xref: /rk3399_ARM-atf/lib/xlat_tables_v2/xlat_tables_utils.c (revision e7b9886c7cbfac488b766b24379249853f78a040)
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_defs.h>
15 #include <xlat_tables_v2.h>
16 
17 #include "xlat_tables_private.h"
18 
19 #if LOG_LEVEL < LOG_LEVEL_VERBOSE
20 
21 void xlat_mmap_print(__unused const mmap_region_t *mmap)
22 {
23 	/* Empty */
24 }
25 
26 void xlat_tables_print(__unused xlat_ctx_t *ctx)
27 {
28 	/* Empty */
29 }
30 
31 #else /* if LOG_LEVEL >= LOG_LEVEL_VERBOSE */
32 
33 void xlat_mmap_print(const mmap_region_t *mmap)
34 {
35 	tf_printf("mmap:\n");
36 	const mmap_region_t *mm = mmap;
37 
38 	while (mm->size != 0U) {
39 		tf_printf(" VA:0x%lx  PA:0x%llx  size:0x%zx  attr:0x%x "
40 			  "granularity:0x%zx\n", mm->base_va, mm->base_pa,
41 			  mm->size, mm->attr, mm->granularity);
42 		++mm;
43 	};
44 	tf_printf("\n");
45 }
46 
47 /* Print the attributes of the specified block descriptor. */
48 static void xlat_desc_print(const xlat_ctx_t *ctx, uint64_t desc)
49 {
50 	uint64_t mem_type_index = ATTR_INDEX_GET(desc);
51 	int xlat_regime = ctx->xlat_regime;
52 
53 	if (mem_type_index == ATTR_IWBWA_OWBWA_NTR_INDEX) {
54 		tf_printf("MEM");
55 	} else if (mem_type_index == ATTR_NON_CACHEABLE_INDEX) {
56 		tf_printf("NC");
57 	} else {
58 		assert(mem_type_index == ATTR_DEVICE_INDEX);
59 		tf_printf("DEV");
60 	}
61 
62 	if (xlat_regime == EL3_REGIME) {
63 		/* For EL3 only check the AP[2] and XN bits. */
64 		tf_printf(((desc & LOWER_ATTRS(AP_RO)) != 0ULL) ? "-RO" : "-RW");
65 		tf_printf(((desc & UPPER_ATTRS(XN)) != 0ULL) ? "-XN" : "-EXEC");
66 	} else {
67 		assert(xlat_regime == EL1_EL0_REGIME);
68 		/*
69 		 * For EL0 and EL1:
70 		 * - In AArch64 PXN and UXN can be set independently but in
71 		 *   AArch32 there is no UXN (XN affects both privilege levels).
72 		 *   For consistency, we set them simultaneously in both cases.
73 		 * - RO and RW permissions must be the same in EL1 and EL0. If
74 		 *   EL0 can access that memory region, so can EL1, with the
75 		 *   same permissions.
76 		 */
77 #if ENABLE_ASSERTIONS
78 		uint64_t xn_mask = xlat_arch_regime_get_xn_desc(EL1_EL0_REGIME);
79 		uint64_t xn_perm = desc & xn_mask;
80 
81 		assert((xn_perm == xn_mask) || (xn_perm == 0ULL));
82 #endif
83 		tf_printf(((desc & LOWER_ATTRS(AP_RO)) != 0ULL) ? "-RO" : "-RW");
84 		/* Only check one of PXN and UXN, the other one is the same. */
85 		tf_printf(((desc & UPPER_ATTRS(PXN)) != 0ULL) ? "-XN" : "-EXEC");
86 		/*
87 		 * Privileged regions can only be accessed from EL1, user
88 		 * regions can be accessed from EL1 and EL0.
89 		 */
90 		tf_printf(((desc & LOWER_ATTRS(AP_ACCESS_UNPRIVILEGED)) != 0ULL)
91 			  ? "-USER" : "-PRIV");
92 	}
93 
94 	tf_printf(((LOWER_ATTRS(NS) & desc) != 0ULL) ? "-NS" : "-S");
95 }
96 
97 static const char * const level_spacers[] = {
98 	"[LV0] ",
99 	"  [LV1] ",
100 	"    [LV2] ",
101 	"      [LV3] "
102 };
103 
104 static const char *invalid_descriptors_ommited =
105 		"%s(%d invalid descriptors omitted)\n";
106 
107 /*
108  * Recursive function that reads the translation tables passed as an argument
109  * and prints their status.
