mfd: Fix mismatch in twl4030 mutex lock-unlock
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / x86 / kernel / e820.c
blob3e2ef842531649de082d64298c6cb1044446c1bf
1 /*
2 * Handle the memory map.
3 * The functions here do the job until bootmem takes over.
5 * Getting sanitize_e820_map() in sync with i386 version by applying change:
6 * - Provisions for empty E820 memory regions (reported by certain BIOSes).
7 * Alex Achenbach <xela@slit.de>, December 2002.
8 * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/init.h>
14 #include <linux/crash_dump.h>
15 #include <linux/bootmem.h>
16 #include <linux/pfn.h>
17 #include <linux/suspend.h>
18 #include <linux/acpi.h>
19 #include <linux/firmware-map.h>
20 #include <linux/memblock.h>
22 #include <asm/e820.h>
23 #include <asm/proto.h>
24 #include <asm/setup.h>
27 * The e820 map is the map that gets modified e.g. with command line parameters
28 * and that is also registered with modifications in the kernel resource tree
29 * with the iomem_resource as parent.
31 * The e820_saved is directly saved after the BIOS-provided memory map is
32 * copied. It doesn't get modified afterwards. It's registered for the
33 * /sys/firmware/memmap interface.
35 * That memory map is not modified and is used as base for kexec. The kexec'd
36 * kernel should get the same memory map as the firmware provides. Then the
37 * user can e.g. boot the original kernel with mem=1G while still booting the
38 * next kernel with full memory.
40 struct e820map e820;
41 struct e820map e820_saved;
43 /* For PCI or other memory-mapped resources */
44 unsigned long pci_mem_start = 0xaeedbabe;
45 #ifdef CONFIG_PCI
46 EXPORT_SYMBOL(pci_mem_start);
47 #endif
50 * This function checks if any part of the range <start,end> is mapped
51 * with type.
53 int
54 e820_any_mapped(u64 start, u64 end, unsigned type)
56 int i;
58 for (i = 0; i < e820.nr_map; i++) {
59 struct e820entry *ei = &e820.map[i];
61 if (type && ei->type != type)
62 continue;
63 if (ei->addr >= end || ei->addr + ei->size <= start)
64 continue;
65 return 1;
67 return 0;
69 EXPORT_SYMBOL_GPL(e820_any_mapped);
72 * This function checks if the entire range <start,end> is mapped with type.
74 * Note: this function only works correct if the e820 table is sorted and
75 * not-overlapping, which is the case
77 int __init e820_all_mapped(u64 start, u64 end, unsigned type)
79 int i;
81 for (i = 0; i < e820.nr_map; i++) {
82 struct e820entry *ei = &e820.map[i];
84 if (type && ei->type != type)
85 continue;
86 /* is the region (part) in overlap with the current region ?*/
87 if (ei->addr >= end || ei->addr + ei->size <= start)
88 continue;
90 /* if the region is at the beginning of <start,end> we move
91 * start to the end of the region since it's ok until there
93 if (ei->addr <= start)
94 start = ei->addr + ei->size;
96 * if start is now at or beyond end, we're done, full
97 * coverage
99 if (start >= end)
100 return 1;
102 return 0;
106 * Add a memory region to the kernel e820 map.
