xref: /linux/arch/x86/kernel/setup.c (revision 110e6f26af80dfd90b6e5c645b1aed7228aa580d)
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/io_apic.h>
86 #include <asm/ist.h>
87 #include <asm/setup_arch.h>
88 #include <asm/bios_ebda.h>
89 #include <asm/cacheflush.h>
90 #include <asm/processor.h>
91 #include <asm/bugs.h>
92 #include <asm/kasan.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 #include <asm/microcode.h>
115 #include <asm/mmu_context.h>
116 
117 /*
118  * max_low_pfn_mapped: highest direct mapped pfn under 4GB
119  * max_pfn_mapped:     highest direct mapped pfn over 4GB
120  *
121  * The direct mapping only covers E820_RAM regions, so the ranges and gaps are
122  * represented by pfn_mapped
123  */
124 unsigned long max_low_pfn_mapped;
125 unsigned long max_pfn_mapped;
126 
127 #ifdef CONFIG_DMI
128 RESERVE_BRK(dmi_alloc, 65536);
129 #endif
130 
131 
132 static __initdata unsigned long _brk_start = (unsigned long)__brk_base;
133 unsigned long _brk_end = (unsigned long)__brk_base;
134 
135 #ifdef CONFIG_X86_64
136 int default_cpu_present_to_apicid(int mps_cpu)
137 {
138 	return __default_cpu_present_to_apicid(mps_cpu);
139 }
140 
141 int default_check_phys_apicid_present(int phys_apicid)
142 {
143 	return __default_check_phys_apicid_present(phys_apicid);
144 }
145 #endif
146 
147 struct boot_params boot_params;
148 
149 #ifdef CONFIG_X86_32
150 /* cpu data as detected by the assembly code in head.S */
151 struct cpuinfo_x86 new_cpu_data = {
152 	.wp_works_ok = -1,
153 };
154 /* common cpu data for all cpus */
155 struct cpuinfo_x86 boot_cpu_data __read_mostly = {
156 	.wp_works_ok = -1,
157 };
158 EXPORT_SYMBOL(boot_cpu_data);
159 
160 unsigned int def_to_bigsmp;
161 
162 /* for MCA, but anyone else can use it if they want */
163 unsigned int machine_id;
164 unsigned int machine_submodel_id;
165 unsigned int BIOS_revision;
166 
167 struct apm_info apm_info;
168 EXPORT_SYMBOL(apm_info);
169 
170 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
171 	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
172 struct ist_info ist_info;
173 EXPORT_SYMBOL(ist_info);
174 #else
175 struct ist_info ist_info;
176 #endif
177 
178 #else
179 struct cpuinfo_x86 boot_cpu_data __read_mostly = {
180 	.x86_phys_bits = MAX_PHYSMEM_BITS,
181 };
182 EXPORT_SYMBOL(boot_cpu_data);
183 #endif
184 
185 
186 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
187 __visible unsigned long mmu_cr4_features;
188 #else
189 __visible unsigned long mmu_cr4_features = X86_CR4_PAE;
190 #endif
191 
192 /* Boot loader ID and version as integers, for the benefit of proc_dointvec */
193 int bootloader_type, bootloader_version;
194 
195 /*
196  * Setup options
197  */
198 struct screen_info screen_info;
199 EXPORT_SYMBOL(screen_info);
200 struct edid_info edid_info;
201 EXPORT_SYMBOL_GPL(edid_info);
202 
203 extern int root_mountflags;
204 
205 unsigned long saved_video_mode;
206 
207 #define RAMDISK_IMAGE_START_MASK	0x07FF
208 #define RAMDISK_PROMPT_FLAG		0x8000
209 #define RAMDISK_LOAD_FLAG		0x4000
210 
211 static char __initdata command_line[COMMAND_LINE_SIZE];
212 #ifdef CONFIG_CMDLINE_BOOL
213 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
214 #endif
215 
216 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
217 struct edd edd;
218 #ifdef CONFIG_EDD_MODULE
219 EXPORT_SYMBOL(edd);
220 #endif
221 /**
222  * copy_edd() - Copy the BIOS EDD information
223  *              from boot_params into a safe place.
