Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Handle the memory map. | |
3 | * The functions here do the job until bootmem takes over. | |
4 | * $Id: e820.c,v 1.4 2002/09/19 19:25:32 ak Exp $ | |
8059b2a2 VP |
5 | * |
6 | * Getting sanitize_e820_map() in sync with i386 version by applying change: | |
7 | * - Provisions for empty E820 memory regions (reported by certain BIOSes). | |
8 | * Alex Achenbach <xela@slit.de>, December 2002. | |
9 | * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> | |
10 | * | |
1da177e4 LT |
11 | */ |
12 | #include <linux/config.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/types.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/bootmem.h> | |
17 | #include <linux/ioport.h> | |
18 | #include <linux/string.h> | |
5f5609df | 19 | #include <linux/kexec.h> |
1da177e4 LT |
20 | #include <asm/page.h> |
21 | #include <asm/e820.h> | |
22 | #include <asm/proto.h> | |
23 | #include <asm/bootsetup.h> | |
24 | ||
25 | extern char _end[]; | |
26 | ||
27 | /* | |
28 | * PFN of last memory page. | |
29 | */ | |
30 | unsigned long end_pfn; | |
31 | ||
32 | /* | |
33 | * end_pfn only includes RAM, while end_pfn_map includes all e820 entries. | |
34 | * The direct mapping extends to end_pfn_map, so that we can directly access | |
35 | * apertures, ACPI and other tables without having to play with fixmaps. | |
36 | */ | |
37 | unsigned long end_pfn_map; | |
38 | ||
39 | /* | |
40 | * Last pfn which the user wants to use. | |
41 | */ | |
42 | unsigned long end_user_pfn = MAXMEM>>PAGE_SHIFT; | |
43 | ||
44 | extern struct resource code_resource, data_resource; | |
45 | ||
46 | /* Check for some hardcoded bad areas that early boot is not allowed to touch */ | |
47 | static inline int bad_addr(unsigned long *addrp, unsigned long size) | |
48 | { | |
49 | unsigned long addr = *addrp, last = addr + size; | |
50 | ||
51 | /* various gunk below that needed for SMP startup */ | |
52 | if (addr < 0x8000) { | |
53 | *addrp = 0x8000; | |
54 | return 1; | |
55 | } | |
56 | ||
57 | /* direct mapping tables of the kernel */ | |
58 | if (last >= table_start<<PAGE_SHIFT && addr < table_end<<PAGE_SHIFT) { | |
59 | *addrp = table_end << PAGE_SHIFT; | |
60 | return 1; | |
61 | } | |
62 | ||
63 | /* initrd */ | |
64 | #ifdef CONFIG_BLK_DEV_INITRD | |
65 | if (LOADER_TYPE && INITRD_START && last >= INITRD_START && | |
66 | addr < INITRD_START+INITRD_SIZE) { | |
67 | *addrp = INITRD_START + INITRD_SIZE; | |
68 | return 1; | |
69 | } | |
70 | #endif | |
71 | /* kernel code + 640k memory hole (later should not be needed, but | |
72 | be paranoid for now) */ | |
73 | if (last >= 640*1024 && addr < __pa_symbol(&_end)) { | |
74 | *addrp = __pa_symbol(&_end); | |
75 | return 1; | |
76 | } | |
77 | /* XXX ramdisk image here? */ | |
78 | return 0; | |
79 | } | |
80 | ||
81 | int __init e820_mapped(unsigned long start, unsigned long end, unsigned type) | |
82 | { | |
83 | int i; | |
84 | for (i = 0; i < e820.nr_map; i++) { | |
85 | struct e820entry *ei = &e820.map[i]; | |
86 | if (type && ei->type != type) | |
87 | continue; | |
48c8b113 | 88 | if (ei->addr >= end || ei->addr + ei->size <= start) |
1da177e4 LT |
89 | continue; |
90 | return 1; | |
91 | } | |
92 | return 0; | |
93 | } | |
94 | ||
95 | /* | |
96 | * Find a free area in a specific range. | |
97 | */ | |
98 | unsigned long __init find_e820_area(unsigned long start, unsigned long end, unsigned size) | |
99 | { | |
100 | int i; | |
101 | for (i = 0; i < e820.nr_map; i++) { | |
102 | struct e820entry *ei = &e820.map[i]; | |
103 | unsigned long addr = ei->addr, last; | |
104 | if (ei->type != E820_RAM) | |
105 | continue; | |
