xref: /linux/drivers/gpu/drm/i915/intel_memory_region.c (revision f057b57270c2a17d3f45c177e9434fa5745caa48) 
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 	const u8 val[] = { 0x0, 0xa5, 0xc3, 0xf0 };
66 	void __iomem *va;
67 	int err;
68 	int i;
69 
70 	va = ioremap_wc(mem->io.start + offset, PAGE_SIZE);
71 	if (!va) {
72 		dev_err(mem->i915->drm.dev,
73 			"Failed to ioremap memory region [%pa + %pa] for %ps\n",
74 			&mem->io.start, &offset, caller);
75 		return -EFAULT;
76 	}
77 
78 	for (i = 0; i < ARRAY_SIZE(val); i++) {
79 		err = __iopagetest(mem, va, PAGE_SIZE, val[i], offset, caller);
80 		if (err)
81 			break;
82 
83 		err = __iopagetest(mem, va, PAGE_SIZE, ~val[i], offset, caller);
84 		if (err)
85 			break;
86 	}
87 
88 	iounmap(va);
89 	return err;
90 }
91 
92 static resource_size_t random_page(resource_size_t last)
93 {
94 	/* Limited to low 44b (16TiB), but should suffice for a spot check */
95 	return get_random_u32_below(last >> PAGE_SHIFT) << PAGE_SHIFT;
96 }
97 
98 static int iomemtest(struct intel_memory_region *mem,
99 		     bool test_all,
100 		     const void *caller)
101 {
102 	resource_size_t last, page;
103 	int err;
104 
105 	if (resource_size(&mem->io) < PAGE_SIZE)
106 		return 0;
107 
108 	last = resource_size(&mem->io) - PAGE_SIZE;
109 
110 	/*
111 	 * Quick test to check read/write access to the iomap (backing store).
112 	 *
113 	 * Write a byte, read it back. If the iomapping fails, we expect
114 	 * a GPF preventing further execution. If the backing store does not
115 	 * exist, the read back will return garbage. We check a couple of pages,
116 	 * the first and last of the specified region to confirm the backing
117 	 * store + iomap does cover the entire memory region; and we check
118 	 * a random offset within as a quick spot check for bad memory.
119 	 */
120 
121 	if (test_all) {
122 		for (page = 0; page <= last; page += PAGE_SIZE) {
123 			err = iopagetest(mem, page, caller);
124 			if (err)
125 				return err;
126 		}
127 	} else {
128 		err = iopagetest(mem, 0, caller);
129 		if (err)
130 			return err;
131 
132 		err = iopagetest(mem, last, caller);
133 		if (err)
134 			return err;
135 
136 		err = iopagetest(mem, random_page(last), caller);
137 		if (err)
138 			return err;
139 	}
140 
141 	return 0;
142 }
143 
144 struct intel_memory_region *
145 intel_memory_region_lookup(struct drm_i915_private *i915,
146 			   u16 class, u16 instance)
147 {
148 	struct intel_memory_region *mr;
149 	int id;
150 
151 	/* XXX: consider maybe converting to an rb tree at some point */
152 	for_each_memory_region(mr, i915, id) {
153 		if (mr->type == class && mr->instance == instance)
154 			return mr;
155 	}
156 
157 	return NULL;
158 }
159 
160 struct intel_memory_region *
161 intel_memory_region_by_type(struct drm_i915_private *i915,
162 			    enum intel_memory_type mem_type)
163 {
164 	struct intel_memory_region *mr;
165 	int id;
166 
167 	for_each_memory_region(mr, i915, id)
168 		if (mr->type == mem_type)
169 			return mr;
170 
171 	return NULL;
172 }
173 
174 /**
175  * intel_memory_region_reserve - Reserve a memory range
176  * @mem: The region for which we want to reserve a range.
177  * @offset: Start of the range to reserve.
178  * @size: The size of the range to reserve.
179  *
180  * Return: 0 on success, negative error code on failure.
