xref: /linux/arch/x86/kernel/setup.c (revision 61d0b5a4b2777dcf5daef245e212b3c1fa8091ca)
1 /*
2  *  Copyright (C) 1995  Linus Torvalds
3  *
4  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
5  *
6  *  Memory region support
7  *	David Parsons <orc@pell.chi.il.us>, July-August 1999
8  *
9  *  Added E820 sanitization routine (removes overlapping memory regions);
10  *  Brian Moyle <bmoyle@mvista.com>, February 2001
11  *
12  * Moved CPU detection code to cpu/${cpu}.c
13  *    Patrick Mochel <mochel@osdl.org>, March 2002
14  *
15  *  Provisions for empty E820 memory regions (reported by certain BIOSes).
16  *  Alex Achenbach <xela@slit.de>, December 2002.
17  *
18  */
19 
20 /*
21  * This file handles the architecture-dependent parts of initialization
22  */
23 
24 #include <linux/sched.h>
25 #include <linux/mm.h>
26 #include <linux/mmzone.h>
27 #include <linux/screen_info.h>
28 #include <linux/ioport.h>
29 #include <linux/acpi.h>
30 #include <linux/sfi.h>
31 #include <linux/apm_bios.h>
32 #include <linux/initrd.h>
33 #include <linux/bootmem.h>
34 #include <linux/memblock.h>
35 #include <linux/seq_file.h>
36 #include <linux/console.h>
37 #include <linux/root_dev.h>
38 #include <linux/highmem.h>
39 #include <linux/module.h>
40 #include <linux/efi.h>
41 #include <linux/init.h>
42 #include <linux/edd.h>
43 #include <linux/iscsi_ibft.h>
44 #include <linux/nodemask.h>
45 #include <linux/kexec.h>
46 #include <linux/dmi.h>
47 #include <linux/pfn.h>
48 #include <linux/pci.h>
49 #include <asm/pci-direct.h>
50 #include <linux/init_ohci1394_dma.h>
51 #include <linux/kvm_para.h>
52 #include <linux/dma-contiguous.h>
53 
54 #include <linux/errno.h>
55 #include <linux/kernel.h>
56 #include <linux/stddef.h>
57 #include <linux/unistd.h>
58 #include <linux/ptrace.h>
59 #include <linux/user.h>
60 #include <linux/delay.h>
61 
62 #include <linux/kallsyms.h>
63 #include <linux/cpufreq.h>
64 #include <linux/dma-mapping.h>
65 #include <linux/ctype.h>
66 #include <linux/uaccess.h>
67 
68 #include <linux/percpu.h>
69 #include <linux/crash_dump.h>
70 #include <linux/tboot.h>
71 #include <linux/jiffies.h>
72 
73 #include <video/edid.h>
74 
75 #include <asm/mtrr.h>
76 #include <asm/apic.h>
77 #include <asm/realmode.h>
78 #include <asm/e820.h>
79 #include <asm/mpspec.h>
80 #include <asm/setup.h>
81 #include <asm/efi.h>
82 #include <asm/timer.h>
83 #include <asm/i8259.h>
84 #include <asm/sections.h>
85 #include <asm/dmi.h>
86 #include <asm/io_apic.h>
87 #include <asm/ist.h>
88 #include <asm/setup_arch.h>
89 #include <asm/bios_ebda.h>
90 #include <asm/cacheflush.h>
91 #include <asm/processor.h>
92 #include <asm/bugs.h>
93 
94 #include <asm/vsyscall.h>
95 #include <asm/cpu.h>
96 #include <asm/desc.h>
97 #include <asm/dma.h>
98 #include <asm/iommu.h>
99 #include <asm/gart.h>
100 #include <asm/mmu_context.h>
101 #include <asm/proto.h>
102 
103 #include <asm/paravirt.h>
104 #include <asm/hypervisor.h>
105 #include <asm/olpc_ofw.h>
106 
107 #include <asm/percpu.h>
108 #include <asm/topology.h>
109 #include <asm/apicdef.h>
110 #include <asm/amd_nb.h>
111 #include <asm/mce.h>
112 #include <asm/alternative.h>
113 #include <asm/prom.h>
114 
115 /*
116  * max_low_pfn_mapped: highest direct mapped pfn under 4GB
117  * max_pfn_mapped:     highest direct mapped pfn over 4GB
118  *
119  * The direct mapping only covers E820_RAM regions, so the ranges and gaps are
120  * represented by pfn_mapped
121  */
122 unsigned long max_low_pfn_mapped;
123 unsigned long max_pfn_mapped;
124 
125 #ifdef CONFIG_DMI
126 RESERVE_BRK(dmi_alloc, 65536);
127 #endif
128 
129 
130 static __initdata unsigned long _brk_start = (unsigned long)__brk_base;
131 unsigned long _brk_end = (unsigned long)__brk_base;
132 
133 #ifdef CONFIG_X86_64
134 int default_cpu_present_to_apicid(int mps_cpu)
135 {
136 	return __default_cpu_present_to_apicid(mps_cpu);
137 }
138 
139 int default_check_phys_apicid_present(int phys_apicid)
140 {
141 	return __default_check_phys_apicid_present(phys_apicid);
142 }
143 #endif
144 
145 struct boot_params boot_params;
146 
147 /*
148  * Machine setup..
