xref: /rk3399_ARM-atf/lib/gpt_rme/gpt_rme.c (revision e40b563e87fd4ff58474a289909a1827c8d2bca7)
1 /*
2  * Copyright (c) 2022, Arm Limited. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <errno.h>
9 #include <inttypes.h>
10 #include <limits.h>
11 #include <stdint.h>
12 
13 #include <arch.h>
14 #include <arch_features.h>
15 #include <arch_helpers.h>
16 #include <common/debug.h>
17 #include "gpt_rme_private.h"
18 #include <lib/gpt_rme/gpt_rme.h>
19 #include <lib/smccc.h>
20 #include <lib/spinlock.h>
21 #include <lib/xlat_tables/xlat_tables_v2.h>
22 
23 #if !ENABLE_RME
24 #error "ENABLE_RME must be enabled to use the GPT library."
25 #endif
26 
27 /*
28  * Lookup T from PPS
29  *
30  *   PPS    Size    T
31  *   0b000  4GB     32
32  *   0b001  64GB    36
33  *   0b010  1TB     40
34  *   0b011  4TB     42
35  *   0b100  16TB    44
36  *   0b101  256TB   48
37  *   0b110  4PB     52
38  *
39  * See section 15.1.27 of the RME specification.
40  */
41 static const gpt_t_val_e gpt_t_lookup[] = {PPS_4GB_T, PPS_64GB_T,
42 					   PPS_1TB_T, PPS_4TB_T,
43 					   PPS_16TB_T, PPS_256TB_T,
44 					   PPS_4PB_T};
45 
46 /*
47  * Lookup P from PGS
48  *
49  *   PGS    Size    P
50  *   0b00   4KB     12
51  *   0b10   16KB    14
52  *   0b01   64KB    16
53  *
54  * Note that pgs=0b10 is 16KB and pgs=0b01 is 64KB, this is not a typo.
55  *
56  * See section 15.1.27 of the RME specification.
57  */
58 static const gpt_p_val_e gpt_p_lookup[] = {PGS_4KB_P, PGS_64KB_P, PGS_16KB_P};
59 
60 /*
61  * This structure contains GPT configuration data.
62  */
63 typedef struct {
64 	uintptr_t plat_gpt_l0_base;
65 	gpccr_pps_e pps;
66 	gpt_t_val_e t;
67 	gpccr_pgs_e pgs;
68 	gpt_p_val_e p;
69 } gpt_config_t;
70 
71 static gpt_config_t gpt_config;
72 
73 /* These variables are used during initialization of the L1 tables. */
74 static unsigned int gpt_next_l1_tbl_idx;
75 static uintptr_t gpt_l1_tbl;
76 
77 /*
78  * This function checks to see if a GPI value is valid.
79  *
80  * These are valid GPI values.
81  *   GPT_GPI_NO_ACCESS   U(0x0)
82  *   GPT_GPI_SECURE      U(0x8)
83  *   GPT_GPI_NS          U(0x9)
84  *   GPT_GPI_ROOT        U(0xA)
85  *   GPT_GPI_REALM       U(0xB)
86  *   GPT_GPI_ANY         U(0xF)
87  *
88  * Parameters
89  *   gpi		GPI to check for validity.
90  *
91  * Return
92  *   true for a valid GPI, false for an invalid one.
93  */
94 static bool gpt_is_gpi_valid(unsigned int gpi)
95 {
96 	if ((gpi == GPT_GPI_NO_ACCESS) || (gpi == GPT_GPI_ANY) ||
97 	    ((gpi >= GPT_GPI_SECURE) && (gpi <= GPT_GPI_REALM))) {
98 		return true;
99 	}
100 	return false;
101 }
102 
103 /*
104  * This function checks to see if two PAS regions overlap.
105  *
106  * Parameters
107  *   base_1: base address of first PAS
108  *   size_1: size of first PAS
109  *   base_2: base address of second PAS
110  *   size_2: size of second PAS
111  *
112  * Return
113  *   True if PAS regions overlap, false if they do not.
114  */
115 static bool gpt_check_pas_overlap(uintptr_t base_1, size_t size_1,
116 				  uintptr_t base_2, size_t size_2)
117 {
118 	if (((base_1 + size_1) > base_2) && ((base_2 + size_2) > base_1)) {
119 		return true;
120 	}
121 	return false;
122 }
123 
124 /*
125  * This helper function checks to see if a PAS region from index 0 to
126  * (pas_idx - 1) occupies the L0 region at index l0_idx in the L0 table.
127  *
128  * Parameters
129  *   l0_idx:      Index of the L0 entry to check
130  *   pas_regions: PAS region array
131  *   pas_idx:     Upper bound of the PAS array index.
132  *
133  * Return
134  *   True if a PAS region occupies the L0 region in question, false if not.
135  */
136 static bool gpt_does_previous_pas_exist_here(unsigned int l0_idx,
137 					     pas_region_t *pas_regions,
138 					     unsigned int pas_idx)
139 {
140 	/* Iterate over PAS regions up to pas_idx. */
141 	for (unsigned int i = 0U; i < pas_idx; i++) {
142 		if (gpt_check_pas_overlap((GPT_L0GPTSZ_ACTUAL_SIZE * l0_idx),
143 		    GPT_L0GPTSZ_ACTUAL_SIZE,
144 		    pas_regions[i].base_pa, pas_regions[i].size)) {
145 			return true;
146 		}
147 	}
148 	return false;
149 }
150 
151 /*
152  * This function iterates over all of the PAS regions and checks them to ensure
153  * proper alignment of base and size, that the GPI is valid, and that no regions
154  * overlap. As a part of the overlap checks, this function checks existing L0
155  * mappings against the new PAS regions in the event that gpt_init_pas_l1_tables
156  * is called multiple times to place L1 tables in different areas of memory. It
157  * also counts the number of L1 tables needed and returns it on success.
158  *
159  * Parameters
160  *   *pas_regions	Pointer to array of PAS region structures.
161  *   pas_region_cnt	Total number of PAS regions in the array.
162  *
163  * Return
164  *   Negative Linux error code in the event of a failure, number of L1 regions
165  *   required when successful.
166  */
167 static int gpt_validate_pas_mappings(pas_region_t *pas_regions,
168 				     unsigned int pas_region_cnt)
169 {
170 	unsigned int idx;
171 	unsigned int l1_cnt = 0U;
172 	unsigned int pas_l1_cnt;
173 	uint64_t *l0_desc = (uint64_t *)gpt_config.plat_gpt_l0_base;
174 
175 	assert(pas_regions != NULL);
176 	assert(pas_region_cnt != 0U);
177 
178 	for (idx = 0U; idx < pas_region_cnt; idx++) {
179 		/* Check for arithmetic overflow in region. */
180 		if ((ULONG_MAX - pas_regions[idx].base_pa) <
181 		    pas_regions[idx].size) {
182 			ERROR("[GPT] Address overflow in PAS[%u]!\n", idx);
183 			return -EOVERFLOW;
184 		}
185 
186 		/* Initial checks for PAS validity. */
187 		if (((pas_regions[idx].base_pa + pas_regions[idx].size) >
188 		    GPT_PPS_ACTUAL_SIZE(gpt_config.t)) ||
189 		    !gpt_is_gpi_valid(GPT_PAS_ATTR_GPI(pas_regions[idx].attrs))) {
190 			ERROR("[GPT] PAS[%u] is invalid!\n", idx);
191 			return -EFAULT;
192 		}
193 
194 		/*
195 		 * Make sure this PAS does not overlap with another one. We
196 		 * start from idx + 1 instead of 0 since prior PAS mappings will
197 		 * have already checked themselves against this one.
