1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2019 Intel Corporation
4  */
5 
6 #include "i915_drv.h"
7 #include "i915_reg.h"
8 #include "intel_memory_region.h"
9 #include "intel_region_lmem.h"
10 #include "intel_region_ttm.h"
11 #include "gem/i915_gem_lmem.h"
12 #include "gem/i915_gem_region.h"
13 #include "gem/i915_gem_ttm.h"
14 #include "gt/intel_gt.h"
15 #include "gt/intel_gt_mcr.h"
16 #include "gt/intel_gt_regs.h"
17 
18 static void _release_bars(struct pci_dev *pdev)
19 {
20 	int resno;
21 
22 	for (resno = PCI_STD_RESOURCES; resno < PCI_STD_RESOURCE_END; resno++) {
23 		if (pci_resource_len(pdev, resno))
24 			pci_release_resource(pdev, resno);
25 	}
26 }
27 
28 static void
29 _resize_bar(struct drm_i915_private *i915, int resno, resource_size_t size)
30 {
31 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
32 	int bar_size = pci_rebar_bytes_to_size(size);
33 	int ret;
34 
35 	_release_bars(pdev);
36 
37 	ret = pci_resize_resource(pdev, resno, bar_size);
38 	if (ret) {
39 		drm_info(&i915->drm, "Failed to resize BAR%d to %dM (%pe)\n",
40 			 resno, 1 << bar_size, ERR_PTR(ret));
41 		return;
42 	}
43 
44 	drm_info(&i915->drm, "BAR%d resized to %dM\n", resno, 1 << bar_size);
45 }
46 
47 #define LMEM_BAR_NUM 2
48 static void i915_resize_lmem_bar(struct drm_i915_private *i915, resource_size_t lmem_size)
49 {
50 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
51 	struct pci_bus *root = pdev->bus;
52 	struct resource *root_res;
53 	resource_size_t rebar_size;
54 	resource_size_t current_size;
55 	u32 pci_cmd;
56 	int i;
57 
58 	current_size = roundup_pow_of_two(pci_resource_len(pdev, LMEM_BAR_NUM));
59 
60 	if (i915->params.lmem_bar_size) {
61 		u32 bar_sizes;
62 
63 		rebar_size = i915->params.lmem_bar_size *
64 			(resource_size_t)SZ_1M;
65 		bar_sizes = pci_rebar_get_possible_sizes(pdev,
66 							 LMEM_BAR_NUM);
67 
68 		if (rebar_size == current_size)
69 			return;
70 
71 		if (!(bar_sizes & BIT(pci_rebar_bytes_to_size(rebar_size))) ||
72 		    rebar_size >= roundup_pow_of_two(lmem_size)) {
73 			rebar_size = lmem_size;
74 
75 			drm_info(&i915->drm,
76 				 "Given bar size is not within supported size, setting it to default: %llu\n",
77 				 (u64)lmem_size >> 20);
78 		}
79 	} else {
80 		rebar_size = current_size;
81 
82 		if (rebar_size != roundup_pow_of_two(lmem_size))
83 			rebar_size = lmem_size;
84 		else
85 			return;
86 	}
87 
88 	/* Find out if root bus contains 64bit memory addressing */
89 	while (root->parent)
90 		root = root->parent;
91 
92 	pci_bus_for_each_resource(root, root_res, i) {
93 		if (root_res && root_res->flags & (IORESOURCE_MEM | IORESOURCE_MEM_64) &&
94 		    root_res->start > 0x100000000ull)
95 			break;
96 	}
97 
98 	/* pci_resize_resource will fail anyways */
99 	if (!root_res) {
100 		drm_info(&i915->drm, "Can't resize LMEM BAR - platform support is missing\n");
101 		return;
102 	}
103 
104 	/* First disable PCI memory decoding references */
105 	pci_read_config_dword(pdev, PCI_COMMAND, &pci_cmd);
106 	pci_write_config_dword(pdev, PCI_COMMAND,
107 			       pci_cmd & ~PCI_COMMAND_MEMORY);
108 
109 	_resize_bar(i915, LMEM_BAR_NUM, rebar_size);
110 
111 	pci_assign_unassigned_bus_resources(pdev->bus);
112 	pci_write_config_dword(pdev, PCI_COMMAND, pci_cmd);
113 }
114 
115 static int
116 region_lmem_release(struct intel_memory_region *mem)
117 {
118 	int ret;
119 
120 	ret = intel_region_ttm_fini(mem);
121 	io_mapping_fini(&mem->iomap);
122 
123 	return ret;
124 }
125 
126 static int
127 region_lmem_init(struct intel_memory_region *mem)
128 {
129 	int ret;
130 
131 	if (!io_mapping_init_wc(&mem->iomap,
132 				mem->io_start,
133 				mem->io_size))
134 		return -EIO;
135 
136 	ret = intel_region_ttm_init(mem);
137 	if (ret)
138 		goto out_no_buddy;
139 
140 	return 0;
141 
142 out_no_buddy:
143 	io_mapping_fini(&mem->iomap);
144 
145 	return ret;
146 }
147 
148 static const struct intel_memory_region_ops intel_region_lmem_ops = {
149 	.init = region_lmem_init,
