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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/apm_bios.h>
31 #include <linux/initrd.h>
32 #include <linux/bootmem.h>
33 #include <linux/seq_file.h>
34 #include <linux/console.h>
35 #include <linux/mca.h>
36 #include <linux/root_dev.h>
37 #include <linux/highmem.h>
38 #include <linux/module.h>
39 #include <linux/efi.h>
40 #include <linux/init.h>
41 #include <linux/edd.h>
42 #include <linux/iscsi_ibft.h>
43 #include <linux/nodemask.h>
44 #include <linux/kexec.h>
45 #include <linux/dmi.h>
46 #include <linux/pfn.h>
47 #include <linux/pci.h>
48 #include <asm/pci-direct.h>
49 #include <linux/init_ohci1394_dma.h>
50 #include <linux/kvm_para.h>
51 
52 #include <linux/errno.h>
53 #include <linux/kernel.h>
54 #include <linux/stddef.h>
55 #include <linux/unistd.h>
56 #include <linux/ptrace.h>
57 #include <linux/slab.h>
58 #include <linux/user.h>
59 #include <linux/delay.h>
60 
61 #include <linux/kallsyms.h>
62 #include <linux/cpufreq.h>
63 #include <linux/dma-mapping.h>
64 #include <linux/ctype.h>
65 #include <linux/uaccess.h>
66 
67 #include <linux/percpu.h>
68 #include <linux/crash_dump.h>
69 
70 #include <video/edid.h>
71 
72 #include <asm/mtrr.h>
73 #include <asm/apic.h>
74 #include <asm/e820.h>
75 #include <asm/mpspec.h>
76 #include <asm/setup.h>
77 #include <asm/arch_hooks.h>
78 #include <asm/efi.h>
79 #include <asm/sections.h>
80 #include <asm/dmi.h>
81 #include <asm/io_apic.h>
82 #include <asm/ist.h>
83 #include <asm/vmi.h>
84 #include <setup_arch.h>
85 #include <asm/bios_ebda.h>
86 #include <asm/cacheflush.h>
87 #include <asm/processor.h>
88 #include <asm/bugs.h>
89 
90 #include <asm/system.h>
91 #include <asm/vsyscall.h>
92 #include <asm/smp.h>
93 #include <asm/desc.h>
94 #include <asm/dma.h>
95 #include <asm/iommu.h>
96 #include <asm/gart.h>
97 #include <asm/mmu_context.h>
98 #include <asm/proto.h>
99 
100 #include <mach_apic.h>
101 #include <asm/paravirt.h>
102 #include <asm/hypervisor.h>
103 
104 #include <asm/percpu.h>
105 #include <asm/topology.h>
106 #include <asm/apicdef.h>
107 #ifdef CONFIG_X86_64
108 #include <asm/numa_64.h>
109 #endif
110 
111 #ifndef ARCH_SETUP
112 #define ARCH_SETUP
113 #endif
114 
115 #ifndef CONFIG_DEBUG_BOOT_PARAMS
116 struct boot_params __initdata boot_params;
117 #else
118 struct boot_params boot_params;
119 #endif
120 
121 /*
122  * Machine setup..
