xref: /openbsd-src/sys/dev/pci/drm/i915/intel_memory_region.c (revision f327808bd62af73d349febeb7cc1a555012cbf01)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2019 Intel Corporation
4  */
5 
6 #include <linux/prandom.h>
7 
8 #include <uapi/drm/i915_drm.h>
9 
10 #include "intel_memory_region.h"
11 #include "i915_drv.h"
12 #include "i915_ttm_buddy_manager.h"
13 
14 static const struct {
15 	u16 class;
16 	u16 instance;
17 } intel_region_map[] = {
18 	[INTEL_REGION_SMEM] = {
19 		.class = INTEL_MEMORY_SYSTEM,
20 		.instance = 0,
21 	},
22 	[INTEL_REGION_LMEM_0] = {
23 		.class = INTEL_MEMORY_LOCAL,
24 		.instance = 0,
25 	},
26 	[INTEL_REGION_STOLEN_SMEM] = {
27 		.class = INTEL_MEMORY_STOLEN_SYSTEM,
28 		.instance = 0,
29 	},
30 	[INTEL_REGION_STOLEN_LMEM] = {
31 		.class = INTEL_MEMORY_STOLEN_LOCAL,
32 		.instance = 0,
33 	},
34 };
35 
36 static int __iopagetest(struct intel_memory_region *mem,
37 			u8 __iomem *va, int pagesize,
38 			u8 value, resource_size_t offset,
39 			const void *caller)
40 {
41 	int byte = get_random_u32_below(pagesize);
42 	u8 result[3];
43 
44 	memset_io(va, value, pagesize); /* or GPF! */
45 	wmb();
46 
47 	result[0] = ioread8(va);
48 	result[1] = ioread8(va + byte);
49 	result[2] = ioread8(va + pagesize - 1);
50 	if (memchr_inv(result, value, sizeof(result))) {
51 		dev_err(mem->i915->drm.dev,
52 			"Failed to read back from memory region:%pR at [%pa + %pa] for %ps; wrote %x, read (%x, %x, %x)\n",
53 			&mem->region, &mem->io.start, &offset, caller,
54 			value, result[0], result[1], result[2]);
55 		return -EINVAL;
56 	}
57 
58 	return 0;
59 }
60 
61 static int iopagetest(struct intel_memory_region *mem,
62 		      resource_size_t offset,
63 		      const void *caller)
64 {
65 	STUB();
66 	return -ENOSYS;
67 #ifdef notyet
68 	const u8 val[] = { 0x0, 0xa5, 0xc3, 0xf0 };
69 	void __iomem *va;
70 	int err;
71 	int i;
72 
73 	va = ioremap_wc(mem->io.start + offset, PAGE_SIZE);
74 	if (!va) {
75 		dev_err(mem->i915->drm.dev,
76 			"Failed to ioremap memory region [%pa + %pa] for %ps\n",
77 			&mem->io.start, &offset, caller);
78 		return -EFAULT;
79 	}
80 
81 	for (i = 0; i < ARRAY_SIZE(val); i++) {
82 		err = __iopagetest(mem, va, PAGE_SIZE, val[i], offset, caller);
83 		if (err)
84 			break;
85 
86 		err = __iopagetest(mem, va, PAGE_SIZE, ~val[i], offset, caller);
87 		if (err)
88 			break;
89 	}
90 
91 	iounmap(va);
92 	return err;
93 #endif
94 }
95 
96 static resource_size_t random_page(resource_size_t last)
97 {
98 	/* Limited to low 44b (16TiB), but should suffice for a spot check */
99 	return get_random_u32_below(last >> PAGE_SHIFT) << PAGE_SHIFT;
100 }
101 
102 static int iomemtest(struct intel_memory_region *mem,
103 		     bool test_all,
104 		     const void *caller)
105 {
106 	resource_size_t last, page;
107 	int err;
108 
109 	if (resource_size(&mem->io) < PAGE_SIZE)
110 		return 0;
111 
112 	last = resource_size(&mem->io) - PAGE_SIZE;
113 
114 	/*
115 	 * Quick test to check read/write access to the iomap (backing store).
116 	 *
117 	 * Write a byte, read it back. If the iomapping fails, we expect
118 	 * a GPF preventing further execution. If the backing store does not
119 	 * exist, the read back will return garbage. We check a couple of pages,
120 	 * the first and last of the specified region to confirm the backing
121 	 * store + iomap does cover the entire memory region; and we check
122 	 * a random offset within as a quick spot check for bad memory.