224  *
225  */
226 static inline void __init copy_edd(void)
227 {
228      memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
229 	    sizeof(edd.mbr_signature));
230      memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
231      edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
232      edd.edd_info_nr = boot_params.eddbuf_entries;
233 }
234 #else
235 static inline void __init copy_edd(void)
236 {
237 }
238 #endif
239 
240 void * __init extend_brk(size_t size, size_t align)
241 {
242 	size_t mask = align - 1;
243 	void *ret;
244 
245 	BUG_ON(_brk_start == 0);
246 	BUG_ON(align & mask);
247 
248 	_brk_end = (_brk_end + mask) & ~mask;
249 	BUG_ON((char *)(_brk_end + size) > __brk_limit);
250 
251 	ret = (void *)_brk_end;
252 	_brk_end += size;
253 
254 	memset(ret, 0, size);
255 
256 	return ret;
257 }
258 
259 #ifdef CONFIG_X86_32
260 static void __init cleanup_highmap(void)
261 {
262 }
263 #endif
264 
265 static void __init reserve_brk(void)
266 {
267 	if (_brk_end > _brk_start)
268 		memblock_reserve(__pa_symbol(_brk_start),
269 				 _brk_end - _brk_start);
270 
271 	/* Mark brk area as locked down and no longer taking any
272 	   new allocations */
273 	_brk_start = 0;
274 }
275 
276 u64 relocated_ramdisk;
277 
278 #ifdef CONFIG_BLK_DEV_INITRD
279 
280 static u64 __init get_ramdisk_image(void)
281 {
282 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
283 
284 	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
285 
286 	return ramdisk_image;
287 }
288 static u64 __init get_ramdisk_size(void)
289 {
290 	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
291 
292 	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
293 
294 	return ramdisk_size;
295 }
296 
297 static void __init relocate_initrd(void)
298 {
299 	/* Assume only end is not page aligned */
300 	u64 ramdisk_image = get_ramdisk_image();
301 	u64 ramdisk_size  = get_ramdisk_size();
302 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
303 
304 	/* We need to move the initrd down into directly mapped mem */
305 	relocated_ramdisk = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
306 						   area_size, PAGE_SIZE);
307 
308 	if (!relocated_ramdisk)
309 		panic("Cannot find place for new RAMDISK of size %lld\n",
310 		      ramdisk_size);
311 
312 	/* Note: this includes all the mem currently occupied by
313 	   the initrd, we rely on that fact to keep the data intact. */
314 	memblock_reserve(relocated_ramdisk, area_size);
315 	initrd_start = relocated_ramdisk + PAGE_OFFSET;
316 	initrd_end   = initrd_start + ramdisk_size;
317 	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
318 	       relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
319 
320 	copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
321 
322 	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
323 		" [mem %#010llx-%#010llx]\n",
324 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
325 		relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
326 }
327 
328 static void __init early_reserve_initrd(void)
329 {
330 	/* Assume only end is not page aligned */
331 	u64 ramdisk_image = get_ramdisk_image();
332 	u64 ramdisk_size  = get_ramdisk_size();
333 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
334 
335 	if (!boot_params.hdr.type_of_loader ||
336 	    !ramdisk_image || !ramdisk_size)
337 		return;		/* No initrd provided by bootloader */
338 
339 	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
340 }
341 static void __init reserve_initrd(void)
342 {
343 	/* Assume only end is not page aligned */
344 	u64 ramdisk_image = get_ramdisk_image();
345 	u64 ramdisk_size  = get_ramdisk_size();
346 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
347 	u64 mapped_size;
348 
349 	if (!boot_params.hdr.type_of_loader ||
350 	    !ramdisk_image || !ramdisk_size)
351 		return;		/* No initrd provided by bootloader */
352 
353 	initrd_start = 0;
354 
355 	mapped_size = memblock_mem_size(max_pfn_mapped);
356 	if (ramdisk_size >= (mapped_size>>1))
