| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright (C) 2013 Google, Inc. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; version 2 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| #include <stdlib.h> |
| #include <console/console.h> |
| #include <memrange.h> |
| |
| /* Coreboot doesn't have a free() function. Therefore, keep a cache of |
| * free'd entries. */ |
| static struct range_entry *free_list; |
| |
| static inline void range_entry_link(struct range_entry **prev_ptr, |
| struct range_entry *r) |
| { |
| r->next = *prev_ptr; |
| *prev_ptr = r; |
| } |
| |
| static inline void range_entry_unlink(struct range_entry **prev_ptr, |
| struct range_entry *r) |
| { |
| *prev_ptr = r->next; |
| r->next = NULL; |
| } |
| |
| static inline void range_entry_unlink_and_free(struct range_entry **prev_ptr, |
| struct range_entry *r) |
| { |
| range_entry_unlink(prev_ptr, r); |
| range_entry_link(&free_list, r); |
| } |
| |
| static struct range_entry *alloc_range(void) |
| { |
| if (free_list != NULL) { |
| struct range_entry *r; |
| |
| r = free_list; |
| range_entry_unlink(&free_list, r); |
| return r; |
| } |
| return malloc(sizeof(struct range_entry)); |
| } |
| |
| static inline struct range_entry * |
| range_list_add(struct range_entry **prev_ptr, resource_t begin, resource_t end, |
| unsigned long tag) |
| { |
| struct range_entry *new_entry; |
| |
| new_entry = alloc_range(); |
| if (new_entry == NULL) { |
| printk(BIOS_ERR, "Could not allocate range_entry!\n"); |
| return NULL; |
| } |
| new_entry->begin = begin; |
| new_entry->end = end; |
| new_entry->tag = tag; |
| range_entry_link(prev_ptr, new_entry); |
| |
| return new_entry; |
| } |
| |
| static void merge_neighbor_entries(struct memranges *ranges) |
| { |
| struct range_entry *cur; |
| struct range_entry *prev; |
| |
| prev = NULL; |
| /* Merge all neighbors and delete/free the leftover entry. */ |
| for (cur = ranges->entries; cur != NULL; cur = cur->next) { |
| /* First entry. Just set prev. */ |
| if (prev == NULL) { |
| prev = cur; |
| continue; |
| } |
| |
| /* If the previous entry merges with the current update the |
| * previous entry to cover full range and delete current from |
| * the list. */ |
| if (prev->end + 1 >= cur->begin && prev->tag == cur->tag) { |
| prev->end = cur->end; |
| range_entry_unlink_and_free(&prev->next, cur); |
| /* Set cur to prev so cur->next is valid since cur |
| * was just unlinked and free. */ |
| cur = prev; |
| continue; |
| } |
| |
| prev = cur; |
| } |
| } |
| |
| static void remove_memranges(struct memranges *ranges, |
| resource_t begin, resource_t end, |
| unsigned long unused) |
| { |
| struct range_entry *cur; |
| struct range_entry *next; |
| struct range_entry **prev_ptr; |
| |
| prev_ptr = &ranges->entries; |
| for (cur = ranges->entries; cur != NULL; cur = next) { |
| resource_t tmp_end; |
| |
| /* Cache the next value to handle unlinks. */ |
| next = cur->next; |
| |
| /* No other ranges are affected. */ |
| if (end < cur->begin) |
| break; |
| |
| /* The removal range starts after this one. */ |
| if (begin > cur->end) { |
| prev_ptr = &cur->next; |
| continue; |
| } |
| |
| /* The removal range overlaps with the current entry either |
| * partially or fully. However, we need to adjust the removal |
| * range for any holes. */ |
| if (begin <= cur->begin) { |
| begin = cur->begin; |
| |
| /* Full removal. */ |
| if (end >= cur->end) { |
| begin = cur->end + 1; |
| range_entry_unlink_and_free(prev_ptr, cur); |
| continue; |
| } |
| } |
| |
| /* prev_ptr can be set now that the unlink path wasn't taken. */ |
| prev_ptr = &cur->next; |
| |
| /* Clip the end fragment to do proper splitting. */ |
| tmp_end = end; |
| if (end > cur->end) |
| tmp_end = cur->end; |
| |
| /* Hole punched in middle of entry. */ |
| if (begin > cur->begin && tmp_end < cur->end) { |
| range_list_add(&cur->next, end + 1, cur->end, cur->tag); |
| cur->end = begin - 1; |
| break; |
| } |
| |
| /* Removal at beginning. */ |
| if (begin == cur->begin) |
| cur->begin = tmp_end + 1; |
| |
| /* Removal at end. */ |
| if (tmp_end == cur->end) |
| cur->end = begin - 1; |
| } |
| } |
| |
| static void merge_add_memranges(struct memranges *ranges, |
| resource_t begin, resource_t end, |