149  */
150 static struct resource data_resource = {
151 	.name	= "Kernel data",
152 	.start	= 0,
153 	.end	= 0,
154 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
155 };
156 
157 static struct resource code_resource = {
158 	.name	= "Kernel code",
159 	.start	= 0,
160 	.end	= 0,
161 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
162 };
163 
164 static struct resource bss_resource = {
165 	.name	= "Kernel bss",
166 	.start	= 0,
167 	.end	= 0,
168 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
169 };
170 
171 
172 #ifdef CONFIG_X86_32
173 /* cpu data as detected by the assembly code in head.S */
174 struct cpuinfo_x86 new_cpu_data __cpuinitdata = {0, 0, 0, 0, -1, 1, 0, 0, -1};
175 /* common cpu data for all cpus */
176 struct cpuinfo_x86 boot_cpu_data __read_mostly = {0, 0, 0, 0, -1, 1, 0, 0, -1};
177 EXPORT_SYMBOL(boot_cpu_data);
178 
179 unsigned int def_to_bigsmp;
180 
181 /* for MCA, but anyone else can use it if they want */
182 unsigned int machine_id;
183 unsigned int machine_submodel_id;
184 unsigned int BIOS_revision;
185 
186 struct apm_info apm_info;
187 EXPORT_SYMBOL(apm_info);
188 
189 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
190 	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
191 struct ist_info ist_info;
192 EXPORT_SYMBOL(ist_info);
193 #else
194 struct ist_info ist_info;
195 #endif
196 
197 #else
198 struct cpuinfo_x86 boot_cpu_data __read_mostly = {
199 	.x86_phys_bits = MAX_PHYSMEM_BITS,
200 };
201 EXPORT_SYMBOL(boot_cpu_data);
202 #endif
203 
204 
205 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
206 unsigned long mmu_cr4_features;
207 #else
208 unsigned long mmu_cr4_features = X86_CR4_PAE;
209 #endif
210 
211 /* Boot loader ID and version as integers, for the benefit of proc_dointvec */
212 int bootloader_type, bootloader_version;
213 
214 /*
215  * Setup options
216  */
217 struct screen_info screen_info;
218 EXPORT_SYMBOL(screen_info);
219 struct edid_info edid_info;
220 EXPORT_SYMBOL_GPL(edid_info);
221 
222 extern int root_mountflags;
223 
224 unsigned long saved_video_mode;
225 
226 #define RAMDISK_IMAGE_START_MASK	0x07FF
227 #define RAMDISK_PROMPT_FLAG		0x8000
228 #define RAMDISK_LOAD_FLAG		0x4000
229 
230 static char __initdata command_line[COMMAND_LINE_SIZE];
231 #ifdef CONFIG_CMDLINE_BOOL
232 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
233 #endif
234 
235 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
236 struct edd edd;
237 #ifdef CONFIG_EDD_MODULE
238 EXPORT_SYMBOL(edd);
239 #endif
240 /**
241  * copy_edd() - Copy the BIOS EDD information
242  *              from boot_params into a safe place.
243  *
244  */
245 static inline void __init copy_edd(void)
246 {
247      memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
248 	    sizeof(edd.mbr_signature));
249      memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
250      edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
251      edd.edd_info_nr = boot_params.eddbuf_entries;
252 }
253 #else
254 static inline void __init copy_edd(void)
255 {
256 }
257 #endif
258 
259 void * __init extend_brk(size_t size, size_t align)
260 {
261 	size_t mask = align - 1;
262 	void *ret;
263 
264 	BUG_ON(_brk_start == 0);
265 	BUG_ON(align & mask);
266 
267 	_brk_end = (_brk_end + mask) & ~mask;
268 	BUG_ON((char *)(_brk_end + size) > __brk_limit);
269 
270 	ret = (void *)_brk_end;
271 	_brk_end += size;
272 
273 	memset(ret, 0, size);
274 
275 	return ret;
276 }
277 
278 #ifdef CONFIG_X86_32
279 static void __init cleanup_highmap(void)
280 {
281 }
282 #endif
283 
284 static void __init reserve_brk(void)
285 {
286 	if (_brk_end > _brk_start)
287 		memblock_reserve(__pa_symbol(_brk_start),
288 				 _brk_end - _brk_start);
289 
290 	/* Mark brk area as locked down and no longer taking any
291 	   new allocations */
292 	_brk_start = 0;
293 }
294 
295 #ifdef CONFIG_BLK_DEV_INITRD
296 
297 static u64 __init get_ramdisk_image(void)
298 {
299 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
300 
301 	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
302 
303 	return ramdisk_image;
304 }
305 static u64 __init get_ramdisk_size(void)
306 {
307 	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
308 
309 	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
310 
311 	return ramdisk_size;
312 }
313 
314 #define MAX_MAP_CHUNK	(NR_FIX_BTMAPS << PAGE_SHIFT)
315 static void __init relocate_initrd(void)
316 {
317 	/* Assume only end is not page aligned */
318 	u64 ramdisk_image = get_ramdisk_image();
