1 #include <linux/kernel.h>
2 #include <linux/types.h>
3 #include <linux/init.h>
4 #include <linux/bootmem.h>
5 #include <linux/ioport.h>
6 #include <linux/string.h>
7 #include <linux/kexec.h>
8 #include <linux/module.h>
10 #include <linux/efi.h>
11 #include <linux/pfn.h>
13 #include <asm/pgtable.h>
19 EXPORT_SYMBOL(efi_enabled);
23 struct change_member {
24 struct e820entry *pbios; /* pointer to original bios entry */
25 unsigned long long addr; /* address for this change point */
27 static struct change_member change_point_list[2*E820MAX] __initdata;
28 static struct change_member *change_point[2*E820MAX] __initdata;
29 static struct e820entry *overlap_list[E820MAX] __initdata;
30 static struct e820entry new_bios[E820MAX] __initdata;
31 /* For PCI or other memory-mapped resources */
32 unsigned long pci_mem_start = 0x10000000;
34 EXPORT_SYMBOL(pci_mem_start);
36 struct resource data_resource = {
37 .name = "Kernel data",
40 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
43 struct resource code_resource = {
44 .name = "Kernel code",
47 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
50 static struct resource system_rom_resource = {
54 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
57 static struct resource extension_rom_resource = {
58 .name = "Extension ROM",
61 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
64 static struct resource adapter_rom_resources[] = { {
65 .name = "Adapter ROM",
68 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
70 .name = "Adapter ROM",
73 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
75 .name = "Adapter ROM",
78 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
80 .name = "Adapter ROM",
83 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
85 .name = "Adapter ROM",
88 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
90 .name = "Adapter ROM",
93 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
96 static struct resource video_rom_resource = {
100 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
103 static struct resource video_ram_resource = {
104 .name = "Video RAM area",
107 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
110 static struct resource standard_io_resources[] = { {
114 .flags = IORESOURCE_BUSY | IORESOURCE_IO
119 .flags = IORESOURCE_BUSY | IORESOURCE_IO
124 .flags = IORESOURCE_BUSY | IORESOURCE_IO
129 .flags = IORESOURCE_BUSY | IORESOURCE_IO
134 .flags = IORESOURCE_BUSY | IORESOURCE_IO
136 .name = "dma page reg",
139 .flags = IORESOURCE_BUSY | IORESOURCE_IO
144 .flags = IORESOURCE_BUSY | IORESOURCE_IO
149 .flags = IORESOURCE_BUSY | IORESOURCE_IO
154 .flags = IORESOURCE_BUSY | IORESOURCE_IO
157 #define romsignature(x) (*(unsigned short *)(x) == 0xaa55)
159 static int __init romchecksum(unsigned char *rom, unsigned long length)
161 unsigned char *p, sum = 0;
163 for (p = rom; p < rom + length; p++)
168 static void __init probe_roms(void)
170 unsigned long start, length, upper;
175 upper = adapter_rom_resources[0].start;
176 for (start = video_rom_resource.start; start < upper; start += 2048) {
177 rom = isa_bus_to_virt(start);
178 if (!romsignature(rom))
181 video_rom_resource.start = start;
183 /* 0 < length <= 0x7f * 512, historically */
184 length = rom[2] * 512;
186 /* if checksum okay, trust length byte */
187 if (length && romchecksum(rom, length))
188 video_rom_resource.end = start + length - 1;
190 request_resource(&iomem_resource, &video_rom_resource);
194 start = (video_rom_resource.end + 1 + 2047) & ~2047UL;
199 request_resource(&iomem_resource, &system_rom_resource);
200 upper = system_rom_resource.start;
202 /* check for extension rom (ignore length byte!) */
203 rom = isa_bus_to_virt(extension_rom_resource.start);
204 if (romsignature(rom)) {
205 length = extension_rom_resource.end - extension_rom_resource.start + 1;
206 if (romchecksum(rom, length)) {
207 request_resource(&iomem_resource, &extension_rom_resource);
208 upper = extension_rom_resource.start;
212 /* check for adapter roms on 2k boundaries */
213 for (i = 0; i < ARRAY_SIZE(adapter_rom_resources) && start < upper; start += 2048) {
214 rom = isa_bus_to_virt(start);
215 if (!romsignature(rom))
218 /* 0 < length <= 0x7f * 512, historically */
219 length = rom[2] * 512;
221 /* but accept any length that fits if checksum okay */
222 if (!length || start + length > upper || !romchecksum(rom, length))
225 adapter_rom_resources[i].start = start;
226 adapter_rom_resources[i].end = start + length - 1;
227 request_resource(&iomem_resource, &adapter_rom_resources[i]);
229 start = adapter_rom_resources[i++].end & ~2047UL;
234 * Request address space for all standard RAM and ROM resources
235 * and also for regions reported as reserved by the e820.
