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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Handle the memory map.
3 * The functions here do the job until bootmem takes over.
Venkatesh Pallipadi8059b2a2005-05-01 08:58:52 -07004 *
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>
9 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/kernel.h>
12#include <linux/types.h>
13#include <linux/init.h>
14#include <linux/bootmem.h>
15#include <linux/ioport.h>
16#include <linux/string.h>
Eric W. Biederman5f5609d2005-06-25 14:58:04 -070017#include <linux/kexec.h>
Andrew Mortonb9491ac2005-09-16 19:27:54 -070018#include <linux/module.h>
Rafael J. Wysockie8eff5a2006-09-25 23:32:46 -070019#include <linux/mm.h>
Andrew Mortonb9491ac2005-09-16 19:27:54 -070020
Andrew Morton1a91023a2006-07-10 04:43:49 -070021#include <asm/pgtable.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <asm/page.h>
23#include <asm/e820.h>
24#include <asm/proto.h>
25#include <asm/bootsetup.h>
Andi Kleen2bc04142005-11-05 17:25:53 +010026#include <asm/sections.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027
Andi Kleen3bd4d182006-09-26 10:52:33 +020028struct e820map e820 __initdata;
29
Linus Torvalds1da177e2005-04-16 15:20:36 -070030/*
31 * PFN of last memory page.
32 */
33unsigned long end_pfn;
Andi Kleenf3591ff2005-09-13 11:35:28 +020034EXPORT_SYMBOL(end_pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
36/*
37 * end_pfn only includes RAM, while end_pfn_map includes all e820 entries.
38 * The direct mapping extends to end_pfn_map, so that we can directly access
39 * apertures, ACPI and other tables without having to play with fixmaps.
40 */
41unsigned long end_pfn_map;
42
43/*
44 * Last pfn which the user wants to use.
45 */
Jan Beulichcaff0712006-09-26 10:52:31 +020046static unsigned long __initdata end_user_pfn = MAXMEM>>PAGE_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48extern struct resource code_resource, data_resource;
49
50/* Check for some hardcoded bad areas that early boot is not allowed to touch */
51static inline int bad_addr(unsigned long *addrp, unsigned long size)
52{
53 unsigned long addr = *addrp, last = addr + size;
54
55 /* various gunk below that needed for SMP startup */
56 if (addr < 0x8000) {
Vivek Goyal73bb8912006-10-21 18:37:01 +020057 *addrp = PAGE_ALIGN(0x8000);
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 return 1;
59 }
60
61 /* direct mapping tables of the kernel */
62 if (last >= table_start<<PAGE_SHIFT && addr < table_end<<PAGE_SHIFT) {
Vivek Goyal73bb8912006-10-21 18:37:01 +020063 *addrp = PAGE_ALIGN(table_end << PAGE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 return 1;
65 }
66
67 /* initrd */
68#ifdef CONFIG_BLK_DEV_INITRD
69 if (LOADER_TYPE && INITRD_START && last >= INITRD_START &&
70 addr < INITRD_START+INITRD_SIZE) {
Vivek Goyal73bb8912006-10-21 18:37:01 +020071 *addrp = PAGE_ALIGN(INITRD_START + INITRD_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 return 1;
73 }
74#endif
Andi Kleendbf92722006-09-26 10:52:36 +020075 /* kernel code */
Vivek Goyal73bb8912006-10-21 18:37:01 +020076 if (last >= __pa_symbol(&_text) && addr < __pa_symbol(&_end)) {
77 *addrp = PAGE_ALIGN(__pa_symbol(&_end));
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 return 1;
79 }
Andi Kleenac71d122006-05-08 15:17:28 +020080
81 if (last >= ebda_addr && addr < ebda_addr + ebda_size) {
Vivek Goyal73bb8912006-10-21 18:37:01 +020082 *addrp = PAGE_ALIGN(ebda_addr + ebda_size);
Andi Kleenac71d122006-05-08 15:17:28 +020083 return 1;
84 }
85
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 /* XXX ramdisk image here? */
87 return 0;
88}
89
Arjan van de Ven95222362006-04-07 19:49:27 +020090/*
91 * This function checks if any part of the range <start,end> is mapped
92 * with type.