123  */
124 static struct resource data_resource = {
125 	.name	= "Kernel data",
126 	.start	= 0,
127 	.end	= 0,
128 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
129 };
130 
131 static struct resource code_resource = {
132 	.name	= "Kernel code",
133 	.start	= 0,
134 	.end	= 0,
135 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
136 };
137 
138 static struct resource bss_resource = {
139 	.name	= "Kernel bss",
140 	.start	= 0,
141 	.end	= 0,
142 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
143 };
144 
145 
146 #ifdef CONFIG_X86_32
147 /* This value is set up by the early boot code to point to the value
148    immediately after the boot time page tables.  It contains a *physical*
149    address, and must not be in the .bss segment! */
150 unsigned long init_pg_tables_start __initdata = ~0UL;
151 unsigned long init_pg_tables_end __initdata = ~0UL;
152 
153 static struct resource video_ram_resource = {
154 	.name	= "Video RAM area",
155 	.start	= 0xa0000,
156 	.end	= 0xbffff,
157 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
158 };
159 
160 /* cpu data as detected by the assembly code in head.S */
161 struct cpuinfo_x86 new_cpu_data __cpuinitdata = {0, 0, 0, 0, -1, 1, 0, 0, -1};
162 /* common cpu data for all cpus */
163 struct cpuinfo_x86 boot_cpu_data __read_mostly = {0, 0, 0, 0, -1, 1, 0, 0, -1};
164 EXPORT_SYMBOL(boot_cpu_data);
set_mca_bus(int x)165 static void set_mca_bus(int x)
166 {
167 #ifdef CONFIG_MCA
168 	MCA_bus = x;
169 #endif
170 }
171 
172 unsigned int def_to_bigsmp;
173 
174 /* for MCA, but anyone else can use it if they want */
175 unsigned int machine_id;
176 unsigned int machine_submodel_id;
177 unsigned int BIOS_revision;
178 
179 struct apm_info apm_info;
180 EXPORT_SYMBOL(apm_info);
181 
182 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
183 	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
184 struct ist_info ist_info;
185 EXPORT_SYMBOL(ist_info);
186 #else
187 struct ist_info ist_info;
188 #endif
189 
190 #else
191 struct cpuinfo_x86 boot_cpu_data __read_mostly;
192 EXPORT_SYMBOL(boot_cpu_data);
193 #endif
194 
195 
196 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
197 unsigned long mmu_cr4_features;
198 #else
199 unsigned long mmu_cr4_features = X86_CR4_PAE;
200 #endif
201 
202 /* Boot loader ID as an integer, for the benefit of proc_dointvec */
203 int bootloader_type;
204 
205 /*
206  * Early DMI memory
207  */
208 int dmi_alloc_index;
209 char dmi_alloc_data[DMI_MAX_DATA];
210 
211 /*
212  * Setup options
213  */
214 struct screen_info screen_info;
215 EXPORT_SYMBOL(screen_info);
216 struct edid_info edid_info;
217 EXPORT_SYMBOL_GPL(edid_info);
218 
219 extern int root_mountflags;
220 
221 unsigned long saved_video_mode;
222 
223 #define RAMDISK_IMAGE_START_MASK	0x07FF
224 #define RAMDISK_PROMPT_FLAG		0x8000
225 #define RAMDISK_LOAD_FLAG		0x4000
226 
227 static char __initdata command_line[COMMAND_LINE_SIZE];
228 #ifdef CONFIG_CMDLINE_BOOL
229 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
230 #endif
231 
232 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
233 struct edd edd;
234 #ifdef CONFIG_EDD_MODULE
235 EXPORT_SYMBOL(edd);
236 #endif
237 /**
238  * copy_edd() - Copy the BIOS EDD information
239  *              from boot_params into a safe place.