108 static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
109 int type)
111 int x = e820x->nr_map;
113 if (x >= ARRAY_SIZE(e820x->map)) {
114 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
115 return;
118 e820x->map[x].addr = start;
119 e820x->map[x].size = size;
120 e820x->map[x].type = type;
121 e820x->nr_map++;
124 void __init e820_add_region(u64 start, u64 size, int type)
126 __e820_add_region(&e820, start, size, type);
129 static void __init e820_print_type(u32 type)
131 switch (type) {
132 case E820_RAM:
133 case E820_RESERVED_KERN:
134 printk(KERN_CONT "(usable)");
135 break;
136 case E820_RESERVED:
137 printk(KERN_CONT "(reserved)");
138 break;
139 case E820_ACPI:
140 printk(KERN_CONT "(ACPI data)");
141 break;
142 case E820_NVS:
143 printk(KERN_CONT "(ACPI NVS)");
144 break;
145 case E820_UNUSABLE:
146 printk(KERN_CONT "(unusable)");
147 break;
148 default:
149 printk(KERN_CONT "type %u", type);
150 break;
154 void __init e820_print_map(char *who)
156 int i;
158 for (i = 0; i < e820.nr_map; i++) {
159 printk(KERN_INFO " %s: %016Lx - %016Lx ", who,
160 (unsigned long long) e820.map[i].addr,
161 (unsigned long long)
162 (e820.map[i].addr + e820.map[i].size));
163 e820_print_type(e820.map[i].type);
164 printk(KERN_CONT "\n");
169 * Sanitize the BIOS e820 map.
171 * Some e820 responses include overlapping entries. The following
172 * replaces the original e820 map with a new one, removing overlaps,
173 * and resolving conflicting memory types in favor of highest
174 * numbered type.
176 * The input parameter biosmap points to an array of 'struct
177 * e820entry' which on entry has elements in the range [0, *pnr_map)
178 * valid, and which has space for up to max_nr_map entries.
179 * On return, the resulting sanitized e820 map entries will be in
180 * overwritten in the same location, starting at biosmap.
182 * The integer pointed to by pnr_map must be valid on entry (the
183 * current number of valid entries located at biosmap) and will
184 * be updated on return, with the new number of valid entries
185 * (something no more than max_nr_map.)
187 * The return value from sanitize_e820_map() is zero if it
188 * successfully 'sanitized' the map entries passed in, and is -1
189 * if it did nothing, which can happen if either of (1) it was
190 * only passed one map entry, or (2) any of the input map entries
191 * were invalid (start + size < start, meaning that the size was
192 * so big the described memory range wrapped around through zero.)
194 * Visually we're performing the following
195 * (1,2,3,4 = memory types)...
197 * Sample memory map (w/overlaps):
198 * ____22__________________
199 * ______________________4_
200 * ____1111________________
201 * _44_____________________
202 * 11111111________________
203 * ____________________33__
204 * ___________44___________
205 * __________33333_________
206 * ______________22________
207 * ___________________2222_
208 * _________111111111______
209 * _____________________11_
210 * _________________4______
212 * Sanitized equivalent (no overlap):
213 * 1_______________________
214 * _44_____________________
215 * ___1____________________
216 * ____22__________________
217 * ______11________________
218 * _________1______________
219 * __________3_____________
220 * ___________44___________
221 * _____________33_________
222 * _______________2________
223 * ________________1_______
224 * _________________4______
225 * ___________________2____
226 * ____________________33__
227 * ______________________4_
230 int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
231 u32 *pnr_map)
233 struct change_member {
234 struct e820entry *pbios; /* pointer to original bios entry */
235 unsigned long long addr; /* address for this change point */
237 static struct change_member change_point_list[2*E820_X_MAX] __initdata;
