1 /* $NetBSD: intel_region_lmem.c,v 1.2 2021/12/18 23:45:28 riastradh Exp $ */
2
3 // SPDX-License-Identifier: MIT
4 /*
5 * Copyright © 2019 Intel Corporation
6 */
7
8 #include <sys/cdefs.h>
9 __KERNEL_RCSID(0, "$NetBSD: intel_region_lmem.c,v 1.2 2021/12/18 23:45:28 riastradh Exp $");
10
11 #include "i915_drv.h"
12 #include "intel_memory_region.h"
13 #include "gem/i915_gem_lmem.h"
14 #include "gem/i915_gem_region.h"
15 #include "intel_region_lmem.h"
16
init_fake_lmem_bar(struct intel_memory_region * mem)17 static int init_fake_lmem_bar(struct intel_memory_region *mem)
18 {
19 struct drm_i915_private *i915 = mem->i915;
20 struct i915_ggtt *ggtt = &i915->ggtt;
21 unsigned long n;
22 int ret;
23
24 /* We want to 1:1 map the mappable aperture to our reserved region */
25
26 mem->fake_mappable.start = 0;
27 mem->fake_mappable.size = resource_size(&mem->region);
28 mem->fake_mappable.color = I915_COLOR_UNEVICTABLE;
29
30 ret = drm_mm_reserve_node(&ggtt->vm.mm, &mem->fake_mappable);
31 if (ret)
32 return ret;
33
34 mem->remap_addr = dma_map_resource(&i915->drm.pdev->dev,
35 mem->region.start,
36 mem->fake_mappable.size,
37 PCI_DMA_BIDIRECTIONAL,
38 DMA_ATTR_FORCE_CONTIGUOUS);
39 if (dma_mapping_error(&i915->drm.pdev->dev, mem->remap_addr)) {
40 drm_mm_remove_node(&mem->fake_mappable);
41 return -EINVAL;
42 }
43
44 for (n = 0; n < mem->fake_mappable.size >> PAGE_SHIFT; ++n) {
45 ggtt->vm.insert_page(&ggtt->vm,
46 mem->remap_addr + (n << PAGE_SHIFT),
47 n << PAGE_SHIFT,
48 I915_CACHE_NONE, 0);
49 }
50
51 mem->region = (struct resource)DEFINE_RES_MEM(mem->remap_addr,
52 mem->fake_mappable.size);
53
54 return 0;
55 }
56
release_fake_lmem_bar(struct intel_memory_region * mem)57 static void release_fake_lmem_bar(struct intel_memory_region *mem)
58 {
59 if (!drm_mm_node_allocated(&mem->fake_mappable))
60 return;
61
62 drm_mm_remove_node(&mem->fake_mappable);
63
64 dma_unmap_resource(&mem->i915->drm.pdev->dev,
65 mem->remap_addr,
66 mem->fake_mappable.size,
67 PCI_DMA_BIDIRECTIONAL,
68 DMA_ATTR_FORCE_CONTIGUOUS);
69 }
70
71 static void
region_lmem_release(struct intel_memory_region * mem)72 region_lmem_release(struct intel_memory_region *mem)
73 {
74 release_fake_lmem_bar(mem);
75 io_mapping_fini(&mem->iomap);
76 intel_memory_region_release_buddy(mem);
77 }
78
79 static int
region_lmem_init(struct intel_memory_region * mem)80 region_lmem_init(struct intel_memory_region *mem)
81 {
82 int ret;
83
84 if (i915_modparams.fake_lmem_start) {
85 ret = init_fake_lmem_bar(mem);
86 GEM_BUG_ON(ret);
87 }
88
89 if (!io_mapping_init_wc(&mem->iomap,
90 mem->io_start,
91 resource_size(&mem->region)))
92 return -EIO;
93
94 ret = intel_memory_region_init_buddy(mem);
95 if (ret)
96 io_mapping_fini(&mem->iomap);
97
98 intel_memory_region_set_name(mem, "local");
99
100 return ret;
101 }
102
103 const struct intel_memory_region_ops intel_region_lmem_ops = {
104 .init = region_lmem_init,
105 .release = region_lmem_release,
106 .create_object = __i915_gem_lmem_object_create,
107 };
108
109 struct intel_memory_region *
intel_setup_fake_lmem(struct drm_i915_private * i915)110 intel_setup_fake_lmem(struct drm_i915_private *i915)
111 {
112 struct pci_dev *pdev = i915->drm.pdev;
113 struct intel_memory_region *mem;
114 resource_size_t mappable_end;
115 resource_size_t io_start;
116 resource_size_t start;
117
118 GEM_BUG_ON(i915_ggtt_has_aperture(&i915->ggtt));
119 GEM_BUG_ON(!i915_modparams.fake_lmem_start);
120
121 /* Your mappable aperture belongs to me now! */
122 mappable_end = pci_resource_len(pdev, 2);
123 io_start = pci_resource_start(pdev, 2),
124 start = i915_modparams.fake_lmem_start;
125
126 mem = intel_memory_region_create(i915,
127 start,
128 mappable_end,
129 PAGE_SIZE,
130 io_start,
131 &intel_region_lmem_ops);
132 if (!IS_ERR(mem)) {
133 drm_info(&i915->drm, "Intel graphics fake LMEM: %pR\n",
134 &mem->region);
135 drm_info(&i915->drm,
136 "Intel graphics fake LMEM IO start: %llx\n",
137 (u64)mem->io_start);
138 drm_info(&i915->drm, "Intel graphics fake LMEM size: %llx\n",
139 (u64)resource_size(&mem->region));
140 }
141
142 return mem;
143 }
144