319 	u64 ramdisk_size  = get_ramdisk_size();
320 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
321 	u64 ramdisk_here;
322 	unsigned long slop, clen, mapaddr;
323 	char *p, *q;
324 
325 	/* We need to move the initrd down into directly mapped mem */
326 	ramdisk_here = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
327 						 area_size, PAGE_SIZE);
328 
329 	if (!ramdisk_here)
330 		panic("Cannot find place for new RAMDISK of size %lld\n",
331 			 ramdisk_size);
332 
333 	/* Note: this includes all the mem currently occupied by
334 	   the initrd, we rely on that fact to keep the data intact. */
335 	memblock_reserve(ramdisk_here, area_size);
336 	initrd_start = ramdisk_here + PAGE_OFFSET;
337 	initrd_end   = initrd_start + ramdisk_size;
338 	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
339 			 ramdisk_here, ramdisk_here + ramdisk_size - 1);
340 
341 	q = (char *)initrd_start;
342 
343 	/* Copy the initrd */
344 	while (ramdisk_size) {
345 		slop = ramdisk_image & ~PAGE_MASK;
346 		clen = ramdisk_size;
347 		if (clen > MAX_MAP_CHUNK-slop)
348 			clen = MAX_MAP_CHUNK-slop;
349 		mapaddr = ramdisk_image & PAGE_MASK;
350 		p = early_memremap(mapaddr, clen+slop);
351 		memcpy(q, p+slop, clen);
352 		early_iounmap(p, clen+slop);
353 		q += clen;
354 		ramdisk_image += clen;
355 		ramdisk_size  -= clen;
356 	}
357 
358 	ramdisk_image = get_ramdisk_image();
359 	ramdisk_size  = get_ramdisk_size();
360 	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
361 		" [mem %#010llx-%#010llx]\n",
362 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
363 		ramdisk_here, ramdisk_here + ramdisk_size - 1);
364 }
365 
366 static void __init early_reserve_initrd(void)
367 {
368 	/* Assume only end is not page aligned */
369 	u64 ramdisk_image = get_ramdisk_image();
370 	u64 ramdisk_size  = get_ramdisk_size();
371 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
372 
373 	if (!boot_params.hdr.type_of_loader ||
374 	    !ramdisk_image || !ramdisk_size)
375 		return;		/* No initrd provided by bootloader */
376 
377 	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
378 }
379 static void __init reserve_initrd(void)
380 {
381 	/* Assume only end is not page aligned */
382 	u64 ramdisk_image = get_ramdisk_image();
383 	u64 ramdisk_size  = get_ramdisk_size();
384 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
385 	u64 mapped_size;
386 
387 	if (!boot_params.hdr.type_of_loader ||
388 	    !ramdisk_image || !ramdisk_size)
389 		return;		/* No initrd provided by bootloader */
390 
391 	initrd_start = 0;
392 
393 	mapped_size = memblock_mem_size(max_pfn_mapped);
394 	if (ramdisk_size >= (mapped_size>>1))
395 		panic("initrd too large to handle, "
396 		       "disabling initrd (%lld needed, %lld available)\n",
397 		       ramdisk_size, mapped_size>>1);
398 
399 	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
400 			ramdisk_end - 1);
401 
402 	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
403 				PFN_DOWN(ramdisk_end))) {
404 		/* All are mapped, easy case */
405 		initrd_start = ramdisk_image + PAGE_OFFSET;
406 		initrd_end = initrd_start + ramdisk_size;
407 		return;
408 	}
409 
410 	relocate_initrd();
411 
412 	memblock_free(ramdisk_image, ramdisk_end - ramdisk_image);
413 }
414 #else
415 static void __init early_reserve_initrd(void)
416 {
417 }
418 static void __init reserve_initrd(void)
419 {
420 }
421 #endif /* CONFIG_BLK_DEV_INITRD */
422 
423 static void __init parse_setup_data(void)
424 {
425 	struct setup_data *data;
426 	u64 pa_data;
427 
428 	pa_data = boot_params.hdr.setup_data;
429 	while (pa_data) {
430 		u32 data_len, map_len;
431 
432 		map_len = max(PAGE_SIZE - (pa_data & ~PAGE_MASK),
433 			      (u64)sizeof(struct setup_data));
434 		data = early_memremap(pa_data, map_len);
435 		data_len = data->len + sizeof(struct setup_data);
436 		if (data_len > map_len) {
437 			early_iounmap(data, map_len);
438 			data = early_memremap(pa_data, data_len);
439 			map_len = data_len;
440 		}
441 
442 		switch (data->type) {
443 		case SETUP_E820_EXT:
444 			parse_e820_ext(data);
445 			break;
446 		case SETUP_DTB:
447 			add_dtb(pa_data);
448 			break;
449 		default:
450 			break;
451 		}
452 		pa_data = data->next;
453 		early_iounmap(data, map_len);
454 	}
455 }
456 
457 static void __init e820_reserve_setup_data(void)
458 {
459 	struct setup_data *data;
460 	u64 pa_data;
461 	int found = 0;
462 
463 	pa_data = boot_params.hdr.setup_data;
464 	while (pa_data) {
465 		data = early_memremap(pa_data, sizeof(*data));