181  */
182 int intel_memory_region_reserve(struct intel_memory_region *mem,
183 				resource_size_t offset,
184 				resource_size_t size)
185 {
186 	struct ttm_resource_manager *man = mem->region_private;
187 
188 	GEM_BUG_ON(mem->is_range_manager);
189 
190 	return i915_ttm_buddy_man_reserve(man, offset, size);
191 }
192 
193 void intel_memory_region_debug(struct intel_memory_region *mr,
194 			       struct drm_printer *printer)
195 {
196 	drm_printf(printer, "%s: ", mr->name);
197 
198 	if (mr->region_private)
199 		ttm_resource_manager_debug(mr->region_private, printer);
200 	else
201 		drm_printf(printer, "total:%pa bytes\n", &mr->total);
202 }
203 
204 static int intel_memory_region_memtest(struct intel_memory_region *mem,
205 				       void *caller)
206 {
207 	struct drm_i915_private *i915 = mem->i915;
208 	int err = 0;
209 
210 	if (!mem->io.start)
211 		return 0;
212 
213 	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM) || i915->params.memtest)
214 		err = iomemtest(mem, i915->params.memtest, caller);
215 
216 	return err;
217 }
218 
219 static const char *region_type_str(u16 type)
220 {
221 	switch (type) {
222 	case INTEL_MEMORY_SYSTEM:
223 		return "system";
224 	case INTEL_MEMORY_LOCAL:
225 		return "local";
226 	case INTEL_MEMORY_STOLEN_LOCAL:
227 		return "stolen-local";
228 	case INTEL_MEMORY_STOLEN_SYSTEM:
229 		return "stolen-system";
230 	default:
231 		return "unknown";
232 	}
233 }
234 
235 struct intel_memory_region *
236 intel_memory_region_create(struct drm_i915_private *i915,
237 			   resource_size_t start,
238 			   resource_size_t size,
239 			   resource_size_t min_page_size,
240 			   resource_size_t io_start,
241 			   resource_size_t io_size,
242 			   u16 type,
243 			   u16 instance,
244 			   const struct intel_memory_region_ops *ops)
245 {
246 	struct intel_memory_region *mem;
247 	int err;
248 
249 	mem = kzalloc(sizeof(*mem), GFP_KERNEL);
250 	if (!mem)
251 		return ERR_PTR(-ENOMEM);
252 
253 	mem->i915 = i915;
254 	mem->region = DEFINE_RES_MEM(start, size);
255 	mem->io = DEFINE_RES_MEM(io_start, io_size);
256 	mem->min_page_size = min_page_size;
257 	mem->ops = ops;
258 	mem->total = size;
259 	mem->type = type;
260 	mem->instance = instance;
261 
262 	snprintf(mem->uabi_name, sizeof(mem->uabi_name), "%s%u",
263 		 region_type_str(type), instance);
264 
265 	mutex_init(&mem->objects.lock);
266 	INIT_LIST_HEAD(&mem->objects.list);
267 
268 	if (ops->init) {
269 		err = ops->init(mem);
270 		if (err)
271 			goto err_free;
272 	}
273 
274 	err = intel_memory_region_memtest(mem, (void *)_RET_IP_);
275 	if (err)
276 		goto err_release;
277 
278 	return mem;
279 
280 err_release:
281 	if (mem->ops->release)
282 		mem->ops->release(mem);
283 err_free:
284 	kfree(mem);
285 	return ERR_PTR(err);
286 }
287 
288 void intel_memory_region_set_name(struct intel_memory_region *mem,
289 				  const char *fmt, ...)
