xhci: Clean up 32-bit build warnings.
[zen-stable.git] / arch / x86 / kernel / e820.c
blob65ffd110a81bc95491fb13ae7c87cd7be1738f93
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/export.h>
16 #include <linux/bootmem.h>
17 #include <linux/pfn.h>
18 #include <linux/suspend.h>
19 #include <linux/acpi.h>
20 #include <linux/firmware-map.h>
21 #include <linux/memblock.h>
23 #include <asm/e820.h>
24 #include <asm/proto.h>
25 #include <asm/setup.h>
28 * The e820 map is the map that gets modified e.g. with command line parameters
29 * and that is also registered with modifications in the kernel resource tree
30 * with the iomem_resource as parent.
32 * The e820_saved is directly saved after the BIOS-provided memory map is
33 * copied. It doesn't get modified afterwards. It's registered for the
34 * /sys/firmware/memmap interface.
36 * That memory map is not modified and is used as base for kexec. The kexec'd
37 * kernel should get the same memory map as the firmware provides. Then the
38 * user can e.g. boot the original kernel with mem=1G while still booting the
39 * next kernel with full memory.
41 struct e820map e820;
42 struct e820map e820_saved;
44 /* For PCI or other memory-mapped resources */
45 unsigned long pci_mem_start = 0xaeedbabe;
46 #ifdef CONFIG_PCI
47 EXPORT_SYMBOL(pci_mem_start);
48 #endif
51 * This function checks if any part of the range <start,end> is mapped
52 * with type.
54 int
55 e820_any_mapped(u64 start, u64 end, unsigned type)
57 int i;
59 for (i = 0; i < e820.nr_map; i++) {
60 struct e820entry *ei = &e820.map[i];
62 if (type && ei->type != type)
63 continue;
64 if (ei->addr >= end || ei->addr + ei->size <= start)
65 continue;
66 return 1;
68 return 0;
70 EXPORT_SYMBOL_GPL(e820_any_mapped);
73 * This function checks if the entire range <start,end> is mapped with type.
75 * Note: this function only works correct if the e820 table is sorted and
76 * not-overlapping, which is the case
78 int __init e820_all_mapped(u64 start, u64 end, unsigned type)
80 int i;
82 for (i = 0; i < e820.nr_map; i++) {
83 struct e820entry *ei = &e820.map[i];
85 if (type && ei->type != type)
86 continue;
87 /* is the region (part) in overlap with the current region ?*/
88 if (ei->addr >= end || ei->addr + ei->size <= start)
89 continue;
91 /* if the region is at the beginning of <start,end> we move
92 * start to the end of the region since it's ok until there
94 if (ei->addr <= start)
95 start = ei->addr + ei->size;
97 * if start is now at or beyond end, we're done, full
98 * coverage
100 if (start >= end)
101 return 1;
103 return 0;
107 * Add a memory region to the kernel e820 map.
109 static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
110 int type)
112 int x = e820x->nr_map;
114 if (x >= ARRAY_SIZE(e820x->map)) {
115 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
116 return;
119 e820x->map[x].addr = start;
120 e820x->map[x].size = size;
121 e820x->map[x].type = type;
122 e820x->nr_map++;
125 void __init e820_add_region(u64 start, u64 size, int type)
127 __e820_add_region(&e820, start, size, type);
130 static void __init e820_print_type(u32 type)
132 switch (type) {
133 case E820_RAM:
134 case E820_RESERVED_KERN:
135 printk(KERN_CONT "(usable)");
136 break;
137 case E820_RESERVED:
138 case E820_RESERVED_EFI:
139 printk(KERN_CONT "(reserved)");
140 break;
141 case E820_ACPI:
142 printk(KERN_CONT "(ACPI data)");
143 break;
144 case E820_NVS:
145 printk(KERN_CONT "(ACPI NVS)");
146 break;
147 case E820_UNUSABLE:
148 printk(KERN_CONT "(unusable)");
149 break;
150 default:
151 printk(KERN_CONT "type %u", type);
152 break;
156 void __init e820_print_map(char *who)
158 int i;
160 for (i = 0; i < e820.nr_map; i++) {
161 printk(KERN_INFO " %s: %016Lx - %016Lx ", who,
162 (unsigned long long) e820.map[i].addr,
163 (unsigned long long)
164 (e820.map[i].addr + e820.map[i].size));
165 e820_print_type(e820.map[i].type);
166 printk(KERN_CONT "\n");
171 * Sanitize the BIOS e820 map.