238 static struct change_member *change_point[2*E820_X_MAX] __initdata;
239 static struct e820entry *overlap_list[E820_X_MAX] __initdata;
240 static struct e820entry new_bios[E820_X_MAX] __initdata;
241 struct change_member *change_tmp;
242 unsigned long current_type, last_type;
243 unsigned long long last_addr;
244 int chgidx, still_changing;
245 int overlap_entries;
246 int new_bios_entry;
247 int old_nr, new_nr, chg_nr;
248 int i;
250 /* if there's only one memory region, don't bother */
251 if (*pnr_map < 2)
252 return -1;
254 old_nr = *pnr_map;
255 BUG_ON(old_nr > max_nr_map);
257 /* bail out if we find any unreasonable addresses in bios map */
258 for (i = 0; i < old_nr; i++)
259 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
260 return -1;
262 /* create pointers for initial change-point information (for sorting) */
263 for (i = 0; i < 2 * old_nr; i++)
264 change_point[i] = &change_point_list[i];
266 /* record all known change-points (starting and ending addresses),
267 omitting those that are for empty memory regions */
268 chgidx = 0;
269 for (i = 0; i < old_nr; i++) {
270 if (biosmap[i].size != 0) {
271 change_point[chgidx]->addr = biosmap[i].addr;
272 change_point[chgidx++]->pbios = &biosmap[i];
273 change_point[chgidx]->addr = biosmap[i].addr +
274 biosmap[i].size;
275 change_point[chgidx++]->pbios = &biosmap[i];
278 chg_nr = chgidx;
280 /* sort change-point list by memory addresses (low -> high) */
281 still_changing = 1;
282 while (still_changing) {
283 still_changing = 0;
284 for (i = 1; i < chg_nr; i++) {
285 unsigned long long curaddr, lastaddr;
286 unsigned long long curpbaddr, lastpbaddr;
288 curaddr = change_point[i]->addr;
289 lastaddr = change_point[i - 1]->addr;
290 curpbaddr = change_point[i]->pbios->addr;
291 lastpbaddr = change_point[i - 1]->pbios->addr;
294 * swap entries, when:
296 * curaddr > lastaddr or
297 * curaddr == lastaddr and curaddr == curpbaddr and
298 * lastaddr != lastpbaddr
300 if (curaddr < lastaddr ||
301 (curaddr == lastaddr && curaddr == curpbaddr &&
302 lastaddr != lastpbaddr)) {
303 change_tmp = change_point[i];
304 change_point[i] = change_point[i-1];
305 change_point[i-1] = change_tmp;
306 still_changing = 1;
311 /* create a new bios memory map, removing overlaps */
312 overlap_entries = 0; /* number of entries in the overlap table */
313 new_bios_entry = 0; /* index for creating new bios map entries */
314 last_type = 0; /* start with undefined memory type */
315 last_addr = 0; /* start with 0 as last starting address */
317 /* loop through change-points, determining affect on the new bios map */
318 for (chgidx = 0; chgidx < chg_nr; chgidx++) {
319 /* keep track of all overlapping bios entries */
320 if (change_point[chgidx]->addr ==
321 change_point[chgidx]->pbios->addr) {
323 * add map entry to overlap list (> 1 entry
324 * implies an overlap)
326 overlap_list[overlap_entries++] =
327 change_point[chgidx]->pbios;
328 } else {
330 * remove entry from list (order independent,
331 * so swap with last)
333 for (i = 0; i < overlap_entries; i++) {
334 if (overlap_list[i] ==
335 change_point[chgidx]->pbios)
336 overlap_list[i] =
337 overlap_list[overlap_entries-1];
339 overlap_entries--;
342 * if there are overlapping entries, decide which
343 * "type" to use (larger value takes precedence --
344 * 1=usable, 2,3,4,4+=unusable)
346 current_type = 0;
347 for (i = 0; i < overlap_entries; i++)
348 if (overlap_list[i]->type > current_type)
349 current_type = overlap_list[i]->type;
351 * continue building up new bios map based on this
352 * information
354 if (current_type != last_type) {
355 if (last_type != 0) {
356 new_bios[new_bios_entry].size =
357 change_point[chgidx]->addr - last_addr;
359 * move forward only if the new size
360 * was non-zero
362 if (new_bios[new_bios_entry].size != 0)
364 * no more space left for new
365 * bios entries ?