238 legacy_init_iomem_resources(struct resource *code_resource, struct resource *data_resource)
243 for (i = 0; i < e820.nr_map; i++) {
244 struct resource *res;
245 #ifndef CONFIG_RESOURCES_64BIT
246 if (e820.map[i].addr + e820.map[i].size > 0x100000000ULL)
249 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
250 switch (e820.map[i].type) {
251 case E820_RAM: res->name = "System RAM"; break;
252 case E820_ACPI: res->name = "ACPI Tables"; break;
253 case E820_NVS: res->name = "ACPI Non-volatile Storage"; break;
254 default: res->name = "reserved";
256 res->start = e820.map[i].addr;
257 res->end = res->start + e820.map[i].size - 1;
258 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
259 if (request_resource(&iomem_resource, res)) {
263 if (e820.map[i].type == E820_RAM) {
265 * We don't know which RAM region contains kernel data,
266 * so we try it repeatedly and let the resource manager
269 request_resource(res, code_resource);
270 request_resource(res, data_resource);
272 request_resource(res, &crashk_res);
279 * Request address space for all standard resources
281 * This is called just before pcibios_init(), which is also a
282 * subsys_initcall, but is linked in later (in arch/i386/pci/common.c).
284 static int __init request_standard_resources(void)
288 printk("Setting up standard PCI resources\n");
290 efi_initialize_iomem_resources(&code_resource, &data_resource);
292 legacy_init_iomem_resources(&code_resource, &data_resource);
294 /* EFI systems may still have VGA */
295 request_resource(&iomem_resource, &video_ram_resource);
297 /* request I/O space for devices used on all i[345]86 PCs */
298 for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
299 request_resource(&ioport_resource, &standard_io_resources[i]);
303 subsys_initcall(request_standard_resources);
305 void __init add_memory_region(unsigned long long start,
306 unsigned long long size, int type)
314 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
318 e820.map[x].addr = start;
319 e820.map[x].size = size;
320 e820.map[x].type = type;
323 } /* add_memory_region */
326 * Sanitize the BIOS e820 map.
328 * Some e820 responses include overlapping entries. The following
329 * replaces the original e820 map with a new one, removing overlaps.
332 int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map)
334 struct change_member *change_tmp;
335 unsigned long current_type, last_type;
336 unsigned long long last_addr;
337 int chgidx, still_changing;
340 int old_nr, new_nr, chg_nr;