240  *
241  */
copy_edd(void)242 static inline void copy_edd(void)
243 {
244      memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
245 	    sizeof(edd.mbr_signature));
246      memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
247      edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
248      edd.edd_info_nr = boot_params.eddbuf_entries;
249 }
250 #else
copy_edd(void)251 static inline void copy_edd(void)
252 {
253 }
254 #endif
255 
256 #ifdef CONFIG_BLK_DEV_INITRD
257 
258 #ifdef CONFIG_X86_32
259 
260 #define MAX_MAP_CHUNK	(NR_FIX_BTMAPS << PAGE_SHIFT)
relocate_initrd(void)261 static void __init relocate_initrd(void)
262 {
263 
264 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
265 	u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
266 	u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
267 	u64 ramdisk_here;
268 	unsigned long slop, clen, mapaddr;
269 	char *p, *q;
270 
271 	/* We need to move the initrd down into lowmem */
272 	ramdisk_here = find_e820_area(0, end_of_lowmem, ramdisk_size,
273 					 PAGE_SIZE);
274 
275 	if (ramdisk_here == -1ULL)
276 		panic("Cannot find place for new RAMDISK of size %lld\n",
277 			 ramdisk_size);
278 
279 	/* Note: this includes all the lowmem currently occupied by
280 	   the initrd, we rely on that fact to keep the data intact. */
281 	reserve_early(ramdisk_here, ramdisk_here + ramdisk_size,
282 			 "NEW RAMDISK");
283 	initrd_start = ramdisk_here + PAGE_OFFSET;
284 	initrd_end   = initrd_start + ramdisk_size;
285 	printk(KERN_INFO "Allocated new RAMDISK: %08llx - %08llx\n",
286 			 ramdisk_here, ramdisk_here + ramdisk_size);
287 
288 	q = (char *)initrd_start;
289 
290 	/* Copy any lowmem portion of the initrd */
291 	if (ramdisk_image < end_of_lowmem) {
292 		clen = end_of_lowmem - ramdisk_image;
293 		p = (char *)__va(ramdisk_image);
294 		memcpy(q, p, clen);
295 		q += clen;
296 		ramdisk_image += clen;
297 		ramdisk_size  -= clen;
298 	}
299 
300 	/* Copy the highmem portion of the initrd */
301 	while (ramdisk_size) {
302 		slop = ramdisk_image & ~PAGE_MASK;
303 		clen = ramdisk_size;
304 		if (clen > MAX_MAP_CHUNK-slop)
305 			clen = MAX_MAP_CHUNK-slop;
306 		mapaddr = ramdisk_image & PAGE_MASK;
307 		p = early_memremap(mapaddr, clen+slop);
308 		memcpy(q, p+slop, clen);
309 		early_iounmap(p, clen+slop);
310 		q += clen;
311 		ramdisk_image += clen;
312 		ramdisk_size  -= clen;
313 	}
314 	/* high pages is not converted by early_res_to_bootmem */
315 	ramdisk_image = boot_params.hdr.ramdisk_image;
316 	ramdisk_size  = boot_params.hdr.ramdisk_size;
317 	printk(KERN_INFO "Move RAMDISK from %016llx - %016llx to"
318 		" %08llx - %08llx\n",
319 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
320 		ramdisk_here, ramdisk_here + ramdisk_size - 1);
321 }
322 #endif
323 
reserve_initrd(void)324 static void __init reserve_initrd(void)
325 {
326 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
327 	u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
328 	u64 ramdisk_end   = ramdisk_image + ramdisk_size;
329 	u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
330 
331 	if (!boot_params.hdr.type_of_loader ||
332 	    !ramdisk_image || !ramdisk_size)
333 		return;		/* No initrd provided by bootloader */
334 
335 	initrd_start = 0;
336 
337 	if (ramdisk_size >= (end_of_lowmem>>1)) {
338 		free_early(ramdisk_image, ramdisk_end);
339 		printk(KERN_ERR "initrd too large to handle, "
340 		       "disabling initrd\n");
341 		return;
342 	}
343 
344 	printk(KERN_INFO "RAMDISK: %08llx - %08llx\n", ramdisk_image,
345 			ramdisk_end);
346 
347 