367 if (++new_bios_entry >= max_nr_map)
368 break;
370 if (current_type != 0) {
371 new_bios[new_bios_entry].addr =
372 change_point[chgidx]->addr;
373 new_bios[new_bios_entry].type = current_type;
374 last_addr = change_point[chgidx]->addr;
376 last_type = current_type;
379 /* retain count for new bios entries */
380 new_nr = new_bios_entry;
382 /* copy new bios mapping into original location */
383 memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
384 *pnr_map = new_nr;
386 return 0;
389 static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
391 while (nr_map) {
392 u64 start = biosmap->addr;
393 u64 size = biosmap->size;
394 u64 end = start + size;
395 u32 type = biosmap->type;
397 /* Overflow in 64 bits? Ignore the memory map. */
398 if (start > end)
399 return -1;
401 e820_add_region(start, size, type);
403 biosmap++;
404 nr_map--;
406 return 0;
410 * Copy the BIOS e820 map into a safe place.
412 * Sanity-check it while we're at it..
414 * If we're lucky and live on a modern system, the setup code
415 * will have given us a memory map that we can use to properly
416 * set up memory. If we aren't, we'll fake a memory map.
418 static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
420 /* Only one memory region (or negative)? Ignore it */
421 if (nr_map < 2)
422 return -1;
424 return __append_e820_map(biosmap, nr_map);
427 static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
428 u64 size, unsigned old_type,
429 unsigned new_type)
431 u64 end;
432 unsigned int i;
433 u64 real_updated_size = 0;
435 BUG_ON(old_type == new_type);
437 if (size > (ULLONG_MAX - start))
438 size = ULLONG_MAX - start;
440 end = start + size;
441 printk(KERN_DEBUG "e820 update range: %016Lx - %016Lx ",
442 (unsigned long long) start,
443 (unsigned long long) end);
444 e820_print_type(old_type);
445 printk(KERN_CONT " ==> ");
446 e820_print_type(new_type);
447 printk(KERN_CONT "\n");
449 for (i = 0; i < e820x->nr_map; i++) {
450 struct e820entry *ei = &e820x->map[i];
451 u64 final_start, final_end;
452 u64 ei_end;
454 if (ei->type != old_type)
455 continue;
457 ei_end = ei->addr + ei->size;
458 /* totally covered by new range? */
459 if (ei->addr >= start && ei_end <= end) {
460 ei->type = new_type;
461 real_updated_size += ei->size;
462 continue;
465 /* new range is totally covered? */
466 if (ei->addr < start && ei_end > end) {
467 __e820_add_region(e820x, start, size, new_type);
468 __e820_add_region(e820x, end, ei_end - end, ei->type);
469 ei->size = start - ei->addr;
470 real_updated_size += size;
471 continue;
474 /* partially covered */
475 final_start = max(start, ei->addr);
476 final_end = min(end, ei_end);
477 if (final_start >= final_end)
478 continue;
480 __e820_add_region(e820x, final_start, final_end - final_start,
481 new_type);
483 real_updated_size += final_end - final_start;
486 * left range could be head or tail, so need to update
487 * size at first.
489 ei->size -= final_end - final_start;
490 if (ei->addr < final_start)
491 continue;
492 ei->addr = final_end;
494 return real_updated_size;
497 u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
498 unsigned new_type)
500 return __e820_update_range(&e820, start, size, old_type, new_type);
503 static u64 __init e820_update_range_saved(u64 start, u64 size,
504 unsigned old_type, unsigned new_type)
506 return __e820_update_range(&e820_saved, start, size, old_type,
507 new_type);
510 /* make e820 not cover the range */
511 u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
512 int checktype)
514 int i;
515 u64 end;
516 u64 real_removed_size = 0;
518 if (size > (ULLONG_MAX - start))
519 size = ULLONG_MAX - start;
521 end = start + size;
522 printk(KERN_DEBUG "e820 remove range: %016Lx - %016Lx ",
523 (unsigned long long) start,
524 (unsigned long long) end);
525 if (checktype)
526 e820_print_type(old_type);
527 printk(KERN_CONT "\n");
529 for (i = 0; i < e820.nr_map; i++) {
530 struct e820entry *ei = &e820.map[i];
531 u64 final_start, final_end;
532 u64 ei_end;
534 if (checktype && ei->type != old_type)
535 continue;
537 ei_end = ei->addr + ei->size;
538 /* totally covered? */
539 if (ei->addr >= start && ei_end <= end) {
540 real_removed_size += ei->size;
541 memset(ei, 0, sizeof(struct e820entry));
542 continue;
545 /* new range is totally covered? */
546 if (ei->addr < start && ei_end > end) {
547 e820_add_region(end, ei_end - end, ei->type);
548 ei->size = start - ei->addr;
549 real_removed_size += size;
550 continue;
553 /* partially covered */
554 final_start = max(start, ei->addr);
555 final_end = min(end, ei_end);
556 if (final_start >= final_end)
557 continue;
558 real_removed_size += final_end - final_start;
561 * left range could be head or tail, so need to update
562 * size at first.
