Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Handle the memory map. | |
3 | * The functions here do the job until bootmem takes over. | |
8059b2a2 VP |
4 | * |
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 | * | |
1da177e4 | 10 | */ |
1da177e4 LT |
11 | #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> | |
5f5609df | 17 | #include <linux/kexec.h> |
b9491ac8 AM |
18 | #include <linux/module.h> |
19 | ||
1a91023a | 20 | #include <asm/pgtable.h> |
1da177e4 LT |
21 | #include <asm/page.h> |
22 | #include <asm/e820.h> | |
23 | #include <asm/proto.h> | |
24 | #include <asm/bootsetup.h> | |
2bc0414e | 25 | #include <asm/sections.h> |
1da177e4 | 26 | |
3bd4d18c AK |
27 | struct e820map e820 __initdata; |
28 | ||
1da177e4 LT |
29 | /* |
30 | * PFN of last memory page. | |
31 | */ | |
32 | unsigned long end_pfn; | |
f3591fff | 33 | EXPORT_SYMBOL(end_pfn); |
1da177e4 LT |
34 | |
35 | /* | |
36 | * end_pfn only includes RAM, while end_pfn_map includes all e820 entries. | |
37 | * The direct mapping extends to end_pfn_map, so that we can directly access | |
38 | * apertures, ACPI and other tables without having to play with fixmaps. | |
39 | */ | |
40 | unsigned long end_pfn_map; | |
41 | ||
42 | /* | |
43 | * Last pfn which the user wants to use. | |
44 | */ | |
caff0710 | 45 | static unsigned long __initdata end_user_pfn = MAXMEM>>PAGE_SHIFT; |
1da177e4 LT |
46 | |
47 | extern struct resource code_resource, data_resource; | |
48 | ||
49 | /* Check for some hardcoded bad areas that early boot is not allowed to touch */ | |
50 | static inline int bad_addr(unsigned long *addrp, unsigned long size) | |
51 | { | |
52 | unsigned long addr = *addrp, last = addr + size; | |
53 | ||
54 | /* various gunk below that needed for SMP startup */ | |
55 | if (addr < 0x8000) { | |
56 | *addrp = 0x8000; | |
57 | return 1; | |
58 | } | |
59 | ||
60 | /* direct mapping tables of the kernel */ | |
61 | if (last >= table_start<<PAGE_SHIFT && addr < table_end<<PAGE_SHIFT) { | |
62 | *addrp = table_end << PAGE_SHIFT; | |
63 | return 1; | |
64 | } | |
65 | ||
66 | /* initrd */ | |
67 | #ifdef CONFIG_BLK_DEV_INITRD | |
68 | if (LOADER_TYPE && INITRD_START && last >= INITRD_START && | |
69 | addr < INITRD_START+INITRD_SIZE) { | |
70 | *addrp = INITRD_START + INITRD_SIZE; | |
71 | return 1; | |
72 | } | |
73 | #endif | |
dbf9272e | 74 | /* kernel code */ |
ceee8822 | 75 | if (last >= __pa_symbol(&_text) && last < __pa_symbol(&_end)) { |
1da177e4 LT |
76 | *addrp = __pa_symbol(&_end); |
77 | return 1; | |
78 | } | |
ac71d12c AK |
79 | |
80 | if (last >= ebda_addr && addr < ebda_addr + ebda_size) { | |
81 | *addrp = ebda_addr + ebda_size; | |
82 | return 1; | |
83 | } | |
84 | ||
1da177e4 LT |
85 | /* XXX ramdisk image here? */ |
86 | return 0; | |
87 | } | |
88 | ||
95222368 AV |
89 | /* |
90 | * This function checks if any part of the range <start,end> is mapped | |
91 | * with type. | |
92 | */ | |
eee5a9fa AV |
93 | int __meminit |
94 | e820_any_mapped(unsigned long start, unsigned long end, unsigned type) | |
1da177e4 LT |
95 | { |
96 | int i; | |
97 | for (i = 0; i < e820.nr_map; i++) { | |
98 | struct e820entry *ei = &e820.map[i]; | |
99 | if (type && ei->type != type) | |
100 | continue; | |
48c8b113 | 101 | if (ei->addr >= end || ei->addr + ei->size <= start) |
1da177e4 LT |
102 | continue; |
103 | return 1; | |
104 | } | |
105 | return 0; | |
106 | } | |
107 | ||