| unsigned long tag) |
| { |
| struct range_entry *cur; |
| struct range_entry **prev_ptr; |
| |
| prev_ptr = &ranges->entries; |
| |
| /* Remove all existing entries covered by the range. */ |
| remove_memranges(ranges, begin, end, -1); |
| |
| /* Find the entry to place the new entry after. Since |
| * remove_memranges() was called above there is a guranteed |
| * spot for this new entry. */ |
| for (cur = ranges->entries; cur != NULL; cur = cur->next) { |
| /* Found insertion spot before current entry. */ |
| if (end < cur->begin) |
| break; |
| |
| /* Keep track of previous entry to insert new entry after it. */ |
| prev_ptr = &cur->next; |
| |
| /* The new entry starts after this one. */ |
| if (begin > cur->end) |
| continue; |
| |
| } |
| |
| /* Add new entry and merge with neighbors. */ |
| range_list_add(prev_ptr, begin, end, tag); |
| merge_neighbor_entries(ranges); |
| } |
| |
| typedef void (*range_action_t)(struct memranges *ranges, |
| resource_t begin, resource_t end, |
| unsigned long tag); |
| |
| static void do_action(struct memranges *ranges, |
| resource_t base, resource_t size, unsigned long tag, |
| range_action_t action) |
| { |
| resource_t end; |
| resource_t begin; |
| |
| /* The addresses are aligned to 4096 bytes: the begin address is |
| * aligned down while the end address is aligned up to be conservative |
| * about the full range covered. */ |
| begin = ALIGN_DOWN(base, 4096); |
| end = begin + size + (base - begin); |
| end = ALIGN_UP(end, 4096) - 1; |
| action(ranges, begin, end, tag); |
| } |
| |
| void memranges_create_hole(struct memranges *ranges, |
| resource_t base, resource_t size) |
| { |
| do_action(ranges, base, size, -1, remove_memranges); |
| } |
| |
| void memranges_insert(struct memranges *ranges, |
| resource_t base, resource_t size, unsigned long tag) |
| { |
| do_action(ranges, base, size, tag, merge_add_memranges); |
| } |
| |
| struct collect_context { |
| struct memranges *ranges; |
| unsigned long tag; |
| }; |
| |
| static void collect_ranges(void *gp, struct device *dev, struct resource *res) |
| { |
| struct collect_context *ctx = gp; |
| |
| memranges_insert(ctx->ranges, res->base, res->size, ctx->tag); |
| } |
| |
| void memranges_add_resources(struct memranges *ranges, |
| unsigned long mask, unsigned long match, |
| unsigned long tag) |
| { |
| struct collect_context context; |
| |
| /* Only deal with MEM resources. */ |
| mask |= IORESOURCE_MEM; |
| match |= IORESOURCE_MEM; |
| |
| context.ranges = ranges; |
| context.tag = tag; |
| search_global_resources(mask, match, collect_ranges, &context); |
| } |
| |
| void memranges_init(struct memranges *ranges, |
| unsigned long mask, unsigned long match, |
| unsigned long tag) |
| { |
| ranges->entries = NULL; |
| memranges_add_resources(ranges, mask, match, tag); |
| } |
| |
| void memranges_teardown(struct memranges *ranges) |
| { |
| while (ranges->entries != NULL) { |
| range_entry_unlink_and_free(&ranges->entries, ranges->entries); |
| } |
| } |
| |
| void memranges_fill_holes_up_to(struct memranges *ranges, |
| resource_t limit, unsigned long tag) |
| { |
| struct range_entry *cur; |
| struct range_entry *prev; |
| |
| prev = NULL; |
| for (cur = ranges->entries; cur != NULL; cur = cur->next) { |
| /* First entry. Just set prev. */ |
| if (prev == NULL) { |
| prev = cur; |
| continue; |
| } |
| |
| /* If the previous entry does not directly preceed the current |
| * entry then add a new entry just after the previous one. */ |
| if (range_entry_end(prev) != cur->begin) { |
| resource_t end; |
| |
| end = cur->begin - 1; |
| if (end >= limit) |
| end = limit - 1; |
| range_list_add(&prev->next, range_entry_end(prev), |
| end, tag); |
| } |
| |
| prev = cur; |
| |
| /* Hit the requested range limit. No other entries after this |
| * are affected. */ |
| if (cur->begin >= limit) |
| break; |
| } |
| |
| /* Handle the case where the limit was never reached. A new entry needs |
| * to be added to cover the range up to the limit. */ |
| if (prev != NULL && range_entry_end(prev) < limit) |
| range_list_add(&prev->next, range_entry_end(prev), |
| limit - 1, tag); |
| |
| /* Merge all entries that were newly added. */ |
| merge_neighbor_entries(ranges); |
| } |