348 	if (ramdisk_end <= end_of_lowmem) {
349 		/* All in lowmem, easy case */
350 		/*
351 		 * don't need to reserve again, already reserved early
352 		 * in i386_start_kernel
353 		 */
354 		initrd_start = ramdisk_image + PAGE_OFFSET;
355 		initrd_end = initrd_start + ramdisk_size;
356 		return;
357 	}
358 
359 #ifdef CONFIG_X86_32
360 	relocate_initrd();
361 #else
362 	printk(KERN_ERR "initrd extends beyond end of memory "
363 	       "(0x%08llx > 0x%08llx)\ndisabling initrd\n",
364 	       ramdisk_end, end_of_lowmem);
365 	initrd_start = 0;
366 #endif
367 	free_early(ramdisk_image, ramdisk_end);
368 }
369 #else
reserve_initrd(void)370 static void __init reserve_initrd(void)
371 {
372 }
373 #endif /* CONFIG_BLK_DEV_INITRD */
374 
parse_setup_data(void)375 static void __init parse_setup_data(void)
376 {
377 	struct setup_data *data;
378 	u64 pa_data;
379 
380 	if (boot_params.hdr.version < 0x0209)
381 		return;
382 	pa_data = boot_params.hdr.setup_data;
383 	while (pa_data) {
384 		data = early_memremap(pa_data, PAGE_SIZE);
385 		switch (data->type) {
386 		case SETUP_E820_EXT:
387 			parse_e820_ext(data, pa_data);
388 			break;
389 		default:
390 			break;
391 		}
392 		pa_data = data->next;
393 		early_iounmap(data, PAGE_SIZE);
394 	}
395 }
396 
e820_reserve_setup_data(void)397 static void __init e820_reserve_setup_data(void)
398 {
399 	struct setup_data *data;
400 	u64 pa_data;
401 	int found = 0;
402 
403 	if (boot_params.hdr.version < 0x0209)
404 		return;
405 	pa_data = boot_params.hdr.setup_data;
406 	while (pa_data) {
407 		data = early_memremap(pa_data, sizeof(*data));
408 		e820_update_range(pa_data, sizeof(*data)+data->len,
409 			 E820_RAM, E820_RESERVED_KERN);
410 		found = 1;
411 		pa_data = data->next;
412 		early_iounmap(data, sizeof(*data));
413 	}
414 	if (!found)
415 		return;
416 
417 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
418 	memcpy(&e820_saved, &e820, sizeof(struct e820map));
419 	printk(KERN_INFO "extended physical RAM map:\n");
420 	e820_print_map("reserve setup_data");
421 }
422 
reserve_early_setup_data(void)423 static void __init reserve_early_setup_data(void)
424 {
425 	struct setup_data *data;
426 	u64 pa_data;
427 	char buf[32];
428 
429 	if (boot_params.hdr.version < 0x0209)
430 		return;
431 	pa_data = boot_params.hdr.setup_data;
432 	while (pa_data) {
433 		data = early_memremap(pa_data, sizeof(*data));
434 		sprintf(buf, "setup data %x", data->type);
435 		reserve_early(pa_data, pa_data+sizeof(*data)+data->len, buf);
436 		pa_data = data->next;
437 		early_iounmap(data, sizeof(*data));
438 	}
439 }
440 
441 /*
442  * --------- Crashkernel reservation ------------------------------
443  */
444 
445 #ifdef CONFIG_KEXEC
446 
447 /**
448  * Reserve @size bytes of crashkernel memory at any suitable offset.
449  *
450  * @size: Size of the crashkernel memory to reserve.
451  * Returns the base address on success, and -1ULL on failure.
452  */
453 static
find_and_reserve_crashkernel(unsigned long long size)454 unsigned long long __init find_and_reserve_crashkernel(unsigned long long size)
455 {
456 	const unsigned long long alignment = 16<<20; 	/* 16M */
457 	unsigned long long start = 0LL;
458 
459 	while (1) {
460 		int ret;
461 
462 		start = find_e820_area(start, ULONG_MAX, size, alignment);
463 		if (start == -1ULL)
464 			return start;
465 
466 		/* try to reserve it */
467 		ret = reserve_bootmem_generic(start, size, BOOTMEM_EXCLUSIVE);
468 		if (ret >= 0)
469 			return start;
470 
471 		start += alignment;
472 	}
473 }
474 
get_total_mem(void)475 static inline unsigned long long get_total_mem(void)