123 	 */
124 
125 	if (test_all) {
126 		for (page = 0; page <= last; page += PAGE_SIZE) {
127 			err = iopagetest(mem, page, caller);
128 			if (err)
129 				return err;
130 		}
131 	} else {
132 		err = iopagetest(mem, 0, caller);
133 		if (err)
134 			return err;
135 
136 		err = iopagetest(mem, last, caller);
137 		if (err)
138 			return err;
139 
140 		err = iopagetest(mem, random_page(last), caller);
141 		if (err)
142 			return err;
143 	}
144 
145 	return 0;
146 }
147 
148 struct intel_memory_region *
149 intel_memory_region_lookup(struct drm_i915_private *i915,
150 			   u16 class, u16 instance)
151 {
152 	struct intel_memory_region *mr;
153 	int id;
154 
155 	/* XXX: consider maybe converting to an rb tree at some point */
156 	for_each_memory_region(mr, i915, id) {
157 		if (mr->type == class && mr->instance == instance)
158 			return mr;
159 	}
160 
161 	return NULL;
162 }
163 
164 struct intel_memory_region *
165 intel_memory_region_by_type(struct drm_i915_private *i915,
166 			    enum intel_memory_type mem_type)
167 {
168 	struct intel_memory_region *mr;
169 	int id;
170 
171 	for_each_memory_region(mr, i915, id)
172 		if (mr->type == mem_type)
173 			return mr;
174 
175 	return NULL;
176 }
177 
178 /**
179  * intel_memory_region_reserve - Reserve a memory range
180  * @mem: The region for which we want to reserve a range.
181  * @offset: Start of the range to reserve.
182  * @size: The size of the range to reserve.
183  *
184  * Return: 0 on success, negative error code on failure.
185  */
186 int intel_memory_region_reserve(struct intel_memory_region *mem,
187 				resource_size_t offset,
188 				resource_size_t size)
189 {
190 	struct ttm_resource_manager *man = mem->region_private;
191 
192 	GEM_BUG_ON(mem->is_range_manager);
193 
194 	return i915_ttm_buddy_man_reserve(man, offset, size);
195 }
196 
197 void intel_memory_region_debug(struct intel_memory_region *mr,
198 			       struct drm_printer *printer)
199 {
200 	drm_printf(printer, "%s: ", mr->name);
201 
202 	if (mr->region_private)
203 		ttm_resource_manager_debug(mr->region_private, printer);
204 	else
205 		drm_printf(printer, "total:%pa bytes\n", &mr->total);
206 }
207 
208 static int intel_memory_region_memtest(struct intel_memory_region *mem,
209 				       void *caller)
210 {
211 	struct drm_i915_private *i915 = mem->i915;
212 	int err = 0;
213 
214 	if (!mem->io.start)
215 		return 0;
216 
217 	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM) || i915->params.memtest)
218 		err = iomemtest(mem, i915->params.memtest, caller);
219 
220 	return err;
221 }
222 
223 struct intel_memory_region *
224 intel_memory_region_create(struct drm_i915_private *i915,
225 			   resource_size_t start,
226 			   resource_size_t size,
227 			   resource_size_t min_page_size,
228 			   resource_size_t io_start,
229 			   resource_size_t io_size,
230 			   u16 type,
231 			   u16 instance,
232 			   const struct intel_memory_region_ops *ops)
233 {
234 	struct intel_memory_region *mem;
235 	int err;
236 
237 	mem = kzalloc(sizeof(*mem), GFP_KERNEL);
238 	if (!mem)
239 		return ERR_PTR(-ENOMEM);
240 
241 	mem->i915 = i915;
242 	mem->region = DEFINE_RES_MEM(start, size);
243 	mem->io = DEFINE_RES_MEM(io_start, io_size);
244 	mem->min_page_size = min_page_size;
245 	mem->ops = ops;
246 	mem->total = size;
247 	mem->type = type;
248 	mem->instance = instance;
249 
250 	rw_init(&mem->objects.lock, "memobj");
251 	INIT_LIST_HEAD(&mem->objects.list);
252 
253 	if (ops->init) {
254 		err = ops->init(mem);
255 		if (err)
256 			goto err_free;
257 	}
258 
259 	err = intel_memory_region_memtest(mem, (void *)_RET_IP_);
260 	if (err)
261 		goto err_release;
262 
263 	return mem;
264 
265 err_release:
266 	if (mem->ops->release)
267 		mem->ops->release(mem);
268 err_free:
269 	kfree(mem);
270 	return ERR_PTR(err);
271 }
272 
273 void intel_memory_region_set_name(struct intel_memory_region *mem,
274 				  const char *fmt, ...)