93 */
Arjan van de Veneee5a9f2006-04-07 19:49:24 +020094int __meminit
95e820_any_mapped(unsigned long start, unsigned long end, unsigned type)
Linus Torvalds1da177e2005-04-16 15:20:36 -070096{
97 int i;
98 for (i = 0; i < e820.nr_map; i++) {
99 struct e820entry *ei = &e820.map[i];
100 if (type && ei->type != type)
101 continue;
Eric W. Biederman48c8b112005-09-06 15:16:20 -0700102 if (ei->addr >= end || ei->addr + ei->size <= start)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 continue;
104 return 1;
105 }
106 return 0;
107}
108
Linus Torvalds79e453d2006-09-19 08:15:22 -0700109/*
110 * This function checks if the entire range <start,end> is mapped with type.
111 *
112 * Note: this function only works correct if the e820 table is sorted and
113 * not-overlapping, which is the case
114 */
115int __init e820_all_mapped(unsigned long start, unsigned long end, unsigned type)
116{
117 int i;
118 for (i = 0; i < e820.nr_map; i++) {
119 struct e820entry *ei = &e820.map[i];
120 if (type && ei->type != type)
121 continue;
122 /* is the region (part) in overlap with the current region ?*/
123 if (ei->addr >= end || ei->addr + ei->size <= start)
124 continue;
125
126 /* if the region is at the beginning of <start,end> we move
127 * start to the end of the region since it's ok until there
128 */
129 if (ei->addr <= start)
130 start = ei->addr + ei->size;
131 /* if start is now at or beyond end, we're done, full coverage */
132 if (start >= end)
133 return 1; /* we're done */
134 }
135 return 0;
136}
137
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138/*
139 * Find a free area in a specific range.
140 */
141unsigned long __init find_e820_area(unsigned long start, unsigned long end, unsigned size)
142{
143 int i;
144 for (i = 0; i < e820.nr_map; i++) {
145 struct e820entry *ei = &e820.map[i];
146 unsigned long addr = ei->addr, last;
147 if (ei->type != E820_RAM)
148 continue;
149 if (addr < start)
150 addr = start;
151 if (addr > ei->addr + ei->size)
152 continue;
Robert Hentosh7ca97c62006-05-30 22:48:00 +0200153 while (bad_addr(&addr, size) && addr+size <= ei->addr+ei->size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 ;
Vivek Goyal73bb8912006-10-21 18:37:01 +0200155 last = PAGE_ALIGN(addr) + size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 if (last > ei->addr + ei->size)
157 continue;
158 if (last > end)
159 continue;
160 return addr;
161 }
162 return -1UL;
163}
164
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165/*
166 * Find the highest page frame number we have available
167 */
168unsigned long __init e820_end_of_ram(void)
169{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 unsigned long end_pfn = 0;
Mel Gorman5cb248a2006-09-27 01:49:52 -0700171 end_pfn = find_max_pfn_with_active_regions();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 if (end_pfn > end_pfn_map)
174 end_pfn_map = end_pfn;
175 if (end_pfn_map > MAXMEM>>PAGE_SHIFT)
176 end_pfn_map = MAXMEM>>PAGE_SHIFT;
177 if (end_pfn > end_user_pfn)
178 end_pfn = end_user_pfn;
179 if (end_pfn > end_pfn_map)
180 end_pfn = end_pfn_map;
181
Mel Gorman5cb248a2006-09-27 01:49:52 -0700182 printk("end_pfn_map = %lu\n", end_pfn_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183 return end_pfn;
184}
185
Andi Kleen485761b2005-08-26 18:34:10 -0700186/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 * Mark e820 reserved areas as busy for the resource manager.