357 		panic("initrd too large to handle, "
358 		       "disabling initrd (%lld needed, %lld available)\n",
359 		       ramdisk_size, mapped_size>>1);
360 
361 	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
362 			ramdisk_end - 1);
363 
364 	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
365 				PFN_DOWN(ramdisk_end))) {
366 		/* All are mapped, easy case */
367 		initrd_start = ramdisk_image + PAGE_OFFSET;
368 		initrd_end = initrd_start + ramdisk_size;
369 		return;
370 	}
371 
372 	relocate_initrd();
373 
374 	memblock_free(ramdisk_image, ramdisk_end - ramdisk_image);
375 }
376 #else
377 static void __init early_reserve_initrd(void)
378 {
379 }
380 static void __init reserve_initrd(void)
381 {
382 }
383 #endif /* CONFIG_BLK_DEV_INITRD */
384 
385 static void __init parse_setup_data(void)
386 {
387 	struct setup_data *data;
388 	u64 pa_data, pa_next;
389 
390 	pa_data = boot_params.hdr.setup_data;
391 	while (pa_data) {
392 		u32 data_len, data_type;
393 
394 		data = early_memremap(pa_data, sizeof(*data));
395 		data_len = data->len + sizeof(struct setup_data);
396 		data_type = data->type;
397 		pa_next = data->next;
398 		early_memunmap(data, sizeof(*data));
399 
400 		switch (data_type) {
401 		case SETUP_E820_EXT:
402 			parse_e820_ext(pa_data, data_len);
403 			break;
404 		case SETUP_DTB:
405 			add_dtb(pa_data);
406 			break;
407 		case SETUP_EFI:
408 			parse_efi_setup(pa_data, data_len);
409 			break;
410 		default:
411 			break;
412 		}
413 		pa_data = pa_next;
414 	}
415 }
416 
417 static void __init e820_reserve_setup_data(void)
418 {
419 	struct setup_data *data;
420 	u64 pa_data;
421 
422 	pa_data = boot_params.hdr.setup_data;
423 	if (!pa_data)
424 		return;
425 
426 	while (pa_data) {
427 		data = early_memremap(pa_data, sizeof(*data));
428 		e820_update_range(pa_data, sizeof(*data)+data->len,
429 			 E820_RAM, E820_RESERVED_KERN);
430 		pa_data = data->next;
431 		early_memunmap(data, sizeof(*data));
432 	}
433 
434 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
435 	memcpy(&e820_saved, &e820, sizeof(struct e820map));
436 	printk(KERN_INFO "extended physical RAM map:\n");
437 	e820_print_map("reserve setup_data");
438 }
439 
440 static void __init memblock_x86_reserve_range_setup_data(void)
441 {
442 	struct setup_data *data;
443 	u64 pa_data;
444 
445 	pa_data = boot_params.hdr.setup_data;
446 	while (pa_data) {
447 		data = early_memremap(pa_data, sizeof(*data));
448 		memblock_reserve(pa_data, sizeof(*data) + data->len);
449 		pa_data = data->next;
450 		early_memunmap(data, sizeof(*data));
451 	}
452 }
453 
454 /*
455  * --------- Crashkernel reservation ------------------------------
456  */
457 
458 #ifdef CONFIG_KEXEC_CORE
459 
460 /* 16M alignment for crash kernel regions */
461 #define CRASH_ALIGN		(16 << 20)
462 
463 /*
464  * Keep the crash kernel below this limit.  On 32 bits earlier kernels
465  * would limit the kernel to the low 512 MiB due to mapping restrictions.
466  * On 64bit, old kexec-tools need to under 896MiB.
467  */
468 #ifdef CONFIG_X86_32
469 # define CRASH_ADDR_LOW_MAX	(512 << 20)
470 # define CRASH_ADDR_HIGH_MAX	(512 << 20)
471 #else
472 # define CRASH_ADDR_LOW_MAX	(896UL << 20)
473 # define CRASH_ADDR_HIGH_MAX	MAXMEM
474 #endif
475 
476 static int __init reserve_crashkernel_low(void)
477 {
478 #ifdef CONFIG_X86_64
479 	unsigned long long base, low_base = 0, low_size = 0;
480 	unsigned long total_low_mem;
481 	int ret;
482 
483 	total_low_mem = memblock_mem_size(1UL << (32 - PAGE_SHIFT));
484 
485 	/* crashkernel=Y,low */
486 	ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, &base);
487 	if (ret) {
488 		/*
489 		 * two parts from lib/swiotlb.c:
490 		 * -swiotlb size: user-specified with swiotlb= or default.
491 		 *
492 		 * -swiotlb overflow buffer: now hardcoded to 32k. We round it
493 		 * to 8M for other buffers that may need to stay low too. Also
494 		 * make sure we allocate enough extra low memory so that we
495 		 * don't run out of DMA buffers for 32-bit devices.