466 		e820_update_range(pa_data, sizeof(*data)+data->len,
467 			 E820_RAM, E820_RESERVED_KERN);
468 		found = 1;
469 		pa_data = data->next;
470 		early_iounmap(data, sizeof(*data));
471 	}
472 	if (!found)
473 		return;
474 
475 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
476 	memcpy(&e820_saved, &e820, sizeof(struct e820map));
477 	printk(KERN_INFO "extended physical RAM map:\n");
478 	e820_print_map("reserve setup_data");
479 }
480 
481 static void __init memblock_x86_reserve_range_setup_data(void)
482 {
483 	struct setup_data *data;
484 	u64 pa_data;
485 
486 	pa_data = boot_params.hdr.setup_data;
487 	while (pa_data) {
488 		data = early_memremap(pa_data, sizeof(*data));
489 		memblock_reserve(pa_data, sizeof(*data) + data->len);
490 		pa_data = data->next;
491 		early_iounmap(data, sizeof(*data));
492 	}
493 }
494 
495 /*
496  * --------- Crashkernel reservation ------------------------------
497  */
498 
499 #ifdef CONFIG_KEXEC
500 
501 /*
502  * Keep the crash kernel below this limit.  On 32 bits earlier kernels
503  * would limit the kernel to the low 512 MiB due to mapping restrictions.
504  */
505 #ifdef CONFIG_X86_32
506 # define CRASH_KERNEL_ADDR_MAX	(512 << 20)
507 #else
508 # define CRASH_KERNEL_ADDR_MAX	MAXMEM
509 #endif
510 
511 static void __init reserve_crashkernel_low(void)
512 {
513 #ifdef CONFIG_X86_64
514 	const unsigned long long alignment = 16<<20;	/* 16M */
515 	unsigned long long low_base = 0, low_size = 0;
516 	unsigned long total_low_mem;
517 	unsigned long long base;
518 	int ret;
519 
520 	total_low_mem = memblock_mem_size(1UL<<(32-PAGE_SHIFT));
521 	ret = parse_crashkernel_low(boot_command_line, total_low_mem,
522 						&low_size, &base);
523 	if (ret != 0 || low_size <= 0)
524 		return;
525 
526 	low_base = memblock_find_in_range(low_size, (1ULL<<32),
527 					low_size, alignment);
528 
529 	if (!low_base) {
530 		pr_info("crashkernel low reservation failed - No suitable area found.\n");
531 
532 		return;
533 	}
534 
535 	memblock_reserve(low_base, low_size);
536 	pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n",
537 			(unsigned long)(low_size >> 20),
538 			(unsigned long)(low_base >> 20),
539 			(unsigned long)(total_low_mem >> 20));
540 	crashk_low_res.start = low_base;
541 	crashk_low_res.end   = low_base + low_size - 1;
542 	insert_resource(&iomem_resource, &crashk_low_res);
543 #endif
544 }
545 
546 static void __init reserve_crashkernel(void)
547 {
548 	const unsigned long long alignment = 16<<20;	/* 16M */
549 	unsigned long long total_mem;
550 	unsigned long long crash_size, crash_base;
551 	int ret;
552 
553 	total_mem = memblock_phys_mem_size();
554 
555 	ret = parse_crashkernel(boot_command_line, total_mem,
556 			&crash_size, &crash_base);
557 	if (ret != 0 || crash_size <= 0)
558 		return;
559 
560 	/* 0 means: find the address automatically */
561 	if (crash_base <= 0) {
562 		/*
563 		 *  kexec want bzImage is below CRASH_KERNEL_ADDR_MAX
564 		 */
565 		crash_base = memblock_find_in_range(alignment,
566 			       CRASH_KERNEL_ADDR_MAX, crash_size, alignment);
567 
568 		if (!crash_base) {
569 			pr_info("crashkernel reservation failed - No suitable area found.\n");
570 			return;
571 		}
572 
573 	} else {
574 		unsigned long long start;
575 
576 		start = memblock_find_in_range(crash_base,
577 				 crash_base + crash_size, crash_size, 1<<20);
578 		if (start != crash_base) {
579 			pr_info("crashkernel reservation failed - memory is in use.\n");
580 			return;
581 		}
582 	}
583 	memblock_reserve(crash_base, crash_size);
584 
585 	printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
586 			"for crashkernel (System RAM: %ldMB)\n",
587 			(unsigned long)(crash_size >> 20),
588 			(unsigned long)(crash_base >> 20),
589 			(unsigned long)(total_mem >> 20));
590 
591 	crashk_res.start = crash_base;
592 	crashk_res.end   = crash_base + crash_size - 1;
593 	insert_resource(&iomem_resource, &crashk_res);
594 
595 	if (crash_base >= (1ULL<<32))
596 		reserve_crashkernel_low();
597 }
598 #else
599 static void __init reserve_crashkernel(void)
600 {
601 }
602 #endif
603 
604 static struct resource standard_io_resources[] = {
605 	{ .name = "dma1", .start = 0x00, .end = 0x1f,
606 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
607 	{ .name = "pic1", .start = 0x20, .end = 0x21,
608 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
609 	{ .name = "timer0", .start = 0x40, .end = 0x43,
610 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