79e453d4 LT |
108 | /* |
109 | * This function checks if the entire range <start,end> is mapped with type. | |
110 | * | |
111 | * Note: this function only works correct if the e820 table is sorted and | |
112 | * not-overlapping, which is the case | |
113 | */ | |
114 | int __init e820_all_mapped(unsigned long start, unsigned long end, unsigned type) | |
115 | { | |
116 | int i; | |
117 | for (i = 0; i < e820.nr_map; i++) { | |
118 | struct e820entry *ei = &e820.map[i]; | |
119 | if (type && ei->type != type) | |
120 | continue; | |
121 | /* is the region (part) in overlap with the current region ?*/ | |
122 | if (ei->addr >= end || ei->addr + ei->size <= start) | |
123 | continue; | |
124 | ||
125 | /* if the region is at the beginning of <start,end> we move | |
126 | * start to the end of the region since it's ok until there | |
127 | */ | |
128 | if (ei->addr <= start) | |
129 | start = ei->addr + ei->size; | |
130 | /* if start is now at or beyond end, we're done, full coverage */ | |
131 | if (start >= end) | |
132 | return 1; /* we're done */ | |
133 | } | |
134 | return 0; | |
135 | } | |
136 | ||
1da177e4 LT |
137 | /* |
138 | * Find a free area in a specific range. | |
139 | */ | |
140 | unsigned long __init find_e820_area(unsigned long start, unsigned long end, unsigned size) | |
141 | { | |
142 | int i; | |
143 | for (i = 0; i < e820.nr_map; i++) { | |
144 | struct e820entry *ei = &e820.map[i]; | |
145 | unsigned long addr = ei->addr, last; | |
146 | if (ei->type != E820_RAM) | |
147 | continue; | |
148 | if (addr < start) | |
149 | addr = start; | |
150 | if (addr > ei->addr + ei->size) | |
151 | continue; | |
7ca97c61 | 152 | while (bad_addr(&addr, size) && addr+size <= ei->addr+ei->size) |
1da177e4 LT |
153 | ; |
154 | last = addr + size; | |
155 | if (last > ei->addr + ei->size) | |
156 | continue; | |
157 | if (last > end) | |
158 | continue; | |
159 | return addr; | |
160 | } | |
161 | return -1UL; | |
162 | } | |
163 | ||
164 | /* | |
165 | * Free bootmem based on the e820 table for a node. | |
166 | */ | |
167 | void __init e820_bootmem_free(pg_data_t *pgdat, unsigned long start,unsigned long end) | |
168 | { | |
169 | int i; | |
170 | for (i = 0; i < e820.nr_map; i++) { | |
171 | struct e820entry *ei = &e820.map[i]; | |
172 | unsigned long last, addr; | |
173 | ||
174 | if (ei->type != E820_RAM || | |
175 | ei->addr+ei->size <= start || | |
7c7a3897 | 176 | ei->addr >= end) |
1da177e4 LT |
177 | continue; |
178 | ||
179 | addr = round_up(ei->addr, PAGE_SIZE); | |
180 | if (addr < start) | |
181 | addr = start; | |
182 | ||
183 | last = round_down(ei->addr + ei->size, PAGE_SIZE); | |
184 | if (last >= end) | |
185 | last = end; | |
186 | ||
187 | if (last > addr && last-addr >= PAGE_SIZE) | |
188 | free_bootmem_node(pgdat, addr, last-addr); | |
189 | } | |
190 | } | |
191 | ||
192 | /* | |
193 | * Find the highest page frame number we have available | |
194 | */ | |
195 | unsigned long __init e820_end_of_ram(void) | |
196 | { | |
197 | int i; | |
198 | unsigned long end_pfn = 0; | |
199 | ||
200 | for (i = 0; i < e820.nr_map; i++) { | |
201 | struct e820entry *ei = &e820.map[i]; | |
202 | unsigned long start, end; | |
203 | ||
204 | start = round_up(ei->addr, PAGE_SIZE); | |
205 | end = round_down(ei->addr + ei->size, PAGE_SIZE); | |
206 | if (start >= end) | |
207 | continue; | |
208 | if (ei->type == E820_RAM) { | |
209 | if (end > end_pfn<<PAGE_SHIFT) | |