173 * Some e820 responses include overlapping entries. The following
174 * replaces the original e820 map with a new one, removing overlaps,
175 * and resolving conflicting memory types in favor of highest
176 * numbered type.
178 * The input parameter biosmap points to an array of 'struct
179 * e820entry' which on entry has elements in the range [0, *pnr_map)
180 * valid, and which has space for up to max_nr_map entries.
181 * On return, the resulting sanitized e820 map entries will be in
182 * overwritten in the same location, starting at biosmap.
184 * The integer pointed to by pnr_map must be valid on entry (the
185 * current number of valid entries located at biosmap) and will
186 * be updated on return, with the new number of valid entries
187 * (something no more than max_nr_map.)
189 * The return value from sanitize_e820_map() is zero if it
190 * successfully 'sanitized' the map entries passed in, and is -1
191 * if it did nothing, which can happen if either of (1) it was
192 * only passed one map entry, or (2) any of the input map entries
193 * were invalid (start + size < start, meaning that the size was
194 * so big the described memory range wrapped around through zero.)
196 * Visually we're performing the following
197 * (1,2,3,4 = memory types)...
199 * Sample memory map (w/overlaps):
200 * ____22__________________
201 * ______________________4_
202 * ____1111________________
203 * _44_____________________
204 * 11111111________________
205 * ____________________33__
206 * ___________44___________
207 * __________33333_________
208 * ______________22________
209 * ___________________2222_
210 * _________111111111______
211 * _____________________11_
212 * _________________4______
214 * Sanitized equivalent (no overlap):
215 * 1_______________________
216 * _44_____________________
217 * ___1____________________
218 * ____22__________________
219 * ______11________________
220 * _________1______________
221 * __________3_____________
222 * ___________44___________
223 * _____________33_________
224 * _______________2________
225 * ________________1_______
226 * _________________4______
227 * ___________________2____
228 * ____________________33__
229 * ______________________4_
232 int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
233 u32 *pnr_map)
235 struct change_member {
236 struct e820entry *pbios; /* pointer to original bios entry */
237 unsigned long long addr; /* address for this change point */
239 static struct change_member change_point_list[2*E820_X_MAX] __initdata;
240 static struct change_member *change_point[2*E820_X_MAX] __initdata;
241 static struct e820entry *overlap_list[E820_X_MAX] __initdata;
242 static struct e820entry new_bios[E820_X_MAX] __initdata;
243 struct change_member *change_tmp;
244 unsigned long current_type, last_type;
245 unsigned long long last_addr;
246 int chgidx, still_changing;
247 int overlap_entries;
248 int new_bios_entry;
249 int old_nr, new_nr, chg_nr;
250 int i;
252 /* if there's only one memory region, don't bother */
253 if (*pnr_map < 2)
254 return -1;
256 old_nr = *pnr_map;
257 BUG_ON(old_nr > max_nr_map);
259 /* bail out if we find any unreasonable addresses in bios map */
260 for (i = 0; i < old_nr; i++)
261 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
262 return -1;
264 /* create pointers for initial change-point information (for sorting) */
265 for (i = 0; i < 2 * old_nr; i++)
266 change_point[i] = &change_point_list[i];
268 /* record all known change-points (starting and ending addresses),
269 omitting those that are for empty memory regions */
270 chgidx = 0;
271 for (i = 0; i < old_nr; i++) {
272 if (biosmap[i].size != 0) {
