drivers/gpu/drm/i915/gt/intel_region_lmem.c

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright © 2019 Intel Corporation
   4  */
   5
   6 #include "i915_drv.h"
   7 #include "intel_memory_region.h"
   8 #include "intel_region_lmem.h"
   9 #include "intel_region_ttm.h"
  10 #include "gem/i915_gem_lmem.h"
  11 #include "gem/i915_gem_region.h"
  12 #include "gem/i915_gem_ttm.h"
  13 #include "gt/intel_gt.h"
  14
  15 static int init_fake_lmem_bar(struct intel_memory_region *mem)
  16 {
  17         struct drm_i915_private *i915 = mem->i915;
  18         struct i915_ggtt *ggtt = &i915->ggtt;
  19         unsigned long n;
  20         int ret;
  21
  22         /* We want to 1:1 map the mappable aperture to our reserved region */
  23
  24         mem->fake_mappable.start = 0;
  25         mem->fake_mappable.size = resource_size(&mem->region);
  26         mem->fake_mappable.color = I915_COLOR_UNEVICTABLE;
  27
  28         ret = drm_mm_reserve_node(&ggtt->vm.mm, &mem->fake_mappable);
  29         if (ret)
  30                 return ret;
  31
  32         mem->remap_addr = dma_map_resource(i915->drm.dev,
  33                                            mem->region.start,
  34                                            mem->fake_mappable.size,
  35                                            PCI_DMA_BIDIRECTIONAL,
  36                                            DMA_ATTR_FORCE_CONTIGUOUS);
  37         if (dma_mapping_error(i915->drm.dev, mem->remap_addr)) {
  38                 drm_mm_remove_node(&mem->fake_mappable);
  39                 return -EINVAL;
  40         }
  41
  42         for (n = 0; n < mem->fake_mappable.size >> PAGE_SHIFT; ++n) {
  43                 ggtt->vm.insert_page(&ggtt->vm,
  44                                      mem->remap_addr + (n << PAGE_SHIFT),
  45                                      n << PAGE_SHIFT,
  46                                      I915_CACHE_NONE, 0);
  47         }
  48
  49         mem->region = (struct resource)DEFINE_RES_MEM(mem->remap_addr,
  50                                                       mem->fake_mappable.size);
  51
  52         return 0;
  53 }
  54
  55 static void release_fake_lmem_bar(struct intel_memory_region *mem)
  56 {
  57         if (!drm_mm_node_allocated(&mem->fake_mappable))
  58                 return;
  59
  60         drm_mm_remove_node(&mem->fake_mappable);
  61
  62         dma_unmap_resource(mem->i915->drm.dev,
  63                            mem->remap_addr,
  64                            mem->fake_mappable.size,
  65                            PCI_DMA_BIDIRECTIONAL,
  66                            DMA_ATTR_FORCE_CONTIGUOUS);
  67 }
  68
  69 static void
  70 region_lmem_release(struct intel_memory_region *mem)
  71 {
  72         intel_region_ttm_fini(mem);
  73         io_mapping_fini(&mem->iomap);
  74         release_fake_lmem_bar(mem);
  75 }
  76
  77 static int
  78 region_lmem_init(struct intel_memory_region *mem)
  79 {
  80         int ret;
  81
  82         if (mem->i915->params.fake_lmem_start) {
  83                 ret = init_fake_lmem_bar(mem);
  84                 GEM_BUG_ON(ret);
  85         }
  86
  87         if (!io_mapping_init_wc(&mem->iomap,
  88                                 mem->io_start,
  89                                 resource_size(&mem->region))) {
  90                 ret = -EIO;
  91                 goto out_no_io;
  92         }
  93
  94         ret = intel_region_ttm_init(mem);
  95         if (ret)
  96                 goto out_no_buddy;
  97
  98         return 0;
  99
 100 out_no_buddy:
 101         io_mapping_fini(&mem->iomap);
 102 out_no_io:
 103         release_fake_lmem_bar(mem);
 104
 105         return ret;
 106 }
 107
 108 static const struct intel_memory_region_ops intel_region_lmem_ops = {
 109         .init = region_lmem_init,
 110         .release = region_lmem_release,
 111         .init_object = __i915_gem_ttm_object_init,
 112 };
 113
 114 struct intel_memory_region *
 115 intel_gt_setup_fake_lmem(struct intel_gt *gt)
 116 {
 117         struct drm_i915_private *i915 = gt->i915;
 118         struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
 119         struct intel_memory_region *mem;
 120         resource_size_t mappable_end;
 121         resource_size_t io_start;
 122         resource_size_t start;
 123
 124         if (!HAS_LMEM(i915))
 125                 return ERR_PTR(-ENODEV);
 126
