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
 14static 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
 36static 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
 61static 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
 92static 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
 98static 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 (mem->io_size < PAGE_SIZE)
106		return 0;
107
108	last = mem->io_size - 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
144struct intel_memory_region *
145intel_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
160struct intel_memory_region *
161intel_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 */
182int 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
193void 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
204static 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
219static 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
235struct intel_memory_region *
236intel_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_start = io_start;
256	mem->io_size = io_size;
257	mem->min_page_size = min_page_size;
258	mem->ops = ops;
259	mem->total = size;
260	mem->type = type;
261	mem->instance = instance;
262
263	snprintf(mem->uabi_name, sizeof(mem->uabi_name), "%s%u",
264		 region_type_str(type), instance);
265
266	mutex_init(&mem->objects.lock);
267	INIT_LIST_HEAD(&mem->objects.list);
268
269	if (ops->init) {
270		err = ops->init(mem);
271		if (err)
272			goto err_free;
273	}
274
275	err = intel_memory_region_memtest(mem, (void *)_RET_IP_);
276	if (err)
277		goto err_release;
278
279	return mem;
280
281err_release:
282	if (mem->ops->release)
283		mem->ops->release(mem);
284err_free:
285	kfree(mem);
286	return ERR_PTR(err);
287}
288
289void intel_memory_region_set_name(struct intel_memory_region *mem,
290				  const char *fmt, ...)
291{
292	va_list ap;
293
294	va_start(ap, fmt);
295	vsnprintf(mem->name, sizeof(mem->name), fmt, ap);
296	va_end(ap);
297}
298
299void intel_memory_region_avail(struct intel_memory_region *mr,
300			       u64 *avail, u64 *visible_avail)
301{
302	if (mr->type == INTEL_MEMORY_LOCAL) {
303		i915_ttm_buddy_man_avail(mr->region_private,
304					 avail, visible_avail);
305		*avail <<= PAGE_SHIFT;
306		*visible_avail <<= PAGE_SHIFT;
307	} else {
308		*avail = mr->total;
309		*visible_avail = mr->total;
310	}
311}
312
313void intel_memory_region_destroy(struct intel_memory_region *mem)
314{
315	int ret = 0;
316
317	if (mem->ops->release)
318		ret = mem->ops->release(mem);
319
320	GEM_WARN_ON(!list_empty_careful(&mem->objects.list));
321	mutex_destroy(&mem->objects.lock);
322	if (!ret)
323		kfree(mem);
324}
325
326/* Global memory region registration -- only slight layer inversions! */
327
328int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
329{
330	int err, i;
331
332	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
333		struct intel_memory_region *mem = ERR_PTR(-ENODEV);
334		u16 type, instance;
335
336		if (!HAS_REGION(i915, BIT(i)))
337			continue;
338
339		type = intel_region_map[i].class;
340		instance = intel_region_map[i].instance;
341		switch (type) {
342		case INTEL_MEMORY_SYSTEM:
343			if (IS_DGFX(i915))
344				mem = i915_gem_ttm_system_setup(i915, type,
345								instance);
346			else
347				mem = i915_gem_shmem_setup(i915, type,
348							   instance);
349			break;
350		case INTEL_MEMORY_STOLEN_LOCAL:
351			mem = i915_gem_stolen_lmem_setup(i915, type, instance);
352			if (!IS_ERR(mem))
353				i915->mm.stolen_region = mem;
354			break;
355		case INTEL_MEMORY_STOLEN_SYSTEM:
356			mem = i915_gem_stolen_smem_setup(i915, type, instance);
357			if (!IS_ERR(mem))
358				i915->mm.stolen_region = mem;
359			break;
360		default:
361			continue;
362		}
363
364		if (IS_ERR(mem)) {
365			err = PTR_ERR(mem);
366			drm_err(&i915->drm,
367				"Failed to setup region(%d) type=%d\n",
368				err, type);
369			goto out_cleanup;
370		}
371
372		mem->id = i;
373		i915->mm.regions[i] = mem;
374	}
375
376	return 0;
377
378out_cleanup:
379	intel_memory_regions_driver_release(i915);
380	return err;
381}
382
383void intel_memory_regions_driver_release(struct drm_i915_private *i915)
384{
385	int i;
386
387	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
388		struct intel_memory_region *region =
389			fetch_and_zero(&i915->mm.regions[i]);
390
391		if (region)
392			intel_memory_region_destroy(region);
393	}
394}
395
396#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
397#include "selftests/intel_memory_region.c"
398#include "selftests/mock_region.c"
399#endif