188 */
189void __init e820_reserve_resources(void)
190{
191 int i;
192 for (i = 0; i < e820.nr_map; i++) {
193 struct resource *res;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 res = alloc_bootmem_low(sizeof(struct resource));
195 switch (e820.map[i].type) {
196 case E820_RAM: res->name = "System RAM"; break;
197 case E820_ACPI: res->name = "ACPI Tables"; break;
198 case E820_NVS: res->name = "ACPI Non-volatile Storage"; break;
199 default: res->name = "reserved";
200 }
201 res->start = e820.map[i].addr;
202 res->end = res->start + e820.map[i].size - 1;
203 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
204 request_resource(&iomem_resource, res);
205 if (e820.map[i].type == E820_RAM) {
206 /*
207 * We don't know which RAM region contains kernel data,
208 * so we try it repeatedly and let the resource manager
209 * test it.
210 */
211 request_resource(res, &code_resource);
212 request_resource(res, &data_resource);
Eric W. Biederman5f5609d2005-06-25 14:58:04 -0700213#ifdef CONFIG_KEXEC
214 request_resource(res, &crashk_res);
215#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 }
217 }
218}
219
Rafael J. Wysockie8eff5a2006-09-25 23:32:46 -0700220/* Mark pages corresponding to given address range as nosave */
221static void __init
222e820_mark_nosave_range(unsigned long start, unsigned long end)
223{
224 unsigned long pfn, max_pfn;
225
226 if (start >= end)
227 return;
228
229 printk("Nosave address range: %016lx - %016lx\n", start, end);
230 max_pfn = end >> PAGE_SHIFT;
231 for (pfn = start >> PAGE_SHIFT; pfn < max_pfn; pfn++)
232 if (pfn_valid(pfn))
233 SetPageNosave(pfn_to_page(pfn));
234}
235
236/*
237 * Find the ranges of physical addresses that do not correspond to
238 * e820 RAM areas and mark the corresponding pages as nosave for software
239 * suspend and suspend to RAM.
240 *
241 * This function requires the e820 map to be sorted and without any
242 * overlapping entries and assumes the first e820 area to be RAM.
243 */
244void __init e820_mark_nosave_regions(void)
245{
246 int i;
247 unsigned long paddr;
248
249 paddr = round_down(e820.map[0].addr + e820.map[0].size, PAGE_SIZE);
250 for (i = 1; i < e820.nr_map; i++) {
251 struct e820entry *ei = &e820.map[i];
252
253 if (paddr < ei->addr)
254 e820_mark_nosave_range(paddr,
255 round_up(ei->addr, PAGE_SIZE));
256
257 paddr = round_down(ei->addr + ei->size, PAGE_SIZE);
258 if (ei->type != E820_RAM)
259 e820_mark_nosave_range(round_up(ei->addr, PAGE_SIZE),
260 paddr);
261
262 if (paddr >= (end_pfn << PAGE_SHIFT))
263 break;
264 }
265}
266
Mel Gorman5cb248a2006-09-27 01:49:52 -0700267/* Walk the e820 map and register active regions within a node */
268void __init
269e820_register_active_regions(int nid, unsigned long start_pfn,
270 unsigned long end_pfn)
271{
272 int i;
273 unsigned long ei_startpfn, ei_endpfn;
274 for (i = 0; i < e820.nr_map; i++) {
275 struct e820entry *ei = &e820.map[i];
276 ei_startpfn = round_up(ei->addr, PAGE_SIZE) >> PAGE_SHIFT;
277 ei_endpfn = round_down(ei->addr + ei->size, PAGE_SIZE)
278 >> PAGE_SHIFT;
279
280 /* Skip map entries smaller than a page */
Aaron Durbin14f448e2006-11-14 16:57:45 +0100281 if (ei_startpfn >= ei_endpfn)
Mel Gorman5cb248a2006-09-27 01:49:52 -0700282 continue;
283
284 /* Check if end_pfn_map should be updated */
285 if (ei->type != E820_RAM && ei_endpfn > end_pfn_map)
286 end_pfn_map = ei_endpfn;
287
288 /* Skip if map is outside the node */
289 if (ei->type != E820_RAM ||
290 ei_endpfn <= start_pfn ||
291 ei_startpfn >= end_pfn)
292 continue;
293
294 /* Check for overlaps */
295 if (ei_startpfn < start_pfn)
296 ei_startpfn = start_pfn;
297 if (ei_endpfn > end_pfn)
298 ei_endpfn = end_pfn;
299
300 /* Obey end_user_pfn to save on memmap */
301 if (ei_startpfn >= end_user_pfn)
302 continue;
303 if (ei_endpfn > end_user_pfn)
304 ei_endpfn = end_user_pfn;
305
306 add_active_range(nid, ei_startpfn, ei_endpfn);
307 }
308}
309
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310/*
311 * Add a memory region to the kernel e820 map.