198 		 */
199 		for (unsigned int i = idx + 1; i < pas_region_cnt; i++) {
200 			if (gpt_check_pas_overlap(pas_regions[idx].base_pa,
201 			    pas_regions[idx].size,
202 			    pas_regions[i].base_pa,
203 			    pas_regions[i].size)) {
204 				ERROR("[GPT] PAS[%u] overlaps with PAS[%u]\n",
205 					i, idx);
206 				return -EFAULT;
207 			}
208 		}
209 
210 		/*
211 		 * Since this function can be called multiple times with
212 		 * separate L1 tables we need to check the existing L0 mapping
213 		 * to see if this PAS would fall into one that has already been
214 		 * initialized.
215 		 */
216 		for (unsigned int i = GPT_L0_IDX(pas_regions[idx].base_pa);
217 		     i <= GPT_L0_IDX(pas_regions[idx].base_pa + pas_regions[idx].size - 1);
218 		     i++) {
219 			if ((GPT_L0_TYPE(l0_desc[i]) == GPT_L0_TYPE_BLK_DESC) &&
220 			    (GPT_L0_BLKD_GPI(l0_desc[i]) == GPT_GPI_ANY)) {
221 				/* This descriptor is unused so continue. */
222 				continue;
223 			}
224 
225 			/*
226 			 * This descriptor has been initialized in a previous
227 			 * call to this function so cannot be initialized again.
228 			 */
229 			ERROR("[GPT] PAS[%u] overlaps with previous L0[%d]!\n",
230 			      idx, i);
231 			return -EFAULT;
232 		}
233 
234 		/* Check for block mapping (L0) type. */
235 		if (GPT_PAS_ATTR_MAP_TYPE(pas_regions[idx].attrs) ==
236 		    GPT_PAS_ATTR_MAP_TYPE_BLOCK) {
237 			/* Make sure base and size are block-aligned. */
238 			if (!GPT_IS_L0_ALIGNED(pas_regions[idx].base_pa) ||
239 			    !GPT_IS_L0_ALIGNED(pas_regions[idx].size)) {
240 				ERROR("[GPT] PAS[%u] is not block-aligned!\n",
241 				      idx);
242 				return -EFAULT;
243 			}
244 
245 			continue;
246 		}
247 
248 		/* Check for granule mapping (L1) type. */
249 		if (GPT_PAS_ATTR_MAP_TYPE(pas_regions[idx].attrs) ==
250 		    GPT_PAS_ATTR_MAP_TYPE_GRANULE) {
251 			/* Make sure base and size are granule-aligned. */
252 			if (!GPT_IS_L1_ALIGNED(gpt_config.p, pas_regions[idx].base_pa) ||
253 			    !GPT_IS_L1_ALIGNED(gpt_config.p, pas_regions[idx].size)) {
254 				ERROR("[GPT] PAS[%u] is not granule-aligned!\n",
255 				      idx);
256 				return -EFAULT;
257 			}
258 
259 			/* Find how many L1 tables this PAS occupies. */
260 			pas_l1_cnt = (GPT_L0_IDX(pas_regions[idx].base_pa +
261 				     pas_regions[idx].size - 1) -
262 				     GPT_L0_IDX(pas_regions[idx].base_pa) + 1);
263 
264 			/*
265 			 * This creates a situation where, if multiple PAS
266 			 * regions occupy the same table descriptor, we can get
267 			 * an artificially high total L1 table count. The way we
268 			 * handle this is by checking each PAS against those
269 			 * before it in the array, and if they both occupy the
270 			 * same PAS we subtract from pas_l1_cnt and only the
271 			 * first PAS in the array gets to count it.
272 			 */
273 
274 			/*
275 			 * If L1 count is greater than 1 we know the start and
276 			 * end PAs are in different L0 regions so we must check
277 			 * both for overlap against other PAS.
278 			 */
279 			if (pas_l1_cnt > 1) {
280 				if (gpt_does_previous_pas_exist_here(
281 				    GPT_L0_IDX(pas_regions[idx].base_pa +
282 				    pas_regions[idx].size - 1),
283 				    pas_regions, idx)) {
284 					pas_l1_cnt = pas_l1_cnt - 1;
285 				}
286 			}
287 
288 			if (gpt_does_previous_pas_exist_here(
289 			    GPT_L0_IDX(pas_regions[idx].base_pa),
290 			    pas_regions, idx)) {
291 				pas_l1_cnt = pas_l1_cnt - 1;
292 			}
293 
294 			l1_cnt += pas_l1_cnt;
295 			continue;
296 		}
297 
298 		/* If execution reaches this point, mapping type is invalid. */
299 		ERROR("[GPT] PAS[%u] has invalid mapping type 0x%x.\n", idx,
300 		      GPT_PAS_ATTR_MAP_TYPE(pas_regions[idx].attrs));
301 		return -EINVAL;
302 	}
303 
304 	return l1_cnt;
305 }
306 
307 /*
308  * This function validates L0 initialization parameters.
309  *
310  * Parameters
311  *   l0_mem_base	Base address of memory used for L0 tables.
312  *   l1_mem_size	Size of memory available for L0 tables.
313  *
314  * Return
315  *   Negative Linux error code in the event of a failure, 0 for success.
316  */
317 static int gpt_validate_l0_params(gpccr_pps_e pps, uintptr_t l0_mem_base,
318 				  size_t l0_mem_size)
319 {
320 	size_t l0_alignment;
321 
322 	/*
323 	 * Make sure PPS is valid and then store it since macros need this value
324 	 * to work.
325 	 */
326 	if (pps > GPT_PPS_MAX) {
327 		ERROR("[GPT] Invalid PPS: 0x%x\n", pps);
328 		return -EINVAL;
329 	}
330 	gpt_config.pps = pps;
331 	gpt_config.t = gpt_t_lookup[pps];
332 
333 	/* Alignment must be the greater of 4k or l0 table size. */
334 	l0_alignment = PAGE_SIZE_4KB;
335 	if (l0_alignment < GPT_L0_TABLE_SIZE(gpt_config.t)) {
336 		l0_alignment = GPT_L0_TABLE_SIZE(gpt_config.t);
337 	}
338 
339 	/* Check base address. */
340 	if ((l0_mem_base == 0U) || ((l0_mem_base & (l0_alignment - 1)) != 0U)) {
341 		ERROR("[GPT] Invalid L0 base address: 0x%lx\n", l0_mem_base);
342 		return -EFAULT;
343 	}
344 
345 	/* Check size. */
346 	if (l0_mem_size < GPT_L0_TABLE_SIZE(gpt_config.t)) {
347 		ERROR("[GPT] Inadequate L0 memory: need 0x%lx, have 0x%lx)\n",
348 		      GPT_L0_TABLE_SIZE(gpt_config.t),
349 		      l0_mem_size);
350 		return -ENOMEM;
351 	}
352 
353 	return 0;
354 }
355 
356 /*
357  * In the event that L1 tables are needed, this function validates
358  * the L1 table generation parameters.