611 	{ .name = "timer1", .start = 0x50, .end = 0x53,
612 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
613 	{ .name = "keyboard", .start = 0x60, .end = 0x60,
614 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
615 	{ .name = "keyboard", .start = 0x64, .end = 0x64,
616 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
617 	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
618 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
619 	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
620 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
621 	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
622 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
623 	{ .name = "fpu", .start = 0xf0, .end = 0xff,
624 		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
625 };
626 
627 void __init reserve_standard_io_resources(void)
628 {
629 	int i;
630 
631 	/* request I/O space for devices used on all i[345]86 PCs */
632 	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
633 		request_resource(&ioport_resource, &standard_io_resources[i]);
634 
635 }
636 
637 static __init void reserve_ibft_region(void)
638 {
639 	unsigned long addr, size = 0;
640 
641 	addr = find_ibft_region(&size);
642 
643 	if (size)
644 		memblock_reserve(addr, size);
645 }
646 
647 static bool __init snb_gfx_workaround_needed(void)
648 {
649 #ifdef CONFIG_PCI
650 	int i;
651 	u16 vendor, devid;
652 	static const __initconst u16 snb_ids[] = {
653 		0x0102,
654 		0x0112,
655 		0x0122,
656 		0x0106,
657 		0x0116,
658 		0x0126,
659 		0x010a,
660 	};
661 
662 	/* Assume no if something weird is going on with PCI */
663 	if (!early_pci_allowed())
664 		return false;
665 
666 	vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
667 	if (vendor != 0x8086)
668 		return false;
669 
670 	devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
671 	for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
672 		if (devid == snb_ids[i])
673 			return true;
674 #endif
675 
676 	return false;
677 }
678 
679 /*
680  * Sandy Bridge graphics has trouble with certain ranges, exclude
681  * them from allocation.
682  */
683 static void __init trim_snb_memory(void)
684 {
685 	static const __initconst unsigned long bad_pages[] = {
686 		0x20050000,
687 		0x20110000,
688 		0x20130000,
689 		0x20138000,
690 		0x40004000,
691 	};
692 	int i;
693 
694 	if (!snb_gfx_workaround_needed())
695 		return;
696 
697 	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
698 
699 	/*
700 	 * Reserve all memory below the 1 MB mark that has not
701 	 * already been reserved.
702 	 */
703 	memblock_reserve(0, 1<<20);
704 
705 	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
706 		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
707 			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
708 			       bad_pages[i]);
709 	}
710 }
711 
712 /*
713  * Here we put platform-specific memory range workarounds, i.e.
714  * memory known to be corrupt or otherwise in need to be reserved on
715  * specific platforms.
716  *
717  * If this gets used more widely it could use a real dispatch mechanism.
718  */
719 static void __init trim_platform_memory_ranges(void)
720 {
721 	trim_snb_memory();
722 }
723 
724 static void __init trim_bios_range(void)
725 {
726 	/*
727 	 * A special case is the first 4Kb of memory;
728 	 * This is a BIOS owned area, not kernel ram, but generally
729 	 * not listed as such in the E820 table.
730 	 *
731 	 * This typically reserves additional memory (64KiB by default)
732 	 * since some BIOSes are known to corrupt low memory.  See the
733 	 * Kconfig help text for X86_RESERVE_LOW.
734 	 */
735 	e820_update_range(0, PAGE_SIZE, E820_RAM, E820_RESERVED);
736 
737 	/*
738 	 * special case: Some BIOSen report the PC BIOS
739 	 * area (640->1Mb) as ram even though it is not.
740 	 * take them out.
741 	 */
742 	e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1);
743 
744 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
745 }
746 
747 /* called before trim_bios_range() to spare extra sanitize */
748 static void __init e820_add_kernel_range(void)
749 {
750 	u64 start = __pa_symbol(_text);
751 	u64 size = __pa_symbol(_end) - start;
752 
753 	/*
754 	 * Complain if .text .data and .bss are not marked as E820_RAM and
755 	 * attempt to fix it by adding the range. We may have a confused BIOS,
756 	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
757 	 * exclude kernel range. If we really are running on top non-RAM,
758 	 * we will crash later anyways.