496 		 */
497 		low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20);
498 	} else {
499 		/* passed with crashkernel=0,low ? */
500 		if (!low_size)
501 			return 0;
502 	}
503 
504 	low_base = memblock_find_in_range(low_size, 1ULL << 32, low_size, CRASH_ALIGN);
505 	if (!low_base) {
506 		pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
507 		       (unsigned long)(low_size >> 20));
508 		return -ENOMEM;
509 	}
510 
511 	ret = memblock_reserve(low_base, low_size);
512 	if (ret) {
513 		pr_err("%s: Error reserving crashkernel low memblock.\n", __func__);
514 		return ret;
515 	}
516 
517 	pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n",
518 		(unsigned long)(low_size >> 20),
519 		(unsigned long)(low_base >> 20),
520 		(unsigned long)(total_low_mem >> 20));
521 
522 	crashk_low_res.start = low_base;
523 	crashk_low_res.end   = low_base + low_size - 1;
524 	insert_resource(&iomem_resource, &crashk_low_res);
525 #endif
526 	return 0;
527 }
528 
529 static void __init reserve_crashkernel(void)
530 {
531 	unsigned long long crash_size, crash_base, total_mem;
532 	bool high = false;
533 	int ret;
534 
535 	total_mem = memblock_phys_mem_size();
536 
537 	/* crashkernel=XM */
538 	ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base);
539 	if (ret != 0 || crash_size <= 0) {
540 		/* crashkernel=X,high */
541 		ret = parse_crashkernel_high(boot_command_line, total_mem,
542 					     &crash_size, &crash_base);
543 		if (ret != 0 || crash_size <= 0)
544 			return;
545 		high = true;
546 	}
547 
548 	/* 0 means: find the address automatically */
549 	if (crash_base <= 0) {
550 		/*
551 		 *  kexec want bzImage is below CRASH_KERNEL_ADDR_MAX
552 		 */
553 		crash_base = memblock_find_in_range(CRASH_ALIGN,
554 						    high ? CRASH_ADDR_HIGH_MAX
555 							 : CRASH_ADDR_LOW_MAX,
556 						    crash_size, CRASH_ALIGN);
557 		if (!crash_base) {
558 			pr_info("crashkernel reservation failed - No suitable area found.\n");
559 			return;
560 		}
561 
562 	} else {
563 		unsigned long long start;
564 
565 		start = memblock_find_in_range(crash_base,
566 					       crash_base + crash_size,
567 					       crash_size, 1 << 20);
568 		if (start != crash_base) {
569 			pr_info("crashkernel reservation failed - memory is in use.\n");
570 			return;
571 		}
572 	}
573 	ret = memblock_reserve(crash_base, crash_size);
574 	if (ret) {
575 		pr_err("%s: Error reserving crashkernel memblock.\n", __func__);
576 		return;
577 	}
578 
579 	if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) {
580 		memblock_free(crash_base, crash_size);
581 		return;
582 	}
583 
584 	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
585 		(unsigned long)(crash_size >> 20),
586 		(unsigned long)(crash_base >> 20),
587 		(unsigned long)(total_mem >> 20));
588 
589 	crashk_res.start = crash_base;
590 	crashk_res.end   = crash_base + crash_size - 1;
591 	insert_resource(&iomem_resource, &crashk_res);
592 }
593 #else
594 static void __init reserve_crashkernel(void)
595 {
596 }
597 #endif
598 
599 static struct resource standard_io_resources[] = {
600 	{ .name = "dma1", .start = 0x00, .end = 0x1f,
601 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
602 	{ .name = "pic1", .start = 0x20, .end = 0x21,
603 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
604 	{ .name = "timer0", .start = 0x40, .end = 0x43,
605 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
606 	{ .name = "timer1", .start = 0x50, .end = 0x53,
607 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
608 	{ .name = "keyboard", .start = 0x60, .end = 0x60,
609 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
610 	{ .name = "keyboard", .start = 0x64, .end = 0x64,
611 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
612 	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
613 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
614 	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
615 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
616 	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
617 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
618 	{ .name = "fpu", .start = 0xf0, .end = 0xff,
619 		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
620 };
621 
622 void __init reserve_standard_io_resources(void)
623 {
624 	int i;
625 
626 	/* request I/O space for devices used on all i[345]86 PCs */
627 	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
628 		request_resource(&ioport_resource, &standard_io_resources[i]);
629 
630 }
631 
632 static __init void reserve_ibft_region(void)
633 {
634 	unsigned long addr, size = 0;
635 
636 	addr = find_ibft_region(&size);
637 
638 	if (size)
639 		memblock_reserve(addr, size);
640 }
641 
642 static bool __init snb_gfx_workaround_needed(void)
643 {
644 #ifdef CONFIG_PCI
645 	int i;
646 	u16 vendor, devid;
647 	static const __initconst u16 snb_ids[] = {
648 		0x0102,
649 		0x0112,
650 		0x0122,
651 		0x0106,
652 		0x0116,
653 		0x0126,
654 		0x010a,
655 	};
656 
657 	/* Assume no if something weird is going on with PCI */
658 	if (!early_pci_allowed())
659 		return false;
660 
661 	vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
662 	if (vendor != 0x8086)
663 		return false;
664 
665 	devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
666 	for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
667 		if (devid == snb_ids[i])
668 			return true;
669 #endif
670 
671 	return false;
672 }
673 
674 /*
675  * Sandy Bridge graphics has trouble with certain ranges, exclude
676  * them from allocation.