359  *
360  * Parameters
361  *   l1_mem_base	Base address of memory used for L1 table allocation.
362  *   l1_mem_size	Total size of memory available for L1 tables.
363  *   l1_gpt_cnt		Number of L1 tables needed.
364  *
365  * Return
366  *   Negative Linux error code in the event of a failure, 0 for success.
367  */
368 static int gpt_validate_l1_params(uintptr_t l1_mem_base, size_t l1_mem_size,
369 				  unsigned int l1_gpt_cnt)
370 {
371 	size_t l1_gpt_mem_sz;
372 
373 	/* Check if the granularity is supported */
374 	if (!xlat_arch_is_granule_size_supported(
375 	    GPT_PGS_ACTUAL_SIZE(gpt_config.p))) {
376 		return -EPERM;
377 	}
378 
379 	/* Make sure L1 tables are aligned to their size. */
380 	if ((l1_mem_base & (GPT_L1_TABLE_SIZE(gpt_config.p) - 1)) != 0U) {
381 		ERROR("[GPT] Unaligned L1 GPT base address: 0x%lx\n",
382 		      l1_mem_base);
383 		return -EFAULT;
384 	}
385 
386 	/* Get total memory needed for L1 tables. */
387 	l1_gpt_mem_sz = l1_gpt_cnt * GPT_L1_TABLE_SIZE(gpt_config.p);
388 
389 	/* Check for overflow. */
390 	if ((l1_gpt_mem_sz / GPT_L1_TABLE_SIZE(gpt_config.p)) != l1_gpt_cnt) {
391 		ERROR("[GPT] Overflow calculating L1 memory size.\n");
392 		return -ENOMEM;
393 	}
394 
395 	/* Make sure enough space was supplied. */
396 	if (l1_mem_size < l1_gpt_mem_sz) {
397 		ERROR("[GPT] Inadequate memory for L1 GPTs. ");
398 		ERROR("      Expected 0x%lx bytes. Got 0x%lx bytes\n",
399 		      l1_gpt_mem_sz, l1_mem_size);
400 		return -ENOMEM;
401 	}
402 
403 	VERBOSE("[GPT] Requested 0x%lx bytes for L1 GPTs.\n", l1_gpt_mem_sz);
404 	return 0;
405 }
406 
407 /*
408  * This function initializes L0 block descriptors (regions that cannot be
409  * transitioned at the granule level) according to the provided PAS.
410  *
411  * Parameters
412  *   *pas		Pointer to the structure defining the PAS region to
413  *			initialize.
414  */
415 static void gpt_generate_l0_blk_desc(pas_region_t *pas)
416 {
417 	uint64_t gpt_desc;
418 	unsigned int end_idx;
419 	unsigned int idx;
420 	uint64_t *l0_gpt_arr;
421 
422 	assert(gpt_config.plat_gpt_l0_base != 0U);
423 	assert(pas != NULL);
424 
425 	/*
426 	 * Checking of PAS parameters has already been done in
427 	 * gpt_validate_pas_mappings so no need to check the same things again.
428 	 */
429 
430 	l0_gpt_arr = (uint64_t *)gpt_config.plat_gpt_l0_base;
431 
432 	/* Create the GPT Block descriptor for this PAS region */
433 	gpt_desc = GPT_L0_BLK_DESC(GPT_PAS_ATTR_GPI(pas->attrs));
434 
435 	/* Start index of this region in L0 GPTs */
436 	idx = GPT_L0_IDX(pas->base_pa);
437 
438 	/*
439 	 * Determine number of L0 GPT descriptors covered by
440 	 * this PAS region and use the count to populate these
441 	 * descriptors.
442 	 */
443 	end_idx = GPT_L0_IDX(pas->base_pa + pas->size);
444 
445 	/* Generate the needed block descriptors. */
446 	for (; idx < end_idx; idx++) {
447 		l0_gpt_arr[idx] = gpt_desc;
448 		VERBOSE("[GPT] L0 entry (BLOCK) index %u [%p]: GPI = 0x%" PRIx64 " (0x%" PRIx64 ")\n",
449 			idx, &l0_gpt_arr[idx],
450 			(gpt_desc >> GPT_L0_BLK_DESC_GPI_SHIFT) &
451 			GPT_L0_BLK_DESC_GPI_MASK, l0_gpt_arr[idx]);
452 	}
453 }
454 
455 /*
456  * Helper function to determine if the end physical address lies in the same L0
457  * region as the current physical address. If true, the end physical address is
458  * returned else, the start address of the next region is returned.
459  *
460  * Parameters
461  *   cur_pa		Physical address of the current PA in the loop through
462  *			the range.
463  *   end_pa		Physical address of the end PA in a PAS range.
464  *
465  * Return
466  *   The PA of the end of the current range.
467  */
468 static uintptr_t gpt_get_l1_end_pa(uintptr_t cur_pa, uintptr_t end_pa)
469 {
470 	uintptr_t cur_idx;
471 	uintptr_t end_idx;
472 
473 	cur_idx = GPT_L0_IDX(cur_pa);
474 	end_idx = GPT_L0_IDX(end_pa);
475 
476 	assert(cur_idx <= end_idx);
477 
478 	if (cur_idx == end_idx) {
479 		return end_pa;
480 	}
481 
482 	return (cur_idx + 1U) << GPT_L0_IDX_SHIFT;
483 }
484 
485 /*
486  * Helper function to fill out GPI entries in a single L1 table. This function
487  * fills out entire L1 descriptors at a time to save memory writes.
488  *
489  * Parameters
490  *   gpi		GPI to set this range to
491  *   l1			Pointer to L1 table to fill out
492  *   first		Address of first granule in range.
493  *   last		Address of last granule in range (inclusive).