759 	 */
760 	if (e820_all_mapped(start, start + size, E820_RAM))
761 		return;
762 
763 	pr_warn(".text .data .bss are not marked as E820_RAM!\n");
764 	e820_remove_range(start, size, E820_RAM, 0);
765 	e820_add_region(start, size, E820_RAM);
766 }
767 
768 static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10;
769 
770 static int __init parse_reservelow(char *p)
771 {
772 	unsigned long long size;
773 
774 	if (!p)
775 		return -EINVAL;
776 
777 	size = memparse(p, &p);
778 
779 	if (size < 4096)
780 		size = 4096;
781 
782 	if (size > 640*1024)
783 		size = 640*1024;
784 
785 	reserve_low = size;
786 
787 	return 0;
788 }
789 
790 early_param("reservelow", parse_reservelow);
791 
792 static void __init trim_low_memory_range(void)
793 {
794 	memblock_reserve(0, ALIGN(reserve_low, PAGE_SIZE));
795 }
796 
797 /*
798  * Determine if we were loaded by an EFI loader.  If so, then we have also been
799  * passed the efi memmap, systab, etc., so we should use these data structures
800  * for initialization.  Note, the efi init code path is determined by the
801  * global efi_enabled. This allows the same kernel image to be used on existing
802  * systems (with a traditional BIOS) as well as on EFI systems.
803  */
804 /*
805  * setup_arch - architecture-specific boot-time initializations
806  *
807  * Note: On x86_64, fixmaps are ready for use even before this is called.
808  */
809 
810 void __init setup_arch(char **cmdline_p)
811 {
812 	memblock_reserve(__pa_symbol(_text),
813 			 (unsigned long)__bss_stop - (unsigned long)_text);
814 
815 	early_reserve_initrd();
816 
817 	/*
818 	 * At this point everything still needed from the boot loader
819 	 * or BIOS or kernel text should be early reserved or marked not
820 	 * RAM in e820. All other memory is free game.
821 	 */
822 
823 #ifdef CONFIG_X86_32
824 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
825 	visws_early_detect();
826 
827 	/*
828 	 * copy kernel address range established so far and switch
829 	 * to the proper swapper page table
830 	 */
831 	clone_pgd_range(swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
832 			initial_page_table + KERNEL_PGD_BOUNDARY,
833 			KERNEL_PGD_PTRS);
834 
835 	load_cr3(swapper_pg_dir);
836 	__flush_tlb_all();
837 #else
838 	printk(KERN_INFO "Command line: %s\n", boot_command_line);
839 #endif
840 
841 	/*
842 	 * If we have OLPC OFW, we might end up relocating the fixmap due to
843 	 * reserve_top(), so do this before touching the ioremap area.
844 	 */
845 	olpc_ofw_detect();
846 
847 	early_trap_init();
848 	early_cpu_init();
849 	early_ioremap_init();
850 
851 	setup_olpc_ofw_pgd();
852 
853 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
854 	screen_info = boot_params.screen_info;
855 	edid_info = boot_params.edid_info;
856 #ifdef CONFIG_X86_32
857 	apm_info.bios = boot_params.apm_bios_info;
858 	ist_info = boot_params.ist_info;
859 	if (boot_params.sys_desc_table.length != 0) {
860 		machine_id = boot_params.sys_desc_table.table[0];
861 		machine_submodel_id = boot_params.sys_desc_table.table[1];
862 		BIOS_revision = boot_params.sys_desc_table.table[2];
863 	}
864 #endif
865 	saved_video_mode = boot_params.hdr.vid_mode;
866 	bootloader_type = boot_params.hdr.type_of_loader;
867 	if ((bootloader_type >> 4) == 0xe) {
868 		bootloader_type &= 0xf;
869 		bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
870 	}
871 	bootloader_version  = bootloader_type & 0xf;
872 	bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
873 
874 #ifdef CONFIG_BLK_DEV_RAM
875 	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
876 	rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
877 	rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
878 #endif
879 #ifdef CONFIG_EFI
880 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
881 		     "EL32", 4)) {
882 		set_bit(EFI_BOOT, &x86_efi_facility);
883 	} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
884 		     "EL64", 4)) {
885 		set_bit(EFI_BOOT, &x86_efi_facility);
886 		set_bit(EFI_64BIT, &x86_efi_facility);
887 	}
888 
889 	if (efi_enabled(EFI_BOOT))
890 		efi_memblock_x86_reserve_range();
891 #endif
892 
893 	x86_init.oem.arch_setup();
894 
895 	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
896 	setup_memory_map();
897 	parse_setup_data();
898 	/* update the e820_saved too */
899 	e820_reserve_setup_data();
900 
901 	copy_edd();
902 
903 	if (!boot_params.hdr.root_flags)
904 		root_mountflags &= ~MS_RDONLY;
905 	init_mm.start_code = (unsigned long) _text;
906 	init_mm.end_code = (unsigned long) _etext;
907 	init_mm.end_data = (unsigned long) _edata;
908 	init_mm.brk = _brk_end;
909 
910 	code_resource.start = __pa_symbol(_text);
911 	code_resource.end = __pa_symbol(_etext)-1;
912 	data_resource.start = __pa_symbol(_etext);
913 	data_resource.end = __pa_symbol(_edata)-1;
914 	bss_resource.start = __pa_symbol(__bss_start);
915 	bss_resource.end = __pa_symbol(__bss_stop)-1;
916 
917 #ifdef CONFIG_CMDLINE_BOOL
918 #ifdef CONFIG_CMDLINE_OVERRIDE
919 	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
920 #else
921 	if (builtin_cmdline[0]) {
922 		/* append boot loader cmdline to builtin */
923 		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
924 		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
925 		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
926 	}
927 #endif
928 #endif
929 
930 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
931 	*cmdline_p = command_line;
932 
933 	/*
934 	 * x86_configure_nx() is called before parse_early_param() to detect
935 	 * whether hardware doesn't support NX (so that the early EHCI debug
936 	 * console setup can safely call set_fixmap()). It may then be called
937 	 * again from within noexec_setup() during parsing early parameters
938 	 * to honor the respective command line option.