677  */
678 static void __init trim_snb_memory(void)
679 {
680 	static const __initconst unsigned long bad_pages[] = {
681 		0x20050000,
682 		0x20110000,
683 		0x20130000,
684 		0x20138000,
685 		0x40004000,
686 	};
687 	int i;
688 
689 	if (!snb_gfx_workaround_needed())
690 		return;
691 
692 	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
693 
694 	/*
695 	 * Reserve all memory below the 1 MB mark that has not
696 	 * already been reserved.
697 	 */
698 	memblock_reserve(0, 1<<20);
699 
700 	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
701 		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
702 			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
703 			       bad_pages[i]);
704 	}
705 }
706 
707 /*
708  * Here we put platform-specific memory range workarounds, i.e.
709  * memory known to be corrupt or otherwise in need to be reserved on
710  * specific platforms.
711  *
712  * If this gets used more widely it could use a real dispatch mechanism.
713  */
714 static void __init trim_platform_memory_ranges(void)
715 {
716 	trim_snb_memory();
717 }
718 
719 static void __init trim_bios_range(void)
720 {
721 	/*
722 	 * A special case is the first 4Kb of memory;
723 	 * This is a BIOS owned area, not kernel ram, but generally
724 	 * not listed as such in the E820 table.
725 	 *
726 	 * This typically reserves additional memory (64KiB by default)
727 	 * since some BIOSes are known to corrupt low memory.  See the
728 	 * Kconfig help text for X86_RESERVE_LOW.
729 	 */
730 	e820_update_range(0, PAGE_SIZE, E820_RAM, E820_RESERVED);
731 
732 	/*
733 	 * special case: Some BIOSen report the PC BIOS
734 	 * area (640->1Mb) as ram even though it is not.
735 	 * take them out.
736 	 */
737 	e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1);
738 
739 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
740 }
741 
742 /* called before trim_bios_range() to spare extra sanitize */
743 static void __init e820_add_kernel_range(void)
744 {
745 	u64 start = __pa_symbol(_text);
746 	u64 size = __pa_symbol(_end) - start;
747 
748 	/*
749 	 * Complain if .text .data and .bss are not marked as E820_RAM and
750 	 * attempt to fix it by adding the range. We may have a confused BIOS,
751 	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
752 	 * exclude kernel range. If we really are running on top non-RAM,
753 	 * we will crash later anyways.
754 	 */
755 	if (e820_all_mapped(start, start + size, E820_RAM))
756 		return;
757 
758 	pr_warn(".text .data .bss are not marked as E820_RAM!\n");
759 	e820_remove_range(start, size, E820_RAM, 0);
760 	e820_add_region(start, size, E820_RAM);
761 }
762 
763 static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10;
764 
765 static int __init parse_reservelow(char *p)
766 {
767 	unsigned long long size;
768 
769 	if (!p)
770 		return -EINVAL;
771 
772 	size = memparse(p, &p);
773 
774 	if (size < 4096)
775 		size = 4096;
776 
777 	if (size > 640*1024)
778 		size = 640*1024;
779 
780 	reserve_low = size;
781 
782 	return 0;
783 }
784 
785 early_param("reservelow", parse_reservelow);
786 
787 static void __init trim_low_memory_range(void)
788 {
789 	memblock_reserve(0, ALIGN(reserve_low, PAGE_SIZE));
790 }
791 
792 /*
793  * Dump out kernel offset information on panic.
794  */
795 static int
796 dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
797 {
798 	if (kaslr_enabled()) {
799 		pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
800 			 kaslr_offset(),
801 			 __START_KERNEL,
802 			 __START_KERNEL_map,
803 			 MODULES_VADDR-1);
804 	} else {
805 		pr_emerg("Kernel Offset: disabled\n");
806 	}
807 
808 	return 0;
809 }
810 
811 /*
812  * Determine if we were loaded by an EFI loader.  If so, then we have also been
813  * passed the efi memmap, systab, etc., so we should use these data structures
814  * for initialization.  Note, the efi init code path is determined by the
815  * global efi_enabled. This allows the same kernel image to be used on existing
816  * systems (with a traditional BIOS) as well as on EFI systems.
817  */
818 /*
819  * setup_arch - architecture-specific boot-time initializations
820  *
821  * Note: On x86_64, fixmaps are ready for use even before this is called.
822  */
823 
824 void __init setup_arch(char **cmdline_p)
825 {
826 	memblock_reserve(__pa_symbol(_text),
827 			 (unsigned long)__bss_stop - (unsigned long)_text);
828 
829 	early_reserve_initrd();
830 
831 	/*
832 	 * At this point everything still needed from the boot loader
833 	 * or BIOS or kernel text should be early reserved or marked not
834 	 * RAM in e820. All other memory is free game.