564 ei->size -= final_end - final_start;
565 if (ei->addr < final_start)
566 continue;
567 ei->addr = final_end;
569 return real_removed_size;
572 void __init update_e820(void)
574 u32 nr_map;
576 nr_map = e820.nr_map;
577 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr_map))
578 return;
579 e820.nr_map = nr_map;
580 printk(KERN_INFO "modified physical RAM map:\n");
581 e820_print_map("modified");
583 static void __init update_e820_saved(void)
585 u32 nr_map;
587 nr_map = e820_saved.nr_map;
588 if (sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map), &nr_map))
589 return;
590 e820_saved.nr_map = nr_map;
592 #define MAX_GAP_END 0x100000000ull
594 * Search for a gap in the e820 memory space from start_addr to end_addr.
596 __init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
597 unsigned long start_addr, unsigned long long end_addr)
599 unsigned long long last;
600 int i = e820.nr_map;
601 int found = 0;
603 last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
605 while (--i >= 0) {
606 unsigned long long start = e820.map[i].addr;
607 unsigned long long end = start + e820.map[i].size;
609 if (end < start_addr)
610 continue;
613 * Since "last" is at most 4GB, we know we'll
614 * fit in 32 bits if this condition is true
616 if (last > end) {
617 unsigned long gap = last - end;
619 if (gap >= *gapsize) {
620 *gapsize = gap;
621 *gapstart = end;
622 found = 1;
625 if (start < last)
626 last = start;
628 return found;
632 * Search for the biggest gap in the low 32 bits of the e820
633 * memory space. We pass this space to PCI to assign MMIO resources
634 * for hotplug or unconfigured devices in.
635 * Hopefully the BIOS let enough space left.
637 __init void e820_setup_gap(void)
639 unsigned long gapstart, gapsize;
640 int found;
642 gapstart = 0x10000000;
643 gapsize = 0x400000;
644 found = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
646 #ifdef CONFIG_X86_64
647 if (!found) {
648 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
649 printk(KERN_ERR
650 "PCI: Warning: Cannot find a gap in the 32bit address range\n"
651 "PCI: Unassigned devices with 32bit resource registers may break!\n");
653 #endif
656 * e820_reserve_resources_late protect stolen RAM already
658 pci_mem_start = gapstart;
660 printk(KERN_INFO
661 "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
662 pci_mem_start, gapstart, gapsize);
666 * Because of the size limitation of struct boot_params, only first
667 * 128 E820 memory entries are passed to kernel via
668 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
669 * linked list of struct setup_data, which is parsed here.
671 void __init parse_e820_ext(struct setup_data *sdata)
673 int entries;
674 struct e820entry *extmap;
676 entries = sdata->len / sizeof(struct e820entry);
677 extmap = (struct e820entry *)(sdata->data);
678 __append_e820_map(extmap, entries);
679 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
680 printk(KERN_INFO "extended physical RAM map:\n");
681 e820_print_map("extended");
684 #if defined(CONFIG_X86_64) || \
685 (defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
687 * Find the ranges of physical addresses that do not correspond to
688 * e820 RAM areas and mark the corresponding pages as nosave for
689 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
691 * This function requires the e820 map to be sorted and without any
692 * overlapping entries and assumes the first e820 area to be RAM.