494  */
495 static void gpt_fill_l1_tbl(uint64_t gpi, uint64_t *l1, uintptr_t first,
496 			    uintptr_t last)
497 {
498 	uint64_t gpi_field = GPT_BUILD_L1_DESC(gpi);
499 	uint64_t gpi_mask = 0xFFFFFFFFFFFFFFFF;
500 
501 	assert(first <= last);
502 	assert((first & (GPT_PGS_ACTUAL_SIZE(gpt_config.p) - 1)) == 0U);
503 	assert((last & (GPT_PGS_ACTUAL_SIZE(gpt_config.p) - 1)) == 0U);
504 	assert(GPT_L0_IDX(first) == GPT_L0_IDX(last));
505 	assert(l1 != NULL);
506 
507 	/* Shift the mask if we're starting in the middle of an L1 entry. */
508 	gpi_mask = gpi_mask << (GPT_L1_GPI_IDX(gpt_config.p, first) << 2);
509 
510 	/* Fill out each L1 entry for this region. */
511 	for (unsigned int i = GPT_L1_IDX(gpt_config.p, first);
512 	     i <= GPT_L1_IDX(gpt_config.p, last); i++) {
513 		/* Account for stopping in the middle of an L1 entry. */
514 		if (i == GPT_L1_IDX(gpt_config.p, last)) {
515 			gpi_mask &= (gpi_mask >> ((15 -
516 				    GPT_L1_GPI_IDX(gpt_config.p, last)) << 2));
517 		}
518 
519 		/* Write GPI values. */
520 		assert((l1[i] & gpi_mask) ==
521 		       (GPT_BUILD_L1_DESC(GPT_GPI_ANY) & gpi_mask));
522 		l1[i] = (l1[i] & ~gpi_mask) | (gpi_mask & gpi_field);
523 
524 		/* Reset mask. */
525 		gpi_mask = 0xFFFFFFFFFFFFFFFF;
526 	}
527 }
528 
529 /*
530  * This function finds the next available unused L1 table and initializes all
531  * granules descriptor entries to GPI_ANY. This ensures that there are no chunks
532  * of GPI_NO_ACCESS (0b0000) memory floating around in the system in the
533  * event that a PAS region stops midway through an L1 table, thus guaranteeing
534  * that all memory not explicitly assigned is GPI_ANY. This function does not
535  * check for overflow conditions, that should be done by the caller.
536  *
537  * Return
538  *   Pointer to the next available L1 table.
539  */
540 static uint64_t *gpt_get_new_l1_tbl(void)
541 {
542 	/* Retrieve the next L1 table. */
543 	uint64_t *l1 = (uint64_t *)((uint64_t)(gpt_l1_tbl) +
544 		       (GPT_L1_TABLE_SIZE(gpt_config.p) *
545 		       gpt_next_l1_tbl_idx));
546 
547 	/* Increment L1 counter. */
548 	gpt_next_l1_tbl_idx++;
549 
550 	/* Initialize all GPIs to GPT_GPI_ANY */
551 	for (unsigned int i = 0U; i < GPT_L1_ENTRY_COUNT(gpt_config.p); i++) {
552 		l1[i] = GPT_BUILD_L1_DESC(GPT_GPI_ANY);
553 	}
554 
555 	return l1;
556 }
557 
558 /*
559  * When L1 tables are needed, this function creates the necessary L0 table
560  * descriptors and fills out the L1 table entries according to the supplied
561  * PAS range.
562  *
563  * Parameters
564  *   *pas		Pointer to the structure defining the PAS region.
565  */
566 static void gpt_generate_l0_tbl_desc(pas_region_t *pas)
567 {
568 	uintptr_t end_pa;
569 	uintptr_t cur_pa;
570 	uintptr_t last_gran_pa;
571 	uint64_t *l0_gpt_base;
572 	uint64_t *l1_gpt_arr;
573 	unsigned int l0_idx;
574 
575 	assert(gpt_config.plat_gpt_l0_base != 0U);
576 	assert(pas != NULL);
577 
578 	/*
579 	 * Checking of PAS parameters has already been done in
580 	 * gpt_validate_pas_mappings so no need to check the same things again.
581 	 */
582 
583 	end_pa = pas->base_pa + pas->size;
584 	l0_gpt_base = (uint64_t *)gpt_config.plat_gpt_l0_base;
585 
586 	/* We start working from the granule at base PA */
587 	cur_pa = pas->base_pa;
588 
589 	/* Iterate over each L0 region in this memory range. */
590 	for (l0_idx = GPT_L0_IDX(pas->base_pa);
591 	     l0_idx <= GPT_L0_IDX(end_pa - 1U);
592 	     l0_idx++) {
593 
594 		/*
595 		 * See if the L0 entry is already a table descriptor or if we
596 		 * need to create one.
597 		 */
598 		if (GPT_L0_TYPE(l0_gpt_base[l0_idx]) == GPT_L0_TYPE_TBL_DESC) {
599 			/* Get the L1 array from the L0 entry. */
600 			l1_gpt_arr = GPT_L0_TBLD_ADDR(l0_gpt_base[l0_idx]);
601 		} else {
602 			/* Get a new L1 table from the L1 memory space. */
603 			l1_gpt_arr = gpt_get_new_l1_tbl();
604 
605 			/* Fill out the L0 descriptor and flush it. */
606 			l0_gpt_base[l0_idx] = GPT_L0_TBL_DESC(l1_gpt_arr);
607 		}
608 
609 		VERBOSE("[GPT] L0 entry (TABLE) index %u [%p] ==> L1 Addr 0x%llx (0x%" PRIx64 ")\n",
610 			l0_idx, &l0_gpt_base[l0_idx],
611 			(unsigned long long)(l1_gpt_arr),
612 			l0_gpt_base[l0_idx]);
613 
614 		/*
615 		 * Determine the PA of the last granule in this L0 descriptor.
616 		 */
617 		last_gran_pa = gpt_get_l1_end_pa(cur_pa, end_pa) -
618 			       GPT_PGS_ACTUAL_SIZE(gpt_config.p);
619 
620 		/*
621 		 * Fill up L1 GPT entries between these two addresses. This
622 		 * function needs the addresses of the first granule and last
623 		 * granule in the range.
624 		 */
625 		gpt_fill_l1_tbl(GPT_PAS_ATTR_GPI(pas->attrs), l1_gpt_arr,
626 				cur_pa, last_gran_pa);
627 
628 		/* Advance cur_pa to first granule in next L0 region. */
629 		cur_pa = gpt_get_l1_end_pa(cur_pa, end_pa);
630 	}
631 }
632 
633 /*
634  * This function flushes a range of L0 descriptors used by a given PAS region
635  * array. There is a chance that some unmodified L0 descriptors would be flushed
636  * in the case that there are "holes" in an array of PAS regions but overall
637  * this should be faster than individually flushing each modified L0 descriptor
638  * as they are created.
639  *
640  * Parameters
641  *   *pas		Pointer to an array of PAS regions.
642  *   pas_count		Number of entries in the PAS array.
643  */
644 static void flush_l0_for_pas_array(pas_region_t *pas, unsigned int pas_count)
645 {
646 	unsigned int idx;
647 	unsigned int start_idx;
648 	unsigned int end_idx;
649 	uint64_t *l0 = (uint64_t *)gpt_config.plat_gpt_l0_base;
650 
651 	assert(pas != NULL);
652 	assert(pas_count > 0);
653 
654 	/* Initial start and end values. */
655 	start_idx = GPT_L0_IDX(pas[0].base_pa);
656 	end_idx = GPT_L0_IDX(pas[0].base_pa + pas[0].size - 1);
657 
658 	/* Find lowest and highest L0 indices used in this PAS array. */
659 	for (idx = 1; idx < pas_count; idx++) {
660 		if (GPT_L0_IDX(pas[idx].base_pa) < start_idx) {
661 			start_idx = GPT_L0_IDX(pas[idx].base_pa);
662 		}
663 		if (GPT_L0_IDX(pas[idx].base_pa + pas[idx].size - 1) > end_idx) {
664 			end_idx = GPT_L0_IDX(pas[idx].base_pa + pas[idx].size - 1);
665 		}
666 	}
667 
668 	/*
669 	 * Flush all covered L0 descriptors, add 1 because we need to include
670 	 * the end index value.