835 	 */
836 
837 #ifdef CONFIG_X86_32
838 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
839 
840 	/*
841 	 * copy kernel address range established so far and switch
842 	 * to the proper swapper page table
843 	 */
844 	clone_pgd_range(swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
845 			initial_page_table + KERNEL_PGD_BOUNDARY,
846 			KERNEL_PGD_PTRS);
847 
848 	load_cr3(swapper_pg_dir);
849 	/*
850 	 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
851 	 * a cr3 based tlb flush, so the following __flush_tlb_all()
852 	 * will not flush anything because the cpu quirk which clears
853 	 * X86_FEATURE_PGE has not been invoked yet. Though due to the
854 	 * load_cr3() above the TLB has been flushed already. The
855 	 * quirk is invoked before subsequent calls to __flush_tlb_all()
856 	 * so proper operation is guaranteed.
857 	 */
858 	__flush_tlb_all();
859 #else
860 	printk(KERN_INFO "Command line: %s\n", boot_command_line);
861 #endif
862 
863 	/*
864 	 * If we have OLPC OFW, we might end up relocating the fixmap due to
865 	 * reserve_top(), so do this before touching the ioremap area.
866 	 */
867 	olpc_ofw_detect();
868 
869 	early_trap_init();
870 	early_cpu_init();
871 	early_ioremap_init();
872 
873 	setup_olpc_ofw_pgd();
874 
875 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
876 	screen_info = boot_params.screen_info;
877 	edid_info = boot_params.edid_info;
878 #ifdef CONFIG_X86_32
879 	apm_info.bios = boot_params.apm_bios_info;
880 	ist_info = boot_params.ist_info;
881 #endif
882 	saved_video_mode = boot_params.hdr.vid_mode;
883 	bootloader_type = boot_params.hdr.type_of_loader;
884 	if ((bootloader_type >> 4) == 0xe) {
885 		bootloader_type &= 0xf;
886 		bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
887 	}
888 	bootloader_version  = bootloader_type & 0xf;
889 	bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
890 
891 #ifdef CONFIG_BLK_DEV_RAM
892 	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
893 	rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
894 	rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
895 #endif
896 #ifdef CONFIG_EFI
897 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
898 		     EFI32_LOADER_SIGNATURE, 4)) {
899 		set_bit(EFI_BOOT, &efi.flags);
900 	} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
901 		     EFI64_LOADER_SIGNATURE, 4)) {
902 		set_bit(EFI_BOOT, &efi.flags);
903 		set_bit(EFI_64BIT, &efi.flags);
904 	}
905 
906 	if (efi_enabled(EFI_BOOT))
907 		efi_memblock_x86_reserve_range();
908 #endif
909 
910 	x86_init.oem.arch_setup();
911 
912 	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
913 	setup_memory_map();
914 	parse_setup_data();
915 
916 	copy_edd();
917 
918 	if (!boot_params.hdr.root_flags)
919 		root_mountflags &= ~MS_RDONLY;
920 	init_mm.start_code = (unsigned long) _text;
921 	init_mm.end_code = (unsigned long) _etext;
922 	init_mm.end_data = (unsigned long) _edata;
923 	init_mm.brk = _brk_end;
924 
925 	mpx_mm_init(&init_mm);
926 
927 #ifdef CONFIG_CMDLINE_BOOL
928 #ifdef CONFIG_CMDLINE_OVERRIDE
929 	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
930 #else
931 	if (builtin_cmdline[0]) {
932 		/* append boot loader cmdline to builtin */
933 		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
934 		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
935 		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
936 	}
937 #endif
938 #endif
939 
940 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
941 	*cmdline_p = command_line;
942 
943 	/*
944 	 * x86_configure_nx() is called before parse_early_param() to detect
945 	 * whether hardware doesn't support NX (so that the early EHCI debug
946 	 * console setup can safely call set_fixmap()). It may then be called
947 	 * again from within noexec_setup() during parsing early parameters
948 	 * to honor the respective command line option.
949 	 */
950 	x86_configure_nx();
951 
952 	parse_early_param();
953 
954 	x86_report_nx();
955 
956 	/* after early param, so could get panic from serial */
957 	memblock_x86_reserve_range_setup_data();
958 
959 	if (acpi_mps_check()) {
960 #ifdef CONFIG_X86_LOCAL_APIC
961 		disable_apic = 1;
962 #endif
963 		setup_clear_cpu_cap(X86_FEATURE_APIC);
964 	}
965 
966 #ifdef CONFIG_PCI
967 	if (pci_early_dump_regs)
968 		early_dump_pci_devices();
969 #endif
970 
971 	/* update the e820_saved too */
972 	e820_reserve_setup_data();
973 	finish_e820_parsing();
974 
975 	if (efi_enabled(EFI_BOOT))
976 		efi_init();
977 
978 	dmi_scan_machine();
979 	dmi_memdev_walk();
980 	dmi_set_dump_stack_arch_desc();
981 
982 	/*
983 	 * VMware detection requires dmi to be available, so this
984 	 * needs to be done after dmi_scan_machine, for the BP.