694 void __init e820_mark_nosave_regions(unsigned long limit_pfn)
696 int i;
697 unsigned long pfn;
699 pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
700 for (i = 1; i < e820.nr_map; i++) {
701 struct e820entry *ei = &e820.map[i];
703 if (pfn < PFN_UP(ei->addr))
704 register_nosave_region(pfn, PFN_UP(ei->addr));
706 pfn = PFN_DOWN(ei->addr + ei->size);
707 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
708 register_nosave_region(PFN_UP(ei->addr), pfn);
710 if (pfn >= limit_pfn)
711 break;
714 #endif
716 #ifdef CONFIG_HIBERNATION
718 * Mark ACPI NVS memory region, so that we can save/restore it during
719 * hibernation and the subsequent resume.
721 static int __init e820_mark_nvs_memory(void)
723 int i;
725 for (i = 0; i < e820.nr_map; i++) {
726 struct e820entry *ei = &e820.map[i];
728 if (ei->type == E820_NVS)
729 suspend_nvs_register(ei->addr, ei->size);
732 return 0;
734 core_initcall(e820_mark_nvs_memory);
735 #endif
738 * pre allocated 4k and reserved it in memblock and e820_saved
740 u64 __init early_reserve_e820(u64 startt, u64 sizet, u64 align)
742 u64 size = 0;
743 u64 addr;
744 u64 start;
746 for (start = startt; ; start += size) {
747 start = memblock_x86_find_in_range_size(start, &size, align);
748 if (start == MEMBLOCK_ERROR)
749 return 0;
750 if (size >= sizet)
751 break;
754 #ifdef CONFIG_X86_32
755 if (start >= MAXMEM)
756 return 0;
757 if (start + size > MAXMEM)
758 size = MAXMEM - start;
759 #endif
761 addr = round_down(start + size - sizet, align);
762 if (addr < start)
763 return 0;
764 memblock_x86_reserve_range(addr, addr + sizet, "new next");
765 e820_update_range_saved(addr, sizet, E820_RAM, E820_RESERVED);
766 printk(KERN_INFO "update e820_saved for early_reserve_e820\n");
767 update_e820_saved();
769 return addr;
772 #ifdef CONFIG_X86_32
773 # ifdef CONFIG_X86_PAE
774 # define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
775 # else
776 # define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
777 # endif
778 #else /* CONFIG_X86_32 */
779 # define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
780 #endif
783 * Find the highest page frame number we have available
785 static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
787 int i;
788 unsigned long last_pfn = 0;
789 unsigned long max_arch_pfn = MAX_ARCH_PFN;
791 for (i = 0; i < e820.nr_map; i++) {
792 struct e820entry *ei = &e820.map[i];
793 unsigned long start_pfn;
794 unsigned long end_pfn;
796 if (ei->type != type)
797 continue;
799 start_pfn = ei->addr >> PAGE_SHIFT;
800 end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
802 if (start_pfn >= limit_pfn)
803 continue;
804 if (end_pfn > limit_pfn) {
805 last_pfn = limit_pfn;
806 break;
808 if (end_pfn > last_pfn)
809 last_pfn = end_pfn;
812 if (last_pfn > max_arch_pfn)
813 last_pfn = max_arch_pfn;
815 printk(KERN_INFO "last_pfn = %#lx max_arch_pfn = %#lx\n",
816 last_pfn, max_arch_pfn);
817 return last_pfn;
819 unsigned long __init e820_end_of_ram_pfn(void)
821 return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
824 unsigned long __init e820_end_of_low_ram_pfn(void)
826 return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
829 static void early_panic(char *msg)
831 early_printk(msg);
832 panic(msg);
835 static int userdef __initdata;
837 /* "mem=nopentium" disables the 4MB page tables. */
838 static int __init parse_memopt(char *p)
840 u64 mem_size;
842 if (!p)
843 return -EINVAL;
845 if (!strcmp(p, "nopentium")) {
846 #ifdef CONFIG_X86_32
847 setup_clear_cpu_cap(X86_FEATURE_PSE);
848 return 0;
849 #else
850 printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
851 return -EINVAL;
852 #endif
855 userdef = 1;
856 mem_size = memparse(p, &p);
857 /* don't remove all of memory when handling "mem={invalid}" param */
858 if (mem_size == 0)
859 return -EINVAL;
860 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
862 return 0;
864 early_param("mem", parse_memopt);
866 static int __init parse_memmap_opt(char *p)
868 char *oldp;
869 u64 start_at, mem_size;
871 if (!p)
872 return -EINVAL;
874 if (!strncmp(p, "exactmap", 8)) {
875 #ifdef CONFIG_CRASH_DUMP
877 * If we are doing a crash dump, we still need to know
878 * the real mem size before original memory map is
879 * reset.