671 	 */
672 	flush_dcache_range((uintptr_t)&l0[start_idx],
673 			   ((end_idx + 1) - start_idx) * sizeof(uint64_t));
674 }
675 
676 /*
677  * Public API to enable granule protection checks once the tables have all been
678  * initialized. This function is called at first initialization and then again
679  * later during warm boots of CPU cores.
680  *
681  * Return
682  *   Negative Linux error code in the event of a failure, 0 for success.
683  */
684 int gpt_enable(void)
685 {
686 	u_register_t gpccr_el3;
687 
688 	/*
689 	 * Granule tables must be initialised before enabling
690 	 * granule protection.
691 	 */
692 	if (gpt_config.plat_gpt_l0_base == 0U) {
693 		ERROR("[GPT] Tables have not been initialized!\n");
694 		return -EPERM;
695 	}
696 
697 	/* Write the base address of the L0 tables into GPTBR */
698 	write_gptbr_el3(((gpt_config.plat_gpt_l0_base >> GPTBR_BADDR_VAL_SHIFT)
699 			>> GPTBR_BADDR_SHIFT) & GPTBR_BADDR_MASK);
700 
701 	/* GPCCR_EL3.PPS */
702 	gpccr_el3 = SET_GPCCR_PPS(gpt_config.pps);
703 
704 	/* GPCCR_EL3.PGS */
705 	gpccr_el3 |= SET_GPCCR_PGS(gpt_config.pgs);
706 
707 	/*
708 	 * Since EL3 maps the L1 region as Inner shareable, use the same
709 	 * shareability attribute for GPC as well so that
710 	 * GPC fetches are visible to PEs
711 	 */
712 	gpccr_el3 |= SET_GPCCR_SH(GPCCR_SH_IS);
713 
714 	/* Outer and Inner cacheability set to Normal memory, WB, RA, WA. */
715 	gpccr_el3 |= SET_GPCCR_ORGN(GPCCR_ORGN_WB_RA_WA);
716 	gpccr_el3 |= SET_GPCCR_IRGN(GPCCR_IRGN_WB_RA_WA);
717 
718 	/* Prepopulate GPCCR_EL3 but don't enable GPC yet */
719 	write_gpccr_el3(gpccr_el3);
720 	isb();
721 
722 	/* Invalidate any stale TLB entries and any cached register fields */
723 	tlbipaallos();
724 	dsb();
725 	isb();
726 
727 	/* Enable GPT */
728 	gpccr_el3 |= GPCCR_GPC_BIT;
729 
730 	/* TODO: Configure GPCCR_EL3_GPCP for Fault control. */
731 	write_gpccr_el3(gpccr_el3);
732 	isb();
733 	tlbipaallos();
734 	dsb();
735 	isb();
736 
737 	return 0;
738 }
739 
740 /*
741  * Public API to disable granule protection checks.
742  */
743 void gpt_disable(void)
744 {
745 	u_register_t gpccr_el3 = read_gpccr_el3();
746 
747 	write_gpccr_el3(gpccr_el3 & ~GPCCR_GPC_BIT);
748 	dsbsy();
749 	isb();
750 }
751 
752 /*
753  * Public API that initializes the entire protected space to GPT_GPI_ANY using
754  * the L0 tables (block descriptors). Ideally, this function is invoked prior
755  * to DDR discovery and initialization. The MMU must be initialized before
756  * calling this function.
757  *
758  * Parameters
759  *   pps		PPS value to use for table generation
760  *   l0_mem_base	Base address of L0 tables in memory.
761  *   l0_mem_size	Total size of memory available for L0 tables.
762  *
763  * Return
764  *   Negative Linux error code in the event of a failure, 0 for success.
765  */
766 int gpt_init_l0_tables(gpccr_pps_e pps, uintptr_t l0_mem_base,
767 		       size_t l0_mem_size)
768 {
769 	int ret;
770 	uint64_t gpt_desc;
771 
772 	/* Ensure that MMU and Data caches are enabled. */
773 	assert((read_sctlr_el3() & SCTLR_C_BIT) != 0U);
774 
775 	/* Validate other parameters. */
776 	ret = gpt_validate_l0_params(pps, l0_mem_base, l0_mem_size);
777 	if (ret != 0) {
778 		return ret;
779 	}
780 
781 	/* Create the descriptor to initialize L0 entries with. */
782 	gpt_desc = GPT_L0_BLK_DESC(GPT_GPI_ANY);
783 
784 	/* Iterate through all L0 entries */
785 	for (unsigned int i = 0U; i < GPT_L0_REGION_COUNT(gpt_config.t); i++) {
786 		((uint64_t *)l0_mem_base)[i] = gpt_desc;
787 	}
788 
789 	/* Flush updated L0 tables to memory. */
790 	flush_dcache_range((uintptr_t)l0_mem_base,
791 			   (size_t)GPT_L0_TABLE_SIZE(gpt_config.t));
792 
793 	/* Stash the L0 base address once initial setup is complete. */
794 	gpt_config.plat_gpt_l0_base = l0_mem_base;
795 
796 	return 0;
797 }
798 
799 /*
800  * Public API that carves out PAS regions from the L0 tables and builds any L1
801  * tables that are needed. This function ideally is run after DDR discovery and
802  * initialization. The L0 tables must have already been initialized to GPI_ANY
803  * when this function is called.
804  *
805  * This function can be called multiple times with different L1 memory ranges
806  * and PAS regions if it is desirable to place L1 tables in different locations
807  * in memory. (ex: you have multiple DDR banks and want to place the L1 tables
808  * in the DDR bank that they control)
809  *
810  * Parameters
811  *   pgs		PGS value to use for table generation.
812  *   l1_mem_base	Base address of memory used for L1 tables.
813  *   l1_mem_size	Total size of memory available for L1 tables.
814  *   *pas_regions	Pointer to PAS regions structure array.
815  *   pas_count		Total number of PAS regions.
816  *
817  * Return
818  *   Negative Linux error code in the event of a failure, 0 for success.