312 */
313void __init add_memory_region(unsigned long start, unsigned long size, int type)
314{
315 int x = e820.nr_map;
316
317 if (x == E820MAX) {
318 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
319 return;
320 }
321
322 e820.map[x].addr = start;
323 e820.map[x].size = size;
324 e820.map[x].type = type;
325 e820.nr_map++;
326}
327
328void __init e820_print_map(char *who)
329{
330 int i;
331
332 for (i = 0; i < e820.nr_map; i++) {
333 printk(" %s: %016Lx - %016Lx ", who,
334 (unsigned long long) e820.map[i].addr,
335 (unsigned long long) (e820.map[i].addr + e820.map[i].size));
336 switch (e820.map[i].type) {
337 case E820_RAM: printk("(usable)\n");
338 break;
339 case E820_RESERVED:
340 printk("(reserved)\n");
341 break;
342 case E820_ACPI:
343 printk("(ACPI data)\n");
344 break;
345 case E820_NVS:
346 printk("(ACPI NVS)\n");
347 break;
348 default: printk("type %u\n", e820.map[i].type);
349 break;
350 }
351 }
352}
353
354/*
355 * Sanitize the BIOS e820 map.
356 *
357 * Some e820 responses include overlapping entries. The following
358 * replaces the original e820 map with a new one, removing overlaps.
359 *
360 */
361static int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map)
362{
363 struct change_member {
364 struct e820entry *pbios; /* pointer to original bios entry */
365 unsigned long long addr; /* address for this change point */
366 };
367 static struct change_member change_point_list[2*E820MAX] __initdata;
368 static struct change_member *change_point[2*E820MAX] __initdata;
369 static struct e820entry *overlap_list[E820MAX] __initdata;
370 static struct e820entry new_bios[E820MAX] __initdata;
371 struct change_member *change_tmp;
372 unsigned long current_type, last_type;
373 unsigned long long last_addr;
374 int chgidx, still_changing;
375 int overlap_entries;
376 int new_bios_entry;
Venkatesh Pallipadi8059b2a2005-05-01 08:58:52 -0700377 int old_nr, new_nr, chg_nr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 int i;