881 saved_max_pfn = e820_end_of_ram_pfn();
882 #endif
883 e820.nr_map = 0;
884 userdef = 1;
885 return 0;
888 oldp = p;
889 mem_size = memparse(p, &p);
890 if (p == oldp)
891 return -EINVAL;
893 userdef = 1;
894 if (*p == '@') {
895 start_at = memparse(p+1, &p);
896 e820_add_region(start_at, mem_size, E820_RAM);
897 } else if (*p == '#') {
898 start_at = memparse(p+1, &p);
899 e820_add_region(start_at, mem_size, E820_ACPI);
900 } else if (*p == '$') {
901 start_at = memparse(p+1, &p);
902 e820_add_region(start_at, mem_size, E820_RESERVED);
903 } else
904 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
906 return *p == '\0' ? 0 : -EINVAL;
908 early_param("memmap", parse_memmap_opt);
910 void __init finish_e820_parsing(void)
912 if (userdef) {
913 u32 nr = e820.nr_map;
915 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
916 early_panic("Invalid user supplied memory map");
917 e820.nr_map = nr;
919 printk(KERN_INFO "user-defined physical RAM map:\n");
920 e820_print_map("user");
924 static inline const char *e820_type_to_string(int e820_type)
926 switch (e820_type) {
927 case E820_RESERVED_KERN:
928 case E820_RAM: return "System RAM";
929 case E820_ACPI: return "ACPI Tables";
930 case E820_NVS: return "ACPI Non-volatile Storage";
931 case E820_UNUSABLE: return "Unusable memory";
932 default: return "reserved";
937 * Mark e820 reserved areas as busy for the resource manager.
939 static struct resource __initdata *e820_res;
940 void __init e820_reserve_resources(void)
942 int i;
943 struct resource *res;
944 u64 end;
946 res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
947 e820_res = res;
948 for (i = 0; i < e820.nr_map; i++) {
949 end = e820.map[i].addr + e820.map[i].size - 1;
950 if (end != (resource_size_t)end) {
951 res++;
952 continue;
954 res->name = e820_type_to_string(e820.map[i].type);
955 res->start = e820.map[i].addr;
956 res->end = end;
958 res->flags = IORESOURCE_MEM;
961 * don't register the region that could be conflicted with
962 * pci device BAR resource and insert them later in
963 * pcibios_resource_survey()
965 if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
966 res->flags |= IORESOURCE_BUSY;
967 insert_resource(&iomem_resource, res);
969 res++;
972 for (i = 0; i < e820_saved.nr_map; i++) {
973 struct e820entry *entry = &e820_saved.map[i];
974 firmware_map_add_early(entry->addr,
975 entry->addr + entry->size - 1,
976 e820_type_to_string(entry->type));
980 /* How much should we pad RAM ending depending on where it is? */
981 static unsigned long ram_alignment(resource_size_t pos)
983 unsigned long mb = pos >> 20;
985 /* To 64kB in the first megabyte */
986 if (!mb)
987 return 64*1024;
989 /* To 1MB in the first 16MB */
990 if (mb < 16)
991 return 1024*1024;
993 /* To 64MB for anything above that */
994 return 64*1024*1024;
997 #define MAX_RESOURCE_SIZE ((resource_size_t)-1)
999 void __init e820_reserve_resources_late(void)
1001 int i;
1002 struct resource *res;
1004 res = e820_res;
1005 for (i = 0; i < e820.nr_map; i++) {
1006 if (!res->parent && res->end)
