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 	u32 pci_cmd;
58 	int i;
59 
60 	current_size = roundup_pow_of_two(pci_resource_len(pdev, GEN12_LMEM_BAR));
61 
62 	if (i915->params.lmem_bar_size) {
63 		u32 bar_sizes;
64 
65 		rebar_size = i915->params.lmem_bar_size *
66 			(resource_size_t)SZ_1M;
67 		bar_sizes = pci_rebar_get_possible_sizes(pdev, GEN12_LMEM_BAR);
68 
69 		if (rebar_size == current_size)
70 			return;
71 
72 		if (!(bar_sizes & BIT(pci_rebar_bytes_to_size(rebar_size))) ||
73 		    rebar_size >= roundup_pow_of_two(lmem_size)) {
74 			rebar_size = lmem_size;
75 
76 			drm_info(&i915->drm,
77 				 "Given bar size is not within supported size, setting it to default: %llu\n",
78 				 (u64)lmem_size >> 20);
79 		}
80 	} else {
81 		rebar_size = current_size;
82 
83 		if (rebar_size != roundup_pow_of_two(lmem_size))
84 			rebar_size = lmem_size;
85 		else
86 			return;
87 	}
88 
89 	/* Find out if root bus contains 64bit memory addressing */
90 	while (root->parent)
91 		root = root->parent;
92 
93 	pci_bus_for_each_resource(root, root_res, i) {
94 		if (root_res && root_res->flags & (IORESOURCE_MEM | IORESOURCE_MEM_64) &&
95 		    root_res->start > 0x100000000ull)
96 			break;
97 	}
98 
99 	/* pci_resize_resource will fail anyways */
100 	if (!root_res) {
101 		drm_info(&i915->drm, "Can't resize LMEM BAR - platform support is missing\n");
102 		return;
103 	}
104 
105 	/* First disable PCI memory decoding references */
106 	pci_read_config_dword(pdev, PCI_COMMAND, &pci_cmd);
107 	pci_write_config_dword(pdev, PCI_COMMAND,
108 			       pci_cmd & ~PCI_COMMAND_MEMORY);
109 
110 	_resize_bar(i915, GEN12_LMEM_BAR, rebar_size);
111 
112 	pci_assign_unassigned_bus_resources(pdev->bus);
113 	pci_write_config_dword(pdev, PCI_COMMAND, pci_cmd);
114 }
115 #else
116 static void i915_resize_lmem_bar(struct drm_i915_private *i915, resource_size_t lmem_size) {}
117 #endif
118 
119 static int
120 region_lmem_release(struct intel_memory_region *mem)
121 {
122 	int ret;
123 
124 	ret = intel_region_ttm_fini(mem);
125 	io_mapping_fini(&mem->iomap);
126 
127 	return ret;
128 }
129 
130 static int
131 region_lmem_init(struct intel_memory_region *mem)
132 {
133 	int ret;
134 
135 	if (!io_mapping_init_wc(&mem->iomap,
136 				mem->io_start,
137 				mem->io_size))
138 		return -EIO;
139 
140 	ret = intel_region_ttm_init(mem);
141 	if (ret)
142 		goto out_no_buddy;
143 
144 	return 0;
145 
146 out_no_buddy:
147 	io_mapping_fini(&mem->iomap);
148 
149 	return ret;
150 }
151 
152 static const struct intel_memory_region_ops intel_region_lmem_ops = {
153 	.init = region_lmem_init,
154 	.release = region_lmem_release,
155 	.init_object = __i915_gem_ttm_object_init,
156 };
157 
158 static bool get_legacy_lowmem_region(struct intel_uncore *uncore,
159 				     u64 *start, u32 *size)
160 {