210 | end_pfn = end>>PAGE_SHIFT; | |
211 | } else { | |
212 | if (end > end_pfn_map<<PAGE_SHIFT) | |
213 | end_pfn_map = end>>PAGE_SHIFT; | |
214 | } | |
215 | } | |
216 | ||
217 | if (end_pfn > end_pfn_map) | |
218 | end_pfn_map = end_pfn; | |
219 | if (end_pfn_map > MAXMEM>>PAGE_SHIFT) | |
220 | end_pfn_map = MAXMEM>>PAGE_SHIFT; | |
221 | if (end_pfn > end_user_pfn) | |
222 | end_pfn = end_user_pfn; | |
223 | if (end_pfn > end_pfn_map) | |
224 | end_pfn = end_pfn_map; | |
225 | ||
226 | return end_pfn; | |
227 | } | |
228 | ||
229 | /* | |
485761bd AK |
230 | * Compute how much memory is missing in a range. |
231 | * Unlike the other functions in this file the arguments are in page numbers. | |
232 | */ | |
233 | unsigned long __init | |
234 | e820_hole_size(unsigned long start_pfn, unsigned long end_pfn) | |
235 | { | |
236 | unsigned long ram = 0; | |
237 | unsigned long start = start_pfn << PAGE_SHIFT; | |
238 | unsigned long end = end_pfn << PAGE_SHIFT; | |
239 | int i; | |
240 | for (i = 0; i < e820.nr_map; i++) { | |
241 | struct e820entry *ei = &e820.map[i]; | |
242 | unsigned long last, addr; | |
243 | ||
244 | if (ei->type != E820_RAM || | |
245 | ei->addr+ei->size <= start || | |
246 | ei->addr >= end) | |
247 | continue; | |
248 | ||
249 | addr = round_up(ei->addr, PAGE_SIZE); | |
250 | if (addr < start) | |
251 | addr = start; | |
252 | ||
253 | last = round_down(ei->addr + ei->size, PAGE_SIZE); | |
254 | if (last >= end) | |
255 | last = end; | |
256 | ||
257 | if (last > addr) | |
258 | ram += last - addr; | |
259 | } | |
260 | return ((end - start) - ram) >> PAGE_SHIFT; | |
261 | } | |
262 | ||
263 | /* | |
1da177e4 LT |
264 | * Mark e820 reserved areas as busy for the resource manager. |
265 | */ | |
266 | void __init e820_reserve_resources(void) | |
267 | { | |
268 | int i; | |
269 | for (i = 0; i < e820.nr_map; i++) { | |
270 | struct resource *res; | |
1da177e4 LT |
271 | res = alloc_bootmem_low(sizeof(struct resource)); |
272 | switch (e820.map[i].type) { | |
273 | case E820_RAM: res->name = "System RAM"; break; | |
274 | case E820_ACPI: res->name = "ACPI Tables"; break; | |
275 | case E820_NVS: res->name = "ACPI Non-volatile Storage"; break; | |
276 | default: res->name = "reserved"; | |
277 | } | |
278 | res->start = e820.map[i].addr; | |
279 | res->end = res->start + e820.map[i].size - 1; | |
280 | res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; | |
281 | request_resource(&iomem_resource, res); | |
282 | if (e820.map[i].type == E820_RAM) { | |
283 | /* | |
284 | * We don't know which RAM region contains kernel data, | |
285 | * so we try it repeatedly and let the resource manager | |
286 | * test it. | |
287 | */ | |
288 | request_resource(res, &code_resource); | |
289 | request_resource(res, &data_resource); | |
5f5609df EB |
290 | #ifdef CONFIG_KEXEC |
291 | request_resource(res, &crashk_res); | |
292 | #endif | |
1da177e4 LT |
293 | } |
294 | } | |
295 | } | |
296 | ||
297 | /* | |
298 | * Add a memory region to the kernel e820 map. | |
299 | */ | |
300 | void __init add_memory_region(unsigned long start, unsigned long size, int type) | |
301 | { | |
302 | int x = e820.nr_map; | |
303 | ||
304 | if (x == E820MAX) { | |
305 | printk(KERN_ERR "Ooops! Too many entries in the memory map!\n"); | |
306 | return; | |
307 | } | |
308 | ||
309 | e820.map[x].addr = start; | |
310 | e820.map[x].size = size; | |