819  */
820 int gpt_init_pas_l1_tables(gpccr_pgs_e pgs, uintptr_t l1_mem_base,
821 			   size_t l1_mem_size, pas_region_t *pas_regions,
822 			   unsigned int pas_count)
823 {
824 	int ret;
825 	int l1_gpt_cnt;
826 
827 	/* Ensure that MMU and Data caches are enabled. */
828 	assert((read_sctlr_el3() & SCTLR_C_BIT) != 0U);
829 
830 	/* PGS is needed for gpt_validate_pas_mappings so check it now. */
831 	if (pgs > GPT_PGS_MAX) {
832 		ERROR("[GPT] Invalid PGS: 0x%x\n", pgs);
833 		return -EINVAL;
834 	}
835 	gpt_config.pgs = pgs;
836 	gpt_config.p = gpt_p_lookup[pgs];
837 
838 	/* Make sure L0 tables have been initialized. */
839 	if (gpt_config.plat_gpt_l0_base == 0U) {
840 		ERROR("[GPT] L0 tables must be initialized first!\n");
841 		return -EPERM;
842 	}
843 
844 	/* Check if L1 GPTs are required and how many. */
845 	l1_gpt_cnt = gpt_validate_pas_mappings(pas_regions, pas_count);
846 	if (l1_gpt_cnt < 0) {
847 		return l1_gpt_cnt;
848 	}
849 
850 	VERBOSE("[GPT] %u L1 GPTs requested.\n", l1_gpt_cnt);
851 
852 	/* If L1 tables are needed then validate the L1 parameters. */
853 	if (l1_gpt_cnt > 0) {
854 		ret = gpt_validate_l1_params(l1_mem_base, l1_mem_size,
855 		      l1_gpt_cnt);
856 		if (ret != 0) {
857 			return ret;
858 		}
859 
860 		/* Set up parameters for L1 table generation. */
861 		gpt_l1_tbl = l1_mem_base;
862 		gpt_next_l1_tbl_idx = 0U;
863 	}
864 
865 	INFO("[GPT] Boot Configuration\n");
866 	INFO("  PPS/T:     0x%x/%u\n", gpt_config.pps, gpt_config.t);
867 	INFO("  PGS/P:     0x%x/%u\n", gpt_config.pgs, gpt_config.p);
868 	INFO("  L0GPTSZ/S: 0x%x/%u\n", GPT_L0GPTSZ, GPT_S_VAL);
869 	INFO("  PAS count: 0x%x\n", pas_count);
870 	INFO("  L0 base:   0x%lx\n", gpt_config.plat_gpt_l0_base);
871 
872 	/* Generate the tables in memory. */
873 	for (unsigned int idx = 0U; idx < pas_count; idx++) {
874 		INFO("[GPT] PAS[%u]: base 0x%lx, size 0x%lx, GPI 0x%x, type 0x%x\n",
875 		     idx, pas_regions[idx].base_pa, pas_regions[idx].size,
876 		     GPT_PAS_ATTR_GPI(pas_regions[idx].attrs),
877 		     GPT_PAS_ATTR_MAP_TYPE(pas_regions[idx].attrs));
878 
879 		/* Check if a block or table descriptor is required */
880 		if (GPT_PAS_ATTR_MAP_TYPE(pas_regions[idx].attrs) ==
881 		    GPT_PAS_ATTR_MAP_TYPE_BLOCK) {
882 			gpt_generate_l0_blk_desc(&pas_regions[idx]);
883 
884 		} else {
885 			gpt_generate_l0_tbl_desc(&pas_regions[idx]);
886 		}
887 	}
888 
889 	/* Flush modified L0 tables. */
890 	flush_l0_for_pas_array(pas_regions, pas_count);
891 
892 	/* Flush L1 tables if needed. */
893 	if (l1_gpt_cnt > 0) {
894 		flush_dcache_range(l1_mem_base,
895 				   GPT_L1_TABLE_SIZE(gpt_config.p) *
896 				   l1_gpt_cnt);
897 	}
898 
899 	/* Make sure that all the entries are written to the memory. */
900 	dsbishst();
901 	tlbipaallos();
902 	dsb();
903 	isb();
904 
905 	return 0;
906 }
907 
908 /*
909  * Public API to initialize the runtime gpt_config structure based on the values
910  * present in the GPTBR_EL3 and GPCCR_EL3 registers. GPT initialization
911  * typically happens in a bootloader stage prior to setting up the EL3 runtime
912  * environment for the granule transition service so this function detects the
913  * initialization from a previous stage. Granule protection checks must be
914  * enabled already or this function will return an error.
915  *
916  * Return
917  *   Negative Linux error code in the event of a failure, 0 for success.
918  */
919 int gpt_runtime_init(void)
920 {
921 	u_register_t reg;
922 
923 	/* Ensure that MMU and Data caches are enabled. */
924 	assert((read_sctlr_el3() & SCTLR_C_BIT) != 0U);
925 
926 	/* Ensure GPC are already enabled. */
927 	if ((read_gpccr_el3() & GPCCR_GPC_BIT) == 0U) {
928 		ERROR("[GPT] Granule protection checks are not enabled!\n");
929 		return -EPERM;
930 	}
931 
932 	/*
933 	 * Read the L0 table address from GPTBR, we don't need the L1 base
934 	 * address since those are included in the L0 tables as needed.
935 	 */
936 	reg = read_gptbr_el3();
937 	gpt_config.plat_gpt_l0_base = ((reg >> GPTBR_BADDR_SHIFT) &
938 				      GPTBR_BADDR_MASK) <<
939 				      GPTBR_BADDR_VAL_SHIFT;
940 
941 	/* Read GPCCR to get PGS and PPS values. */
942 	reg = read_gpccr_el3();
943 	gpt_config.pps = (reg >> GPCCR_PPS_SHIFT) & GPCCR_PPS_MASK;
944 	gpt_config.t = gpt_t_lookup[gpt_config.pps];
945 	gpt_config.pgs = (reg >> GPCCR_PGS_SHIFT) & GPCCR_PGS_MASK;
946 	gpt_config.p = gpt_p_lookup[gpt_config.pgs];
947 
948 	VERBOSE("[GPT] Runtime Configuration\n");
949 	VERBOSE("  PPS/T:     0x%x/%u\n", gpt_config.pps, gpt_config.t);
950 	VERBOSE("  PGS/P:     0x%x/%u\n", gpt_config.pgs, gpt_config.p);
951 	VERBOSE("  L0GPTSZ/S: 0x%x/%u\n", GPT_L0GPTSZ, GPT_S_VAL);
952 	VERBOSE("  L0 base:   0x%lx\n", gpt_config.plat_gpt_l0_base);
953 
954 	return 0;
955 }
956 
957 /*
958  * The L1 descriptors are protected by a spinlock to ensure that multiple
959  * CPUs do not attempt to change the descriptors at once. In the future it
960  * would be better to have separate spinlocks for each L1 descriptor.