379
380 /*
381 Visually we're performing the following (1,2,3,4 = memory types)...
382
383 Sample memory map (w/overlaps):
384 ____22__________________
385 ______________________4_
386 ____1111________________
387 _44_____________________
388 11111111________________
389 ____________________33__
390 ___________44___________
391 __________33333_________
392 ______________22________
393 ___________________2222_
394 _________111111111______
395 _____________________11_
396 _________________4______
397
398 Sanitized equivalent (no overlap):
399 1_______________________
400 _44_____________________
401 ___1____________________
402 ____22__________________
403 ______11________________
404 _________1______________
405 __________3_____________
406 ___________44___________
407 _____________33_________
408 _______________2________
409 ________________1_______
410 _________________4______
411 ___________________2____
412 ____________________33__
413 ______________________4_
414 */
415
416 /* if there's only one memory region, don't bother */
417 if (*pnr_map < 2)
418 return -1;
419
420 old_nr = *pnr_map;
421
422 /* bail out if we find any unreasonable addresses in bios map */
423 for (i=0; i<old_nr; i++)
424 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
425 return -1;
426
427 /* create pointers for initial change-point information (for sorting) */
428 for (i=0; i < 2*old_nr; i++)
429 change_point[i] = &change_point_list[i];
430
Venkatesh Pallipadi8059b2a2005-05-01 08:58:52 -0700431 /* record all known change-points (starting and ending addresses),
432 omitting those that are for empty memory regions */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 chgidx = 0;
434 for (i=0; i < old_nr; i++) {
Venkatesh Pallipadi8059b2a2005-05-01 08:58:52 -0700435 if (biosmap[i].size != 0) {
436 change_point[chgidx]->addr = biosmap[i].addr;
437 change_point[chgidx++]->pbios = &biosmap[i];
438 change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size;
439 change_point[chgidx++]->pbios = &biosmap[i];
440 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 }
Venkatesh Pallipadi8059b2a2005-05-01 08:58:52 -0700442 chg_nr = chgidx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443
444 /* sort change-point list by memory addresses (low -> high) */
445 still_changing = 1;
446 while (still_changing) {
447 still_changing = 0;
Venkatesh Pallipadi8059b2a2005-05-01 08:58:52 -0700448 for (i=1; i < chg_nr; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 /* if <current_addr> > <last_addr>, swap */
450 /* or, if current=<start_addr> & last=<end_addr>, swap */
451 if ((change_point[i]->addr < change_point[i-1]->addr) ||
452 ((change_point[i]->addr == change_point[i-1]->addr) &&
453 (change_point[i]->addr == change_point[i]->pbios->addr) &&
454 (change_point[i-1]->addr != change_point[i-1]->pbios->addr))
455 )
456 {
457 change_tmp = change_point[i];
458 change_point[i] = change_point[i-1];
459 change_point[i-1] = change_tmp;
460 still_changing=1;
461 }
462 }
463 }
464
465 /* create a new bios memory map, removing overlaps */
466 overlap_entries=0; /* number of entries in the overlap table */
467 new_bios_entry=0; /* index for creating new bios map entries */
468 last_type = 0; /* start with undefined memory type */
469 last_addr = 0; /* start with 0 as last starting address */
470 /* loop through change-points, determining affect on the new bios map */
Venkatesh Pallipadi8059b2a2005-05-01 08:58:52 -0700471 for (chgidx=0; chgidx < chg_nr; chgidx++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 {
473 /* keep track of all overlapping bios entries */
474 if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr)
475 {
476 /* add map entry to overlap list (> 1 entry implies an overlap) */
477 overlap_list[overlap_entries++]=change_point[chgidx]->pbios;
478 }
479 else
480 {
481 /* remove entry from list (order independent, so swap with last) */
482 for (i=0; i<overlap_entries; i++)
483 {
484 if (overlap_list[i] == change_point[chgidx]->pbios)
485 overlap_list[i] = overlap_list[overlap_entries-1];
486 }
487 overlap_entries--;
488 }
489 /* if there are overlapping entries, decide which "type" to use */
490 /* (larger value takes precedence -- 1=usable, 2,3,4,4+=unusable) */
491 current_type = 0;
492 for (i=0; i<overlap_entries; i++)
493 if (overlap_list[i]->type > current_type)
494 current_type = overlap_list[i]->type;
495 /* continue building up new bios map based on this information */
496 if (current_type != last_type) {
497 if (last_type != 0) {
498 new_bios[new_bios_entry].size =
499 change_point[chgidx]->addr - last_addr;
500 /* move forward only if the new size was non-zero */
501 if (new_bios[new_bios_entry].size != 0)
502 if (++new_bios_entry >= E820MAX)
503 break; /* no more space left for new bios entries */
504 }
505 if (current_type != 0) {
506 new_bios[new_bios_entry].addr = change_point[chgidx]->addr;
507 new_bios[new_bios_entry].type = current_type;
508 last_addr=change_point[chgidx]->addr;
509 }
510 last_type = current_type;
511 }
512 }
513 new_nr = new_bios_entry; /* retain count for new bios entries */
514
515 /* copy new bios mapping into original location */
516 memcpy(biosmap, new_bios, new_nr*sizeof(struct e820entry));
517 *pnr_map = new_nr;
518
519 return 0;
520}
521
522/*
523 * Copy the BIOS e820 map into a safe place.