275 {
276 	va_list ap;
277 
278 	va_start(ap, fmt);
279 	vsnprintf(mem->name, sizeof(mem->name), fmt, ap);
280 	va_end(ap);
281 }
282 
283 void intel_memory_region_avail(struct intel_memory_region *mr,
284 			       u64 *avail, u64 *visible_avail)
285 {
286 	if (mr->type == INTEL_MEMORY_LOCAL) {
287 		i915_ttm_buddy_man_avail(mr->region_private,
288 					 avail, visible_avail);
289 		*avail <<= PAGE_SHIFT;
290 		*visible_avail <<= PAGE_SHIFT;
291 	} else {
292 		*avail = mr->total;
293 		*visible_avail = mr->total;
294 	}
295 }
296 
297 void intel_memory_region_destroy(struct intel_memory_region *mem)
298 {
299 	int ret = 0;
300 
301 	if (mem->ops->release)
302 		ret = mem->ops->release(mem);
303 
304 #ifdef notyet
305 	GEM_WARN_ON(!list_empty_careful(&mem->objects.list));
306 #endif
307 	mutex_destroy(&mem->objects.lock);
308 	if (!ret)
309 		kfree(mem);
310 }
311 
312 /* Global memory region registration -- only slight layer inversions! */
313 
314 int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
315 {
316 	int err, i;
317 
318 	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
319 		struct intel_memory_region *mem = ERR_PTR(-ENODEV);
320 		u16 type, instance;
321 
322 		if (!HAS_REGION(i915, BIT(i)))
323 			continue;
324 
325 		type = intel_region_map[i].class;
326 		instance = intel_region_map[i].instance;
327 		switch (type) {
328 		case INTEL_MEMORY_SYSTEM:
329 			if (IS_DGFX(i915))
330 				mem = i915_gem_ttm_system_setup(i915, type,
331 								instance);
332 			else
333 				mem = i915_gem_shmem_setup(i915, type,
334 							   instance);
335 			break;
336 		case INTEL_MEMORY_STOLEN_LOCAL:
337 			mem = i915_gem_stolen_lmem_setup(i915, type, instance);
338 			if (!IS_ERR(mem))
339 				i915->mm.stolen_region = mem;
340 			break;
341 		case INTEL_MEMORY_STOLEN_SYSTEM:
342 			mem = i915_gem_stolen_smem_setup(i915, type, instance);
343 			if (!IS_ERR(mem))
344 				i915->mm.stolen_region = mem;
345 			break;
346 		default:
347 			continue;
348 		}
349 
350 		if (IS_ERR(mem)) {
351 			err = PTR_ERR(mem);
352 			drm_err(&i915->drm,
353 				"Failed to setup region(%d) type=%d\n",
354 				err, type);
355 			goto out_cleanup;
356 		}
357 
358 		mem->id = i;
359 		i915->mm.regions[i] = mem;
360 	}
361 
362 	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
363 		struct intel_memory_region *mem = i915->mm.regions[i];
364 		u64 region_size, io_size;
365 
366 		if (!mem)
367 			continue;
368 
369 		region_size = resource_size(&mem->region) >> 20;
370 		io_size = resource_size(&mem->io) >> 20;
371 
372 		if (resource_size(&mem->io))
373 			drm_dbg(&i915->drm, "Memory region(%d): %s: %llu MiB %pR, io: %llu MiB %pR\n",
374 				mem->id, mem->name, region_size, &mem->region, io_size, &mem->io);
375 		else
376 			drm_dbg(&i915->drm, "Memory region(%d): %s: %llu MiB %pR, io: n/a\n",
377 				mem->id, mem->name, region_size, &mem->region);
378 	}
379 
380 	return 0;
381 
382 out_cleanup:
383 	intel_memory_regions_driver_release(i915);
384 	return err;
385 }
386 
387 void intel_memory_regions_driver_release(struct drm_i915_private *i915)
388 {
389 	int i;
390 
391 	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
392 		struct intel_memory_region *region =
393 			fetch_and_zero(&i915->mm.regions[i]);
394 
395 		if (region)
396 			intel_memory_region_destroy(region);
397 	}
398 }
399 
400 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
401 #include "selftests/intel_memory_region.c"
402 #include "selftests/mock_region.c"
403 #endif
404