xref: /rk3399_ARM-atf/lib/xlat_tables_v2/xlat_tables_utils.c (revision b56dc2a98cab0ea618cce83b3702814b7fcafd7d)
1 /*
2  * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <arch_helpers.h>
8 #include <assert.h>
9 #include <debug.h>
10 #include <errno.h>
11 #include <platform_def.h>
12 #include <types.h>
13 #include <utils_def.h>
14 #include <xlat_tables_arch_private.h>
15 #include <xlat_tables_defs.h>
16 #include <xlat_tables_v2.h>
17 
18 #include "xlat_tables_private.h"
19 
20 #if LOG_LEVEL < LOG_LEVEL_VERBOSE
21 
22 void xlat_mmap_print(__unused mmap_region_t *const mmap)
23 {
24 	/* Empty */
25 }
26 
27 void xlat_tables_print(__unused xlat_ctx_t *ctx)
28 {
29 	/* Empty */
30 }
31 
32 #else /* if LOG_LEVEL >= LOG_LEVEL_VERBOSE */
33 
34 void xlat_mmap_print(mmap_region_t *const mmap)
35 {
36 	tf_printf("mmap:\n");
37 	const mmap_region_t *mm = mmap;
38 
39 	while (mm->size != 0U) {
40 		tf_printf(" VA:0x%lx  PA:0x%llx  size:0x%zx  attr:0x%x "
41 			  "granularity:0x%zx\n", mm->base_va, mm->base_pa,
42 			  mm->size, mm->attr, mm->granularity);
43 		++mm;
44 	};
45 	tf_printf("\n");
46 }
47 
48 /* Print the attributes of the specified block descriptor. */
49 static void xlat_desc_print(const xlat_ctx_t *ctx, uint64_t desc)
50 {
51 	int mem_type_index = ATTR_INDEX_GET(desc);
52 	int xlat_regime = ctx->xlat_regime;
53 
54 	if (mem_type_index == ATTR_IWBWA_OWBWA_NTR_INDEX) {
55 		tf_printf("MEM");
56 	} else if (mem_type_index == ATTR_NON_CACHEABLE_INDEX) {
57 		tf_printf("NC");
58 	} else {
59 		assert(mem_type_index == ATTR_DEVICE_INDEX);
60 		tf_printf("DEV");
61 	}
62 
63 	if (xlat_regime == EL3_REGIME) {
64 		/* For EL3 only check the AP[2] and XN bits. */
65 		tf_printf((desc & LOWER_ATTRS(AP_RO)) ? "-RO" : "-RW");
66 		tf_printf((desc & UPPER_ATTRS(XN)) ? "-XN" : "-EXEC");
67 	} else {
68 		assert(xlat_regime == EL1_EL0_REGIME);
69 		/*
70 		 * For EL0 and EL1:
71 		 * - In AArch64 PXN and UXN can be set independently but in
72 		 *   AArch32 there is no UXN (XN affects both privilege levels).
73 		 *   For consistency, we set them simultaneously in both cases.
74 		 * - RO and RW permissions must be the same in EL1 and EL0. If
75 		 *   EL0 can access that memory region, so can EL1, with the
76 		 *   same permissions.
77 		 */
78 #if ENABLE_ASSERTIONS
79 		uint64_t xn_mask = xlat_arch_regime_get_xn_desc(EL1_EL0_REGIME);
80 		uint64_t xn_perm = desc & xn_mask;
81 
82 		assert((xn_perm == xn_mask) || (xn_perm == 0ULL));
83 #endif
84 		tf_printf((desc & LOWER_ATTRS(AP_RO)) ? "-RO" : "-RW");
85 		/* Only check one of PXN and UXN, the other one is the same. */
86 		tf_printf((desc & UPPER_ATTRS(PXN)) ? "-XN" : "-EXEC");
87 		/*
88 		 * Privileged regions can only be accessed from EL1, user
89 		 * regions can be accessed from EL1 and EL0.