524 *
525 * Sanity-check it while we're at it..
526 *
527 * If we're lucky and live on a modern system, the setup code
528 * will have given us a memory map that we can use to properly
529 * set up memory. If we aren't, we'll fake a memory map.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 */
531static int __init copy_e820_map(struct e820entry * biosmap, int nr_map)
532{
533 /* Only one memory region (or negative)? Ignore it */
534 if (nr_map < 2)
535 return -1;
536
537 do {
538 unsigned long start = biosmap->addr;
539 unsigned long size = biosmap->size;
540 unsigned long end = start + size;
541 unsigned long type = biosmap->type;
542
543 /* Overflow in 64 bits? Ignore the memory map. */
544 if (start > end)
545 return -1;
546
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 add_memory_region(start, size, type);
548 } while (biosmap++,--nr_map);
549 return 0;
550}
551
Andi Kleen8380aab2006-09-26 10:52:37 +0200552void early_panic(char *msg)
553{
554 early_printk(msg);
555 panic(msg);
556}
557
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558void __init setup_memory_region(void)
559{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 /*
561 * Try to copy the BIOS-supplied E820-map.
562 *
563 * Otherwise fake a memory map; one section from 0k->640k,
564 * the next section from 1mb->appropriate_mem_k
565 */
566 sanitize_e820_map(E820_MAP, &E820_MAP_NR);
Andi Kleen8380aab2006-09-26 10:52:37 +0200567 if (copy_e820_map(E820_MAP, E820_MAP_NR) < 0)
568 early_panic("Cannot find a valid memory map");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 printk(KERN_INFO "BIOS-provided physical RAM map:\n");
Andi Kleen8380aab2006-09-26 10:52:37 +0200570 e820_print_map("BIOS-e820");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571}
572
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200573static int __init parse_memopt(char *p)
akpm@osdl.org69cda7b2006-01-09 20:51:46 -0800574{
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200575 if (!p)
576 return -EINVAL;
577 end_user_pfn = memparse(p, &p);
578 end_user_pfn >>= PAGE_SHIFT;
579 return 0;
580}
581early_param("mem", parse_memopt);
582
583static int userdef __initdata;
584
585static int __init parse_memmap_opt(char *p)
586{
587 char *oldp;
akpm@osdl.org69cda7b2006-01-09 20:51:46 -0800588 unsigned long long start_at, mem_size;
589
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200590 if (!strcmp(p, "exactmap")) {
591#ifdef CONFIG_CRASH_DUMP
592 /* If we are doing a crash dump, we
593 * still need to know the real mem
594 * size before original memory map is
595 * reset.
