45  * - Each MPU region is described by TWO entries:
49  *   We might run out of available entries in the MPU map because of
57  *   - All enabled entries are grouped towards the end of the map.
62  *   - No disabled MPU entries allowed in between.
65  * For foreground map to be valid, its entries must follow these rules:
139  * Return the pointer to the entry encompassing @a addr out of an array of MPU entries.
144  * @param[in]  entries Array of MPU entries.
156 struct xtensa_mpu_entry *check_addr_in_mpu_entries(const struct xtensa_mpu_entry *entries,  in check_addr_in_mpu_entries()  argument
168 	if (addr < xtensa_mpu_entry_start_address_get(&entries[first_enabled_idx])) {  in check_addr_in_mpu_entries()
175 		s_addr = xtensa_mpu_entry_start_address_get(&entries[idx]);  in check_addr_in_mpu_entries()
176 		e_addr = xtensa_mpu_entry_start_address_get(&entries[idx + 1]);  in check_addr_in_mpu_entries()
179 			ret = &entries[idx];  in check_addr_in_mpu_entries()
185 	s_addr = xtensa_mpu_entry_start_address_get(&entries[idx]);  in check_addr_in_mpu_entries()
188 		ret = &entries[idx];  in check_addr_in_mpu_entries()
213  * @param entries Array of MPU entries with XTENSA_MPU_NUM_ENTRIES elements.
218 static inline uint8_t find_first_enabled_entry(const struct xtensa_mpu_entry *entries)  in find_first_enabled_entry()  argument
224 		if (entries[first_enabled_idx].as.p.enable) {  in find_first_enabled_entry()
233  * Compare two MPU entries.
235  * This is used by qsort to compare two MPU entries on their ordering
263  * Sort the MPU entries base on starting address.
265  * This sorts the MPU entries in ascending order of starting address.
266  * After sorting, it rewrites the segment numbers of all entries.
268 static void sort_entries(struct xtensa_mpu_entry *entries)  in sort_entries()  argument
270 	qsort(entries, XTENSA_MPU_NUM_ENTRIES, sizeof(entries[0]), compare_entries);  in sort_entries()
274 		entries[idx].at.p.segment = idx;  in sort_entries()
279  * Consolidate the MPU entries.
281  * This removes consecutive entries where the attributes are the same.
283  * @param entries Array of MPU entries with XTENSA_MPU_NUM_ENTRIES elements.
288 static uint8_t consolidate_entries(struct xtensa_mpu_entry *entries,  in consolidate_entries()  argument
296 	/* For each a pair of entries... */  in consolidate_entries()
298 		struct xtensa_mpu_entry *entry_0 = &entries[idx_0];  in consolidate_entries()
299 		struct xtensa_mpu_entry *entry_1 = &entries[idx_1];  in consolidate_entries()
312 			 * If both entries have the same address, the higher index  in consolidate_entries()
349 		/* Go through the map from the end and copy enabled entries in place. */  in consolidate_entries()
351 			struct xtensa_mpu_entry *entry_rd = &entries[read_idx];  in consolidate_entries()
357 				entry_wr = &entries[write_idx];  in consolidate_entries()
370 			struct xtensa_mpu_entry *e = &entries[idx_0];  in consolidate_entries()
381 			/* Use default memory type for disabled entries. */  in consolidate_entries()
385 		/* No need to conlidate entries. Map is same as before. */  in consolidate_entries()
396  * start and end entries. This may re-use existing entries or add new
397  * entries to the map.