106 | if (addr < start) | |
107 | addr = start; | |
108 | if (addr > ei->addr + ei->size) | |
109 | continue; | |
110 | while (bad_addr(&addr, size) && addr+size < ei->addr + ei->size) | |
111 | ; | |
112 | last = addr + size; | |
113 | if (last > ei->addr + ei->size) | |
114 | continue; | |
115 | if (last > end) | |
116 | continue; | |
117 | return addr; | |
118 | } | |
119 | return -1UL; | |
120 | } | |
121 | ||
122 | /* | |
123 | * Free bootmem based on the e820 table for a node. | |
124 | */ | |
125 | void __init e820_bootmem_free(pg_data_t *pgdat, unsigned long start,unsigned long end) | |
126 | { | |
127 | int i; | |
128 | for (i = 0; i < e820.nr_map; i++) { | |
129 | struct e820entry *ei = &e820.map[i]; | |
130 | unsigned long last, addr; | |
131 | ||
132 | if (ei->type != E820_RAM || | |
133 | ei->addr+ei->size <= start || | |
7c7a3897 | 134 | ei->addr >= end) |
1da177e4 LT |
135 | continue; |
136 | ||
137 | addr = round_up(ei->addr, PAGE_SIZE); | |
138 | if (addr < start) | |
139 | addr = start; | |
140 | ||
141 | last = round_down(ei->addr + ei->size, PAGE_SIZE); | |
142 | if (last >= end) | |
143 | last = end; | |
144 | ||
145 | if (last > addr && last-addr >= PAGE_SIZE) | |
146 | free_bootmem_node(pgdat, addr, last-addr); | |
147 | } | |
148 | } | |
149 | ||
150 | /* | |
151 | * Find the highest page frame number we have available | |
152 | */ | |
153 | unsigned long __init e820_end_of_ram(void) | |
154 | { | |
155 | int i; | |
156 | unsigned long end_pfn = 0; | |
157 | ||
158 | for (i = 0; i < e820.nr_map; i++) { | |
159 | struct e820entry *ei = &e820.map[i]; | |
160 | unsigned long start, end; | |
161 | ||
162 | start = round_up(ei->addr, PAGE_SIZE); | |
163 | end = round_down(ei->addr + ei->size, PAGE_SIZE); | |
164 | if (start >= end) | |
165 | continue; | |
166 | if (ei->type == E820_RAM) { | |
167 | if (end > end_pfn<<PAGE_SHIFT) | |
168 | end_pfn = end>>PAGE_SHIFT; | |
169 | } else { | |
170 | if (end > end_pfn_map<<PAGE_SHIFT) | |
171 | end_pfn_map = end>>PAGE_SHIFT; | |
172 | } | |
173 | } | |
174 | ||
175 | if (end_pfn > end_pfn_map) | |
176 | end_pfn_map = end_pfn; | |
177 | if (end_pfn_map > MAXMEM>>PAGE_SHIFT) | |
178 | end_pfn_map = MAXMEM>>PAGE_SHIFT; | |
179 | if (end_pfn > end_user_pfn) | |
180 | end_pfn = end_user_pfn; | |
181 | if (end_pfn > end_pfn_map) | |
182 | end_pfn = end_pfn_map; | |
183 | ||
184 | return end_pfn; | |
185 | } | |
186 | ||
187 | /* | |
485761bd AK |
188 | * Compute how much memory is missing in a range. |
189 | * Unlike the other functions in this file the arguments are in page numbers. | |
190 | */ | |
191 | unsigned long __init | |
192 | e820_hole_size(unsigned long start_pfn, unsigned long end_pfn) | |
193 | { | |
194 | unsigned long ram = 0; | |
195 | unsigned long start = start_pfn << PAGE_SHIFT; | |
196 | unsigned long end = end_pfn << PAGE_SHIFT; | |
197 | int i; | |
198 | for (i = 0; i < e820.nr_map; i++) { | |
199 | struct e820entry *ei = &e820.map[i]; | |
200 | unsigned long last, addr; | |
201 | ||
202 | if (ei->type != E820_RAM || | |
203 | ei->addr+ei->size <= start || | |
204 | ei->addr >= end) | |
205 | continue; | |
206 | ||
207 | addr = round_up(ei->addr, PAGE_SIZE); | |
208 | if (addr < start) | |
209 | addr = start; | |
210 | ||
211 | last = round_down(ei->addr + ei->size, PAGE_SIZE); | |
212 | if (last >= end) | |
213 | last = end; | |
214 | ||
215 | if (last > addr) | |
216 | ram += last - addr; | |
217 | } | |
218 | return ((end - start) - ram) >> PAGE_SHIFT; | |
219 | } | |
220 | ||
221 | /* | |
1da177e4 LT |
222 | * Mark e820 reserved areas as busy for the resource manager. |
223 | */ | |
224 | void __init e820_reserve_resources(void) | |