90 		 */
91 		tf_printf((desc & LOWER_ATTRS(AP_ACCESS_UNPRIVILEGED))
92 			  ? "-USER" : "-PRIV");
93 	}
94 
95 	tf_printf(LOWER_ATTRS(NS) & desc ? "-NS" : "-S");
96 }
97 
98 static const char * const level_spacers[] = {
99 	"[LV0] ",
100 	"  [LV1] ",
101 	"    [LV2] ",
102 	"      [LV3] "
103 };
104 
105 static const char *invalid_descriptors_ommited =
106 		"%s(%d invalid descriptors omitted)\n";
107 
108 /*
109  * Recursive function that reads the translation tables passed as an argument
110  * and prints their status.
111  */
112 static void xlat_tables_print_internal(xlat_ctx_t *ctx,
113 		const uintptr_t table_base_va,
114 		uint64_t *const table_base, const int table_entries,
115 		const unsigned int level)
116 {
117 	assert(level <= XLAT_TABLE_LEVEL_MAX);
118 
119 	uint64_t desc;
120 	uintptr_t table_idx_va = table_base_va;
121 	int table_idx = 0;
122 
123 	size_t level_size = XLAT_BLOCK_SIZE(level);
124 
125 	/*
126 	 * Keep track of how many invalid descriptors are counted in a row.
127 	 * Whenever multiple invalid descriptors are found, only the first one
128 	 * is printed, and a line is added to inform about how many descriptors
129 	 * have been omitted.
130 	 */
131 	int invalid_row_count = 0;
132 
133 	while (table_idx < table_entries) {
134 
135 		desc = table_base[table_idx];
136 
137 		if ((desc & DESC_MASK) == INVALID_DESC) {
138 
139 			if (invalid_row_count == 0) {
140 				tf_printf("%sVA:%p size:0x%zx\n",
141 					  level_spacers[level],
142 					  (void *)table_idx_va, level_size);
143 			}
144 			invalid_row_count++;
145 
146 		} else {
147 
148 			if (invalid_row_count > 1) {
149 				tf_printf(invalid_descriptors_ommited,
150 					  level_spacers[level],
151 					  invalid_row_count - 1);
152 			}
153 			invalid_row_count = 0;
154 
155 			/*
156 			 * Check if this is a table or a block. Tables are only
157 			 * allowed in levels other than 3, but DESC_PAGE has the
158 			 * same value as DESC_TABLE, so we need to check.
159 			 */
160 			if (((desc & DESC_MASK) == TABLE_DESC) &&
161 					(level < XLAT_TABLE_LEVEL_MAX)) {
162 				/*
163 				 * Do not print any PA for a table descriptor,
164 				 * as it doesn't directly map physical memory
165 				 * but instead points to the next translation
166 				 * table in the translation table walk.
167 				 */
168 				tf_printf("%sVA:%p size:0x%zx\n",
169 					  level_spacers[level],
170 					  (void *)table_idx_va, level_size);
171 
172 				uintptr_t addr_inner = desc & TABLE_ADDR_MASK;
173 
174 				xlat_tables_print_internal(ctx, table_idx_va,
175 					(uint64_t *)addr_inner,
176 					XLAT_TABLE_ENTRIES, level + 1);
177 			} else {
178 				tf_printf("%sVA:%p PA:0x%llx size:0x%zx ",
179 					  level_spacers[level],
180 					  (void *)table_idx_va,
181 					  (unsigned long long)(desc & TABLE_ADDR_MASK),
182 					  level_size);
183 				xlat_desc_print(ctx, desc);
184 				tf_printf("\n");
185 			}
186 		}
187 
188 		table_idx++;
189 		table_idx_va += level_size;
190 	}
191 
192 	if (invalid_row_count > 1) {
193 		tf_printf(invalid_descriptors_ommited,
194 			  level_spacers[level], invalid_row_count - 1);
195 	}
196 }
197 
198 void xlat_tables_print(xlat_ctx_t *ctx)
199 {
200 	const char *xlat_regime_str;
201 	if (ctx->xlat_regime == EL1_EL0_REGIME) {
202 		xlat_regime_str = "1&0";
203 	} else {
204 		assert(ctx->xlat_regime == EL3_REGIME);
205 		xlat_regime_str = "3";
206 	}
207 	VERBOSE("Translation tables state:\n");
208 	VERBOSE("  Xlat regime:     EL%s\n", xlat_regime_str);
209 	VERBOSE("  Max allowed PA:  0x%llx\n", ctx->pa_max_address);
