1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2019 Intel Corporation
4 */
5
6#include "i915_drv.h"
7#include "i915_pci.h"
8#include "i915_reg.h"
9#include "intel_memory_region.h"
10#include "intel_pci_config.h"
11#include "intel_region_lmem.h"
12#include "intel_region_ttm.h"
13#include "gem/i915_gem_lmem.h"
14#include "gem/i915_gem_region.h"
15#include "gem/i915_gem_ttm.h"
16#include "gt/intel_gt.h"
17#include "gt/intel_gt_mcr.h"
18#include "gt/intel_gt_regs.h"
19
20#ifdef CONFIG_64BIT
21static void _release_bars(struct pci_dev *pdev)
22{
23 int resno;
24
25 for (resno = PCI_STD_RESOURCES; resno < PCI_STD_RESOURCE_END; resno++) {
26 if (pci_resource_len(pdev, resno))
27 pci_release_resource(dev: pdev, resno);
28 }
29}
30
31static void
32_resize_bar(struct drm_i915_private *i915, int resno, resource_size_t size)
33{
34 struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
35 int bar_size = pci_rebar_bytes_to_size(bytes: size);
36 int ret;
37
38 _release_bars(pdev);
39
40 ret = pci_resize_resource(dev: pdev, i: resno, size: bar_size);
41 if (ret) {
42 drm_info(&i915->drm, "Failed to resize BAR%d to %dM (%pe)\n",
43 resno, 1 << bar_size, ERR_PTR(ret));
44 return;
45 }
46
47 drm_info(&i915->drm, "BAR%d resized to %dM\n", resno, 1 << bar_size);
48}
49
50static void i915_resize_lmem_bar(struct drm_i915_private *i915, resource_size_t lmem_size)
51{
52 struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
53 struct pci_bus *root = pdev->bus;
54 struct resource *root_res;
55 resource_size_t rebar_size;
56 resource_size_t current_size;
57 intel_wakeref_t wakeref;
58 u32 pci_cmd;
59 int i;
60
61 current_size = roundup_pow_of_two(pci_resource_len(pdev, GEN12_LMEM_BAR));
62
63 if (i915->params.lmem_bar_size) {
64 u32 bar_sizes;
65
66 rebar_size = i915->params.lmem_bar_size *
67 (resource_size_t)SZ_1M;
68 bar_sizes = pci_rebar_get_possible_sizes(pdev, GEN12_LMEM_BAR);
69
70 if (rebar_size == current_size)
71 return;
72
73 if (!(bar_sizes & BIT(pci_rebar_bytes_to_size(rebar_size))) ||
74 rebar_size >= roundup_pow_of_two(lmem_size)) {
75 rebar_size = lmem_size;
76
77 drm_info(&i915->drm,
78 "Given bar size is not within supported size, setting it to default: %llu\n",
79 (u64)lmem_size >> 20);
80 }
81 } else {
82 rebar_size = current_size;
83
84 if (rebar_size != roundup_pow_of_two(lmem_size))
85 rebar_size = lmem_size;
86 else
87 return;
88 }
89
90 /* Find out if root bus contains 64bit memory addressing */
91 while (root->parent)
92 root = root->parent;
93
94 pci_bus_for_each_resource(root, root_res, i) {
95 if (root_res && root_res->flags & (IORESOURCE_MEM | IORESOURCE_MEM_64) &&
96 root_res->start > 0x100000000ull)
97 break;
98 }
99
100 /* pci_resize_resource will fail anyways */
101 if (!root_res) {
102 drm_info(&i915->drm, "Can't resize LMEM BAR - platform support is missing\n");
103 return;
104 }
105
106 /*
107 * Releasing forcewake during BAR resizing results in later forcewake
108 * ack timeouts and former can happen any time - it is asynchronous.
109 * Grabbing all forcewakes prevents it.