110  */
111 static void xlat_tables_print_internal(xlat_ctx_t *ctx, uintptr_t table_base_va,
112 		const uint64_t *table_base, unsigned int table_entries,
113 		unsigned int level)
114 {
115 	assert(level <= XLAT_TABLE_LEVEL_MAX);
116 
117 	uint64_t desc;
118 	uintptr_t table_idx_va = table_base_va;
119 	unsigned int table_idx = 0U;
120 	size_t level_size = XLAT_BLOCK_SIZE(level);
121 
122 	/*
123 	 * Keep track of how many invalid descriptors are counted in a row.
124 	 * Whenever multiple invalid descriptors are found, only the first one
125 	 * is printed, and a line is added to inform about how many descriptors
126 	 * have been omitted.
127 	 */
128 	int invalid_row_count = 0;
129 
130 	while (table_idx < table_entries) {
131 
132 		desc = table_base[table_idx];
133 
134 		if ((desc & DESC_MASK) == INVALID_DESC) {
135 
136 			if (invalid_row_count == 0) {
137 				tf_printf("%sVA:0x%lx size:0x%zx\n",
138 					  level_spacers[level],
139 					  table_idx_va, level_size);
140 			}
141 			invalid_row_count++;
142 
143 		} else {
144 
145 			if (invalid_row_count > 1) {
146 				tf_printf(invalid_descriptors_ommited,
147 					  level_spacers[level],
148 					  invalid_row_count - 1);
149 			}
150 			invalid_row_count = 0;
151 
152 			/*
153 			 * Check if this is a table or a block. Tables are only
154 			 * allowed in levels other than 3, but DESC_PAGE has the
155 			 * same value as DESC_TABLE, so we need to check.
156 			 */
157 			if (((desc & DESC_MASK) == TABLE_DESC) &&
158 					(level < XLAT_TABLE_LEVEL_MAX)) {
159 				/*
160 				 * Do not print any PA for a table descriptor,
161 				 * as it doesn't directly map physical memory
162 				 * but instead points to the next translation
163 				 * table in the translation table walk.
164 				 */
165 				tf_printf("%sVA:0x%lx size:0x%zx\n",
166 					  level_spacers[level],
167 					  table_idx_va, level_size);
168 
169 				uintptr_t addr_inner = desc & TABLE_ADDR_MASK;
170 
171 				xlat_tables_print_internal(ctx, table_idx_va,
172 					(uint64_t *)addr_inner,
173 					XLAT_TABLE_ENTRIES, level + 1U);
174 			} else {
175 				tf_printf("%sVA:0x%lx PA:0x%llx size:0x%zx ",
176 					  level_spacers[level],
177 					  table_idx_va,
178 					  (uint64_t)(desc & TABLE_ADDR_MASK),
179 					  level_size);
180 				xlat_desc_print(ctx, desc);
181 				tf_printf("\n");
182 			}
183 		}
184 
185 		table_idx++;
186 		table_idx_va += level_size;
187 	}
188 
189 	if (invalid_row_count > 1) {
190 		tf_printf(invalid_descriptors_ommited,
191 			  level_spacers[level], invalid_row_count - 1);
192 	}
193 }
194 
195 void xlat_tables_print(xlat_ctx_t *ctx)
196 {
197 	const char *xlat_regime_str;
198 	int used_page_tables;
199 
200 	if (ctx->xlat_regime == EL1_EL0_REGIME) {
201 		xlat_regime_str = "1&0";
202 	} else {
203 		assert(ctx->xlat_regime == EL3_REGIME);
204 		xlat_regime_str = "3";
205 	}
206 	VERBOSE("Translation tables state:\n");
207 	VERBOSE("  Xlat regime:     EL%s\n", xlat_regime_str);
208 	VERBOSE("  Max allowed PA:  0x%llx\n", ctx->pa_max_address);
209 	VERBOSE("  Max allowed VA:  0x%lx\n", ctx->va_max_address);
210 	VERBOSE("  Max mapped PA:   0x%llx\n", ctx->max_pa);
211 	VERBOSE("  Max mapped VA:   0x%lx\n", ctx->max_va);
212 
213 	VERBOSE("  Initial lookup level: %u\n", ctx->base_level);
214 	VERBOSE("  Entries @initial lookup level: %u\n",
215 		ctx->base_table_entries);
216 
217 #if PLAT_XLAT_TABLES_DYNAMIC
218 	used_page_tables = 0;
219 	for (int i = 0; i < ctx->tables_num; ++i) {
220 		if (ctx->tables_mapped_regions[i] != 0)
221 			++used_page_tables;
222 	}
223 #else
224 	used_page_tables = ctx->next_table;
225 #endif
226 	VERBOSE("  Used %d sub-tables out of %d (spare: %d)\n",
227 		used_page_tables, ctx->tables_num,
228 		ctx->tables_num - used_page_tables);
229 
230 	xlat_tables_print_internal(ctx, 0U, ctx->base_table,
231 				   ctx->base_table_entries, ctx->base_level);
232 }
233 
234 #endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */
235 
236 /*
237  * Do a translation table walk to find the block or page descriptor that maps
238  * virtual_addr.