961  */
962 static spinlock_t gpt_lock;
963 
964 /*
965  * A helper to write the value (target_pas << gpi_shift) to the index of
966  * the gpt_l1_addr
967  */
968 static inline void write_gpt(uint64_t *gpt_l1_desc, uint64_t *gpt_l1_addr,
969 			     unsigned int gpi_shift, unsigned int idx,
970 			     unsigned int target_pas)
971 {
972 	*gpt_l1_desc &= ~(GPT_L1_GRAN_DESC_GPI_MASK << gpi_shift);
973 	*gpt_l1_desc |= ((uint64_t)target_pas << gpi_shift);
974 	gpt_l1_addr[idx] = *gpt_l1_desc;
975 }
976 
977 /*
978  * Helper to retrieve the gpt_l1_* information from the base address
979  * returned in gpi_info
980  */
981 static int get_gpi_params(uint64_t base, gpi_info_t *gpi_info)
982 {
983 	uint64_t gpt_l0_desc, *gpt_l0_base;
984 
985 	gpt_l0_base = (uint64_t *)gpt_config.plat_gpt_l0_base;
986 	gpt_l0_desc = gpt_l0_base[GPT_L0_IDX(base)];
987 	if (GPT_L0_TYPE(gpt_l0_desc) != GPT_L0_TYPE_TBL_DESC) {
988 		VERBOSE("[GPT] Granule is not covered by a table descriptor!\n");
989 		VERBOSE("      Base=0x%" PRIx64 "\n", base);
990 		return -EINVAL;
991 	}
992 
993 	/* Get the table index and GPI shift from PA. */
994 	gpi_info->gpt_l1_addr = GPT_L0_TBLD_ADDR(gpt_l0_desc);
995 	gpi_info->idx = GPT_L1_IDX(gpt_config.p, base);
996 	gpi_info->gpi_shift = GPT_L1_GPI_IDX(gpt_config.p, base) << 2;
997 
998 	gpi_info->gpt_l1_desc = (gpi_info->gpt_l1_addr)[gpi_info->idx];
999 	gpi_info->gpi = (gpi_info->gpt_l1_desc >> gpi_info->gpi_shift) &
1000 		GPT_L1_GRAN_DESC_GPI_MASK;
1001 	return 0;
1002 }
1003 
1004 /*
1005  * This function is the granule transition delegate service. When a granule
1006  * transition request occurs it is routed to this function to have the request,
1007  * if valid, fulfilled following A1.1.1 Delegate of RME supplement
1008  *
1009  * TODO: implement support for transitioning multiple granules at once.
1010  *
1011  * Parameters
1012  *   base		Base address of the region to transition, must be
1013  *			aligned to granule size.
1014  *   size		Size of region to transition, must be aligned to granule
1015  *			size.
1016  *   src_sec_state	Security state of the caller.
1017  *
1018  * Return
1019  *   Negative Linux error code in the event of a failure, 0 for success.
1020  */
1021 int gpt_delegate_pas(uint64_t base, size_t size, unsigned int src_sec_state)
1022 {
1023 	gpi_info_t gpi_info;
1024 	uint64_t nse;
1025 	int res;
1026 	unsigned int target_pas;
1027 
1028 	/* Ensure that the tables have been set up before taking requests. */
1029 	assert(gpt_config.plat_gpt_l0_base != 0UL);
1030 
1031 	/* Ensure that caches are enabled. */
1032 	assert((read_sctlr_el3() & SCTLR_C_BIT) != 0UL);
1033 
1034 	/* Delegate request can only come from REALM or SECURE */
1035 	assert(src_sec_state == SMC_FROM_REALM ||
1036 	       src_sec_state == SMC_FROM_SECURE);
1037 
1038 	/* See if this is a single or a range of granule transition. */
1039 	if (size != GPT_PGS_ACTUAL_SIZE(gpt_config.p)) {
1040 		return -EINVAL;
1041 	}
1042 
1043 	/* Check that base and size are valid */
1044 	if ((ULONG_MAX - base) < size) {
1045 		VERBOSE("[GPT] Transition request address overflow!\n");
1046 		VERBOSE("      Base=0x%" PRIx64 "\n", base);
1047 		VERBOSE("      Size=0x%lx\n", size);
1048 		return -EINVAL;
1049 	}
1050 
1051 	/* Make sure base and size are valid. */
1052 	if (((base & (GPT_PGS_ACTUAL_SIZE(gpt_config.p) - 1)) != 0UL) ||
1053 	    ((size & (GPT_PGS_ACTUAL_SIZE(gpt_config.p) - 1)) != 0UL) ||
1054 	    (size == 0UL) ||
1055 	    ((base + size) >= GPT_PPS_ACTUAL_SIZE(gpt_config.t))) {
1056 		VERBOSE("[GPT] Invalid granule transition address range!\n");
1057 		VERBOSE("      Base=0x%" PRIx64 "\n", base);
1058 		VERBOSE("      Size=0x%lx\n", size);
1059 		return -EINVAL;
1060 	}
1061 
1062 	target_pas = GPT_GPI_REALM;
1063 	if (src_sec_state == SMC_FROM_SECURE) {
1064 		target_pas = GPT_GPI_SECURE;
1065 	}
1066 
1067 	/*
1068 	 * Access to L1 tables is controlled by a global lock to ensure
1069 	 * that no more than one CPU is allowed to make changes at any
1070 	 * given time.
1071 	 */
1072 	spin_lock(&gpt_lock);
1073 	res = get_gpi_params(base, &gpi_info);
1074 	if (res != 0) {
1075 		spin_unlock(&gpt_lock);
1076 		return res;
1077 	}
1078 
1079 	/* Check that the current address is in NS state */
1080 	if (gpi_info.gpi != GPT_GPI_NS) {
1081 		VERBOSE("[GPT] Only Granule in NS state can be delegated.\n");
1082 		VERBOSE("      Caller: %u, Current GPI: %u\n", src_sec_state,
1083 			gpi_info.gpi);
1084 		spin_unlock(&gpt_lock);
1085 		return -EPERM;
1086 	}
1087 
1088 	if (src_sec_state == SMC_FROM_SECURE) {
1089 		nse = (uint64_t)GPT_NSE_SECURE << GPT_NSE_SHIFT;
1090 	} else {
1091 		nse = (uint64_t)GPT_NSE_REALM << GPT_NSE_SHIFT;
1092 	}
1093 
1094 	/*
1095 	 * In order to maintain mutual distrust between Realm and Secure
1096 	 * states, remove any data speculatively fetched into the target
1097 	 * physical address space. Issue DC CIPAPA over address range
1098 	 */
1099 	if (is_feat_mte2_supported()) {
1100 		flush_dcache_to_popa_range_mte2(nse | base,
1101 					GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1102 	} else {
1103 		flush_dcache_to_popa_range(nse | base,
1104 					   GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1105 	}
1106 
1107 	write_gpt(&gpi_info.gpt_l1_desc, gpi_info.gpt_l1_addr,
1108 		  gpi_info.gpi_shift, gpi_info.idx, target_pas);
1109 	dsboshst();
1110 
1111 	gpt_tlbi_by_pa_ll(base, GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1112 	dsbosh();
1113 
1114 	nse = (uint64_t)GPT_NSE_NS << GPT_NSE_SHIFT;
1115 
1116 	if (is_feat_mte2_supported()) {
1117 		flush_dcache_to_popa_range_mte2(nse | base,
1118 					   GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1119 	} else {
1120 		flush_dcache_to_popa_range(nse | base,
1121 					   GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1122 	}
1123 
1124 	/* Unlock access to the L1 tables. */
1125 	spin_unlock(&gpt_lock);
1126 
1127 	/*
1128 	 * The isb() will be done as part of context
1129 	 * synchronization when returning to lower EL
1130 	 */
1131 	VERBOSE("[GPT] Granule 0x%" PRIx64 ", GPI 0x%x->0x%x\n",
1132 		base, gpi_info.gpi, target_pas);
1133 
1134 	return 0;
1135 }
1136 
1137 /*
1138  * This function is the granule transition undelegate service. When a granule
1139  * transition request occurs it is routed to this function where the request is
1140  * validated then fulfilled if possible.