985 	 */
986 	init_hypervisor_platform();
987 
988 	x86_init.resources.probe_roms();
989 
990 	e820_add_kernel_range();
991 	trim_bios_range();
992 #ifdef CONFIG_X86_32
993 	if (ppro_with_ram_bug()) {
994 		e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
995 				  E820_RESERVED);
996 		sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
997 		printk(KERN_INFO "fixed physical RAM map:\n");
998 		e820_print_map("bad_ppro");
999 	}
1000 #else
1001 	early_gart_iommu_check();
1002 #endif
1003 
1004 	/*
1005 	 * partially used pages are not usable - thus
1006 	 * we are rounding upwards:
1007 	 */
1008 	max_pfn = e820_end_of_ram_pfn();
1009 
1010 	/* update e820 for memory not covered by WB MTRRs */
1011 	mtrr_bp_init();
1012 	if (mtrr_trim_uncached_memory(max_pfn))
1013 		max_pfn = e820_end_of_ram_pfn();
1014 
1015 	max_possible_pfn = max_pfn;
1016 
1017 #ifdef CONFIG_X86_32
1018 	/* max_low_pfn get updated here */
1019 	find_low_pfn_range();
1020 #else
1021 	check_x2apic();
1022 
1023 	/* How many end-of-memory variables you have, grandma! */
1024 	/* need this before calling reserve_initrd */
1025 	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
1026 		max_low_pfn = e820_end_of_low_ram_pfn();
1027 	else
1028 		max_low_pfn = max_pfn;
1029 
1030 	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
1031 #endif
1032 
1033 	/*
1034 	 * Find and reserve possible boot-time SMP configuration:
1035 	 */
1036 	find_smp_config();
1037 
1038 	reserve_ibft_region();
1039 
1040 	early_alloc_pgt_buf();
1041 
1042 	/*
1043 	 * Need to conclude brk, before memblock_x86_fill()
1044 	 *  it could use memblock_find_in_range, could overlap with
1045 	 *  brk area.
1046 	 */
1047 	reserve_brk();
1048 
1049 	cleanup_highmap();
1050 
1051 	memblock_set_current_limit(ISA_END_ADDRESS);
1052 	memblock_x86_fill();
1053 
1054 	if (efi_enabled(EFI_BOOT)) {
1055 		efi_fake_memmap();
1056 		efi_find_mirror();
1057 	}
1058 
1059 	/*
1060 	 * The EFI specification says that boot service code won't be called
1061 	 * after ExitBootServices(). This is, in fact, a lie.
1062 	 */
1063 	if (efi_enabled(EFI_MEMMAP))
1064 		efi_reserve_boot_services();
1065 
1066 	/* preallocate 4k for mptable mpc */
1067 	early_reserve_e820_mpc_new();
1068 
1069 #ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1070 	setup_bios_corruption_check();
1071 #endif
1072 
1073 #ifdef CONFIG_X86_32
1074 	printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1075 			(max_pfn_mapped<<PAGE_SHIFT) - 1);
1076 #endif
1077 
1078 	reserve_real_mode();
1079 
1080 	trim_platform_memory_ranges();
1081 	trim_low_memory_range();
1082 
1083 	init_mem_mapping();
1084 
1085 	early_trap_pf_init();
1086 
1087 	setup_real_mode();
1088 
1089 	memblock_set_current_limit(get_max_mapped());
1090 
1091 	/*
1092 	 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1093 	 */
1094 
1095 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1096 	if (init_ohci1394_dma_early)
1097 		init_ohci1394_dma_on_all_controllers();
1098 #endif
1099 	/* Allocate bigger log buffer */
1100 	setup_log_buf(1);
1101 
1102 	reserve_initrd();
1103 
1104 #if defined(CONFIG_ACPI) && defined(CONFIG_BLK_DEV_INITRD)
1105 	acpi_initrd_override((void *)initrd_start, initrd_end - initrd_start);
1106 #endif
1107 
1108 	vsmp_init();
1109 
1110 	io_delay_init();
1111 
1112 	/*
1113 	 * Parse the ACPI tables for possible boot-time SMP configuration.