344 Visually we're performing the following (1,2,3,4 = memory types)...
346 Sample memory map (w/overlaps):
347 ____22__________________
348 ______________________4_
349 ____1111________________
350 _44_____________________
351 11111111________________
352 ____________________33__
353 ___________44___________
354 __________33333_________
355 ______________22________
356 ___________________2222_
357 _________111111111______
358 _____________________11_
359 _________________4______
361 Sanitized equivalent (no overlap):
362 1_______________________
363 _44_____________________
364 ___1____________________
365 ____22__________________
366 ______11________________
367 _________1______________
368 __________3_____________
369 ___________44___________
370 _____________33_________
371 _______________2________
372 ________________1_______
373 _________________4______
374 ___________________2____
375 ____________________33__
376 ______________________4_
378 printk("sanitize start\n");
379 /* if there's only one memory region, don't bother */
381 printk("sanitize bail 0\n");
387 /* bail out if we find any unreasonable addresses in bios map */
388 for (i=0; i<old_nr; i++)
389 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr) {
390 printk("sanitize bail 1\n");
394 /* create pointers for initial change-point information (for sorting) */
395 for (i=0; i < 2*old_nr; i++)
396 change_point[i] = &change_point_list[i];
398 /* record all known change-points (starting and ending addresses),
399 omitting those that are for empty memory regions */
401 for (i=0; i < old_nr; i++) {
402 if (biosmap[i].size != 0) {
403 change_point[chgidx]->addr = biosmap[i].addr;
404 change_point[chgidx++]->pbios = &biosmap[i];
405 change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size;
406 change_point[chgidx++]->pbios = &biosmap[i];
409 chg_nr = chgidx; /* true number of change-points */
411 /* sort change-point list by memory addresses (low -> high) */
413 while (still_changing) {
415 for (i=1; i < chg_nr; i++) {
416 /* if <current_addr> > <last_addr>, swap */
417 /* or, if current=<start_addr> & last=<end_addr>, swap */
418 if ((change_point[i]->addr < change_point[i-1]->addr) ||
419 ((change_point[i]->addr == change_point[i-1]->addr) &&
420 (change_point[i]->addr == change_point[i]->pbios->addr) &&
421 (change_point[i-1]->addr != change_point[i-1]->pbios->addr))
424 change_tmp = change_point[i];
425 change_point[i] = change_point[i-1];
426 change_point[i-1] = change_tmp;
432 /* create a new bios memory map, removing overlaps */
433 overlap_entries=0; /* number of entries in the overlap table */
434 new_bios_entry=0; /* index for creating new bios map entries */
435 last_type = 0; /* start with undefined memory type */
436 last_addr = 0; /* start with 0 as last starting address */
437 /* loop through change-points, determining affect on the new bios map */
438 for (chgidx=0; chgidx < chg_nr; chgidx++)
440 /* keep track of all overlapping bios entries */
441 if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr)
443 /* add map entry to overlap list (> 1 entry implies an overlap) */
444 overlap_list[overlap_entries++]=change_point[chgidx]->pbios;
448 /* remove entry from list (order independent, so swap with last) */
449 for (i=0; i<overlap_entries; i++)
451 if (overlap_list[i] == change_point[chgidx]->pbios)
452 overlap_list[i] = overlap_list[overlap_entries-1];
456 /* if there are overlapping entries, decide which "type" to use */
457 /* (larger value takes precedence -- 1=usable, 2,3,4,4+=unusable) */
459 for (i=0; i<overlap_entries; i++)
460 if (overlap_list[i]->type > current_type)
461 current_type = overlap_list[i]->type;
462 /* continue building up new bios map based on this information */
463 if (current_type != last_type) {
464 if (last_type != 0) {
465 new_bios[new_bios_entry].size =
466 change_point[chgidx]->addr - last_addr;
467 /* move forward only if the new size was non-zero */
468 if (new_bios[new_bios_entry].size != 0)
469 if (++new_bios_entry >= E820MAX)
470 break; /* no more space left for new bios entries */
472 if (current_type != 0) {
473 new_bios[new_bios_entry].addr = change_point[chgidx]->addr;
474 new_bios[new_bios_entry].type = current_type;
475 last_addr=change_point[chgidx]->addr;
477 last_type = current_type;
480 new_nr = new_bios_entry; /* retain count for new bios entries */
482 /* copy new bios mapping into original location */
483 memcpy(biosmap, new_bios, new_nr*sizeof(struct e820entry));
486 printk("sanitize end\n");
491 * Copy the BIOS e820 map into a safe place.
493 * Sanity-check it while we're at it..
495 * If we're lucky and live on a modern system, the setup code
496 * will have given us a memory map that we can use to properly
497 * set up memory. If we aren't, we'll fake a memory map.
499 * We check to see that the memory map contains at least 2 elements
500 * before we'll use it, because the detection code in setup.S may
501 * not be perfect and most every PC known to man has two memory
502 * regions: one from 0 to 640k, and one from 1mb up. (The IBM
503 * thinkpad 560x, for example, does not cooperate with the memory
506 int __init copy_e820_map(struct e820entry * biosmap, int nr_map)
508 /* Only one memory region (or negative)? Ignore it */
513 unsigned long long start = biosmap->addr;
514 unsigned long long size = biosmap->size;
515 unsigned long long end = start + size;
516 unsigned long type = biosmap->type;
517 printk("copy_e820_map() start: %016Lx size: %016Lx end: %016Lx type: %ld\n", start, size, end, type);
519 /* Overflow in 64 bits? Ignore the memory map. */
524 * Some BIOSes claim RAM in the 640k - 1M region.