239  *
240  * On success, return the address of the descriptor within the translation
241  * table. Its lookup level is stored in '*out_level'.
242  * On error, return NULL.
243  *
244  * xlat_table_base
245  *   Base address for the initial lookup level.
246  * xlat_table_base_entries
247  *   Number of entries in the translation table for the initial lookup level.
248  * virt_addr_space_size
249  *   Size in bytes of the virtual address space.
250  */
251 static uint64_t *find_xlat_table_entry(uintptr_t virtual_addr,
252 				       void *xlat_table_base,
253 				       unsigned int xlat_table_base_entries,
254 				       unsigned long long virt_addr_space_size,
255 				       unsigned int *out_level)
256 {
257 	unsigned int start_level;
258 	uint64_t *table;
259 	unsigned int entries;
260 
261 	start_level = GET_XLAT_TABLE_LEVEL_BASE(virt_addr_space_size);
262 
263 	table = xlat_table_base;
264 	entries = xlat_table_base_entries;
265 
266 	for (unsigned int level = start_level;
267 	     level <= XLAT_TABLE_LEVEL_MAX;
268 	     ++level) {
269 		uint64_t idx, desc, desc_type;
270 
271 		idx = XLAT_TABLE_IDX(virtual_addr, level);
272 		if (idx >= entries) {
273 			WARN("Missing xlat table entry at address 0x%lx\n",
274 			     virtual_addr);
275 			return NULL;
276 		}
277 
278 		desc = table[idx];
279 		desc_type = desc & DESC_MASK;
280 
281 		if (desc_type == INVALID_DESC) {
282 			VERBOSE("Invalid entry (memory not mapped)\n");
283 			return NULL;
284 		}
285 
286 		if (level == XLAT_TABLE_LEVEL_MAX) {
287 			/*
288 			 * Only page descriptors allowed at the final lookup
289 			 * level.
290 			 */
291 			assert(desc_type == PAGE_DESC);
292 			*out_level = level;
293 			return &table[idx];
294 		}
295 
296 		if (desc_type == BLOCK_DESC) {
297 			*out_level = level;
298 			return &table[idx];
299 		}
300 
301 		assert(desc_type == TABLE_DESC);
302 		table = (uint64_t *)(uintptr_t)(desc & TABLE_ADDR_MASK);
303 		entries = XLAT_TABLE_ENTRIES;
304 	}
305 
306 	/*
307 	 * This shouldn't be reached, the translation table walk should end at
308 	 * most at level XLAT_TABLE_LEVEL_MAX and return from inside the loop.
309 	 */
310 	assert(0);
311 
312 	return NULL;
313 }
314 
315 
316 static int get_mem_attributes_internal(const xlat_ctx_t *ctx, uintptr_t base_va,
317 		uint32_t *attributes, uint64_t **table_entry,
318 		unsigned long long *addr_pa, unsigned int *table_level)
319 {
320 	uint64_t *entry;
321 	uint64_t desc;
322 	unsigned int level;
323 	unsigned long long virt_addr_space_size;
324 
325 	/*
326 	 * Sanity-check arguments.