939 	 */
940 	x86_configure_nx();
941 
942 	parse_early_param();
943 
944 	x86_report_nx();
945 
946 	/* after early param, so could get panic from serial */
947 	memblock_x86_reserve_range_setup_data();
948 
949 	if (acpi_mps_check()) {
950 #ifdef CONFIG_X86_LOCAL_APIC
951 		disable_apic = 1;
952 #endif
953 		setup_clear_cpu_cap(X86_FEATURE_APIC);
954 	}
955 
956 #ifdef CONFIG_PCI
957 	if (pci_early_dump_regs)
958 		early_dump_pci_devices();
959 #endif
960 
961 	finish_e820_parsing();
962 
963 	if (efi_enabled(EFI_BOOT))
964 		efi_init();
965 
966 	dmi_scan_machine();
967 
968 	/*
969 	 * VMware detection requires dmi to be available, so this
970 	 * needs to be done after dmi_scan_machine, for the BP.
971 	 */
972 	init_hypervisor_platform();
973 
974 	x86_init.resources.probe_roms();
975 
976 	/* after parse_early_param, so could debug it */
977 	insert_resource(&iomem_resource, &code_resource);
978 	insert_resource(&iomem_resource, &data_resource);
979 	insert_resource(&iomem_resource, &bss_resource);
980 
981 	e820_add_kernel_range();
982 	trim_bios_range();
983 #ifdef CONFIG_X86_32
984 	if (ppro_with_ram_bug()) {
985 		e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
986 				  E820_RESERVED);
987 		sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
988 		printk(KERN_INFO "fixed physical RAM map:\n");
989 		e820_print_map("bad_ppro");
990 	}
991 #else
992 	early_gart_iommu_check();
993 #endif
994 
995 	/*
996 	 * partially used pages are not usable - thus
997 	 * we are rounding upwards:
998 	 */
999 	max_pfn = e820_end_of_ram_pfn();
1000 
1001 	/* update e820 for memory not covered by WB MTRRs */
1002 	mtrr_bp_init();
1003 	if (mtrr_trim_uncached_memory(max_pfn))
1004 		max_pfn = e820_end_of_ram_pfn();
1005 
1006 #ifdef CONFIG_X86_32
1007 	/* max_low_pfn get updated here */
1008 	find_low_pfn_range();
1009 #else
1010 	num_physpages = max_pfn;
1011 
1012 	check_x2apic();
1013 
1014 	/* How many end-of-memory variables you have, grandma! */
1015 	/* need this before calling reserve_initrd */
1016 	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
1017 		max_low_pfn = e820_end_of_low_ram_pfn();
1018 	else
1019 		max_low_pfn = max_pfn;
1020 
1021 	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
1022 #endif
1023 
1024 	/*
1025 	 * Find and reserve possible boot-time SMP configuration:
1026 	 */
1027 	find_smp_config();
1028 
1029 	reserve_ibft_region();
1030 
1031 	early_alloc_pgt_buf();
1032 
1033 	/*
1034 	 * Need to conclude brk, before memblock_x86_fill()
1035 	 *  it could use memblock_find_in_range, could overlap with
1036 	 *  brk area.
1037 	 */
1038 	reserve_brk();
1039 
1040 	cleanup_highmap();
1041 
1042 	memblock.current_limit = ISA_END_ADDRESS;
1043 	memblock_x86_fill();
1044 
1045 	/*
1046 	 * The EFI specification says that boot service code won't be called
1047 	 * after ExitBootServices(). This is, in fact, a lie.