161 	if (!IS_DG1_GRAPHICS_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 min_page_size;
197 	resource_size_t io_start;
198 	resource_size_t io_size;
199 	resource_size_t lmem_size;
200 	int err;
201 
202 	if (!IS_DGFX(i915))
203 		return ERR_PTR(-ENODEV);
204 
205 	if (!i915_pci_resource_valid(pdev, GEN12_LMEM_BAR))
206 		return ERR_PTR(-ENXIO);
207 
208 	if (HAS_FLAT_CCS(i915)) {
209 		resource_size_t lmem_range;
210 		u64 tile_stolen, flat_ccs_base;
211 
212 		lmem_range = intel_gt_mcr_read_any(&i915->gt0, XEHP_TILE0_ADDR_RANGE) & 0xFFFF;
213 		lmem_size = lmem_range >> XEHP_TILE_LMEM_RANGE_SHIFT;
214 		lmem_size *= SZ_1G;
215 
216 		flat_ccs_base = intel_gt_mcr_read_any(gt, XEHP_FLAT_CCS_BASE_ADDR);
217 		flat_ccs_base = (flat_ccs_base >> XEHP_CCS_BASE_SHIFT) * SZ_64K;
218 
219 		if (GEM_WARN_ON(lmem_size < flat_ccs_base))
220 			return ERR_PTR(-EIO);
221 
222 		tile_stolen = lmem_size - flat_ccs_base;
223 
224 		/* If the FLAT_CCS_BASE_ADDR register is not populated, flag an error */
225 		if (tile_stolen == lmem_size)
226 			drm_err(&i915->drm,
227 				"CCS_BASE_ADDR register did not have expected value\n");
228 
229 		lmem_size -= tile_stolen;
230 	} else {
231 		/* Stolen starts from GSMBASE without CCS */
232 		lmem_size = intel_uncore_read64(&i915->uncore, GEN12_GSMBASE);
233 	}
234 
235 	i915_resize_lmem_bar(i915, lmem_size);
236 
237 	if (i915->params.lmem_size > 0) {
238 		lmem_size = min_t(resource_size_t, lmem_size,
239 				  mul_u32_u32(i915->params.lmem_size, SZ_1M));
240 	}
241 
242 	io_start = pci_resource_start(pdev, GEN12_LMEM_BAR);
243 	io_size = min(pci_resource_len(pdev, GEN12_LMEM_BAR), lmem_size);
244 	if (!io_size)
245 		return ERR_PTR(-EIO);
246 
247 	min_page_size = HAS_64K_PAGES(i915) ? I915_GTT_PAGE_SIZE_64K :
248 						I915_GTT_PAGE_SIZE_4K;
249 	mem = intel_memory_region_create(i915,
250 					 0,
251 					 lmem_size,
252 					 min_page_size,
253 					 io_start,
254 					 io_size,
255 					 INTEL_MEMORY_LOCAL,
256 					 0,
257 					 &intel_region_lmem_ops);
258 	if (IS_ERR(mem))
259 		return mem;
260 
261 	err = reserve_lowmem_region(uncore, mem);
262 	if (err)
263 		goto err_region_put;
264 
265 	drm_dbg(&i915->drm, "Local memory: %pR\n", &mem->region);
266 	drm_dbg(&i915->drm, "Local memory IO start: %pa\n",
267 		&mem->io_start);
268 	drm_info(&i915->drm, "Local memory IO size: %pa\n",
269 		 &mem->io_size);
270 	drm_info(&i915->drm, "Local memory available: %pa\n",
271 		 &lmem_size);
272 
273 	if (io_size < lmem_size)
274 		drm_info(&i915->drm, "Using a reduced BAR size of %lluMiB. Consider enabling 'Resizable BAR' or similar, if available in the BIOS.\n",
275 			 (u64)io_size >> 20);
276 
277 	return mem;
278 
279 err_region_put:
280 	intel_memory_region_destroy(mem);
281 	return ERR_PTR(err);
282 }
283 
284 struct intel_memory_region *intel_gt_setup_lmem(struct intel_gt *gt)
285 {
286 	return setup_lmem(gt);
287 }
288