150 	.release = region_lmem_release,
151 	.init_object = __i915_gem_ttm_object_init,
152 };
153 
154 static bool get_legacy_lowmem_region(struct intel_uncore *uncore,
155 				     u64 *start, u32 *size)
156 {
157 	if (!IS_DG1_GRAPHICS_STEP(uncore->i915, STEP_A0, STEP_C0))
158 		return false;
159 
160 	*start = 0;
161 	*size = SZ_1M;
162 
163 	drm_dbg(&uncore->i915->drm, "LMEM: reserved legacy low-memory [0x%llx-0x%llx]\n",
164 		*start, *start + *size);
165 
166 	return true;
167 }
168 
169 static int reserve_lowmem_region(struct intel_uncore *uncore,
170 				 struct intel_memory_region *mem)
171 {
172 	u64 reserve_start;
173 	u32 reserve_size;
174 	int ret;
175 
176 	if (!get_legacy_lowmem_region(uncore, &reserve_start, &reserve_size))
177 		return 0;
178 
179 	ret = intel_memory_region_reserve(mem, reserve_start, reserve_size);
180 	if (ret)
181 		drm_err(&uncore->i915->drm, "LMEM: reserving low memory region failed\n");
182 
183 	return ret;
184 }
185 
186 static struct intel_memory_region *setup_lmem(struct intel_gt *gt)
187 {
188 	struct drm_i915_private *i915 = gt->i915;
189 	struct intel_uncore *uncore = gt->uncore;
190 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
191 	struct intel_memory_region *mem;
192 	resource_size_t min_page_size;
193 	resource_size_t io_start;
194 	resource_size_t io_size;
195 	resource_size_t lmem_size;
196 	int err;
197 
198 	if (!IS_DGFX(i915))
199 		return ERR_PTR(-ENODEV);
200 
201 	if (HAS_FLAT_CCS(i915)) {
202 		resource_size_t lmem_range;
203 		u64 tile_stolen, flat_ccs_base;
204 
205 		lmem_range = intel_gt_mcr_read_any(&i915->gt0, XEHP_TILE0_ADDR_RANGE) & 0xFFFF;
206 		lmem_size = lmem_range >> XEHP_TILE_LMEM_RANGE_SHIFT;
207 		lmem_size *= SZ_1G;
208 
209 		flat_ccs_base = intel_gt_mcr_read_any(gt, XEHP_FLAT_CCS_BASE_ADDR);
210 		flat_ccs_base = (flat_ccs_base >> XEHP_CCS_BASE_SHIFT) * SZ_64K;
211 
212 		if (GEM_WARN_ON(lmem_size < flat_ccs_base))
213 			return ERR_PTR(-EIO);
214 
215 		tile_stolen = lmem_size - flat_ccs_base;
216 
217 		/* If the FLAT_CCS_BASE_ADDR register is not populated, flag an error */
218 		if (tile_stolen == lmem_size)
219 			drm_err(&i915->drm,
220 				"CCS_BASE_ADDR register did not have expected value\n");
221 
222 		lmem_size -= tile_stolen;
223 	} else {
224 		/* Stolen starts from GSMBASE without CCS */
225 		lmem_size = intel_uncore_read64(&i915->uncore, GEN12_GSMBASE);
226 	}
227 
228 	i915_resize_lmem_bar(i915, lmem_size);
229 
230 	if (i915->params.lmem_size > 0) {
231 		lmem_size = min_t(resource_size_t, lmem_size,
232 				  mul_u32_u32(i915->params.lmem_size, SZ_1M));
233 	}
234 
235 	io_start = pci_resource_start(pdev, 2);
236 	io_size = min(pci_resource_len(pdev, 2), lmem_size);
237 	if (!io_size)
238 		return ERR_PTR(-EIO);
239 
240 	min_page_size = HAS_64K_PAGES(i915) ? I915_GTT_PAGE_SIZE_64K :
241 						I915_GTT_PAGE_SIZE_4K;
242 	mem = intel_memory_region_create(i915,
243 					 0,
244 					 lmem_size,
245 					 min_page_size,
246 					 io_start,
247 					 io_size,
248 					 INTEL_MEMORY_LOCAL,
249 					 0,
250 					 &intel_region_lmem_ops);
251 	if (IS_ERR(mem))
252 		return mem;
253 
254 	err = reserve_lowmem_region(uncore, mem);
255 	if (err)
256 		goto err_region_put;
257 
258 	drm_dbg(&i915->drm, "Local memory: %pR\n", &mem->region);
259 	drm_dbg(&i915->drm, "Local memory IO start: %pa\n",
260 		&mem->io_start);
261 	drm_info(&i915->drm, "Local memory IO size: %pa\n",
262 		 &mem->io_size);
263 	drm_info(&i915->drm, "Local memory available: %pa\n",
264 		 &lmem_size);
265 
266 	if (io_size < lmem_size)
267 		drm_info(&i915->drm, "Using a reduced BAR size of %lluMiB. Consider enabling 'Resizable BAR' or similar, if available in the BIOS.\n",
268 			 (u64)io_size >> 20);
269 
270 	return mem;
271 
272 err_region_put:
273 	intel_memory_region_destroy(mem);
274 	return ERR_PTR(err);
275 }
276 
277 struct intel_memory_region *intel_gt_setup_lmem(struct intel_gt *gt)
278 {
279 	return setup_lmem(gt);
280 }
281