1007 insert_resource_expand_to_fit(&iomem_resource, res);
1008 res++;
1012 * Try to bump up RAM regions to reasonable boundaries to
1013 * avoid stolen RAM:
1015 for (i = 0; i < e820.nr_map; i++) {
1016 struct e820entry *entry = &e820.map[i];
1017 u64 start, end;
1019 if (entry->type != E820_RAM)
1020 continue;
1021 start = entry->addr + entry->size;
1022 end = round_up(start, ram_alignment(start)) - 1;
1023 if (end > MAX_RESOURCE_SIZE)
1024 end = MAX_RESOURCE_SIZE;
1025 if (start >= end)
1026 continue;
1027 printk(KERN_DEBUG "reserve RAM buffer: %016llx - %016llx ",
1028 start, end);
1029 reserve_region_with_split(&iomem_resource, start, end,
1030 "RAM buffer");
1034 char *__init default_machine_specific_memory_setup(void)
1036 char *who = "BIOS-e820";
1037 u32 new_nr;
1039 * Try to copy the BIOS-supplied E820-map.
1041 * Otherwise fake a memory map; one section from 0k->640k,
1042 * the next section from 1mb->appropriate_mem_k
1044 new_nr = boot_params.e820_entries;
1045 sanitize_e820_map(boot_params.e820_map,
1046 ARRAY_SIZE(boot_params.e820_map),
1047 &new_nr);
1048 boot_params.e820_entries = new_nr;
1049 if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1050 < 0) {
1051 u64 mem_size;
1053 /* compare results from other methods and take the greater */
1054 if (boot_params.alt_mem_k
1055 < boot_params.screen_info.ext_mem_k) {
1056 mem_size = boot_params.screen_info.ext_mem_k;
1057 who = "BIOS-88";
1058 } else {
1059 mem_size = boot_params.alt_mem_k;
1060 who = "BIOS-e801";
1063 e820.nr_map = 0;
1064 e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1065 e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1068 /* In case someone cares... */
1069 return who;
1072 void __init setup_memory_map(void)
1074 char *who;
1076 who = x86_init.resources.memory_setup();
1077 memcpy(&e820_saved, &e820, sizeof(struct e820map));
1078 printk(KERN_INFO "BIOS-provided physical RAM map:\n");
1079 e820_print_map(who);
1082 void __init memblock_x86_fill(void)
1084 int i;
1085 u64 end;
1088 * EFI may have more than 128 entries
1089 * We are safe to enable resizing, beause memblock_x86_fill()
1090 * is rather later for x86
1092 memblock_can_resize = 1;
1094 for (i = 0; i < e820.nr_map; i++) {
1095 struct e820entry *ei = &e820.map[i];
1097 end = ei->addr + ei->size;
1098 if (end != (resource_size_t)end)
1099 continue;
1101 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
1102 continue;
1104 memblock_add(ei->addr, ei->size);
1107 memblock_analyze();
1108 memblock_dump_all();
1111 void __init memblock_find_dma_reserve(void)
1113 #ifdef CONFIG_X86_64
1114 u64 free_size_pfn;
1115 u64 mem_size_pfn;
1117 * need to find out used area below MAX_DMA_PFN
1118 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1119 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1121 mem_size_pfn = memblock_x86_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT;
1122 free_size_pfn = memblock_x86_free_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT;
1123 set_dma_reserve(mem_size_pfn - free_size_pfn);
1124 #endif