225 | { | |
226 | int i; | |
227 | for (i = 0; i < e820.nr_map; i++) { | |
228 | struct resource *res; | |
1da177e4 LT |
229 | res = alloc_bootmem_low(sizeof(struct resource)); |
230 | switch (e820.map[i].type) { | |
231 | case E820_RAM: res->name = "System RAM"; break; | |
232 | case E820_ACPI: res->name = "ACPI Tables"; break; | |
233 | case E820_NVS: res->name = "ACPI Non-volatile Storage"; break; | |
234 | default: res->name = "reserved"; | |
235 | } | |
236 | res->start = e820.map[i].addr; | |
237 | res->end = res->start + e820.map[i].size - 1; | |
238 | res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; | |
239 | request_resource(&iomem_resource, res); | |
240 | if (e820.map[i].type == E820_RAM) { | |
241 | /* | |
242 | * We don't know which RAM region contains kernel data, | |
243 | * so we try it repeatedly and let the resource manager | |
244 | * test it. | |
245 | */ | |
246 | request_resource(res, &code_resource); | |
247 | request_resource(res, &data_resource); | |
5f5609df EB |
248 | #ifdef CONFIG_KEXEC |
249 | request_resource(res, &crashk_res); | |
250 | #endif | |
1da177e4 LT |
251 | } |
252 | } | |
253 | } | |
254 | ||
255 | /* | |
256 | * Add a memory region to the kernel e820 map. | |
257 | */ | |
258 | void __init add_memory_region(unsigned long start, unsigned long size, int type) | |
259 | { | |
260 | int x = e820.nr_map; | |
261 | ||
262 | if (x == E820MAX) { | |
263 | printk(KERN_ERR "Ooops! Too many entries in the memory map!\n"); | |
264 | return; | |
265 | } | |
266 | ||
267 | e820.map[x].addr = start; | |
268 | e820.map[x].size = size; | |
269 | e820.map[x].type = type; | |
270 | e820.nr_map++; | |
271 | } | |
272 | ||
273 | void __init e820_print_map(char *who) | |
274 | { | |
275 | int i; | |
276 | ||
277 | for (i = 0; i < e820.nr_map; i++) { | |
278 | printk(" %s: %016Lx - %016Lx ", who, | |
279 | (unsigned long long) e820.map[i].addr, | |
280 | (unsigned long long) (e820.map[i].addr + e820.map[i].size)); | |
281 | switch (e820.map[i].type) { | |
282 | case E820_RAM: printk("(usable)\n"); | |
283 | break; | |
284 | case E820_RESERVED: | |
285 | printk("(reserved)\n"); | |
286 | break; | |
287 | case E820_ACPI: | |
288 | printk("(ACPI data)\n"); | |
289 | break; | |
290 | case E820_NVS: | |
291 | printk("(ACPI NVS)\n"); | |
292 | break; | |
293 | default: printk("type %u\n", e820.map[i].type); | |
294 | break; | |
295 | } | |
296 | } | |
297 | } | |
298 | ||
299 | /* | |
300 | * Sanitize the BIOS e820 map. | |
301 | * | |
302 | * Some e820 responses include overlapping entries. The following | |
303 | * replaces the original e820 map with a new one, removing overlaps. | |
304 | * | |
305 | */ | |
306 | static int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map) | |
307 | { | |
308 | struct change_member { | |
309 | struct e820entry *pbios; /* pointer to original bios entry */ | |
310 | unsigned long long addr; /* address for this change point */ | |
311 | }; | |
312 | static struct change_member change_point_list[2*E820MAX] __initdata; | |
313 | static struct change_member *change_point[2*E820MAX] __initdata; | |
314 | static struct e820entry *overlap_list[E820MAX] __initdata; | |
315 | static struct e820entry new_bios[E820MAX] __initdata; | |
316 | struct change_member *change_tmp; | |
317 | unsigned long current_type, last_type; | |
318 | unsigned long long last_addr; | |
319 | int chgidx, still_changing; | |
320 | int overlap_entries; | |
321 | int new_bios_entry; | |
8059b2a2 | 322 | int old_nr, new_nr, chg_nr; |
1da177e4 LT |
323 | int i; |
324 | ||
325 | /* | |
326 | Visually we're performing the following (1,2,3,4 = memory types)... | |