476 {
477 	unsigned long long total;
478 
479 	total = max_low_pfn - min_low_pfn;
480 #ifdef CONFIG_HIGHMEM
481 	total += highend_pfn - highstart_pfn;
482 #endif
483 
484 	return total << PAGE_SHIFT;
485 }
486 
reserve_crashkernel(void)487 static void __init reserve_crashkernel(void)
488 {
489 	unsigned long long total_mem;
490 	unsigned long long crash_size, crash_base;
491 	int ret;
492 
493 	total_mem = get_total_mem();
494 
495 	ret = parse_crashkernel(boot_command_line, total_mem,
496 			&crash_size, &crash_base);
497 	if (ret != 0 || crash_size <= 0)
498 		return;
499 
500 	/* 0 means: find the address automatically */
501 	if (crash_base <= 0) {
502 		crash_base = find_and_reserve_crashkernel(crash_size);
503 		if (crash_base == -1ULL) {
504 			pr_info("crashkernel reservation failed. "
505 				"No suitable area found.\n");
506 			return;
507 		}
508 	} else {
509 		ret = reserve_bootmem_generic(crash_base, crash_size,
510 					BOOTMEM_EXCLUSIVE);
511 		if (ret < 0) {
512 			pr_info("crashkernel reservation failed - "
513 				"memory is in use\n");
514 			return;
515 		}
516 	}
517 
518 	printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
519 			"for crashkernel (System RAM: %ldMB)\n",
520 			(unsigned long)(crash_size >> 20),
521 			(unsigned long)(crash_base >> 20),
522 			(unsigned long)(total_mem >> 20));
523 
524 	crashk_res.start = crash_base;
525 	crashk_res.end   = crash_base + crash_size - 1;
526 	insert_resource(&iomem_resource, &crashk_res);
527 }
528 #else
reserve_crashkernel(void)529 static void __init reserve_crashkernel(void)
530 {
531 }
532 #endif
533 
534 static struct resource standard_io_resources[] = {
535 	{ .name = "dma1", .start = 0x00, .end = 0x1f,
536 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
537 	{ .name = "pic1", .start = 0x20, .end = 0x21,
538 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
539 	{ .name = "timer0", .start = 0x40, .end = 0x43,
540 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
541 	{ .name = "timer1", .start = 0x50, .end = 0x53,
542 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
543 	{ .name = "keyboard", .start = 0x60, .end = 0x60,
544 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
545 	{ .name = "keyboard", .start = 0x64, .end = 0x64,
546 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
547 	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
548 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
549 	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
550 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
551 	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
552 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
553 	{ .name = "fpu", .start = 0xf0, .end = 0xff,
554 		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
555 };
556 
reserve_standard_io_resources(void)557 static void __init reserve_standard_io_resources(void)
558 {
559 	int i;
560 
561 	/* request I/O space for devices used on all i[345]86 PCs */
562 	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
563 		request_resource(&ioport_resource, &standard_io_resources[i]);
564 
565 }
566 
567 /*
568  * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by
569  * is_kdump_kernel() to determine if we are booting after a panic. Hence
570  * ifdef it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
571  */
572 
573 #ifdef CONFIG_CRASH_DUMP
574 /* elfcorehdr= specifies the location of elf core header
575  * stored by the crashed kernel. This option will be passed
576  * by kexec loader to the capture kernel.