311 | e820.map[x].type = type; | |
312 | e820.nr_map++; | |
313 | } | |
314 | ||
315 | void __init e820_print_map(char *who) | |
316 | { | |
317 | int i; | |
318 | ||
319 | for (i = 0; i < e820.nr_map; i++) { | |
320 | printk(" %s: %016Lx - %016Lx ", who, | |
321 | (unsigned long long) e820.map[i].addr, | |
322 | (unsigned long long) (e820.map[i].addr + e820.map[i].size)); | |
323 | switch (e820.map[i].type) { | |
324 | case E820_RAM: printk("(usable)\n"); | |
325 | break; | |
326 | case E820_RESERVED: | |
327 | printk("(reserved)\n"); | |
328 | break; | |
329 | case E820_ACPI: | |
330 | printk("(ACPI data)\n"); | |
331 | break; | |
332 | case E820_NVS: | |
333 | printk("(ACPI NVS)\n"); | |
334 | break; | |
335 | default: printk("type %u\n", e820.map[i].type); | |
336 | break; | |
337 | } | |
338 | } | |
339 | } | |
340 | ||
341 | /* | |
342 | * Sanitize the BIOS e820 map. | |
343 | * | |
344 | * Some e820 responses include overlapping entries. The following | |
345 | * replaces the original e820 map with a new one, removing overlaps. | |
346 | * | |
347 | */ | |
348 | static int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map) | |
349 | { | |
350 | struct change_member { | |
351 | struct e820entry *pbios; /* pointer to original bios entry */ | |
352 | unsigned long long addr; /* address for this change point */ | |
353 | }; | |
354 | static struct change_member change_point_list[2*E820MAX] __initdata; | |
355 | static struct change_member *change_point[2*E820MAX] __initdata; | |
356 | static struct e820entry *overlap_list[E820MAX] __initdata; | |
357 | static struct e820entry new_bios[E820MAX] __initdata; | |
358 | struct change_member *change_tmp; | |
359 | unsigned long current_type, last_type; | |
360 | unsigned long long last_addr; | |
361 | int chgidx, still_changing; | |
362 | int overlap_entries; | |
363 | int new_bios_entry; | |
8059b2a2 | 364 | int old_nr, new_nr, chg_nr; |
1da177e4 LT |
365 | int i; |
366 | ||
367 | /* | |
368 | Visually we're performing the following (1,2,3,4 = memory types)... | |
369 | ||
370 | Sample memory map (w/overlaps): | |
371 | ____22__________________ | |
372 | ______________________4_ | |
373 | ____1111________________ | |
374 | _44_____________________ | |
375 | 11111111________________ | |
376 | ____________________33__ | |
377 | ___________44___________ | |
378 | __________33333_________ | |
379 | ______________22________ | |
380 | ___________________2222_ | |
381 | _________111111111______ | |
382 | _____________________11_ | |
383 | _________________4______ | |
384 | ||
385 | Sanitized equivalent (no overlap): | |
386 | 1_______________________ | |
387 | _44_____________________ | |
388 | ___1____________________ | |
389 | ____22__________________ | |
390 | ______11________________ | |
391 | _________1______________ | |
392 | __________3_____________ | |
393 | ___________44___________ | |
394 | _____________33_________ | |
395 | _______________2________ | |
396 | ________________1_______ | |
397 | _________________4______ | |
398 | ___________________2____ | |
399 | ____________________33__ | |
400 | ______________________4_ | |
401 | */ | |
402 | ||
403 | /* if there's only one memory region, don't bother */ | |
404 | if (*pnr_map < 2) | |
405 | return -1; | |
406 | ||
407 | old_nr = *pnr_map; | |
408 | ||
409 | /* bail out if we find any unreasonable addresses in bios map */ | |
410 | for (i=0; i<old_nr; i++) | |
