1 // SPDX-License-Identifier: GPL-2.0+
3 * EFI application memory management
5 * Copyright (c) 2016 Alexander Graf
9 #include <efi_loader.h>
13 #include <asm/global_data.h>
14 #include <linux/list_sort.h>
16 DECLARE_GLOBAL_DATA_PTR;
19 struct list_head link;
20 struct efi_mem_desc desc;
23 #define EFI_CARVE_NO_OVERLAP -1
24 #define EFI_CARVE_LOOP_AGAIN -2
25 #define EFI_CARVE_OVERLAPS_NONRAM -3
27 /* This list contains all memory map items */
30 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
31 void *efi_bounce_buffer;
35 * U-Boot services each EFI AllocatePool request as a separate
36 * (multiple) page allocation. We have to track the number of pages
37 * to be able to free the correct amount later.
38 * EFI requires 8 byte alignment for pool allocations, so we can
39 * prepend each allocation with an 64 bit header tracking the
40 * allocation size, and hand out the remainder to the caller.
42 struct efi_pool_allocation {
44 char data[] __aligned(ARCH_DMA_MINALIGN);
48 * Sorts the memory list from highest address to lowest address
50 * When allocating memory we should always start from the highest
51 * address chunk, so sort the memory list such that the first list
52 * iterator gets the highest address and goes lower from there.
54 static int efi_mem_cmp(void *priv, struct list_head *a, struct list_head *b)
56 struct efi_mem_list *mema = list_entry(a, struct efi_mem_list, link);
57 struct efi_mem_list *memb = list_entry(b, struct efi_mem_list, link);
59 if (mema->desc.physical_start == memb->desc.physical_start)
61 else if (mema->desc.physical_start < memb->desc.physical_start)
67 static void efi_mem_sort(void)
69 list_sort(NULL, &efi_mem, efi_mem_cmp);
73 * Unmaps all memory occupied by the carve_desc region from the
74 * list entry pointed to by map.
76 * Returns EFI_CARVE_NO_OVERLAP if the regions don't overlap.
77 * Returns EFI_CARVE_OVERLAPS_NONRAM if the carve and map overlap,
78 * and the map contains anything but free ram.
79 * (only when overlap_only_ram is true)
80 * Returns EFI_CARVE_LOOP_AGAIN if the mapping list should be traversed
81 * again, as it has been altered
82 * Returns the number of overlapping pages. The pages are removed from
85 * In case of EFI_CARVE_OVERLAPS_NONRAM it is the callers responsibility
86 * to readd the already carved out pages to the mapping.
88 static int efi_mem_carve_out(struct efi_mem_list *map,
89 struct efi_mem_desc *carve_desc,
90 bool overlap_only_ram)
92 struct efi_mem_list *newmap;
93 struct efi_mem_desc *map_desc = &map->desc;
94 uint64_t map_start = map_desc->physical_start;
95 uint64_t map_end = map_start + (map_desc->num_pages << EFI_PAGE_SHIFT);
96 uint64_t carve_start = carve_desc->physical_start;
97 uint64_t carve_end = carve_start +
98 (carve_desc->num_pages << EFI_PAGE_SHIFT);
100 /* check whether we're overlapping */
101 if ((carve_end <= map_start) || (carve_start >= map_end))
102 return EFI_CARVE_NO_OVERLAP;
104 /* We're overlapping with non-RAM, warn the caller if desired */
105 if (overlap_only_ram && (map_desc->type != EFI_CONVENTIONAL_MEMORY))
106 return EFI_CARVE_OVERLAPS_NONRAM;
108 /* Sanitize carve_start and carve_end to lie within our bounds */
109 carve_start = max(carve_start, map_start);
110 carve_end = min(carve_end, map_end);
112 /* Carving at the beginning of our map? Just move it! */
113 if (carve_start == map_start) {
114 if (map_end == carve_end) {
115 /* Full overlap, just remove map */
116 list_del(&map->link);
119 map->desc.physical_start = carve_end;
120 map->desc.num_pages = (map_end - carve_end)
124 return (carve_end - carve_start) >> EFI_PAGE_SHIFT;
128 * Overlapping maps, just split the list map at carve_start,
129 * it will get moved or removed in the next iteration.