273 change_point[chgidx]->addr = biosmap[i].addr;
274 change_point[chgidx++]->pbios = &biosmap[i];
275 change_point[chgidx]->addr = biosmap[i].addr +
276 biosmap[i].size;
277 change_point[chgidx++]->pbios = &biosmap[i];
280 chg_nr = chgidx;
282 /* sort change-point list by memory addresses (low -> high) */
283 still_changing = 1;
284 while (still_changing) {
285 still_changing = 0;
286 for (i = 1; i < chg_nr; i++) {
287 unsigned long long curaddr, lastaddr;
288 unsigned long long curpbaddr, lastpbaddr;
290 curaddr = change_point[i]->addr;
291 lastaddr = change_point[i - 1]->addr;
292 curpbaddr = change_point[i]->pbios->addr;
293 lastpbaddr = change_point[i - 1]->pbios->addr;
296 * swap entries, when:
298 * curaddr > lastaddr or
299 * curaddr == lastaddr and curaddr == curpbaddr and
300 * lastaddr != lastpbaddr
302 if (curaddr < lastaddr ||
303 (curaddr == lastaddr && curaddr == curpbaddr &&
304 lastaddr != lastpbaddr)) {
305 change_tmp = change_point[i];
306 change_point[i] = change_point[i-1];
307 change_point[i-1] = change_tmp;
308 still_changing = 1;
313 /* create a new bios memory map, removing overlaps */
314 overlap_entries = 0; /* number of entries in the overlap table */
315 new_bios_entry = 0; /* index for creating new bios map entries */
316 last_type = 0; /* start with undefined memory type */
317 last_addr = 0; /* start with 0 as last starting address */
319 /* loop through change-points, determining affect on the new bios map */
320 for (chgidx = 0; chgidx < chg_nr; chgidx++) {
321 /* keep track of all overlapping bios entries */
322 if (change_point[chgidx]->addr ==
323 change_point[chgidx]->pbios->addr) {
325 * add map entry to overlap list (> 1 entry
326 * implies an overlap)
328 overlap_list[overlap_entries++] =
329 change_point[chgidx]->pbios;
330 } else {
332 * remove entry from list (order independent,
333 * so swap with last)
335 for (i = 0; i < overlap_entries; i++) {
336 if (overlap_list[i] ==
337 change_point[chgidx]->pbios)
338 overlap_list[i] =
339 overlap_list[overlap_entries-1];
341 overlap_entries--;
344 * if there are overlapping entries, decide which
345 * "type" to use (larger value takes precedence --
346 * 1=usable, 2,3,4,4+=unusable)
348 current_type = 0;
349 for (i = 0; i < overlap_entries; i++)
350 if (overlap_list[i]->type > current_type)
351 current_type = overlap_list[i]->type;
353 * continue building up new bios map based on this
354 * information
356 if (current_type != last_type) {
357 if (last_type != 0) {
358 new_bios[new_bios_entry].size =
359 change_point[chgidx]->addr - last_addr;
361 * move forward only if the new size
362 * was non-zero
364 if (new_bios[new_bios_entry].size != 0)
366 * no more space left for new
367 * bios entries ?
369 if (++new_bios_entry >= max_nr_map)
370 break;
372 if (current_type != 0) {
373 new_bios[new_bios_entry].addr =
374 change_point[chgidx]->addr;
375 new_bios[new_bios_entry].type = current_type;
376 last_addr = change_point[chgidx]->addr;
378 last_type = current_type;
381 /* retain count for new bios entries */
382 new_nr = new_bios_entry;
384 /* copy new bios mapping into original location */
385 memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
386 *pnr_map = new_nr;
388 return 0;
391 static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
393 while (nr_map) {
394 u64 start = biosmap->addr;
395 u64 size = biosmap->size;
396 u64 end = start + size;
397 u32 type = biosmap->type;
399 /* Overflow in 64 bits? Ignore the memory map. */
400 if (start > end)
401 return -1;
403 e820_add_region(start, size, type);
405 biosmap++;
406 nr_map--;
408 return 0;
412 * Copy the BIOS e820 map into a safe place.