1114 	 */
1115 	acpi_boot_table_init();
1116 
1117 	early_acpi_boot_init();
1118 
1119 	initmem_init();
1120 	dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1121 
1122 	/*
1123 	 * Reserve memory for crash kernel after SRAT is parsed so that it
1124 	 * won't consume hotpluggable memory.
1125 	 */
1126 	reserve_crashkernel();
1127 
1128 	memblock_find_dma_reserve();
1129 
1130 #ifdef CONFIG_KVM_GUEST
1131 	kvmclock_init();
1132 #endif
1133 
1134 	x86_init.paging.pagetable_init();
1135 
1136 	kasan_init();
1137 
1138 	if (boot_cpu_data.cpuid_level >= 0) {
1139 		/* A CPU has %cr4 if and only if it has CPUID */
1140 		mmu_cr4_features = __read_cr4();
1141 		if (trampoline_cr4_features)
1142 			*trampoline_cr4_features = mmu_cr4_features;
1143 	}
1144 
1145 #ifdef CONFIG_X86_32
1146 	/* sync back kernel address range */
1147 	clone_pgd_range(initial_page_table + KERNEL_PGD_BOUNDARY,
1148 			swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
1149 			KERNEL_PGD_PTRS);
1150 
1151 	/*
1152 	 * sync back low identity map too.  It is used for example
1153 	 * in the 32-bit EFI stub.
1154 	 */
1155 	clone_pgd_range(initial_page_table,
1156 			swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
1157 			min(KERNEL_PGD_PTRS, KERNEL_PGD_BOUNDARY));
1158 #endif
1159 
1160 	tboot_probe();
1161 
1162 	map_vsyscall();
1163 
1164 	generic_apic_probe();
1165 
1166 	early_quirks();
1167 
1168 	/*
1169 	 * Read APIC and some other early information from ACPI tables.
1170 	 */
1171 	acpi_boot_init();
1172 	sfi_init();
1173 	x86_dtb_init();
1174 
1175 	/*
1176 	 * get boot-time SMP configuration:
1177 	 */
1178 	if (smp_found_config)
1179 		get_smp_config();
1180 
1181 	prefill_possible_map();
1182 
1183 	init_cpu_to_node();
1184 
1185 	init_apic_mappings();
1186 	io_apic_init_mappings();
1187 
1188 	kvm_guest_init();
1189 
1190 	e820_reserve_resources();
1191 	e820_mark_nosave_regions(max_low_pfn);
1192 
1193 	x86_init.resources.reserve_resources();
1194 
1195 	e820_setup_gap();
1196 
1197 #ifdef CONFIG_VT
1198 #if defined(CONFIG_VGA_CONSOLE)
1199 	if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1200 		conswitchp = &vga_con;
1201 #elif defined(CONFIG_DUMMY_CONSOLE)
1202 	conswitchp = &dummy_con;
1203 #endif
1204 #endif
1205 	x86_init.oem.banner();
1206 
1207 	x86_init.timers.wallclock_init();
1208 
1209 	mcheck_init();
1210 
1211 	arch_init_ideal_nops();
1212 
1213 	register_refined_jiffies(CLOCK_TICK_RATE);
1214 
1215 #ifdef CONFIG_EFI
1216 	if (efi_enabled(EFI_BOOT))
1217 		efi_apply_memmap_quirks();
1218 #endif
1219 }
1220 
1221 #ifdef CONFIG_X86_32
1222 
1223 static struct resource video_ram_resource = {
1224 	.name	= "Video RAM area",
1225 	.start	= 0xa0000,
1226 	.end	= 0xbffff,
1227 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1228 };
1229 
1230 void __init i386_reserve_resources(void)
1231 {
1232 	request_resource(&iomem_resource, &video_ram_resource);
1233 	reserve_standard_io_resources();
1234 }
1235 
1236 #endif /* CONFIG_X86_32 */
1237 
1238 static struct notifier_block kernel_offset_notifier = {
1239 	.notifier_call = dump_kernel_offset
1240 };
1241 
1242 static int __init register_kernel_offset_dumper(void)
1243 {
1244 	atomic_notifier_chain_register(&panic_notifier_list,
1245 					&kernel_offset_notifier);
1246 	return 0;
1247 }
1248 __initcall(register_kernel_offset_dumper);
1249 
1250 void arch_show_smap(struct seq_file *m, struct vm_area_struct *vma)
1251 {
1252 	if (!boot_cpu_has(X86_FEATURE_OSPKE))
1253 		return;
1254 
1255 	seq_printf(m, "ProtectionKey:  %8u\n", vma_pkey(vma));
1256 }
1257