327 | ||
328 | Sample memory map (w/overlaps): | |
329 | ____22__________________ | |
330 | ______________________4_ | |
331 | ____1111________________ | |
332 | _44_____________________ | |
333 | 11111111________________ | |
334 | ____________________33__ | |
335 | ___________44___________ | |
336 | __________33333_________ | |
337 | ______________22________ | |
338 | ___________________2222_ | |
339 | _________111111111______ | |
340 | _____________________11_ | |
341 | _________________4______ | |
342 | ||
343 | Sanitized equivalent (no overlap): | |
344 | 1_______________________ | |
345 | _44_____________________ | |
346 | ___1____________________ | |
347 | ____22__________________ | |
348 | ______11________________ | |
349 | _________1______________ | |
350 | __________3_____________ | |
351 | ___________44___________ | |
352 | _____________33_________ | |
353 | _______________2________ | |
354 | ________________1_______ | |
355 | _________________4______ | |
356 | ___________________2____ | |
357 | ____________________33__ | |
358 | ______________________4_ | |
359 | */ | |
360 | ||
361 | /* if there's only one memory region, don't bother */ | |
362 | if (*pnr_map < 2) | |
363 | return -1; | |
364 | ||
365 | old_nr = *pnr_map; | |
366 | ||
367 | /* bail out if we find any unreasonable addresses in bios map */ | |
368 | for (i=0; i<old_nr; i++) | |
369 | if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr) | |
370 | return -1; | |
371 | ||
372 | /* create pointers for initial change-point information (for sorting) */ | |
373 | for (i=0; i < 2*old_nr; i++) | |
374 | change_point[i] = &change_point_list[i]; | |
375 | ||
8059b2a2 VP |
376 | /* record all known change-points (starting and ending addresses), |
377 | omitting those that are for empty memory regions */ | |
1da177e4 LT |
378 | chgidx = 0; |
379 | for (i=0; i < old_nr; i++) { | |
8059b2a2 VP |
380 | if (biosmap[i].size != 0) { |
381 | change_point[chgidx]->addr = biosmap[i].addr; | |
382 | change_point[chgidx++]->pbios = &biosmap[i]; | |
383 | change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size; | |
384 | change_point[chgidx++]->pbios = &biosmap[i]; | |
385 | } | |
1da177e4 | 386 | } |
8059b2a2 | 387 | chg_nr = chgidx; |
1da177e4 LT |
388 | |
389 | /* sort change-point list by memory addresses (low -> high) */ | |
390 | still_changing = 1; | |
391 | while (still_changing) { | |
392 | still_changing = 0; | |
8059b2a2 | 393 | for (i=1; i < chg_nr; i++) { |
1da177e4 LT |
394 | /* if <current_addr> > <last_addr>, swap */ |
395 | /* or, if current=<start_addr> & last=<end_addr>, swap */ | |
396 | if ((change_point[i]->addr < change_point[i-1]->addr) || | |
397 | ((change_point[i]->addr == change_point[i-1]->addr) && | |
398 | (change_point[i]->addr == change_point[i]->pbios->addr) && | |
399 | (change_point[i-1]->addr != change_point[i-1]->pbios->addr)) | |
400 | ) | |
401 | { | |
402 | change_tmp = change_point[i]; | |
403 | change_point[i] = change_point[i-1]; | |
404 | change_point[i-1] = change_tmp; | |
405 | still_changing=1; | |
406 | } | |
407 | } | |
408 | } | |
409 | ||
410 | /* create a new bios memory map, removing overlaps */ | |
411 | overlap_entries=0; /* number of entries in the overlap table */ | |
412 | new_bios_entry=0; /* index for creating new bios map entries */ | |
413 | last_type = 0; /* start with undefined memory type */ | |
414 | last_addr = 0; /* start with 0 as last starting address */ | |
415 | /* loop through change-points, determining affect on the new bios map */ | |
8059b2a2 | 416 | for (chgidx=0; chgidx < chg_nr; chgidx++) |
1da177e4 LT |
417 | { |
418 | /* keep track of all overlapping bios entries */ | |