327 	 */
328 	assert(ctx != NULL);
329 	assert(ctx->initialized != 0);
330 	assert((ctx->xlat_regime == EL1_EL0_REGIME) ||
331 	       (ctx->xlat_regime == EL3_REGIME));
332 
333 	virt_addr_space_size = (unsigned long long)ctx->va_max_address + 1ULL;
334 	assert(virt_addr_space_size > 0U);
335 
336 	entry = find_xlat_table_entry(base_va,
337 				ctx->base_table,
338 				ctx->base_table_entries,
339 				virt_addr_space_size,
340 				&level);
341 	if (entry == NULL) {
342 		WARN("Address 0x%lx is not mapped.\n", base_va);
343 		return -EINVAL;
344 	}
345 
346 	if (addr_pa != NULL) {
347 		*addr_pa = *entry & TABLE_ADDR_MASK;
348 	}
349 
350 	if (table_entry != NULL) {
351 		*table_entry = entry;
352 	}
353 
354 	if (table_level != NULL) {
355 		*table_level = level;
356 	}
357 
358 	desc = *entry;
359 
360 #if LOG_LEVEL >= LOG_LEVEL_VERBOSE
361 	VERBOSE("Attributes: ");
362 	xlat_desc_print(ctx, desc);
363 	tf_printf("\n");
364 #endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */
365 
366 	assert(attributes != NULL);
367 	*attributes = 0U;
368 
369 	uint64_t attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;
370 
371 	if (attr_index == ATTR_IWBWA_OWBWA_NTR_INDEX) {
372 		*attributes |= MT_MEMORY;
373 	} else if (attr_index == ATTR_NON_CACHEABLE_INDEX) {
374 		*attributes |= MT_NON_CACHEABLE;
375 	} else {
376 		assert(attr_index == ATTR_DEVICE_INDEX);
377 		*attributes |= MT_DEVICE;
378 	}
379 
380 	uint64_t ap2_bit = (desc >> AP2_SHIFT) & 1U;
381 
382 	if (ap2_bit == AP2_RW)
383 		*attributes |= MT_RW;
384 
385 	if (ctx->xlat_regime == EL1_EL0_REGIME) {
386 		uint64_t ap1_bit = (desc >> AP1_SHIFT) & 1U;
387 
388 		if (ap1_bit == AP1_ACCESS_UNPRIVILEGED)
389 			*attributes |= MT_USER;
390 	}
391 
392 	uint64_t ns_bit = (desc >> NS_SHIFT) & 1U;
393 
394 	if (ns_bit == 1U)
395 		*attributes |= MT_NS;
396 
397 	uint64_t xn_mask = xlat_arch_regime_get_xn_desc(ctx->xlat_regime);
398 
399 	if ((desc & xn_mask) == xn_mask) {
400 		*attributes |= MT_EXECUTE_NEVER;
401 	} else {
402 		assert((desc & xn_mask) == 0U);
403 	}
404 
405 	return 0;
406 }
407 
408 
409 int get_mem_attributes(const xlat_ctx_t *ctx, uintptr_t base_va,
410 		       uint32_t *attributes)
411 {
412 	return get_mem_attributes_internal(ctx, base_va, attributes,
413 					   NULL, NULL, NULL);
414 }
415 
416 
417 int change_mem_attributes(const xlat_ctx_t *ctx,
418 			uintptr_t base_va,
419 			size_t size,
420 			uint32_t attr)
421 {
422 	/* Note: This implementation isn't optimized. */
423 
424 	assert(ctx != NULL);
425 	assert(ctx->initialized != 0);
426 
427 	unsigned long long virt_addr_space_size =
428 		(unsigned long long)ctx->va_max_address + 1U;
429 	assert(virt_addr_space_size > 0U);
430 
431 	if (!IS_PAGE_ALIGNED(base_va)) {
432 		WARN("%s: Address 0x%lx is not aligned on a page boundary.\n",
433 		     __func__, base_va);
434 		return -EINVAL;
435 	}
436 
437 	if (size == 0U) {
438 		WARN("%s: Size is 0.\n", __func__);
439 		return -EINVAL;
440 	}
441 
442 	if ((size % PAGE_SIZE) != 0U) {
443 		WARN("%s: Size 0x%zx is not a multiple of a page size.\n",
444 		     __func__, size);
445 		return -EINVAL;
446 	}
447 
448 	if (((attr & MT_EXECUTE_NEVER) == 0U) && ((attr & MT_RW) != 0U)) {
449 		WARN("%s: Mapping memory as read-write and executable not allowed.\n",
450 		     __func__);
451 		return -EINVAL;
452 	}
453 
454 	size_t pages_count = size / PAGE_SIZE;
455 
456 	VERBOSE("Changing memory attributes of %zu pages starting from address 0x%lx...\n",
457 		pages_count, base_va);
458 
459 	uintptr_t base_va_original = base_va;
460 
461 	/*
462 	 * Sanity checks.