596 */
Magnus Damm15803a42006-11-14 16:57:46 +0100597 e820_register_active_regions(0, 0, -1UL);
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200598 saved_max_pfn = e820_end_of_ram();
Magnus Damm15803a42006-11-14 16:57:46 +0100599 remove_all_active_ranges();
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200600#endif
601 end_pfn_map = 0;
602 e820.nr_map = 0;
603 userdef = 1;
604 return 0;
605 }
606
607 oldp = p;
608 mem_size = memparse(p, &p);
609 if (p == oldp)
610 return -EINVAL;
akpm@osdl.org69cda7b2006-01-09 20:51:46 -0800611 if (*p == '@') {
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200612 start_at = memparse(p+1, &p);
akpm@osdl.org69cda7b2006-01-09 20:51:46 -0800613 add_memory_region(start_at, mem_size, E820_RAM);
614 } else if (*p == '#') {
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200615 start_at = memparse(p+1, &p);
akpm@osdl.org69cda7b2006-01-09 20:51:46 -0800616 add_memory_region(start_at, mem_size, E820_ACPI);
617 } else if (*p == '$') {
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200618 start_at = memparse(p+1, &p);
akpm@osdl.org69cda7b2006-01-09 20:51:46 -0800619 add_memory_region(start_at, mem_size, E820_RESERVED);
620 } else {
621 end_user_pfn = (mem_size >> PAGE_SHIFT);
622 }
Andi Kleen2c8c0e62006-09-26 10:52:32 +0200623 return *p == '\0' ? 0 : -EINVAL;
624}
625early_param("memmap", parse_memmap_opt);
626
627void finish_e820_parsing(void)
628{
629 if (userdef) {
630 printk(KERN_INFO "user-defined physical RAM map:\n");
631 e820_print_map("user");
632 }
akpm@osdl.org69cda7b2006-01-09 20:51:46 -0800633}
634
Andi Kleena1e97782005-04-16 15:25:12 -0700635unsigned long pci_mem_start = 0xaeedbabe;
Andi Kleen2ee60e172006-06-26 13:59:44 +0200636EXPORT_SYMBOL(pci_mem_start);
Andi Kleena1e97782005-04-16 15:25:12 -0700637
638/*
639 * Search for the biggest gap in the low 32 bits of the e820
640 * memory space. We pass this space to PCI to assign MMIO resources
641 * for hotplug or unconfigured devices in.
642 * Hopefully the BIOS let enough space left.
643 */
644__init void e820_setup_gap(void)
645{
Daniel Ritzf0eca962005-09-09 00:57:14 +0200646 unsigned long gapstart, gapsize, round;
Andi Kleena1e97782005-04-16 15:25:12 -0700647 unsigned long last;
648 int i;
649 int found = 0;
650
651 last = 0x100000000ull;
652 gapstart = 0x10000000;
653 gapsize = 0x400000;
654 i = e820.nr_map;
655 while (--i >= 0) {
656 unsigned long long start = e820.map[i].addr;
657 unsigned long long end = start + e820.map[i].size;
658
659 /*
660 * Since "last" is at most 4GB, we know we'll
661 * fit in 32 bits if this condition is true
662 */
663 if (last > end) {
664 unsigned long gap = last - end;
665
666 if (gap > gapsize) {
667 gapsize = gap;
668 gapstart = end;
669 found = 1;
670 }
671 }
672 if (start < last)
673 last = start;
674 }
675
676 if (!found) {
677 gapstart = (end_pfn << PAGE_SHIFT) + 1024*1024;
678 printk(KERN_ERR "PCI: Warning: Cannot find a gap in the 32bit address range\n"
679 KERN_ERR "PCI: Unassigned devices with 32bit resource registers may break!\n");
680 }
681
682 /*
Daniel Ritzf0eca962005-09-09 00:57:14 +0200683 * See how much we want to round up: start off with
684 * rounding to the next 1MB area.
Andi Kleena1e97782005-04-16 15:25:12 -0700685 */
Daniel Ritzf0eca962005-09-09 00:57:14 +0200686 round = 0x100000;
687 while ((gapsize >> 4) > round)
688 round += round;
689 /* Fun with two's complement */
690 pci_mem_start = (gapstart + round) & -round;
Andi Kleena1e97782005-04-16 15:25:12 -0700691
692 printk(KERN_INFO "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
693 pci_mem_start, gapstart, gapsize);
694}