419 | if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr) | |
420 | { | |
421 | /* add map entry to overlap list (> 1 entry implies an overlap) */ | |
422 | overlap_list[overlap_entries++]=change_point[chgidx]->pbios; | |
423 | } | |
424 | else | |
425 | { | |
426 | /* remove entry from list (order independent, so swap with last) */ | |
427 | for (i=0; i<overlap_entries; i++) | |
428 | { | |
429 | if (overlap_list[i] == change_point[chgidx]->pbios) | |
430 | overlap_list[i] = overlap_list[overlap_entries-1]; | |
431 | } | |
432 | overlap_entries--; | |
433 | } | |
434 | /* if there are overlapping entries, decide which "type" to use */ | |
435 | /* (larger value takes precedence -- 1=usable, 2,3,4,4+=unusable) */ | |
436 | current_type = 0; | |
437 | for (i=0; i<overlap_entries; i++) | |
438 | if (overlap_list[i]->type > current_type) | |
439 | current_type = overlap_list[i]->type; | |
440 | /* continue building up new bios map based on this information */ | |
441 | if (current_type != last_type) { | |
442 | if (last_type != 0) { | |
443 | new_bios[new_bios_entry].size = | |
444 | change_point[chgidx]->addr - last_addr; | |
445 | /* move forward only if the new size was non-zero */ | |
446 | if (new_bios[new_bios_entry].size != 0) | |
447 | if (++new_bios_entry >= E820MAX) | |
448 | break; /* no more space left for new bios entries */ | |
449 | } | |
450 | if (current_type != 0) { | |
451 | new_bios[new_bios_entry].addr = change_point[chgidx]->addr; | |
452 | new_bios[new_bios_entry].type = current_type; | |
453 | last_addr=change_point[chgidx]->addr; | |
454 | } | |
455 | last_type = current_type; | |
456 | } | |
457 | } | |
458 | new_nr = new_bios_entry; /* retain count for new bios entries */ | |
459 | ||
460 | /* copy new bios mapping into original location */ | |
461 | memcpy(biosmap, new_bios, new_nr*sizeof(struct e820entry)); | |
462 | *pnr_map = new_nr; | |
463 | ||
464 | return 0; | |
465 | } | |
466 | ||
467 | /* | |
468 | * Copy the BIOS e820 map into a safe place. | |
469 | * | |
470 | * Sanity-check it while we're at it.. | |
471 | * | |
472 | * If we're lucky and live on a modern system, the setup code | |
473 | * will have given us a memory map that we can use to properly | |
474 | * set up memory. If we aren't, we'll fake a memory map. | |
475 | * | |
476 | * We check to see that the memory map contains at least 2 elements | |
477 | * before we'll use it, because the detection code in setup.S may | |
478 | * not be perfect and most every PC known to man has two memory | |
479 | * regions: one from 0 to 640k, and one from 1mb up. (The IBM | |
480 | * thinkpad 560x, for example, does not cooperate with the memory | |
481 | * detection code.) | |
482 | */ | |
483 | static int __init copy_e820_map(struct e820entry * biosmap, int nr_map) | |
484 | { | |
485 | /* Only one memory region (or negative)? Ignore it */ | |
486 | if (nr_map < 2) | |
487 | return -1; | |
488 | ||
489 | do { | |
490 | unsigned long start = biosmap->addr; | |
491 | unsigned long size = biosmap->size; | |
492 | unsigned long end = start + size; | |
493 | unsigned long type = biosmap->type; | |
494 | ||
495 | /* Overflow in 64 bits? Ignore the memory map. */ | |
496 | if (start > end) | |
497 | return -1; | |
498 | ||
499 | /* | |
500 | * Some BIOSes claim RAM in the 640k - 1M region. | |
501 | * Not right. Fix it up. | |
502 | * | |
503 | * This should be removed on Hammer which is supposed to not | |
504 | * have non e820 covered ISA mappings there, but I had some strange | |
505 | * problems so it stays for now. -AK | |
506 | */ | |
507 | if (type == E820_RAM) { | |