414 * Sanity-check it while we're at it..
416 * If we're lucky and live on a modern system, the setup code
417 * will have given us a memory map that we can use to properly
418 * set up memory. If we aren't, we'll fake a memory map.
420 static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
422 /* Only one memory region (or negative)? Ignore it */
423 if (nr_map < 2)
424 return -1;
426 return __append_e820_map(biosmap, nr_map);
429 static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
430 u64 size, unsigned old_type,
431 unsigned new_type)
433 u64 end;
434 unsigned int i;
435 u64 real_updated_size = 0;
437 BUG_ON(old_type == new_type);
439 if (size > (ULLONG_MAX - start))
440 size = ULLONG_MAX - start;
442 end = start + size;
443 printk(KERN_DEBUG "e820 update range: %016Lx - %016Lx ",
444 (unsigned long long) start,
445 (unsigned long long) end);
446 e820_print_type(old_type);
447 printk(KERN_CONT " ==> ");
448 e820_print_type(new_type);
449 printk(KERN_CONT "\n");
451 for (i = 0; i < e820x->nr_map; i++) {
452 struct e820entry *ei = &e820x->map[i];
453 u64 final_start, final_end;
454 u64 ei_end;
456 if (ei->type != old_type)
457 continue;
459 ei_end = ei->addr + ei->size;
460 /* totally covered by new range? */
461 if (ei->addr >= start && ei_end <= end) {
462 ei->type = new_type;
463 real_updated_size += ei->size;
464 continue;
467 /* new range is totally covered? */
468 if (ei->addr < start && ei_end > end) {
469 __e820_add_region(e820x, start, size, new_type);
470 __e820_add_region(e820x, end, ei_end - end, ei->type);
471 ei->size = start - ei->addr;
472 real_updated_size += size;
473 continue;
476 /* partially covered */
477 final_start = max(start, ei->addr);
478 final_end = min(end, ei_end);
479 if (final_start >= final_end)
480 continue;
482 __e820_add_region(e820x, final_start, final_end - final_start,
483 new_type);
485 real_updated_size += final_end - final_start;
488 * left range could be head or tail, so need to update
489 * size at first.
491 ei->size -= final_end - final_start;
492 if (ei->addr < final_start)
493 continue;
494 ei->addr = final_end;
496 return real_updated_size;
499 u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
500 unsigned new_type)
502 return __e820_update_range(&e820, start, size, old_type, new_type);
505 static u64 __init e820_update_range_saved(u64 start, u64 size,
506 unsigned old_type, unsigned new_type)
508 return __e820_update_range(&e820_saved, start, size, old_type,
509 new_type);
512 /* make e820 not cover the range */
513 u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
514 int checktype)
516 int i;
517 u64 end;
518 u64 real_removed_size = 0;
520 if (size > (ULLONG_MAX - start))
521 size = ULLONG_MAX - start;
523 end = start + size;
524 printk(KERN_DEBUG "e820 remove range: %016Lx - %016Lx ",
525 (unsigned long long) start,
526 (unsigned long long) end);
527 if (checktype)
528 e820_print_type(old_type);
529 printk(KERN_CONT "\n");
531 for (i = 0; i < e820.nr_map; i++) {
532 struct e820entry *ei = &e820.map[i];
533 u64 final_start, final_end;
534 u64 ei_end;
536 if (checktype && ei->type != old_type)
537 continue;
539 ei_end = ei->addr + ei->size;
540 /* totally covered? */
541 if (ei->addr >= start && ei_end <= end) {
542 real_removed_size += ei->size;
543 memset(ei, 0, sizeof(struct e820entry));
544 continue;
547 /* new range is totally covered? */
548 if (ei->addr < start && ei_end > end) {
549 e820_add_region(end, ei_end - end, ei->type);
550 ei->size = start - ei->addr;
551 real_removed_size += size;
552 continue;
555 /* partially covered */
556 final_start = max(start, ei->addr);
557 final_end = min(end, ei_end);
558 if (final_start >= final_end)
559 continue;
560 real_removed_size += final_end - final_start;
563 * left range could be head or tail, so need to update
564 * size at first.