210 	VERBOSE("  Max allowed VA:  %p\n", (void *) ctx->va_max_address);
211 	VERBOSE("  Max mapped PA:   0x%llx\n", ctx->max_pa);
212 	VERBOSE("  Max mapped VA:   %p\n", (void *) ctx->max_va);
213 
214 	VERBOSE("  Initial lookup level: %i\n", ctx->base_level);
215 	VERBOSE("  Entries @initial lookup level: %i\n",
216 		ctx->base_table_entries);
217 
218 	int used_page_tables;
219 #if PLAT_XLAT_TABLES_DYNAMIC
220 	used_page_tables = 0;
221 	for (unsigned int i = 0; i < ctx->tables_num; ++i) {
222 		if (ctx->tables_mapped_regions[i] != 0)
223 			++used_page_tables;
224 	}
225 #else
226 	used_page_tables = ctx->next_table;
227 #endif
228 	VERBOSE("  Used %i sub-tables out of %i (spare: %i)\n",
229 		used_page_tables, ctx->tables_num,
230 		ctx->tables_num - used_page_tables);
231 
232 	xlat_tables_print_internal(ctx, 0, ctx->base_table,
233 				   ctx->base_table_entries, ctx->base_level);
234 }
235 
236 #endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */
237 
238 /*
239  * Do a translation table walk to find the block or page descriptor that maps
240  * virtual_addr.
241  *
242  * On success, return the address of the descriptor within the translation
243  * table. Its lookup level is stored in '*out_level'.
244  * On error, return NULL.
245  *
246  * xlat_table_base
247  *   Base address for the initial lookup level.
248  * xlat_table_base_entries
249  *   Number of entries in the translation table for the initial lookup level.
250  * virt_addr_space_size
251  *   Size in bytes of the virtual address space.
252  */
253 static uint64_t *find_xlat_table_entry(uintptr_t virtual_addr,
254 				       void *xlat_table_base,
255 				       int xlat_table_base_entries,
256 				       unsigned long long virt_addr_space_size,
257 				       int *out_level)
258 {
259 	unsigned int start_level;
260 	uint64_t *table;
261 	int entries;
262 
263 	start_level = GET_XLAT_TABLE_LEVEL_BASE(virt_addr_space_size);
264 
265 	table = xlat_table_base;
266 	entries = xlat_table_base_entries;
267 
268 	for (unsigned int level = start_level;
269 	     level <= XLAT_TABLE_LEVEL_MAX;
270 	     ++level) {
271 		int idx;
272 		uint64_t desc;
273 		uint64_t desc_type;
274 
275 		idx = XLAT_TABLE_IDX(virtual_addr, level);
276 		if (idx >= entries) {
277 			WARN("Missing xlat table entry at address 0x%lx\n",
278 			     virtual_addr);
279 			return NULL;
280 		}
281 
282 		desc = table[idx];
283 		desc_type = desc & DESC_MASK;
284 
285 		if (desc_type == INVALID_DESC) {
286 			VERBOSE("Invalid entry (memory not mapped)\n");
287 			return NULL;
288 		}
289 
290 		if (level == XLAT_TABLE_LEVEL_MAX) {
291 			/*
292 			 * Only page descriptors allowed at the final lookup
293 			 * level.
294 			 */
295 			assert(desc_type == PAGE_DESC);
296 			*out_level = level;
297 			return &table[idx];
298 		}
299 
300 		if (desc_type == BLOCK_DESC) {
301 			*out_level = level;
302 			return &table[idx];
303 		}
304 
305 		assert(desc_type == TABLE_DESC);
306 		table = (uint64_t *)(uintptr_t)(desc & TABLE_ADDR_MASK);
307 		entries = XLAT_TABLE_ENTRIES;
308 	}
309 
310 	/*
311 	 * This shouldn't be reached, the translation table walk should end at
312 	 * most at level XLAT_TABLE_LEVEL_MAX and return from inside the loop.
313 	 */
314 	assert(0);
315 
316 	return NULL;
317 }
318 
319 
320 static int get_mem_attributes_internal(const xlat_ctx_t *ctx, uintptr_t base_va,
321 		uint32_t *attributes, uint64_t **table_entry,
322 		unsigned long long *addr_pa, int *table_level)
323 {
324 	uint64_t *entry;
325 	uint64_t desc;
326 	int level;
327 	unsigned long long virt_addr_space_size;
328 
329 	/*
330 	 * Sanity-check arguments.