131 * [ map_desc |__carve_start__| newmap ]
134 /* Create a new map from [ carve_start ... map_end ] */
135 newmap = calloc(1, sizeof(*newmap));
136 newmap->desc = map->desc;
137 newmap->desc.physical_start = carve_start;
138 newmap->desc.num_pages = (map_end - carve_start) >> EFI_PAGE_SHIFT;
139 /* Insert before current entry (descending address order) */
140 list_add_tail(&newmap->link, &map->link);
142 /* Shrink the map to [ map_start ... carve_start ] */
143 map_desc->num_pages = (carve_start - map_start) >> EFI_PAGE_SHIFT;
145 return EFI_CARVE_LOOP_AGAIN;
148 uint64_t efi_add_memory_map(uint64_t start, uint64_t pages, int memory_type,
149 bool overlap_only_ram)
151 struct list_head *lhandle;
152 struct efi_mem_list *newlist;
154 uint64_t carved_pages = 0;
156 debug("%s: 0x%" PRIx64 " 0x%" PRIx64 " %d %s\n", __func__,
157 start, pages, memory_type, overlap_only_ram ? "yes" : "no");
162 newlist = calloc(1, sizeof(*newlist));
163 newlist->desc.type = memory_type;
164 newlist->desc.physical_start = start;
165 newlist->desc.virtual_start = start;
166 newlist->desc.num_pages = pages;
168 switch (memory_type) {
169 case EFI_RUNTIME_SERVICES_CODE:
170 case EFI_RUNTIME_SERVICES_DATA:
171 newlist->desc.attribute = (1 << EFI_MEMORY_WB_SHIFT) |
172 (1ULL << EFI_MEMORY_RUNTIME_SHIFT);
175 newlist->desc.attribute = 1ULL << EFI_MEMORY_RUNTIME_SHIFT;
178 newlist->desc.attribute = 1 << EFI_MEMORY_WB_SHIFT;
182 /* Add our new map */
185 list_for_each(lhandle, &efi_mem) {
186 struct efi_mem_list *lmem;
189 lmem = list_entry(lhandle, struct efi_mem_list, link);
190 r = efi_mem_carve_out(lmem, &newlist->desc,
193 case EFI_CARVE_OVERLAPS_NONRAM:
195 * The user requested to only have RAM overlaps,
196 * but we hit a non-RAM region. Error out.
199 case EFI_CARVE_NO_OVERLAP:
200 /* Just ignore this list entry */
202 case EFI_CARVE_LOOP_AGAIN:
204 * We split an entry, but need to loop through
205 * the list again to actually carve it.
210 /* We carved a number of pages */
217 /* The list changed, we need to start over */
221 } while (carve_again);
223 if (overlap_only_ram && (carved_pages != pages)) {
225 * The payload wanted to have RAM overlaps, but we overlapped
226 * with an unallocated region. Error out.
231 /* Add our new map */
232 list_add_tail(&newlist->link, &efi_mem);
234 /* And make sure memory is listed in descending order */
240 static uint64_t efi_find_free_memory(uint64_t len, uint64_t max_addr)
242 struct list_head *lhandle;
244 list_for_each(lhandle, &efi_mem) {
245 struct efi_mem_list *lmem = list_entry(lhandle,
246 struct efi_mem_list, link);
247 struct efi_mem_desc *desc = &lmem->desc;
248 uint64_t desc_len = desc->num_pages << EFI_PAGE_SHIFT;
249 uint64_t desc_end = desc->physical_start + desc_len;
250 uint64_t curmax = min(max_addr, desc_end);
251 uint64_t ret = curmax - len;
253 /* We only take memory from free RAM */
254 if (desc->type != EFI_CONVENTIONAL_MEMORY)
257 /* Out of bounds for max_addr */
258 if ((ret + len) > max_addr)
261 /* Out of bounds for upper map limit */
262 if ((ret + len) > desc_end)
265 /* Out of bounds for lower map limit */
266 if (ret < desc->physical_start)
269 /* Return the highest address in this map within bounds */
277 * Allocate memory pages.
279 * @type type of allocation to be performed
280 * @memory_type usage type of the allocated memory
281 * @pages number of pages to be allocated
282 * @memory allocated memory
283 * @return status code
285 efi_status_t efi_allocate_pages(int type, int memory_type,
286 efi_uintn_t pages, uint64_t *memory)
288 u64 len = pages << EFI_PAGE_SHIFT;
289 efi_status_t r = EFI_SUCCESS;
293 case EFI_ALLOCATE_ANY_PAGES:
295 addr = efi_find_free_memory(len, gd->start_addr_sp);
301 case EFI_ALLOCATE_MAX_ADDRESS:
303 addr = efi_find_free_memory(len, *memory);
309 case EFI_ALLOCATE_ADDRESS:
310 /* Exact address, reserve it. The addr is already in *memory. */
314 /* UEFI doesn't specify other allocation types */
315 r = EFI_INVALID_PARAMETER;
319 if (r == EFI_SUCCESS) {
322 /* Reserve that map in our memory maps */
323 ret = efi_add_memory_map(addr, pages, memory_type, true);
327 /* Map would overlap, bail out */
328 r = EFI_OUT_OF_RESOURCES;
335 void *efi_alloc(uint64_t len, int memory_type)
338 uint64_t pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
341 r = efi_allocate_pages(0, memory_type, pages, &ret);
342 if (r == EFI_SUCCESS)
343 return (void*)(uintptr_t)ret;
351 * @memory start of the memory area to be freed
352 * @pages number of pages to be freed
353 * @return status code
355 efi_status_t efi_free_pages(uint64_t memory, efi_uintn_t pages)
359 r = efi_add_memory_map(memory, pages, EFI_CONVENTIONAL_MEMORY, false);
360 /* Merging of adjacent free regions is missing */
365 return EFI_NOT_FOUND;
369 * Allocate memory from pool.