463 	 */
464 	for (size_t i = 0U; i < pages_count; ++i) {
465 		const uint64_t *entry;
466 		uint64_t desc, attr_index;
467 		unsigned int level;
468 
469 		entry = find_xlat_table_entry(base_va,
470 					      ctx->base_table,
471 					      ctx->base_table_entries,
472 					      virt_addr_space_size,
473 					      &level);
474 		if (entry == NULL) {
475 			WARN("Address 0x%lx is not mapped.\n", base_va);
476 			return -EINVAL;
477 		}
478 
479 		desc = *entry;
480 
481 		/*
482 		 * Check that all the required pages are mapped at page
483 		 * granularity.
484 		 */
485 		if (((desc & DESC_MASK) != PAGE_DESC) ||
486 			(level != XLAT_TABLE_LEVEL_MAX)) {
487 			WARN("Address 0x%lx is not mapped at the right granularity.\n",
488 			     base_va);
489 			WARN("Granularity is 0x%llx, should be 0x%x.\n",
490 			     (unsigned long long)XLAT_BLOCK_SIZE(level), PAGE_SIZE);
491 			return -EINVAL;
492 		}
493 
494 		/*
495 		 * If the region type is device, it shouldn't be executable.
496 		 */
497 		attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;
498 		if (attr_index == ATTR_DEVICE_INDEX) {
499 			if ((attr & MT_EXECUTE_NEVER) == 0U) {
500 				WARN("Setting device memory as executable at address 0x%lx.",
501 				     base_va);
502 				return -EINVAL;
503 			}
504 		}
505 
506 		base_va += PAGE_SIZE;
507 	}
508 
509 	/* Restore original value. */
510 	base_va = base_va_original;
511 
512 	for (unsigned int i = 0U; i < pages_count; ++i) {
513 
514 		uint32_t old_attr = 0U, new_attr;
515 		uint64_t *entry = NULL;
516 		unsigned int level = 0U;
517 		unsigned long long addr_pa = 0ULL;
518 
519 		(void) get_mem_attributes_internal(ctx, base_va, &old_attr,
520 					    &entry, &addr_pa, &level);
521 
522 		/*
523 		 * From attr, only MT_RO/MT_RW, MT_EXECUTE/MT_EXECUTE_NEVER and
524 		 * MT_USER/MT_PRIVILEGED are taken into account. Any other
525 		 * information is ignored.
526 		 */
527 
528 		/* Clean the old attributes so that they can be rebuilt. */
529 		new_attr = old_attr & ~(MT_RW | MT_EXECUTE_NEVER | MT_USER);
530 
531 		/*
532 		 * Update attributes, but filter out the ones this function
533 		 * isn't allowed to change.
534 		 */
535 		new_attr |= attr & (MT_RW | MT_EXECUTE_NEVER | MT_USER);
536 
537 		/*
538 		 * The break-before-make sequence requires writing an invalid
539 		 * descriptor and making sure that the system sees the change
540 		 * before writing the new descriptor.
541 		 */
542 		*entry = INVALID_DESC;
543 
544 		/* Invalidate any cached copy of this mapping in the TLBs. */
545 		xlat_arch_tlbi_va(base_va, ctx->xlat_regime);
546 
547 		/* Ensure completion of the invalidation. */
548 		xlat_arch_tlbi_va_sync();
549 
550 		/* Write new descriptor */
551 		*entry = xlat_desc(ctx, new_attr, addr_pa, level);
552 
553 		base_va += PAGE_SIZE;
554 	}
555 
556 	/* Ensure that the last descriptor writen is seen by the system. */
557 	dsbish();
558 
559 	return 0;
560 }
561