331 	 */
332 	assert(ctx != NULL);
333 	assert(ctx->initialized);
334 	assert(ctx->xlat_regime == EL1_EL0_REGIME || ctx->xlat_regime == EL3_REGIME);
335 
336 	virt_addr_space_size = (unsigned long long)ctx->va_max_address + 1;
337 	assert(virt_addr_space_size > 0);
338 
339 	entry = find_xlat_table_entry(base_va,
340 				ctx->base_table,
341 				ctx->base_table_entries,
342 				virt_addr_space_size,
343 				&level);
344 	if (entry == NULL) {
345 		WARN("Address %p is not mapped.\n", (void *)base_va);
346 		return -EINVAL;
347 	}
348 
349 	if (addr_pa != NULL) {
350 		*addr_pa = *entry & TABLE_ADDR_MASK;
351 	}
352 
353 	if (table_entry != NULL) {
354 		*table_entry = entry;
355 	}
356 
357 	if (table_level != NULL) {
358 		*table_level = level;
359 	}
360 
361 	desc = *entry;
362 
363 #if LOG_LEVEL >= LOG_LEVEL_VERBOSE
364 	VERBOSE("Attributes: ");
365 	xlat_desc_print(ctx, desc);
366 	tf_printf("\n");
367 #endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */
368 
369 	assert(attributes != NULL);
370 	*attributes = 0;
371 
372 	int attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;
373 
374 	if (attr_index == ATTR_IWBWA_OWBWA_NTR_INDEX) {
375 		*attributes |= MT_MEMORY;
376 	} else if (attr_index == ATTR_NON_CACHEABLE_INDEX) {
377 		*attributes |= MT_NON_CACHEABLE;
378 	} else {
379 		assert(attr_index == ATTR_DEVICE_INDEX);
380 		*attributes |= MT_DEVICE;
381 	}
382 
383 	int ap2_bit = (desc >> AP2_SHIFT) & 1;
384 
385 	if (ap2_bit == AP2_RW)
386 		*attributes |= MT_RW;
387 
388 	if (ctx->xlat_regime == EL1_EL0_REGIME) {
389 		int ap1_bit = (desc >> AP1_SHIFT) & 1;
390 		if (ap1_bit == AP1_ACCESS_UNPRIVILEGED)
391 			*attributes |= MT_USER;
392 	}
393 
394 	int ns_bit = (desc >> NS_SHIFT) & 1;
395 
396 	if (ns_bit == 1)
397 		*attributes |= MT_NS;
398 
399 	uint64_t xn_mask = xlat_arch_regime_get_xn_desc(ctx->xlat_regime);
400 
401 	if ((desc & xn_mask) == xn_mask) {
402 		*attributes |= MT_EXECUTE_NEVER;
403 	} else {
404 		assert((desc & xn_mask) == 0);
405 	}
406 
407 	return 0;
408 }
409 
410 
411 int get_mem_attributes(const xlat_ctx_t *ctx, uintptr_t base_va,
412 		       uint32_t *attributes)
413 {
414 	return get_mem_attributes_internal(ctx, base_va, attributes,
415 					   NULL, NULL, NULL);
416 }
417 
418 
419 int change_mem_attributes(xlat_ctx_t *ctx,
420 			uintptr_t base_va,
421 			size_t size,
422 			uint32_t attr)
423 {
424 	/* Note: This implementation isn't optimized. */
425 
426 	assert(ctx != NULL);
427 	assert(ctx->initialized);
428 
429 	unsigned long long virt_addr_space_size =
430 		(unsigned long long)ctx->va_max_address + 1;
431 	assert(virt_addr_space_size > 0);
432 
433 	if (!IS_PAGE_ALIGNED(base_va)) {
434 		WARN("%s: Address %p is not aligned on a page boundary.\n",
435 		     __func__, (void *)base_va);
436 		return -EINVAL;
437 	}
438 
439 	if (size == 0) {
440 		WARN("%s: Size is 0.\n", __func__);
441 		return -EINVAL;
442 	}
443 
444 	if ((size % PAGE_SIZE) != 0) {
445 		WARN("%s: Size 0x%zx is not a multiple of a page size.\n",
446 		     __func__, size);
447 		return -EINVAL;
448 	}
449 
450 	if (((attr & MT_EXECUTE_NEVER) == 0) && ((attr & MT_RW) != 0)) {
451 		WARN("%s: Mapping memory as read-write and executable not allowed.\n",
452 		     __func__);
453 		return -EINVAL;
454 	}
455 
456 	int pages_count = size / PAGE_SIZE;
457 
458 	VERBOSE("Changing memory attributes of %i pages starting from address %p...\n",
459 		pages_count, (void *)base_va);
460 
461 	uintptr_t base_va_original = base_va;
462 
463 	/*
464 	 * Sanity checks.