566 ei->size -= final_end - final_start;
567 if (ei->addr < final_start)
568 continue;
569 ei->addr = final_end;
571 return real_removed_size;
574 void __init update_e820(void)
576 u32 nr_map;
578 nr_map = e820.nr_map;
579 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr_map))
580 return;
581 e820.nr_map = nr_map;
582 printk(KERN_INFO "modified physical RAM map:\n");
583 e820_print_map("modified");
585 static void __init update_e820_saved(void)
587 u32 nr_map;
589 nr_map = e820_saved.nr_map;
590 if (sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map), &nr_map))
591 return;
592 e820_saved.nr_map = nr_map;
594 #define MAX_GAP_END 0x100000000ull
596 * Search for a gap in the e820 memory space from start_addr to end_addr.
598 __init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
599 unsigned long start_addr, unsigned long long end_addr)
601 unsigned long long last;
602 int i = e820.nr_map;
603 int found = 0;
605 last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
607 while (--i >= 0) {
608 unsigned long long start = e820.map[i].addr;
609 unsigned long long end = start + e820.map[i].size;
611 if (end < start_addr)
612 continue;
615 * Since "last" is at most 4GB, we know we'll
616 * fit in 32 bits if this condition is true
618 if (last > end) {
619 unsigned long gap = last - end;
621 if (gap >= *gapsize) {
622 *gapsize = gap;
623 *gapstart = end;
624 found = 1;
627 if (start < last)
628 last = start;
630 return found;
634 * Search for the biggest gap in the low 32 bits of the e820
635 * memory space. We pass this space to PCI to assign MMIO resources
636 * for hotplug or unconfigured devices in.
637 * Hopefully the BIOS let enough space left.
639 __init void e820_setup_gap(void)
641 unsigned long gapstart, gapsize;
642 int found;
644 gapstart = 0x10000000;
645 gapsize = 0x400000;
646 found = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
648 #ifdef CONFIG_X86_64
649 if (!found) {
650 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
651 printk(KERN_ERR
652 "PCI: Warning: Cannot find a gap in the 32bit address range\n"
653 "PCI: Unassigned devices with 32bit resource registers may break!\n");
655 #endif
658 * e820_reserve_resources_late protect stolen RAM already
660 pci_mem_start = gapstart;
662 printk(KERN_INFO
663 "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
664 pci_mem_start, gapstart, gapsize);
668 * Because of the size limitation of struct boot_params, only first
669 * 128 E820 memory entries are passed to kernel via
670 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
671 * linked list of struct setup_data, which is parsed here.
673 void __init parse_e820_ext(struct setup_data *sdata)
675 int entries;
676 struct e820entry *extmap;
678 entries = sdata->len / sizeof(struct e820entry);
679 extmap = (struct e820entry *)(sdata->data);
680 __append_e820_map(extmap, entries);
681 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
682 printk(KERN_INFO "extended physical RAM map:\n");
683 e820_print_map("extended");
686 #if defined(CONFIG_X86_64) || \
687 (defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
689 * Find the ranges of physical addresses that do not correspond to
690 * e820 RAM areas and mark the corresponding pages as nosave for
691 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
693 * This function requires the e820 map to be sorted and without any
694 * overlapping entries and assumes the first e820 area to be RAM.