411 | if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr) | |
412 | return -1; | |
413 | ||
414 | /* create pointers for initial change-point information (for sorting) */ | |
415 | for (i=0; i < 2*old_nr; i++) | |
416 | change_point[i] = &change_point_list[i]; | |
417 | ||
8059b2a2 VP |
418 | /* record all known change-points (starting and ending addresses), |
419 | omitting those that are for empty memory regions */ | |
1da177e4 LT |
420 | chgidx = 0; |
421 | for (i=0; i < old_nr; i++) { | |
8059b2a2 VP |
422 | if (biosmap[i].size != 0) { |
423 | change_point[chgidx]->addr = biosmap[i].addr; | |
424 | change_point[chgidx++]->pbios = &biosmap[i]; | |
425 | change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size; | |
426 | change_point[chgidx++]->pbios = &biosmap[i]; | |
427 | } | |
1da177e4 | 428 | } |
8059b2a2 | 429 | chg_nr = chgidx; |
1da177e4 LT |
430 | |
431 | /* sort change-point list by memory addresses (low -> high) */ | |
432 | still_changing = 1; | |
433 | while (still_changing) { | |
434 | still_changing = 0; | |
8059b2a2 | 435 | for (i=1; i < chg_nr; i++) { |
1da177e4 LT |
436 | /* if <current_addr> > <last_addr>, swap */ |
437 | /* or, if current=<start_addr> & last=<end_addr>, swap */ | |
438 | if ((change_point[i]->addr < change_point[i-1]->addr) || | |
439 | ((change_point[i]->addr == change_point[i-1]->addr) && | |
440 | (change_point[i]->addr == change_point[i]->pbios->addr) && | |
441 | (change_point[i-1]->addr != change_point[i-1]->pbios->addr)) | |
442 | ) | |
443 | { | |
444 | change_tmp = change_point[i]; | |
445 | change_point[i] = change_point[i-1]; | |
446 | change_point[i-1] = change_tmp; | |
447 | still_changing=1; | |
448 | } | |
449 | } | |
450 | } | |
451 | ||
452 | /* create a new bios memory map, removing overlaps */ | |
453 | overlap_entries=0; /* number of entries in the overlap table */ | |
454 | new_bios_entry=0; /* index for creating new bios map entries */ | |
455 | last_type = 0; /* start with undefined memory type */ | |
456 | last_addr = 0; /* start with 0 as last starting address */ | |
457 | /* loop through change-points, determining affect on the new bios map */ | |
8059b2a2 | 458 | for (chgidx=0; chgidx < chg_nr; chgidx++) |
1da177e4 LT |
459 | { |
460 | /* keep track of all overlapping bios entries */ | |
461 | if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr) | |
462 | { | |
463 | /* add map entry to overlap list (> 1 entry implies an overlap) */ | |
464 | overlap_list[overlap_entries++]=change_point[chgidx]->pbios; | |
465 | } | |
466 | else | |
467 | { | |
468 | /* remove entry from list (order independent, so swap with last) */ | |
469 | for (i=0; i<overlap_entries; i++) | |
470 | { | |
471 | if (overlap_list[i] == change_point[chgidx]->pbios) | |
472 | overlap_list[i] = overlap_list[overlap_entries-1]; | |
473 | } | |
474 | overlap_entries--; | |
475 | } | |
476 | /* if there are overlapping entries, decide which "type" to use */ | |
477 | /* (larger value takes precedence -- 1=usable, 2,3,4,4+=unusable) */ | |
478 | current_type = 0; | |
479 | for (i=0; i<overlap_entries; i++) | |
480 | if (overlap_list[i]->type > current_type) | |
481 | current_type = overlap_list[i]->type; | |
482 | /* continue building up new bios map based on this information */ | |
483 | if (current_type != last_type) { | |
484 | if (last_type != 0) { | |
485 | new_bios[new_bios_entry].size = | |