508 | if (start < 0x100000ULL && end > 0xA0000ULL) { | |
509 | if (start < 0xA0000ULL) | |
510 | add_memory_region(start, 0xA0000ULL-start, type); | |
511 | if (end <= 0x100000ULL) | |
512 | continue; | |
513 | start = 0x100000ULL; | |
514 | size = end - start; | |
515 | } | |
516 | } | |
517 | ||
518 | add_memory_region(start, size, type); | |
519 | } while (biosmap++,--nr_map); | |
520 | return 0; | |
521 | } | |
522 | ||
523 | void __init setup_memory_region(void) | |
524 | { | |
525 | char *who = "BIOS-e820"; | |
526 | ||
527 | /* | |
528 | * Try to copy the BIOS-supplied E820-map. | |
529 | * | |
530 | * Otherwise fake a memory map; one section from 0k->640k, | |
531 | * the next section from 1mb->appropriate_mem_k | |
532 | */ | |
533 | sanitize_e820_map(E820_MAP, &E820_MAP_NR); | |
534 | if (copy_e820_map(E820_MAP, E820_MAP_NR) < 0) { | |
535 | unsigned long mem_size; | |
536 | ||
537 | /* compare results from other methods and take the greater */ | |
538 | if (ALT_MEM_K < EXT_MEM_K) { | |
539 | mem_size = EXT_MEM_K; | |
540 | who = "BIOS-88"; | |
541 | } else { | |
542 | mem_size = ALT_MEM_K; | |
543 | who = "BIOS-e801"; | |
544 | } | |
545 | ||
546 | e820.nr_map = 0; | |
547 | add_memory_region(0, LOWMEMSIZE(), E820_RAM); | |
548 | add_memory_region(HIGH_MEMORY, mem_size << 10, E820_RAM); | |
549 | } | |
550 | printk(KERN_INFO "BIOS-provided physical RAM map:\n"); | |
551 | e820_print_map(who); | |
552 | } | |
553 | ||
554 | void __init parse_memopt(char *p, char **from) | |
555 | { | |
556 | end_user_pfn = memparse(p, from); | |
557 | end_user_pfn >>= PAGE_SHIFT; | |
558 | } | |
559 | ||
a1e97782 AK |
560 | unsigned long pci_mem_start = 0xaeedbabe; |
561 | ||
562 | /* | |
563 | * Search for the biggest gap in the low 32 bits of the e820 | |
564 | * memory space. We pass this space to PCI to assign MMIO resources | |
565 | * for hotplug or unconfigured devices in. | |
566 | * Hopefully the BIOS let enough space left. | |
567 | */ | |
568 | __init void e820_setup_gap(void) | |
569 | { | |
f0eca962 | 570 | unsigned long gapstart, gapsize, round; |
a1e97782 AK |
571 | unsigned long last; |
572 | int i; | |
573 | int found = 0; | |
574 | ||
575 | last = 0x100000000ull; | |
576 | gapstart = 0x10000000; | |
577 | gapsize = 0x400000; | |
578 | i = e820.nr_map; | |
579 | while (--i >= 0) { | |
580 | unsigned long long start = e820.map[i].addr; | |
581 | unsigned long long end = start + e820.map[i].size; | |
582 | ||
583 | /* | |
584 | * Since "last" is at most 4GB, we know we'll | |
585 | * fit in 32 bits if this condition is true | |
586 | */ | |
587 | if (last > end) { | |
588 | unsigned long gap = last - end; | |
589 | ||
590 | if (gap > gapsize) { | |
591 | gapsize = gap; | |
592 | gapstart = end; | |
593 | found = 1; | |
594 | } | |
595 | } | |
596 | if (start < last) | |
597 | last = start; | |
598 | } | |
599 | ||
600 | if (!found) { | |
601 | gapstart = (end_pfn << PAGE_SHIFT) + 1024*1024; | |
602 | printk(KERN_ERR "PCI: Warning: Cannot find a gap in the 32bit address range\n" | |
603 | KERN_ERR "PCI: Unassigned devices with 32bit resource registers may break!\n"); | |
604 | } | |
605 | ||
606 | /* | |
f0eca962 DR |
607 | * See how much we want to round up: start off with |
608 | * rounding to the next 1MB area. | |
a1e97782 | 609 | */ |
f0eca962 DR |
610 | round = 0x100000; |
611 | while ((gapsize >> 4) > round) | |
612 | round += round; | |
613 | /* Fun with two's complement */ | |
614 | pci_mem_start = (gapstart + round) & -round; | |
a1e97782 AK |
615 | |
616 | printk(KERN_INFO "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n", | |
617 | pci_mem_start, gapstart, gapsize); | |
618 | } |