1048 	 */
1049 	if (efi_enabled(EFI_MEMMAP))
1050 		efi_reserve_boot_services();
1051 
1052 	/* preallocate 4k for mptable mpc */
1053 	early_reserve_e820_mpc_new();
1054 
1055 #ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1056 	setup_bios_corruption_check();
1057 #endif
1058 
1059 #ifdef CONFIG_X86_32
1060 	printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1061 			(max_pfn_mapped<<PAGE_SHIFT) - 1);
1062 #endif
1063 
1064 	reserve_real_mode();
1065 
1066 	trim_platform_memory_ranges();
1067 	trim_low_memory_range();
1068 
1069 	init_mem_mapping();
1070 
1071 	early_trap_pf_init();
1072 
1073 	setup_real_mode();
1074 
1075 	memblock.current_limit = get_max_mapped();
1076 	dma_contiguous_reserve(0);
1077 
1078 	/*
1079 	 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1080 	 */
1081 
1082 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1083 	if (init_ohci1394_dma_early)
1084 		init_ohci1394_dma_on_all_controllers();
1085 #endif
1086 	/* Allocate bigger log buffer */
1087 	setup_log_buf(1);
1088 
1089 	reserve_initrd();
1090 
1091 #if defined(CONFIG_ACPI) && defined(CONFIG_BLK_DEV_INITRD)
1092 	acpi_initrd_override((void *)initrd_start, initrd_end - initrd_start);
1093 #endif
1094 
1095 	reserve_crashkernel();
1096 
1097 	vsmp_init();
1098 
1099 	io_delay_init();
1100 
1101 	/*
1102 	 * Parse the ACPI tables for possible boot-time SMP configuration.
1103 	 */
1104 	acpi_boot_table_init();
1105 
1106 	early_acpi_boot_init();
1107 
1108 	initmem_init();
1109 	memblock_find_dma_reserve();
1110 
1111 #ifdef CONFIG_KVM_GUEST
1112 	kvmclock_init();
1113 #endif
1114 
1115 	x86_init.paging.pagetable_init();
1116 
1117 	if (boot_cpu_data.cpuid_level >= 0) {
1118 		/* A CPU has %cr4 if and only if it has CPUID */
1119 		mmu_cr4_features = read_cr4();
1120 		if (trampoline_cr4_features)
1121 			*trampoline_cr4_features = mmu_cr4_features;
1122 	}
1123 
1124 #ifdef CONFIG_X86_32
1125 	/* sync back kernel address range */
1126 	clone_pgd_range(initial_page_table + KERNEL_PGD_BOUNDARY,
1127 			swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
1128 			KERNEL_PGD_PTRS);
1129 #endif
1130 
1131 	tboot_probe();
1132 
1133 #ifdef CONFIG_X86_64
1134 	map_vsyscall();
1135 #endif
1136 
1137 	generic_apic_probe();
1138 
1139 	early_quirks();
1140 
1141 	/*
1142 	 * Read APIC and some other early information from ACPI tables.
1143 	 */
1144 	acpi_boot_init();
1145 	sfi_init();
1146 	x86_dtb_init();
1147 
1148 	/*
1149 	 * get boot-time SMP configuration:
1150 	 */
1151 	if (smp_found_config)
1152 		get_smp_config();
1153 
1154 	prefill_possible_map();
1155 
1156 	init_cpu_to_node();
1157 
1158 	init_apic_mappings();
1159 	if (x86_io_apic_ops.init)
1160 		x86_io_apic_ops.init();
1161 
1162 	kvm_guest_init();
1163 
1164 	e820_reserve_resources();
1165 	e820_mark_nosave_regions(max_low_pfn);
1166 
1167 	x86_init.resources.reserve_resources();
1168 
1169 	e820_setup_gap();
1170 
1171 #ifdef CONFIG_VT
1172 #if defined(CONFIG_VGA_CONSOLE)
1173 	if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1174 		conswitchp = &vga_con;
1175 #elif defined(CONFIG_DUMMY_CONSOLE)
1176 	conswitchp = &dummy_con;
1177 #endif
1178 #endif
1179 	x86_init.oem.banner();
1180 
1181 	x86_init.timers.wallclock_init();
1182 
1183 	mcheck_init();
1184 
1185 	arch_init_ideal_nops();
1186 
1187 	register_refined_jiffies(CLOCK_TICK_RATE);
1188 
1189 #ifdef CONFIG_EFI
1190 	/* Once setup is done above, unmap the EFI memory map on
1191 	 * mismatched firmware/kernel archtectures since there is no
1192 	 * support for runtime services.
1193 	 */
1194 	if (efi_enabled(EFI_BOOT) && !efi_is_native()) {
1195 		pr_info("efi: Setup done, disabling due to 32/64-bit mismatch\n");
1196 		efi_unmap_memmap();
1197 	}
1198 #endif
1199 }
1200 
1201 #ifdef CONFIG_X86_32
1202 
1203 static struct resource video_ram_resource = {
1204 	.name	= "Video RAM area",
1205 	.start	= 0xa0000,
1206 	.end	= 0xbffff,
1207 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1208 };
1209 
1210 void __init i386_reserve_resources(void)
1211 {
1212 	request_resource(&iomem_resource, &video_ram_resource);
1213 	reserve_standard_io_resources();
1214 }
1215 
1216 #endif /* CONFIG_X86_32 */
1217