 248                 return -EINVAL;
 249
 250         if (vmw_gmr_count_descriptors(pages, num_pages) >
 251             dev_priv->max_gmr_descriptors)
 252                 return -EINVAL;
 253
 254         INIT_LIST_HEAD(&desc_pages);
 255
 256         ret = vmw_gmr_build_descriptors(&desc_pages, pages, num_pages);
 257         if (unlikely(ret != 0))
 258                 return ret;
 259
 260         vmw_gmr_fire_descriptors(dev_priv, gmr_id, &desc_pages);
 261         vmw_gmr_free_descriptors(&desc_pages);
 262
 263         return 0;
 264 }
 265
 266
 267 void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id)
 268 {
 269         if (likely(dev_priv->capabilities & SVGA_CAP_GMR2)) {
 270                 vmw_gmr2_unbind(dev_priv, gmr_id);
 271                 return;
 272         }
 273
 274         mutex_lock(&dev_priv->hw_mutex);
 275         vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
 276         wmb();
 277         vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, 0);
 278         mb();
 279         mutex_unlock(&dev_priv->hw_mutex);
 280 }