drivers/gpu/drm/i915/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 "gem/i915_gem_lmem.h"
   9 #include "gem/i915_gem_region.h"
  10 #include "intel_region_lmem.h"
  11
  12 static int init_fake_lmem_bar(struct intel_memory_region *mem)
  13 {
  14         struct drm_i915_private *i915 = mem->i915;
  15         struct i915_ggtt *ggtt = &i915->ggtt;
  16         unsigned long n;
  17         int ret;
  18
  19         /* We want to 1:1 map the mappable aperture to our reserved region */
  20
  21         mem->fake_mappable.start = 0;
  22         mem->fake_mappable.size = resource_size(&mem->region);
  23         mem->fake_mappable.color = I915_COLOR_UNEVICTABLE;
  24
  25         ret = drm_mm_reserve_node(&ggtt->vm.mm, &mem->fake_mappable);
  26         if (ret)
  27                 return ret;
  28
  29         mem->remap_addr = dma_map_resource(&i915->drm.pdev->dev,
  30                                            mem->region.start,
  31                                            mem->fake_mappable.size,
  32                                            PCI_DMA_BIDIRECTIONAL,
  33                                            DMA_ATTR_FORCE_CONTIGUOUS);
  34         if (dma_mapping_error(&i915->drm.pdev->dev, mem->remap_addr)) {
  35                 drm_mm_remove_node(&mem->fake_mappable);
  36                 return -EINVAL;
  37         }
  38
  39         for (n = 0; n < mem->fake_mappable.size >> PAGE_SHIFT; ++n) {
  40                 ggtt->vm.insert_page(&ggtt->vm,
  41                                      mem->remap_addr + (n << PAGE_SHIFT),
  42                                      n << PAGE_SHIFT,
  43                                      I915_CACHE_NONE, 0);
  44         }
  45
  46         mem->region = (struct resource)DEFINE_RES_MEM(mem->remap_addr,
  47                                                       mem->fake_mappable.size);
  48
  49         return 0;
  50 }
  51
  52 static void release_fake_lmem_bar(struct intel_memory_region *mem)
  53 {
  54         if (drm_mm_node_allocated(&mem->fake_mappable))
  55                 drm_mm_remove_node(&mem->fake_mappable);
  56
  57         dma_unmap_resource(&mem->i915->drm.pdev->dev,
  58                            mem->remap_addr,
  59                            mem->fake_mappable.size,
  60                            PCI_DMA_BIDIRECTIONAL,
  61                            DMA_ATTR_FORCE_CONTIGUOUS);
  62 }
  63
  64 static void
  65 region_lmem_release(struct intel_memory_region *mem)
  66 {
  67         release_fake_lmem_bar(mem);
  68         io_mapping_fini(&mem->iomap);
  69         intel_memory_region_release_buddy(mem);
  70 }
  71
  72 static int
  73 region_lmem_init(struct intel_memory_region *mem)
  74 {
  75         int ret;
  76
  77         if (i915_modparams.fake_lmem_start) {
  78                 ret = init_fake_lmem_bar(mem);
  79                 GEM_BUG_ON(ret);
  80         }
  81
  82         if (!io_mapping_init_wc(&mem->iomap,
  83                                 mem->io_start,
  84                                 resource_size(&mem->region)))
  85                 return -EIO;
  86
  87         ret = intel_memory_region_init_buddy(mem);
  88         if (ret)
  89                 io_mapping_fini(&mem->iomap);
  90
  91         return ret;
  92 }
  93
  94 const struct intel_memory_region_ops intel_region_lmem_ops = {
  95         .init = region_lmem_init,
  96         .release = region_lmem_release,
  97         .create_object = __i915_gem_lmem_object_create,
  98 };
  99
 100 struct intel_memory_region *
 101 intel_setup_fake_lmem(struct drm_i915_private *i915)
 102 {
 103         struct pci_dev *pdev = i915->drm.pdev;
 104         struct intel_memory_region *mem;
 105         resource_size_t mappable_end;
 106         resource_size_t io_start;
 107         resource_size_t start;
 108
 109         GEM_BUG_ON(i915_ggtt_has_aperture(&i915->ggtt));
 110         GEM_BUG_ON(!i915_modparams.fake_lmem_start);
 111
 112         /* Your mappable aperture belongs to me now! */
 113         mappable_end = pci_resource_len(pdev, 2);
 114         io_start = pci_resource_start(pdev, 2),
 115         start = i915_modparams.fake_lmem_start;
 116
 117         mem = intel_memory_region_create(i915,
 118                                          start,
 119                                          mappable_end,
 120                                          PAGE_SIZE,
 121                                          io_start,
 122                                          &intel_region_lmem_ops);
 123         if (!IS_ERR(mem)) {
 124                 DRM_INFO("Intel graphics fake LMEM: %pR\n", &mem->region);
 125                 DRM_INFO("Intel graphics fake LMEM IO start: %llx\n",
 126                          (u64)mem->io_start);
 127                 DRM_INFO("Intel graphics fake LMEM size: %llx\n",
 128                          (u64)resource_size(&mem->region));
 129         }
 130
 131         return mem;
 132 }