577  */
setup_elfcorehdr(char * arg)578 static int __init setup_elfcorehdr(char *arg)
579 {
580 	char *end;
581 	if (!arg)
582 		return -EINVAL;
583 	elfcorehdr_addr = memparse(arg, &end);
584 	return end > arg ? 0 : -EINVAL;
585 }
586 early_param("elfcorehdr", setup_elfcorehdr);
587 #endif
588 
default_update_genapic(void)589 static int __init default_update_genapic(void)
590 {
591 #ifdef CONFIG_X86_SMP
592 # if defined(CONFIG_X86_GENERICARCH) || defined(CONFIG_X86_64)
593 	genapic->wakeup_cpu = wakeup_secondary_cpu_via_init;
594 # endif
595 #endif
596 
597 	return 0;
598 }
599 
600 static struct x86_quirks default_x86_quirks __initdata = {
601 	.update_genapic         = default_update_genapic,
602 };
603 
604 struct x86_quirks *x86_quirks __initdata = &default_x86_quirks;
605 
606 #ifdef CONFIG_X86_RESERVE_LOW_64K
dmi_low_memory_corruption(const struct dmi_system_id * d)607 static int __init dmi_low_memory_corruption(const struct dmi_system_id *d)
608 {
609 	printk(KERN_NOTICE
610 		"%s detected: BIOS may corrupt low RAM, working around it.\n",
611 		d->ident);
612 
613 	e820_update_range(0, 0x10000, E820_RAM, E820_RESERVED);
614 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
615 
616 	return 0;
617 }
618 #endif
619 
620 /* List of systems that have known low memory corruption BIOS problems */
621 static struct dmi_system_id __initdata bad_bios_dmi_table[] = {
622 #ifdef CONFIG_X86_RESERVE_LOW_64K
623 	{
624 		.callback = dmi_low_memory_corruption,
625 		.ident = "AMI BIOS",
626 		.matches = {
627 			DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
628 		},
629 	},
630 	{
631 		.callback = dmi_low_memory_corruption,
632 		.ident = "Phoenix BIOS",
633 		.matches = {
634 			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies"),
635 		},
636 	},
637 #endif
638 	{}
639 };
640 
641 /*
642  * Determine if we were loaded by an EFI loader.  If so, then we have also been
643  * passed the efi memmap, systab, etc., so we should use these data structures
644  * for initialization.  Note, the efi init code path is determined by the
645  * global efi_enabled. This allows the same kernel image to be used on existing
646  * systems (with a traditional BIOS) as well as on EFI systems.
647  */
648 /*
649  * setup_arch - architecture-specific boot-time initializations
650  *
651  * Note: On x86_64, fixmaps are ready for use even before this is called.
652  */
653 
setup_arch(char ** cmdline_p)654 void __init setup_arch(char **cmdline_p)
655 {
656 #ifdef CONFIG_X86_32
657 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
658 	visws_early_detect();
659 	pre_setup_arch_hook();
660 #else
661 	printk(KERN_INFO "Command line: %s\n", boot_command_line);
662 #endif
663 
664 	/* VMI may relocate the fixmap; do this before touching ioremap area */
665 	vmi_init();
666 
667 	early_cpu_init();
668 	early_ioremap_init();
669 
670 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
671 	screen_info = boot_params.screen_info;
672 	edid_info = boot_params.edid_info;
673 #ifdef CONFIG_X86_32
674 	apm_info.bios = boot_params.apm_bios_info;
675 	ist_info = boot_params.ist_info;
676 	if (boot_params.sys_desc_table.length != 0) {
677 		set_mca_bus(boot_params.sys_desc_table.table[3] & 0x2);
678 		machine_id = boot_params.sys_desc_table.table[0];
679 		machine_submodel_id = boot_params.sys_desc_table.table[1];
680 		BIOS_revision = boot_params.sys_desc_table.table[2];
681 	}
682 #endif
683 	saved_video_mode = boot_params.hdr.vid_mode;
684 	bootloader_type = boot_params.hdr.type_of_loader;
685 
686 #ifdef CONFIG_BLK_DEV_RAM
687 	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
688 	rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
689 	rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
690 #endif
691 #ifdef CONFIG_EFI
692 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
693 #ifdef CONFIG_X86_32
694 		     "EL32",
695 #else
696 		     "EL64",
697 #endif
698 	 4)) {
699 		efi_enabled = 1;
700 		efi_reserve_early();
701 	}
702 #endif
703 
704 	ARCH_SETUP
705 
706 	setup_memory_map();
707 	parse_setup_data();
708 	/* update the e820_saved too */
709 	e820_reserve_setup_data();
710 
711 	copy_edd();
712 
713 	if (!boot_params.hdr.root_flags)
714 		root_mountflags &= ~MS_RDONLY;
715 	init_mm.start_code = (unsigned long) _text;
716 	init_mm.end_code = (unsigned long) _etext;