696 void __init e820_mark_nosave_regions(unsigned long limit_pfn)
698 int i;
699 unsigned long pfn;
701 pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
702 for (i = 1; i < e820.nr_map; i++) {
703 struct e820entry *ei = &e820.map[i];
705 if (pfn < PFN_UP(ei->addr))
706 register_nosave_region(pfn, PFN_UP(ei->addr));
708 pfn = PFN_DOWN(ei->addr + ei->size);
709 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
710 register_nosave_region(PFN_UP(ei->addr), pfn);
712 if (pfn >= limit_pfn)
713 break;
716 #endif
718 #ifdef CONFIG_HIBERNATION
720 * Mark ACPI NVS memory region, so that we can save/restore it during
721 * hibernation and the subsequent resume.
723 static int __init e820_mark_nvs_memory(void)
725 int i;
727 for (i = 0; i < e820.nr_map; i++) {
728 struct e820entry *ei = &e820.map[i];
730 if (ei->type == E820_NVS)
731 suspend_nvs_register(ei->addr, ei->size);
734 return 0;
736 core_initcall(e820_mark_nvs_memory);
737 #endif
740 * pre allocated 4k and reserved it in memblock and e820_saved
742 u64 __init early_reserve_e820(u64 startt, u64 sizet, u64 align)
744 u64 size = 0;
745 u64 addr;
746 u64 start;
748 for (start = startt; ; start += size) {
749 start = memblock_x86_find_in_range_size(start, &size, align);
750 if (start == MEMBLOCK_ERROR)
751 return 0;
752 if (size >= sizet)
753 break;
756 #ifdef CONFIG_X86_32
757 if (start >= MAXMEM)
758 return 0;
759 if (start + size > MAXMEM)
760 size = MAXMEM - start;
761 #endif
763 addr = round_down(start + size - sizet, align);
764 if (addr < start)
765 return 0;
766 memblock_x86_reserve_range(addr, addr + sizet, "new next");
767 e820_update_range_saved(addr, sizet, E820_RAM, E820_RESERVED);
768 printk(KERN_INFO "update e820_saved for early_reserve_e820\n");
769 update_e820_saved();
771 return addr;
774 #ifdef CONFIG_X86_32
775 # ifdef CONFIG_X86_PAE
776 # define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
777 # else
778 # define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
779 # endif
780 #else /* CONFIG_X86_32 */
781 # define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
782 #endif
785 * Find the highest page frame number we have available
787 unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
789 int i;
790 unsigned long last_pfn = 0;
791 unsigned long max_arch_pfn = MAX_ARCH_PFN;
793 for (i = 0; i < e820.nr_map; i++) {
794 struct e820entry *ei = &e820.map[i];
795 unsigned long start_pfn;
796 unsigned long end_pfn;
798 if (ei->type != type)
799 continue;
801 start_pfn = ei->addr >> PAGE_SHIFT;
802 end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
804 if (start_pfn >= limit_pfn)
805 continue;
806 if (end_pfn > limit_pfn) {
807 last_pfn = limit_pfn;
808 break;
810 if (end_pfn > last_pfn)
811 last_pfn = end_pfn;
814 if (last_pfn > max_arch_pfn)
815 last_pfn = max_arch_pfn;
817 printk(KERN_INFO "last_pfn = %#lx max_arch_pfn = %#lx\n",
818 last_pfn, max_arch_pfn);
819 return last_pfn;
821 unsigned long __init e820_end_of_ram_pfn(void)
823 return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
826 unsigned long __init e820_end_of_low_ram_pfn(void)
828 return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
831 static void early_panic(char *msg)
833 early_printk(msg);
834 panic(msg);
837 static int userdef __initdata;
839 /* "mem=nopentium" disables the 4MB page tables. */
840 static int __init parse_memopt(char *p)
842 u64 mem_size;
844 if (!p)
845 return -EINVAL;
847 if (!strcmp(p, "nopentium")) {
848 #ifdef CONFIG_X86_32
849 setup_clear_cpu_cap(X86_FEATURE_PSE);
850 return 0;
851 #else
852 printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
853 return -EINVAL;
854 #endif
857 userdef = 1;
858 mem_size = memparse(p, &p);
859 /* don't remove all of memory when handling "mem={invalid}" param */
860 if (mem_size == 0)
861 return -EINVAL;
862 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
864 return 0;
866 early_param("mem", parse_memopt);
868 static int __init parse_memmap_opt(char *p)
870 char *oldp;
871 u64 start_at, mem_size;
873 if (!p)
874 return -EINVAL;
876 if (!strncmp(p, "exactmap", 8)) {
877 #ifdef CONFIG_CRASH_DUMP
879 * If we are doing a crash dump, we still need to know
880 * the real mem size before original memory map is
881 * reset.
