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
21 static 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(pdev, resno);
28 	}
29 }
30 
31 static 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(size);
36 	int ret;
37 
38 	_release_bars(pdev);
39 
40 	ret = pci_resize_resource(pdev, resno, 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 
50 static 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(&i915->uncore, FORCEWAKE_ALL);
113 
114 		/* First disable PCI memory decoding references */
115 		pci_read_config_dword(pdev, PCI_COMMAND, &pci_cmd);
116 		pci_write_config_dword(pdev, PCI_COMMAND,
117 				       pci_cmd & ~PCI_COMMAND_MEMORY);
118 
119 		_resize_bar(i915, GEN12_LMEM_BAR, rebar_size);
120 
121 		pci_assign_unassigned_bus_resources(pdev->bus);
122 		pci_write_config_dword(pdev, PCI_COMMAND, pci_cmd);
123 		intel_uncore_forcewake_put(&i915->uncore, FORCEWAKE_ALL);
124 	}
125 }
126 #else
127 static void i915_resize_lmem_bar(struct drm_i915_private *i915, resource_size_t lmem_size) {}
128 #endif
129 
130 static int
131 region_lmem_release(struct intel_memory_region *mem)
132 {
133 	int ret;
134 
135 	ret = intel_region_ttm_fini(mem);
136 	io_mapping_fini(&mem->iomap);
137 
138 	return ret;
139 }
140 
141 static int
142 region_lmem_init(struct intel_memory_region *mem)
143 {
144 	int ret;
145 
146 	if (!io_mapping_init_wc(&mem->iomap,
147 				mem->io_start,
148 				mem->io_size))
149 		return -EIO;
150 
151 	ret = intel_region_ttm_init(mem);
152 	if (ret)
153 		goto out_no_buddy;
154 
155 	return 0;
156 
157 out_no_buddy:
158 	io_mapping_fini(&mem->iomap);
159 
160 	return ret;
161 }
162 
163 static 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 
169 static 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 
184 static 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, &reserve_start, &reserve_size))
192 		return 0;
193 
194 	ret = intel_memory_region_reserve(mem, reserve_start, reserve_size);
195 	if (ret)
196 		drm_err(&uncore->i915->drm, "LMEM: reserving low memory region failed\n");
197 
198 	return ret;
199 }
200 
201 static 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(-ENODEV);
215 
216 	if (!i915_pci_resource_valid(pdev, GEN12_LMEM_BAR))
217 		return ERR_PTR(-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(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(-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(&i915->uncore, GEN12_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(-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 					 0,
262 					 lmem_size,
263 					 min_page_size,
264 					 io_start,
265 					 io_size,
266 					 INTEL_MEMORY_LOCAL,
267 					 0,
268 					 &intel_region_lmem_ops);
269 	if (IS_ERR(mem))
270 		return mem;
271 
272 	err = reserve_lowmem_region(uncore, mem);
273 	if (err)
274 		goto err_region_put;
275 
276 	drm_dbg(&i915->drm, "Local memory: %pR\n", &mem->region);
277 	drm_dbg(&i915->drm, "Local memory IO start: %pa\n",
278 		&mem->io_start);
279 	drm_info(&i915->drm, "Local memory IO size: %pa\n",
280 		 &mem->io_size);
281 	drm_info(&i915->drm, "Local memory available: %pa\n",
282 		 &lmem_size);
283 
284 	if (io_size < lmem_size)
285 		drm_info(&i915->drm, "Using a reduced BAR size of %lluMiB. Consider enabling 'Resizable BAR' or similar, if available in the BIOS.\n",
286 			 (u64)io_size >> 20);
287 
288 	return mem;
289 
290 err_region_put:
291 	intel_memory_region_destroy(mem);
292 	return ERR_PTR(err);
293 }
294 
295 struct intel_memory_region *intel_gt_setup_lmem(struct intel_gt *gt)
296 {
297 	return setup_lmem(gt);
298 }
299