486 | change_point[chgidx]->addr - last_addr; | |
487 | /* move forward only if the new size was non-zero */ | |
488 | if (new_bios[new_bios_entry].size != 0) | |
489 | if (++new_bios_entry >= E820MAX) | |
490 | break; /* no more space left for new bios entries */ | |
491 | } | |
492 | if (current_type != 0) { | |
493 | new_bios[new_bios_entry].addr = change_point[chgidx]->addr; | |
494 | new_bios[new_bios_entry].type = current_type; | |
495 | last_addr=change_point[chgidx]->addr; | |
496 | } | |
497 | last_type = current_type; | |
498 | } | |
499 | } | |
500 | new_nr = new_bios_entry; /* retain count for new bios entries */ | |
501 | ||
502 | /* copy new bios mapping into original location */ | |
503 | memcpy(biosmap, new_bios, new_nr*sizeof(struct e820entry)); | |
504 | *pnr_map = new_nr; | |
505 | ||
506 | return 0; | |
507 | } | |
508 | ||
509 | /* | |
510 | * Copy the BIOS e820 map into a safe place. | |
511 | * | |
512 | * Sanity-check it while we're at it.. | |
513 | * | |
514 | * If we're lucky and live on a modern system, the setup code | |
515 | * will have given us a memory map that we can use to properly | |
516 | * set up memory. If we aren't, we'll fake a memory map. | |
1da177e4 LT |
517 | */ |
518 | static int __init copy_e820_map(struct e820entry * biosmap, int nr_map) | |
519 | { | |
520 | /* Only one memory region (or negative)? Ignore it */ | |
521 | if (nr_map < 2) | |
522 | return -1; | |
523 | ||
524 | do { | |
525 | unsigned long start = biosmap->addr; | |
526 | unsigned long size = biosmap->size; | |
527 | unsigned long end = start + size; | |
528 | unsigned long type = biosmap->type; | |
529 | ||
530 | /* Overflow in 64 bits? Ignore the memory map. */ | |
531 | if (start > end) | |
532 | return -1; | |
533 | ||
1da177e4 LT |
534 | add_memory_region(start, size, type); |
535 | } while (biosmap++,--nr_map); | |
536 | return 0; | |
537 | } | |
538 | ||
539 | void __init setup_memory_region(void) | |
540 | { | |
541 | char *who = "BIOS-e820"; | |
542 | ||
543 | /* | |
544 | * Try to copy the BIOS-supplied E820-map. | |
545 | * | |
546 | * Otherwise fake a memory map; one section from 0k->640k, | |
547 | * the next section from 1mb->appropriate_mem_k | |
548 | */ | |
549 | sanitize_e820_map(E820_MAP, &E820_MAP_NR); | |
550 | if (copy_e820_map(E820_MAP, E820_MAP_NR) < 0) { | |
551 | unsigned long mem_size; | |
552 | ||
553 | /* compare results from other methods and take the greater */ | |
554 | if (ALT_MEM_K < EXT_MEM_K) { | |
555 | mem_size = EXT_MEM_K; | |
556 | who = "BIOS-88"; | |
557 | } else { | |
558 | mem_size = ALT_MEM_K; | |
559 | who = "BIOS-e801"; | |
560 | } | |
561 | ||
562 | e820.nr_map = 0; | |
563 | add_memory_region(0, LOWMEMSIZE(), E820_RAM); | |
564 | add_memory_region(HIGH_MEMORY, mem_size << 10, E820_RAM); | |
565 | } | |
566 | printk(KERN_INFO "BIOS-provided physical RAM map:\n"); | |
567 | e820_print_map(who); | |
568 | } | |
569 | ||
2c8c0e6b AK |
570 | static int __init parse_memopt(char *p) |
571 | { | |
572 | if (!p) | |
573 | return -EINVAL; | |
574 | end_user_pfn = memparse(p, &p); | |
1da177e4 | 575 | end_user_pfn >>= PAGE_SHIFT; |
2c8c0e6b | 576 | return 0; |
1da177e4 | 577 | } |
2c8c0e6b AK |
578 | early_param("mem", parse_memopt); |
579 | ||
580 | static int userdef __initdata; | |
1da177e4 | 581 | |
2c8c0e6b | 582 | static int __init parse_memmap_opt(char *p) |
69cda7b1 | 583 | { |
2c8c0e6b | 584 | char *oldp; |