883 saved_max_pfn = e820_end_of_ram_pfn();
884 #endif
885 e820.nr_map = 0;
886 userdef = 1;
887 return 0;
890 oldp = p;
891 mem_size = memparse(p, &p);
892 if (p == oldp)
893 return -EINVAL;
895 userdef = 1;
896 if (*p == '@') {
897 start_at = memparse(p+1, &p);
898 e820_add_region(start_at, mem_size, E820_RAM);
899 } else if (*p == '#') {
900 start_at = memparse(p+1, &p);
901 e820_add_region(start_at, mem_size, E820_ACPI);
902 } else if (*p == '$') {
903 start_at = memparse(p+1, &p);
904 e820_add_region(start_at, mem_size, E820_RESERVED);
905 } else
906 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
908 return *p == '\0' ? 0 : -EINVAL;
910 early_param("memmap", parse_memmap_opt);
912 void __init finish_e820_parsing(void)
914 if (userdef) {
915 u32 nr = e820.nr_map;
917 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
918 early_panic("Invalid user supplied memory map");
919 e820.nr_map = nr;
921 printk(KERN_INFO "user-defined physical RAM map:\n");
922 e820_print_map("user");
926 static inline const char *e820_type_to_string(int e820_type)
928 switch (e820_type) {
929 case E820_RESERVED_KERN:
930 case E820_RAM: return "System RAM";
931 case E820_ACPI: return "ACPI Tables";
932 case E820_NVS: return "ACPI Non-volatile Storage";
933 case E820_UNUSABLE: return "Unusable memory";
934 default: return "reserved";
939 * Mark e820 reserved areas as busy for the resource manager.
941 static struct resource __initdata *e820_res;
942 void __init e820_reserve_resources(void)
944 int i;
945 struct resource *res;
946 u64 end;
948 res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
949 e820_res = res;
950 for (i = 0; i < e820.nr_map; i++) {
951 end = e820.map[i].addr + e820.map[i].size - 1;
952 if (end != (resource_size_t)end) {
953 res++;
954 continue;
956 res->name = e820_type_to_string(e820.map[i].type);
957 res->start = e820.map[i].addr;
958 res->end = end;
960 res->flags = IORESOURCE_MEM;
963 * don't register the region that could be conflicted with
964 * pci device BAR resource and insert them later in
965 * pcibios_resource_survey()
967 if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
968 res->flags |= IORESOURCE_BUSY;
969 insert_resource(&iomem_resource, res);
971 res++;
974 for (i = 0; i < e820_saved.nr_map; i++) {
975 struct e820entry *entry = &e820_saved.map[i];
976 firmware_map_add_early(entry->addr,
977 entry->addr + entry->size - 1,
978 e820_type_to_string(entry->type));
982 /* How much should we pad RAM ending depending on where it is? */
983 static unsigned long ram_alignment(resource_size_t pos)
985 unsigned long mb = pos >> 20;
987 /* To 64kB in the first megabyte */
988 if (!mb)
989 return 64*1024;
991 /* To 1MB in the first 16MB */
992 if (mb < 16)
993 return 1024*1024;
995 /* To 64MB for anything above that */
996 return 64*1024*1024;
999 #define MAX_RESOURCE_SIZE ((resource_size_t)-1)
1001 void __init e820_reserve_resources_late(void)
1003 int i;
1004 struct resource *res;
1006 res = e820_res;
1007 for (i = 0; i < e820.nr_map; i++) {
1008 if (!res->parent && res->end)