465 	 */
466 	for (int i = 0; i < pages_count; ++i) {
467 		uint64_t *entry;
468 		uint64_t desc;
469 		int level;
470 
471 		entry = find_xlat_table_entry(base_va,
472 					      ctx->base_table,
473 					      ctx->base_table_entries,
474 					      virt_addr_space_size,
475 					      &level);
476 		if (entry == NULL) {
477 			WARN("Address %p is not mapped.\n", (void *)base_va);
478 			return -EINVAL;
479 		}
480 
481 		desc = *entry;
482 
483 		/*
484 		 * Check that all the required pages are mapped at page
485 		 * granularity.
486 		 */
487 		if (((desc & DESC_MASK) != PAGE_DESC) ||
488 			(level != XLAT_TABLE_LEVEL_MAX)) {
489 			WARN("Address %p is not mapped at the right granularity.\n",
490 			     (void *)base_va);
491 			WARN("Granularity is 0x%llx, should be 0x%x.\n",
492 			     (unsigned long long)XLAT_BLOCK_SIZE(level), PAGE_SIZE);
493 			return -EINVAL;
494 		}
495 
496 		/*
497 		 * If the region type is device, it shouldn't be executable.
498 		 */
499 		int attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;
500 		if (attr_index == ATTR_DEVICE_INDEX) {
501 			if ((attr & MT_EXECUTE_NEVER) == 0) {
502 				WARN("Setting device memory as executable at address %p.",
503 				     (void *)base_va);
504 				return -EINVAL;
505 			}
506 		}
507 
508 		base_va += PAGE_SIZE;
509 	}
510 
511 	/* Restore original value. */
512 	base_va = base_va_original;
513 
514 	for (int i = 0; i < pages_count; ++i) {
515 
516 		uint32_t old_attr, new_attr;
517 		uint64_t *entry;
518 		int level;
519 		unsigned long long addr_pa;
520 
521 		get_mem_attributes_internal(ctx, base_va, &old_attr,
522 					    &entry, &addr_pa, &level);
523 
524 		/*
525 		 * From attr, only MT_RO/MT_RW, MT_EXECUTE/MT_EXECUTE_NEVER and
526 		 * MT_USER/MT_PRIVILEGED are taken into account. Any other
527 		 * information is ignored.
528 		 */
529 
530 		/* Clean the old attributes so that they can be rebuilt. */
531 		new_attr = old_attr & ~(MT_RW | MT_EXECUTE_NEVER | MT_USER);
532 
533 		/*
534 		 * Update attributes, but filter out the ones this function
535 		 * isn't allowed to change.
536 		 */
537 		new_attr |= attr & (MT_RW | MT_EXECUTE_NEVER | MT_USER);
538 
539 		/*
540 		 * The break-before-make sequence requires writing an invalid
541 		 * descriptor and making sure that the system sees the change
542 		 * before writing the new descriptor.
543 		 */
544 		*entry = INVALID_DESC;
545 
546 		/* Invalidate any cached copy of this mapping in the TLBs. */
547 		xlat_arch_tlbi_va_regime(base_va, ctx->xlat_regime);
548 
549 		/* Ensure completion of the invalidation. */
550 		xlat_arch_tlbi_va_sync();
551 
552 		/* Write new descriptor */
553 		*entry = xlat_desc(ctx, new_attr, addr_pa, level);
554 
555 		base_va += PAGE_SIZE;
556 	}
557 
558 	/* Ensure that the last descriptor writen is seen by the system. */
559 	dsbish();
560 
561 	return 0;
562 }
563