69cda7b1 | 585 | unsigned long long start_at, mem_size; |
586 | ||
2c8c0e6b AK |
587 | if (!strcmp(p, "exactmap")) { |
588 | #ifdef CONFIG_CRASH_DUMP | |
589 | /* If we are doing a crash dump, we | |
590 | * still need to know the real mem | |
591 | * size before original memory map is | |
592 | * reset. | |
593 | */ | |
594 | saved_max_pfn = e820_end_of_ram(); | |
595 | #endif | |
596 | end_pfn_map = 0; | |
597 | e820.nr_map = 0; | |
598 | userdef = 1; | |
599 | return 0; | |
600 | } | |
601 | ||
602 | oldp = p; | |
603 | mem_size = memparse(p, &p); | |
604 | if (p == oldp) | |
605 | return -EINVAL; | |
69cda7b1 | 606 | if (*p == '@') { |
2c8c0e6b | 607 | start_at = memparse(p+1, &p); |
69cda7b1 | 608 | add_memory_region(start_at, mem_size, E820_RAM); |
609 | } else if (*p == '#') { | |
2c8c0e6b | 610 | start_at = memparse(p+1, &p); |
69cda7b1 | 611 | add_memory_region(start_at, mem_size, E820_ACPI); |
612 | } else if (*p == '$') { | |
2c8c0e6b | 613 | start_at = memparse(p+1, &p); |
69cda7b1 | 614 | add_memory_region(start_at, mem_size, E820_RESERVED); |
615 | } else { | |
616 | end_user_pfn = (mem_size >> PAGE_SHIFT); | |
617 | } | |
2c8c0e6b AK |
618 | return *p == '\0' ? 0 : -EINVAL; |
619 | } | |
620 | early_param("memmap", parse_memmap_opt); | |
621 | ||
622 | void finish_e820_parsing(void) | |
623 | { | |
624 | if (userdef) { | |
625 | printk(KERN_INFO "user-defined physical RAM map:\n"); | |
626 | e820_print_map("user"); | |
627 | } | |
69cda7b1 | 628 | } |
629 | ||
a1e97782 | 630 | unsigned long pci_mem_start = 0xaeedbabe; |
2ee60e17 | 631 | EXPORT_SYMBOL(pci_mem_start); |
a1e97782 AK |
632 | |
633 | /* | |
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. | |
638 | */ | |
639 | __init void e820_setup_gap(void) | |
640 | { | |
f0eca962 | 641 | unsigned long gapstart, gapsize, round; |
a1e97782 AK |
642 | unsigned long last; |
643 | int i; | |
644 | int found = 0; | |
645 | ||
646 | last = 0x100000000ull; | |
647 | gapstart = 0x10000000; | |
648 | gapsize = 0x400000; | |
649 | i = e820.nr_map; | |
650 | while (--i >= 0) { | |
651 | unsigned long long start = e820.map[i].addr; | |
652 | unsigned long long end = start + e820.map[i].size; | |
653 | ||
654 | /* | |
655 | * Since "last" is at most 4GB, we know we'll | |
656 | * fit in 32 bits if this condition is true | |
657 | */ | |
658 | if (last > end) { | |
659 | unsigned long gap = last - end; | |
660 | ||
661 | if (gap > gapsize) { | |
662 | gapsize = gap; | |
663 | gapstart = end; | |
664 | found = 1; | |
665 | } | |
666 | } | |
667 | if (start < last) | |
668 | last = start; | |
669 | } | |
670 | ||
671 | if (!found) { | |
672 | gapstart = (end_pfn << PAGE_SHIFT) + 1024*1024; | |
673 | printk(KERN_ERR "PCI: Warning: Cannot find a gap in the 32bit address range\n" | |
674 | KERN_ERR "PCI: Unassigned devices with 32bit resource registers may break!\n"); | |
675 | } | |
676 | ||
677 | /* | |
f0eca962 DR |
678 | * See how much we want to round up: start off with |
679 | * rounding to the next 1MB area. | |
a1e97782 | 680 | */ |
f0eca962 DR |
681 | round = 0x100000; |
682 | while ((gapsize >> 4) > round) | |
683 | round += round; | |
684 | /* Fun with two's complement */ | |
685 | pci_mem_start = (gapstart + round) & -round; | |
a1e97782 AK |
686 | |
687 | printk(KERN_INFO "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n", | |
688 | pci_mem_start, gapstart, gapsize); | |
689 | } |