110 */
111 with_intel_runtime_pm(i915->uncore.rpm, wakeref) {
112 intel_uncore_forcewake_get(uncore: &i915->uncore, domains: FORCEWAKE_ALL);
113
114 /* First disable PCI memory decoding references */
115 pci_read_config_dword(dev: pdev, PCI_COMMAND, val: &pci_cmd);
116 pci_write_config_dword(dev: pdev, PCI_COMMAND,
117 val: pci_cmd & ~PCI_COMMAND_MEMORY);
118
119 _resize_bar(i915, GEN12_LMEM_BAR, size: rebar_size);
120
121 pci_assign_unassigned_bus_resources(bus: pdev->bus);
122 pci_write_config_dword(dev: pdev, PCI_COMMAND, val: pci_cmd);
123 intel_uncore_forcewake_put(uncore: &i915->uncore, domains: FORCEWAKE_ALL);
124 }
125}
126#else
127static void i915_resize_lmem_bar(struct drm_i915_private *i915, resource_size_t lmem_size) {}
128#endif
129
130static int
131region_lmem_release(struct intel_memory_region *mem)
132{
133 int ret;
134
135 ret = intel_region_ttm_fini(mem);
136 io_mapping_fini(mapping: &mem->iomap);
137
138 return ret;
139}
140
141static int
142region_lmem_init(struct intel_memory_region *mem)
143{
144 int ret;
145
146 if (!io_mapping_init_wc(iomap: &mem->iomap,
147 base: mem->io.start,
148 size: resource_size(res: &mem->io)))
149 return -EIO;
150
151 ret = intel_region_ttm_init(mem);
152 if (ret)
153 goto out_no_buddy;
154
155 return 0;
156
157out_no_buddy:
158 io_mapping_fini(mapping: &mem->iomap);
159
160 return ret;
161}
162
163static const struct intel_memory_region_ops intel_region_lmem_ops = {
164 .init = region_lmem_init,
165 .release = region_lmem_release,
166 .init_object = __i915_gem_ttm_object_init,
167};
168
169static bool get_legacy_lowmem_region(struct intel_uncore *uncore,
170 u64 *start, u32 *size)
171{
172 if (!IS_DG1(uncore->i915))
173 return false;
174
175 *start = 0;
176 *size = SZ_1M;
177
178 drm_dbg(&uncore->i915->drm, "LMEM: reserved legacy low-memory [0x%llx-0x%llx]\n",
179 *start, *start + *size);
180
181 return true;
182}
183
184static int reserve_lowmem_region(struct intel_uncore *uncore,
185 struct intel_memory_region *mem)
186{
187 u64 reserve_start;
188 u32 reserve_size;
189 int ret;
190
191 if (!get_legacy_lowmem_region(uncore, start: &reserve_start, size: &reserve_size))
192 return 0;
193
194 ret = intel_memory_region_reserve(mem, offset: reserve_start, size: reserve_size);
195 if (ret)
196 drm_err(&uncore->i915->drm, "LMEM: reserving low memory region failed\n");
197
198 return ret;
199}
200
201static struct intel_memory_region *setup_lmem(struct intel_gt *gt)
202{
203 struct drm_i915_private *i915 = gt->i915;
204 struct intel_uncore *uncore = gt->uncore;
205 struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
206 struct intel_memory_region *mem;
207 resource_size_t min_page_size;
208 resource_size_t io_start;
209 resource_size_t io_size;
210 resource_size_t lmem_size;
211 int err;
212
213 if (!IS_DGFX(i915))
214 return ERR_PTR(error: -ENODEV);
215
216 if (!i915_pci_resource_valid(pdev, GEN12_LMEM_BAR))
217 return ERR_PTR(error: -ENXIO);
218
219 if (HAS_FLAT_CCS(i915)) {
220 resource_size_t lmem_range;
221 u64 tile_stolen, flat_ccs_base;
222
223 lmem_range = intel_gt_mcr_read_any(gt: to_gt(i915), XEHP_TILE0_ADDR_RANGE) & 0xFFFF;
224 lmem_size = lmem_range >> XEHP_TILE_LMEM_RANGE_SHIFT;
225 lmem_size *= SZ_1G;
226
227 flat_ccs_base = intel_gt_mcr_read_any(gt, XEHP_FLAT_CCS_BASE_ADDR);
228 flat_ccs_base = (flat_ccs_base >> XEHP_CCS_BASE_SHIFT) * SZ_64K;
229
230 if (GEM_WARN_ON(lmem_size < flat_ccs_base))
231 return ERR_PTR(error: -EIO);
232
233 tile_stolen = lmem_size - flat_ccs_base;
234
235 /* If the FLAT_CCS_BASE_ADDR register is not populated, flag an error */
236 if (tile_stolen == lmem_size)
237 drm_err(&i915->drm,
238 "CCS_BASE_ADDR register did not have expected value\n");
239
240 lmem_size -= tile_stolen;
241 } else {
242 /* Stolen starts from GSMBASE without CCS */
243 lmem_size = intel_uncore_read64(uncore: &i915->uncore, GEN6_GSMBASE);
244 }
245
246 i915_resize_lmem_bar(i915, lmem_size);
247
248 if (i915->params.lmem_size > 0) {
249 lmem_size = min_t(resource_size_t, lmem_size,
250 mul_u32_u32(i915->params.lmem_size, SZ_1M));
251 }
252
253 io_start = pci_resource_start(pdev, GEN12_LMEM_BAR);
254 io_size = min(pci_resource_len(pdev, GEN12_LMEM_BAR), lmem_size);
255 if (!io_size)
256 return ERR_PTR(error: -EIO);
257
258 min_page_size = HAS_64K_PAGES(i915) ? I915_GTT_PAGE_SIZE_64K :
259 I915_GTT_PAGE_SIZE_4K;
260 mem = intel_memory_region_create(i915,
261 start: 0,
262 size: lmem_size,
263 min_page_size,
264 io_start,
265 io_size,
266 type: INTEL_MEMORY_LOCAL,
267 instance: 0,
268 ops: &intel_region_lmem_ops);
269 if (IS_ERR(ptr: mem))
270 return mem;
271
272 err = reserve_lowmem_region(uncore, mem);
273 if (err)
274 goto err_region_put;
275
276 if (io_size < lmem_size)
277 drm_info(&i915->drm, "Using a reduced BAR size of %lluMiB. Consider enabling 'Resizable BAR' or similar, if available in the BIOS.\n",
278 (u64)io_size >> 20);
279
280 return mem;
281
282err_region_put:
283 intel_memory_region_destroy(mem);
284 return ERR_PTR(error: err);
285}
286
287struct intel_memory_region *intel_gt_setup_lmem(struct intel_gt *gt)
288{
289 return setup_lmem(gt);
290}
291

source code of linux/drivers/gpu/drm/i915/gt/intel_region_lmem.c