290 {
291 	va_list ap;
292 
293 	va_start(ap, fmt);
294 	vsnprintf(mem->name, sizeof(mem->name), fmt, ap);
295 	va_end(ap);
296 }
297 
298 void intel_memory_region_avail(struct intel_memory_region *mr,
299 			       u64 *avail, u64 *visible_avail)
300 {
301 	if (mr->type == INTEL_MEMORY_LOCAL) {
302 		i915_ttm_buddy_man_avail(mr->region_private,
303 					 avail, visible_avail);
304 		*avail <<= PAGE_SHIFT;
305 		*visible_avail <<= PAGE_SHIFT;
306 	} else {
307 		*avail = mr->total;
308 		*visible_avail = mr->total;
309 	}
310 }
311 
312 void intel_memory_region_destroy(struct intel_memory_region *mem)
313 {
314 	int ret = 0;
315 
316 	if (mem->ops->release)
317 		ret = mem->ops->release(mem);
318 
319 	GEM_WARN_ON(!list_empty_careful(&mem->objects.list));
320 	mutex_destroy(&mem->objects.lock);
321 	if (!ret)
322 		kfree(mem);
323 }
324 
325 /* Global memory region registration -- only slight layer inversions! */
326 
327 int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
328 {
329 	int err, i;
330 
331 	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
332 		struct intel_memory_region *mem = ERR_PTR(-ENODEV);
333 		u16 type, instance;
334 
335 		if (!HAS_REGION(i915, i))
336 			continue;
337 
338 		type = intel_region_map[i].class;
339 		instance = intel_region_map[i].instance;
340 		switch (type) {
341 		case INTEL_MEMORY_SYSTEM:
342 			if (IS_DGFX(i915))
343 				mem = i915_gem_ttm_system_setup(i915, type,
344 								instance);
345 			else
346 				mem = i915_gem_shmem_setup(i915, type,
347 							   instance);
348 			break;
349 		case INTEL_MEMORY_STOLEN_LOCAL:
350 			mem = i915_gem_stolen_lmem_setup(i915, type, instance);
351 			if (!IS_ERR(mem))
352 				i915->mm.stolen_region = mem;
353 			break;
354 		case INTEL_MEMORY_STOLEN_SYSTEM:
355 			mem = i915_gem_stolen_smem_setup(i915, type, instance);
356 			if (!IS_ERR(mem))
357 				i915->mm.stolen_region = mem;
358 			break;
359 		default:
360 			continue;
361 		}
362 
363 		if (IS_ERR(mem)) {
364 			err = PTR_ERR(mem);
365 			drm_err(&i915->drm,
366 				"Failed to setup region(%d) type=%d\n",
367 				err, type);
368 			goto out_cleanup;
369 		}
370 
371 		if (mem) { /* Skip on non-fatal errors */
372 			mem->id = i;
373 			i915->mm.regions[i] = mem;
374 		}
375 	}
376 
377 	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
378 		struct intel_memory_region *mem = i915->mm.regions[i];
379 		u64 region_size, io_size;
380 
381 		if (!mem)
382 			continue;
383 
384 		region_size = resource_size(&mem->region) >> 20;
385 		io_size = resource_size(&mem->io) >> 20;
386 
387 		if (resource_size(&mem->io))
388 			drm_dbg(&i915->drm, "Memory region(%d): %s: %llu MiB %pR, io: %llu MiB %pR\n",
389 				mem->id, mem->name, region_size, &mem->region, io_size, &mem->io);
390 		else
391 			drm_dbg(&i915->drm, "Memory region(%d): %s: %llu MiB %pR, io: n/a\n",
392 				mem->id, mem->name, region_size, &mem->region);
393 	}
394 
395 	return 0;
396 
397 out_cleanup:
398 	intel_memory_regions_driver_release(i915);
399 	return err;
400 }
401 
402 void intel_memory_regions_driver_release(struct drm_i915_private *i915)
403 {
404 	int i;
405 
406 	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
407 		struct intel_memory_region *region =
408 			fetch_and_zero(&i915->mm.regions[i]);
409 
410 		if (region)
411 			intel_memory_region_destroy(region);
412 	}
413 }
414 
415 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
416 #include "selftests/intel_memory_region.c"
417 #include "selftests/mock_region.c"
418 #endif
419