 127         if (!i915->params.fake_lmem_start)
 128                 return ERR_PTR(-ENODEV);
 129
 130         GEM_BUG_ON(i915_ggtt_has_aperture(&i915->ggtt));
 131
 132         /* Your mappable aperture belongs to me now! */
 133         mappable_end = pci_resource_len(pdev, 2);
 134         io_start = pci_resource_start(pdev, 2);
 135         start = i915->params.fake_lmem_start;
 136
 137         mem = intel_memory_region_create(i915,
 138                                          start,
 139                                          mappable_end,
 140                                          PAGE_SIZE,
 141                                          io_start,
 142                                          INTEL_MEMORY_LOCAL,
 143                                          0,
 144                                          &intel_region_lmem_ops);
 145         if (!IS_ERR(mem)) {
 146                 drm_info(&i915->drm, "Intel graphics fake LMEM: %pR\n",
 147                          &mem->region);
 148                 drm_info(&i915->drm,
 149                          "Intel graphics fake LMEM IO start: %llx\n",
 150                         (u64)mem->io_start);
 151                 drm_info(&i915->drm, "Intel graphics fake LMEM size: %llx\n",
 152                          (u64)resource_size(&mem->region));
 153         }
 154
 155         return mem;
 156 }
 157
 158 static bool get_legacy_lowmem_region(struct intel_uncore *uncore,
 159                                      u64 *start, u32 *size)
 160 {
 161         if (!IS_DG1_GT_STEP(uncore->i915, STEP_A0, STEP_C0))
 162                 return false;
 163
 164         *start = 0;
 165         *size = SZ_1M;
 166
 167         drm_dbg(&uncore->i915->drm, "LMEM: reserved legacy low-memory [0x%llx-0x%llx]\n",
 168                 *start, *start + *size);
 169
 170         return true;
 171 }
 172
 173 static int reserve_lowmem_region(struct intel_uncore *uncore,
 174                                  struct intel_memory_region *mem)
 175 {
 176         u64 reserve_start;
 177         u32 reserve_size;
 178         int ret;
 179
 180         if (!get_legacy_lowmem_region(uncore, &reserve_start, &reserve_size))
 181                 return 0;
 182
 183         ret = intel_memory_region_reserve(mem, reserve_start, reserve_size);
 184         if (ret)
 185                 drm_err(&uncore->i915->drm, "LMEM: reserving low memory region failed\n");
 186
 187         return ret;
 188 }
 189
 190 static struct intel_memory_region *setup_lmem(struct intel_gt *gt)
 191 {
 192         struct drm_i915_private *i915 = gt->i915;
 193         struct intel_uncore *uncore = gt->uncore;
 194         struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
 195         struct intel_memory_region *mem;
 196         resource_size_t io_start;
 197         resource_size_t lmem_size;
 198         int err;
 199
 200         if (!IS_DGFX(i915))
 201                 return ERR_PTR(-ENODEV);
 202
 203         /* Stolen starts from GSMBASE on DG1 */
 204         lmem_size = intel_uncore_read64(uncore, GEN12_GSMBASE);
 205
 206         io_start = pci_resource_start(pdev, 2);
 207         if (GEM_WARN_ON(lmem_size > pci_resource_len(pdev, 2)))
 208                 return ERR_PTR(-ENODEV);
 209
 210         mem = intel_memory_region_create(i915,
 211                                          0,
 212                                          lmem_size,
 213                                          I915_GTT_PAGE_SIZE_4K,
 214                                          io_start,
 215                                          INTEL_MEMORY_LOCAL,
 216                                          0,
 217                                          &intel_region_lmem_ops);
 218         if (IS_ERR(mem))
 219                 return mem;
 220
 221         err = reserve_lowmem_region(uncore, mem);
 222         if (err)
 223                 goto err_region_put;
 224
 225         drm_dbg(&i915->drm, "Local memory: %pR\n", &mem->region);
 226         drm_dbg(&i915->drm, "Local memory IO start: %pa\n",
 227                 &mem->io_start);
 228         drm_info(&i915->drm, "Local memory available: %pa\n",
 229                  &lmem_size);
 230
 231         return mem;
 232
 233 err_region_put:
 234         intel_memory_region_put(mem);
 235         return ERR_PTR(err);
 236 }
 237
 238 struct intel_memory_region *intel_gt_setup_lmem(struct intel_gt *gt)
 239 {
 240         return setup_lmem(gt);
 241 }