525 * Not right. Fix it up.
527 if (type == E820_RAM) {
528 printk("copy_e820_map() type is E820_RAM\n");
529 if (start < 0x100000ULL && end > 0xA0000ULL) {
530 printk("copy_e820_map() lies in range...\n");
531 if (start < 0xA0000ULL) {
532 printk("copy_e820_map() start < 0xA0000ULL\n");
533 add_memory_region(start, 0xA0000ULL-start, type);
535 if (end <= 0x100000ULL) {
536 printk("copy_e820_map() end <= 0x100000ULL\n");
543 add_memory_region(start, size, type);
544 } while (biosmap++,--nr_map);
549 * Callback for efi_memory_walk.
552 efi_find_max_pfn(unsigned long start, unsigned long end, void *arg)
554 unsigned long *max_pfn = arg, pfn;
557 pfn = PFN_UP(end -1);
565 efi_memory_present_wrapper(unsigned long start, unsigned long end, void *arg)
567 memory_present(0, PFN_UP(start), PFN_DOWN(end));
572 * Find the highest page frame number we have available
574 void __init find_max_pfn(void)
580 efi_memmap_walk(efi_find_max_pfn, &max_pfn);
581 efi_memmap_walk(efi_memory_present_wrapper, NULL);
585 for (i = 0; i < e820.nr_map; i++) {
586 unsigned long start, end;
588 if (e820.map[i].type != E820_RAM)
590 start = PFN_UP(e820.map[i].addr);
591 end = PFN_DOWN(e820.map[i].addr + e820.map[i].size);
596 memory_present(0, start, end);
601 * Free all available memory for boot time allocation. Used
602 * as a callback function by efi_memory_walk()
606 free_available_memory(unsigned long start, unsigned long end, void *arg)
608 /* check max_low_pfn */
609 if (start >= (max_low_pfn << PAGE_SHIFT))
611 if (end >= (max_low_pfn << PAGE_SHIFT))
612 end = max_low_pfn << PAGE_SHIFT;
614 free_bootmem(start, end - start);
619 * Register fully available low RAM pages with the bootmem allocator.
621 void __init register_bootmem_low_pages(unsigned long max_low_pfn)
626 efi_memmap_walk(free_available_memory, NULL);
629 for (i = 0; i < e820.nr_map; i++) {
630 unsigned long curr_pfn, last_pfn, size;
632 * Reserve usable low memory
634 if (e820.map[i].type != E820_RAM)
637 * We are rounding up the start address of usable memory:
639 curr_pfn = PFN_UP(e820.map[i].addr);
640 if (curr_pfn >= max_low_pfn)
643 * ... and at the end of the usable range downwards:
645 last_pfn = PFN_DOWN(e820.map[i].addr + e820.map[i].size);
647 if (last_pfn > max_low_pfn)
648 last_pfn = max_low_pfn;
651 * .. finally, did all the rounding and playing
652 * around just make the area go away?
654 if (last_pfn <= curr_pfn)
657 size = last_pfn - curr_pfn;
658 free_bootmem(PFN_PHYS(curr_pfn), PFN_PHYS(size));
662 void __init register_memory(void)
664 unsigned long gapstart, gapsize, round;
665 unsigned long long last;
669 * Search for the bigest gap in the low 32 bits of the e820
672 last = 0x100000000ull;
673 gapstart = 0x10000000;
677 unsigned long long start = e820.map[i].addr;
678 unsigned long long end = start + e820.map[i].size;
681 * Since "last" is at most 4GB, we know we'll
682 * fit in 32 bits if this condition is true
685 unsigned long gap = last - end;
697 * See how much we want to round up: start off with
698 * rounding to the next 1MB area.
701 while ((gapsize >> 4) > round)
703 /* Fun with two's complement */
704 pci_mem_start = (gapstart + round) & -round;
706 printk("Allocating PCI resources starting at %08lx (gap: %08lx:%08lx)\n",
707 pci_mem_start, gapstart, gapsize);