371 * @pool_type type of the pool from which memory is to be allocated
372 * @size number of bytes to be allocated
373 * @buffer allocated memory
374 * @return status code
376 efi_status_t efi_allocate_pool(int pool_type, efi_uintn_t size, void **buffer)
379 efi_physical_addr_t t;
380 u64 num_pages = (size + sizeof(struct efi_pool_allocation) +
381 EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
388 r = efi_allocate_pages(0, pool_type, num_pages, &t);
390 if (r == EFI_SUCCESS) {
391 struct efi_pool_allocation *alloc = (void *)(uintptr_t)t;
392 alloc->num_pages = num_pages;
393 *buffer = alloc->data;
400 * Free memory from pool.
402 * @buffer start of memory to be freed
403 * @return status code
405 efi_status_t efi_free_pool(void *buffer)
408 struct efi_pool_allocation *alloc;
411 return EFI_INVALID_PARAMETER;
413 alloc = container_of(buffer, struct efi_pool_allocation, data);
414 /* Sanity check, was the supplied address returned by allocate_pool */
415 assert(((uintptr_t)alloc & EFI_PAGE_MASK) == 0);
417 r = efi_free_pages((uintptr_t)alloc, alloc->num_pages);
423 * Get map describing memory usage.
425 * @memory_map_size on entry the size, in bytes, of the memory map buffer,
426 * on exit the size of the copied memory map
427 * @memory_map buffer to which the memory map is written
428 * @map_key key for the memory map
429 * @descriptor_size size of an individual memory descriptor
430 * @descriptor_version version number of the memory descriptor structure
431 * @return status code
433 efi_status_t efi_get_memory_map(efi_uintn_t *memory_map_size,
434 struct efi_mem_desc *memory_map,
435 efi_uintn_t *map_key,
436 efi_uintn_t *descriptor_size,
437 uint32_t *descriptor_version)
439 efi_uintn_t map_size = 0;
441 struct list_head *lhandle;
442 efi_uintn_t provided_map_size = *memory_map_size;
444 list_for_each(lhandle, &efi_mem)
447 map_size = map_entries * sizeof(struct efi_mem_desc);
449 *memory_map_size = map_size;
451 if (provided_map_size < map_size)
452 return EFI_BUFFER_TOO_SMALL;
455 *descriptor_size = sizeof(struct efi_mem_desc);
457 if (descriptor_version)
458 *descriptor_version = EFI_MEMORY_DESCRIPTOR_VERSION;
460 /* Copy list into array */
462 /* Return the list in ascending order */
463 memory_map = &memory_map[map_entries - 1];
464 list_for_each(lhandle, &efi_mem) {
465 struct efi_mem_list *lmem;
467 lmem = list_entry(lhandle, struct efi_mem_list, link);
468 *memory_map = lmem->desc;
478 __weak void efi_add_known_memory(void)
483 for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
484 u64 ram_start = gd->bd->bi_dram[i].start;
485 u64 ram_size = gd->bd->bi_dram[i].size;
486 u64 start = (ram_start + EFI_PAGE_MASK) & ~EFI_PAGE_MASK;
487 u64 pages = (ram_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
489 efi_add_memory_map(start, pages, EFI_CONVENTIONAL_MEMORY,
494 int efi_memory_init(void)
496 unsigned long runtime_start, runtime_end, runtime_pages;
497 unsigned long uboot_start, uboot_pages;
498 unsigned long uboot_stack_size = 16 * 1024 * 1024;
500 efi_add_known_memory();
503 uboot_start = (gd->start_addr_sp - uboot_stack_size) & ~EFI_PAGE_MASK;
504 uboot_pages = (gd->ram_top - uboot_start) >> EFI_PAGE_SHIFT;
505 efi_add_memory_map(uboot_start, uboot_pages, EFI_LOADER_DATA, false);
507 /* Add Runtime Services */
508 runtime_start = (ulong)&__efi_runtime_start & ~EFI_PAGE_MASK;
509 runtime_end = (ulong)&__efi_runtime_stop;
510 runtime_end = (runtime_end + EFI_PAGE_MASK) & ~EFI_PAGE_MASK;
511 runtime_pages = (runtime_end - runtime_start) >> EFI_PAGE_SHIFT;
512 efi_add_memory_map(runtime_start, runtime_pages,
513 EFI_RUNTIME_SERVICES_CODE, false);
515 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
516 /* Request a 32bit 64MB bounce buffer region */
517 uint64_t efi_bounce_buffer_addr = 0xffffffff;
519 if (efi_allocate_pages(1, EFI_LOADER_DATA,
520 (64 * 1024 * 1024) >> EFI_PAGE_SHIFT,
521 &efi_bounce_buffer_addr) != EFI_SUCCESS)
524 efi_bounce_buffer = (void*)(uintptr_t)efi_bounce_buffer_addr;