717 	init_mm.end_data = (unsigned long) _edata;
718 #ifdef CONFIG_X86_32
719 	init_mm.brk = init_pg_tables_end + PAGE_OFFSET;
720 #else
721 	init_mm.brk = (unsigned long) &_end;
722 #endif
723 
724 	code_resource.start = virt_to_phys(_text);
725 	code_resource.end = virt_to_phys(_etext)-1;
726 	data_resource.start = virt_to_phys(_etext);
727 	data_resource.end = virt_to_phys(_edata)-1;
728 	bss_resource.start = virt_to_phys(&__bss_start);
729 	bss_resource.end = virt_to_phys(&__bss_stop)-1;
730 
731 #ifdef CONFIG_CMDLINE_BOOL
732 #ifdef CONFIG_CMDLINE_OVERRIDE
733 	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
734 #else
735 	if (builtin_cmdline[0]) {
736 		/* append boot loader cmdline to builtin */
737 		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
738 		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
739 		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
740 	}
741 #endif
742 #endif
743 
744 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
745 	*cmdline_p = command_line;
746 
747 	parse_early_param();
748 
749 #ifdef CONFIG_X86_64
750 	check_efer();
751 #endif
752 
753 	/* Must be before kernel pagetables are setup */
754 	vmi_activate();
755 
756 	/* after early param, so could get panic from serial */
757 	reserve_early_setup_data();
758 
759 	if (acpi_mps_check()) {
760 #ifdef CONFIG_X86_LOCAL_APIC
761 		disable_apic = 1;
762 #endif
763 		setup_clear_cpu_cap(X86_FEATURE_APIC);
764 	}
765 
766 #ifdef CONFIG_PCI
767 	if (pci_early_dump_regs)
768 		early_dump_pci_devices();
769 #endif
770 
771 	finish_e820_parsing();
772 
773 	if (efi_enabled)
774 		efi_init();
775 
776 	dmi_scan_machine();
777 
778 	dmi_check_system(bad_bios_dmi_table);
779 
780 	/*
781 	 * VMware detection requires dmi to be available, so this
782 	 * needs to be done after dmi_scan_machine, for the BP.
783 	 */
784 	init_hypervisor(&boot_cpu_data);
785 
786 #ifdef CONFIG_X86_32
787 	probe_roms();
788 #endif
789 
790 	/* after parse_early_param, so could debug it */
791 	insert_resource(&iomem_resource, &code_resource);
792 	insert_resource(&iomem_resource, &data_resource);
793 	insert_resource(&iomem_resource, &bss_resource);
794 
795 
796 #ifdef CONFIG_X86_32
797 	if (ppro_with_ram_bug()) {
798 		e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
799 				  E820_RESERVED);
800 		sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
801 		printk(KERN_INFO "fixed physical RAM map:\n");
802 		e820_print_map("bad_ppro");
803 	}
804 #else
805 	early_gart_iommu_check();
806 #endif
807 
808 	/*
809 	 * partially used pages are not usable - thus
810 	 * we are rounding upwards:
811 	 */
812 	max_pfn = e820_end_of_ram_pfn();
813 
814 	/* preallocate 4k for mptable mpc */
815 	early_reserve_e820_mpc_new();
816 	/* update e820 for memory not covered by WB MTRRs */
817 	mtrr_bp_init();
818 	if (mtrr_trim_uncached_memory(max_pfn))
819 		max_pfn = e820_end_of_ram_pfn();
820 
821 #ifdef CONFIG_X86_32
822 	/* max_low_pfn get updated here */
823 	find_low_pfn_range();
824 #else
825 	num_physpages = max_pfn;
826 
827  	if (cpu_has_x2apic)
828  		check_x2apic();
829 
830 	/* How many end-of-memory variables you have, grandma! */
831 	/* need this before calling reserve_initrd */
832 	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
833 		max_low_pfn = e820_end_of_low_ram_pfn();
834 	else
835 		max_low_pfn = max_pfn;
836 
837 	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
838 #endif
839 
840 #ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
841 	setup_bios_corruption_check();
842 #endif
843 
844 	/* max_pfn_mapped is updated here */
845 	max_low_pfn_mapped = init_memory_mapping(0, max_low_pfn<<PAGE_SHIFT);
846 	max_pfn_mapped = max_low_pfn_mapped;
847 
848 #ifdef CONFIG_X86_64
849 	if (max_pfn > max_low_pfn) {
850 		max_pfn_mapped = init_memory_mapping(1UL<<32,
851 						     max_pfn<<PAGE_SHIFT);
852 		/* can we preseve max_low_pfn ?*/
853 		max_low_pfn = max_pfn;
854 	}
855 #endif
856 
857 	/*
858 	 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
859 	 */
860 
861 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
862 	if (init_ohci1394_dma_early)
863 		init_ohci1394_dma_on_all_controllers();
864 #endif
865 
866 	reserve_initrd();
867 
868 #ifdef CONFIG_X86_64
869 	vsmp_init();
870 #endif
871 
872 	io_delay_init();
873 
874 	/*
875 	 * Parse the ACPI tables for possible boot-time SMP configuration.