1009 insert_resource_expand_to_fit(&iomem_resource, res);
1010 res++;
1014 * Try to bump up RAM regions to reasonable boundaries to
1015 * avoid stolen RAM:
1017 for (i = 0; i < e820.nr_map; i++) {
1018 struct e820entry *entry = &e820.map[i];
1019 u64 start, end;
1021 if (entry->type != E820_RAM)
1022 continue;
1023 start = entry->addr + entry->size;
1024 end = round_up(start, ram_alignment(start)) - 1;
1025 if (end > MAX_RESOURCE_SIZE)
1026 end = MAX_RESOURCE_SIZE;
1027 if (start >= end)
1028 continue;
1029 printk(KERN_DEBUG "reserve RAM buffer: %016llx - %016llx ",
1030 start, end);
1031 reserve_region_with_split(&iomem_resource, start, end,
1032 "RAM buffer");
1036 char *__init default_machine_specific_memory_setup(void)
1038 char *who = "BIOS-e820";
1039 u32 new_nr;
1041 * Try to copy the BIOS-supplied E820-map.
1043 * Otherwise fake a memory map; one section from 0k->640k,
1044 * the next section from 1mb->appropriate_mem_k
1046 new_nr = boot_params.e820_entries;
1047 sanitize_e820_map(boot_params.e820_map,
1048 ARRAY_SIZE(boot_params.e820_map),
1049 &new_nr);
1050 boot_params.e820_entries = new_nr;
1051 if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1052 < 0) {
1053 u64 mem_size;
1055 /* compare results from other methods and take the greater */
1056 if (boot_params.alt_mem_k
1057 < boot_params.screen_info.ext_mem_k) {
1058 mem_size = boot_params.screen_info.ext_mem_k;
1059 who = "BIOS-88";
1060 } else {
1061 mem_size = boot_params.alt_mem_k;
1062 who = "BIOS-e801";
1065 e820.nr_map = 0;
1066 e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1067 e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1070 /* In case someone cares... */
1071 return who;
1074 void __init setup_memory_map(void)
1076 char *who;
1078 who = x86_init.resources.memory_setup();
1079 memcpy(&e820_saved, &e820, sizeof(struct e820map));
1080 printk(KERN_INFO "BIOS-provided physical RAM map:\n");
1081 e820_print_map(who);
1084 void __init memblock_x86_fill(void)
1086 int i;
1087 u64 end;
1090 * EFI may have more than 128 entries
1091 * We are safe to enable resizing, beause memblock_x86_fill()
1092 * is rather later for x86
1094 memblock_can_resize = 1;
1096 for (i = 0; i < e820.nr_map; i++) {
1097 struct e820entry *ei = &e820.map[i];
1099 end = ei->addr + ei->size;
1100 if (end != (resource_size_t)end)
1101 continue;
1103 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
1104 continue;
1106 memblock_add(ei->addr, ei->size);
1109 memblock_analyze();
1110 memblock_dump_all();
1113 void __init memblock_find_dma_reserve(void)
1115 #ifdef CONFIG_X86_64
1116 u64 free_size_pfn;
1117 u64 mem_size_pfn;
1119 * need to find out used area below MAX_DMA_PFN
1120 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1121 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1123 mem_size_pfn = memblock_x86_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT;
1124 free_size_pfn = memblock_x86_free_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT;
1125 set_dma_reserve(mem_size_pfn - free_size_pfn);
1126 #endif