1141  *
1142  * TODO: implement support for transitioning multiple granules at once.
1143  *
1144  * Parameters
1145  *   base		Base address of the region to transition, must be
1146  *			aligned to granule size.
1147  *   size		Size of region to transition, must be aligned to granule
1148  *			size.
1149  *   src_sec_state	Security state of the caller.
1150  *
1151  * Return
1152  *    Negative Linux error code in the event of a failure, 0 for success.
1153  */
1154 int gpt_undelegate_pas(uint64_t base, size_t size, unsigned int src_sec_state)
1155 {
1156 	gpi_info_t gpi_info;
1157 	uint64_t nse;
1158 	int res;
1159 
1160 	/* Ensure that the tables have been set up before taking requests. */
1161 	assert(gpt_config.plat_gpt_l0_base != 0UL);
1162 
1163 	/* Ensure that MMU and caches are enabled. */
1164 	assert((read_sctlr_el3() & SCTLR_C_BIT) != 0UL);
1165 
1166 	/* Delegate request can only come from REALM or SECURE */
1167 	assert(src_sec_state == SMC_FROM_REALM ||
1168 	       src_sec_state == SMC_FROM_SECURE);
1169 
1170 	/* See if this is a single or a range of granule transition. */
1171 	if (size != GPT_PGS_ACTUAL_SIZE(gpt_config.p)) {
1172 		return -EINVAL;
1173 	}
1174 
1175 	/* Check that base and size are valid */
1176 	if ((ULONG_MAX - base) < size) {
1177 		VERBOSE("[GPT] Transition request address overflow!\n");
1178 		VERBOSE("      Base=0x%" PRIx64 "\n", base);
1179 		VERBOSE("      Size=0x%lx\n", size);
1180 		return -EINVAL;
1181 	}
1182 
1183 	/* Make sure base and size are valid. */
1184 	if (((base & (GPT_PGS_ACTUAL_SIZE(gpt_config.p) - 1)) != 0UL) ||
1185 	    ((size & (GPT_PGS_ACTUAL_SIZE(gpt_config.p) - 1)) != 0UL) ||
1186 	    (size == 0UL) ||
1187 	    ((base + size) >= GPT_PPS_ACTUAL_SIZE(gpt_config.t))) {
1188 		VERBOSE("[GPT] Invalid granule transition address range!\n");
1189 		VERBOSE("      Base=0x%" PRIx64 "\n", base);
1190 		VERBOSE("      Size=0x%lx\n", size);
1191 		return -EINVAL;
1192 	}
1193 
1194 	/*
1195 	 * Access to L1 tables is controlled by a global lock to ensure
1196 	 * that no more than one CPU is allowed to make changes at any
1197 	 * given time.
1198 	 */
1199 	spin_lock(&gpt_lock);
1200 
1201 	res = get_gpi_params(base, &gpi_info);
1202 	if (res != 0) {
1203 		spin_unlock(&gpt_lock);
1204 		return res;
1205 	}
1206 
1207 	/* Check that the current address is in the delegated state */
1208 	if ((src_sec_state == SMC_FROM_REALM  &&
1209 	     gpi_info.gpi != GPT_GPI_REALM) ||
1210 	    (src_sec_state == SMC_FROM_SECURE &&
1211 	     gpi_info.gpi != GPT_GPI_SECURE)) {
1212 		VERBOSE("[GPT] Only Granule in REALM or SECURE state can be undelegated.\n");
1213 		VERBOSE("      Caller: %u, Current GPI: %u\n", src_sec_state,
1214 			gpi_info.gpi);
1215 		spin_unlock(&gpt_lock);
1216 		return -EPERM;
1217 	}
1218 
1219 
1220 	/* In order to maintain mutual distrust between Realm and Secure
1221 	 * states, remove access now, in order to guarantee that writes
1222 	 * to the currently-accessible physical address space will not
1223 	 * later become observable.
1224 	 */
1225 	write_gpt(&gpi_info.gpt_l1_desc, gpi_info.gpt_l1_addr,
1226 		  gpi_info.gpi_shift, gpi_info.idx, GPT_GPI_NO_ACCESS);
1227 	dsboshst();
1228 
1229 	gpt_tlbi_by_pa_ll(base, GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1230 	dsbosh();
1231 
1232 	if (src_sec_state == SMC_FROM_SECURE) {
1233 		nse = (uint64_t)GPT_NSE_SECURE << GPT_NSE_SHIFT;
1234 	} else {
1235 		nse = (uint64_t)GPT_NSE_REALM << GPT_NSE_SHIFT;
1236 	}
1237 
1238 	/* Ensure that the scrubbed data has made it past the PoPA */
1239 	if (is_feat_mte2_supported()) {
1240 		flush_dcache_to_popa_range_mte2(nse | base,
1241 					   GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1242 	} else {
1243 		flush_dcache_to_popa_range(nse | base,
1244 					   GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1245 	}
1246 
1247 	/*
1248 	 * Remove any data loaded speculatively
1249 	 * in NS space from before the scrubbing
1250 	 */
1251 	nse = (uint64_t)GPT_NSE_NS << GPT_NSE_SHIFT;
1252 
1253 	if (is_feat_mte2_supported()) {
1254 		flush_dcache_to_popa_range_mte2(nse | base,
1255 					   GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1256 	} else {
1257 		flush_dcache_to_popa_range(nse | base,
1258 					   GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1259 	}
1260 
1261 	/* Clear existing GPI encoding and transition granule. */
1262 	write_gpt(&gpi_info.gpt_l1_desc, gpi_info.gpt_l1_addr,
1263 		  gpi_info.gpi_shift, gpi_info.idx, GPT_GPI_NS);
1264 	dsboshst();
1265 
1266 	/* Ensure that all agents observe the new NS configuration */
1267 	gpt_tlbi_by_pa_ll(base, GPT_PGS_ACTUAL_SIZE(gpt_config.p));
1268 	dsbosh();
1269 
1270 	/* Unlock access to the L1 tables. */
1271 	spin_unlock(&gpt_lock);
1272 
1273 	/*
1274 	 * The isb() will be done as part of context
1275 	 * synchronization when returning to lower EL
1276 	 */
1277 	VERBOSE("[GPT] Granule 0x%" PRIx64 ", GPI 0x%x->0x%x\n",
1278 		base, gpi_info.gpi, GPT_GPI_NS);
1279 
1280 	return 0;
1281 }
1282