419 	struct xtensa_mpu_entry *entries = map->entries;  in mpu_map_region_add()  local
426 	first_enabled_idx = find_first_enabled_entry(entries);  in mpu_map_region_add()
432 		 * at all. This is because we group all enabled entries at  in mpu_map_region_add()
435 		struct xtensa_mpu_entry *last_entry = &entries[XTENSA_MPU_NUM_ENTRIES - 1];  in mpu_map_region_add()
439 			/* Empty table, so populate the entries as-is. */  in mpu_map_region_add()
445 				entry_slot_s = &entries[XTENSA_MPU_NUM_ENTRIES - 1];  in mpu_map_region_add()
453 				 * Populate the last two entries to indicate  in mpu_map_region_add()
459 				entry_slot_s = &entries[XTENSA_MPU_NUM_ENTRIES - 2];  in mpu_map_region_add()
460 				entry_slot_e = &entries[XTENSA_MPU_NUM_ENTRIES - 1];  in mpu_map_region_add()
475 		first_enabled_idx = consolidate_entries(entries, first_enabled_idx);  in mpu_map_region_add()
484 		       check_addr_in_mpu_entries(entries, start_addr, first_enabled_idx,  in mpu_map_region_add()
487 		       check_addr_in_mpu_entries(entries, end_addr, first_enabled_idx,  in mpu_map_region_add()
502 	 * we can reuse those entries without adding new one.  in mpu_map_region_add()
516 	 * we start adding entries, as we will need to apply the same  in mpu_map_region_add()
532 		 * We will sort the entries later.  in mpu_map_region_add()
536 		entry_slot_s = &entries[first_enabled_idx];  in mpu_map_region_add()
551 		 * We will sort the entries later.  in mpu_map_region_add()
555 		entry_slot_e = &entries[first_enabled_idx];  in mpu_map_region_add()
566 	/* Sort the entries in ascending order of starting address */  in mpu_map_region_add()
567 	sort_entries(entries);  in mpu_map_region_add()
570 	 * Need to figure out where the start and end entries are as sorting  in mpu_map_region_add()
574 		       check_addr_in_mpu_entries(entries, start_addr, first_enabled_idx,  in mpu_map_region_add()
577 		       check_addr_in_mpu_entries(entries, end_addr, first_enabled_idx,  in mpu_map_region_add()
590 		 * update entries will change the attribute of last entry  in mpu_map_region_add()
597 	 * Any existing entries between the "newly" popluated start and  in mpu_map_region_add()
598 	 * end entries must bear the same attributes. So modify them  in mpu_map_region_add()
602 		xtensa_mpu_entry_attributes_set(&entries[idx], access_rights, memory_type);  in mpu_map_region_add()
644 	 * Clear MPU entries first, then write MPU entries in reverse order.  in xtensa_mpu_map_write()
647 	 * two consecutive entries, and that the addresses of all entries  in xtensa_mpu_map_write()
649 	 * To ensure this, we clear out the entries first then write them  in xtensa_mpu_map_write()
659 				 : : "a"(map->entries[entry].at), "a"(map->entries[entry].as));  in xtensa_mpu_map_write()
677 	 * Clear the foreground MPU map so we can populate it later with valid entries.  in xtensa_mpu_init()
691 		/* Use default memory type for disabled entries. */  in xtensa_mpu_init()
694 		xtensa_mpu_map_fg_kernel.entries[entry] = ent;  in xtensa_mpu_init()
699 	 * Add necessary MPU entries for the memory regions of base Zephyr image.  in xtensa_mpu_init()
718 	 * Now for the entries for memory regions needed by SoC.  in xtensa_mpu_init()
735 	/* Consolidate entries so we have a compact map at boot. */  in xtensa_mpu_init()
736 	consolidate_entries(xtensa_mpu_map_fg_kernel.entries, first_enabled_idx);  in xtensa_mpu_init()
760 	 * Due to each memory region requiring 2 MPU entries to describe,  in arch_mem_domain_max_partitions_get()
763 	 * needs 2 entries (1 if the end of region already has an entry).  in arch_mem_domain_max_partitions_get()
764 	 * If they are all disjoint, it will need (2 * n) entries to  in arch_mem_domain_max_partitions_get()
835 	 * a region with default attributes. If entries already  in arch_mem_domain_partition_remove()
836 	 * exist for the region, the corresponding entries will  in arch_mem_domain_partition_remove()
837 	 * be updated with the default attributes. Or new entries  in arch_mem_domain_partition_remove()