876 	 */
877 	acpi_boot_table_init();
878 
879 	early_acpi_boot_init();
880 
881 #ifdef CONFIG_ACPI_NUMA
882 	/*
883 	 * Parse SRAT to discover nodes.
884 	 */
885 	acpi_numa_init();
886 #endif
887 
888 	initmem_init(0, max_pfn);
889 
890 #ifdef CONFIG_ACPI_SLEEP
891 	/*
892 	 * Reserve low memory region for sleep support.
893 	 */
894 	acpi_reserve_bootmem();
895 #endif
896 #ifdef CONFIG_X86_FIND_SMP_CONFIG
897 	/*
898 	 * Find and reserve possible boot-time SMP configuration:
899 	 */
900 	find_smp_config();
901 #endif
902 	reserve_crashkernel();
903 
904 #ifdef CONFIG_X86_64
905 	/*
906 	 * dma32_reserve_bootmem() allocates bootmem which may conflict
907 	 * with the crashkernel command line, so do that after
908 	 * reserve_crashkernel()
909 	 */
910 	dma32_reserve_bootmem();
911 #endif
912 
913 	reserve_ibft_region();
914 
915 #ifdef CONFIG_KVM_CLOCK
916 	kvmclock_init();
917 #endif
918 
919 	paravirt_pagetable_setup_start(swapper_pg_dir);
920 	paging_init();
921 	paravirt_pagetable_setup_done(swapper_pg_dir);
922 	paravirt_post_allocator_init();
923 
924 #ifdef CONFIG_X86_64
925 	map_vsyscall();
926 #endif
927 
928 #ifdef CONFIG_X86_GENERICARCH
929 	generic_apic_probe();
930 #endif
931 
932 	early_quirks();
933 
934 	/*
935 	 * Read APIC and some other early information from ACPI tables.
936 	 */
937 	acpi_boot_init();
938 
939 #if defined(CONFIG_X86_MPPARSE) || defined(CONFIG_X86_VISWS)
940 	/*
941 	 * get boot-time SMP configuration:
942 	 */
943 	if (smp_found_config)
944 		get_smp_config();
945 #endif
946 
947 	prefill_possible_map();
948 
949 #ifdef CONFIG_X86_64
950 	init_cpu_to_node();
951 #endif
952 
953 	init_apic_mappings();
954 	ioapic_init_mappings();
955 
956 	/* need to wait for io_apic is mapped */
957 	probe_nr_irqs_gsi();
958 
959 	kvm_guest_init();
960 
961 	e820_reserve_resources();
962 	e820_mark_nosave_regions(max_low_pfn);
963 
964 #ifdef CONFIG_X86_32
965 	request_resource(&iomem_resource, &video_ram_resource);
966 #endif
967 	reserve_standard_io_resources();
968 
969 	e820_setup_gap();
970 
971 #ifdef CONFIG_VT
972 #if defined(CONFIG_VGA_CONSOLE)
973 	if (!efi_enabled || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
974 		conswitchp = &vga_con;
975 #elif defined(CONFIG_DUMMY_CONSOLE)
976 	conswitchp = &dummy_con;
977 #endif
978 #endif
979 }
980 
981 
982