setup.c

上传linux-jx2410的源代码

/*
 * Architecture-specific setup.
 *
 * Copyright (C) 1998-2001 Hewlett-Packard Co
 *	David Mosberger-Tang <[e-mail]>
 * Copyright (C) 1998, 1999, 2001 Stephane Eranian <[e-mail]>
 * Copyright (C) 2000, Rohit Seth <[e-mail]>
 * Copyright (C) 1999 VA Linux Systems
 * Copyright (C) 1999 Walt Drummond <[e-mail]>
 *
 * 11/12/01 D.Mosberger Convert get_cpuinfo() to seq_file based show_cpuinfo().
 * 04/04/00 D.Mosberger renamed cpu_initialized to cpu_online_map
 * 03/31/00 R.Seth	cpu_initialized and current->processor fixes
 * 02/04/00 D.Mosberger	some more get_cpuinfo fixes...
 * 02/01/00 R.Seth	fixed get_cpuinfo for SMP
 * 01/07/99 S.Eranian	added the support for command line argument
 * 06/24/99 W.Drummond	added boot_cpu_data.
 */
#include <linux/config.h>
#include <linux/init.h>

#include <linux/bootmem.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/reboot.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/threads.h>
#include <linux/console.h>

#include <asm/acpi-ext.h>
#include <asm/ia32.h>
#include <asm/page.h>
#include <asm/machvec.h>
#include <asm/processor.h>
#include <asm/sal.h>
#include <asm/system.h>
#include <asm/efi.h>
#include <asm/mca.h>
#include <asm/smp.h>

#ifdef CONFIG_BLK_DEV_RAM
# include <linux/blk.h>
#endif

#if defined(CONFIG_SMP) && (IA64_CPU_SIZE > PAGE_SIZE)
# error "struct cpuinfo_ia64 too big!"
#endif

#define MIN(a,b)	((a) < (b) ? (a) : (b))
#define MAX(a,b)	((a) > (b) ? (a) : (b))

extern char _end;

#ifdef CONFIG_NUMA
 struct cpuinfo_ia64 *boot_cpu_data;
#else
 struct cpuinfo_ia64 _cpu_data[NR_CPUS] __attribute__ ((section ("__special_page_section")));
#endif

unsigned long ia64_cycles_per_usec;
struct ia64_boot_param *ia64_boot_param;
struct screen_info screen_info;

unsigned long ia64_iobase;	/* virtual address for I/O accesses */

#define COMMAND_LINE_SIZE	512

char saved_command_line[COMMAND_LINE_SIZE]; /* used in proc filesystem */

/*
 * Entries defined so far:
 * 	- boot param structure itself
 * 	- memory map
 * 	- initrd (optional)
 * 	- command line string
 * 	- kernel code & data
 *
 * More could be added if necessary
 */
#define IA64_MAX_RSVD_REGIONS 5

struct rsvd_region {
	unsigned long start;	/* virtual address of beginning of element */
	unsigned long end;	/* virtual address of end of element + 1 */
};

/*
 * We use a special marker for the end of memory and it uses the extra (+1) slot
 */
static struct rsvd_region rsvd_region[IA64_MAX_RSVD_REGIONS + 1];
static int num_rsvd_regions;

static unsigned long bootmap_start; /* physical address where the bootmem map is located */

static int
find_max_pfn (unsigned long start, unsigned long end, void *arg)
{
	unsigned long *max_pfn = arg, pfn;

	pfn = (PAGE_ALIGN(end - 1) - PAGE_OFFSET) >> PAGE_SHIFT;
	if (pfn > *max_pfn)
		*max_pfn = pfn;
	return 0;
}

#define IGNORE_PFN0	1	/* XXX fix me: ignore pfn 0 until TLB miss handler is updated... */

/*
 * Free available memory based on the primitive map created from
 * the boot parameters. This routine does not assume the incoming
 * segments are sorted.
 */
static int
free_available_memory (unsigned long start, unsigned long end, void *arg)
{
	unsigned long range_start, range_end, prev_start;
	int i;

#if IGNORE_PFN0
	if (start == PAGE_OFFSET) {
		printk("warning: skipping physical page 0\n");
		start += PAGE_SIZE;
		if (start >= end) return 0;
	}
#endif
	/*
	 * lowest possible address(walker uses virtual)
	 */
	prev_start = PAGE_OFFSET;

	for (i = 0; i < num_rsvd_regions; ++i) {
		range_start = MAX(start, prev_start);
		range_end   = MIN(end, rsvd_region[i].start);

		if (range_start < range_end)
			free_bootmem(__pa(range_start), range_end - range_start);

		/* nothing more available in this segment */
		if (range_end == end) return 0;

		prev_start = rsvd_region[i].end;
	}
	/* end of memory marker allows full processing inside loop body */
	return 0;
}


static int
find_bootmap_location (unsigned long start, unsigned long end, void *arg)
{
	unsigned long needed = *(unsigned long *)arg;
	unsigned long range_start, range_end, free_start;
	int i;

#if IGNORE_PFN0
	if (start == PAGE_OFFSET) {
		start += PAGE_SIZE;
		if (start >= end) return 0;
	}
#endif

	free_start = PAGE_OFFSET;

	for (i = 0; i < num_rsvd_regions; i++) {
		range_start = MAX(start, free_start);
		range_end   = MIN(end, rsvd_region[i].start);

		if (range_end <= range_start) continue;	/* skip over empty range */

	       	if (range_end - range_start >= needed) {
			bootmap_start = __pa(range_start);
			return 1;	/* done */
		}

		/* nothing more available in this segment */
		if (range_end == end) return 0;

		free_start = rsvd_region[i].end;
	}
	return 0;
}

static void
sort_regions (struct rsvd_region *rsvd_region, int max)
{
	int j;

	/* simple bubble sorting */
	while (max--) {
		for (j = 0; j < max; ++j) {
			if (rsvd_region[j].start > rsvd_region[j+1].start) {
				struct rsvd_region tmp;
				tmp = rsvd_region[j];
				rsvd_region[j] = rsvd_region[j + 1];
				rsvd_region[j + 1] = tmp;
			}
		}
	}
}

static void
find_memory (void)
{
#	define KERNEL_END	((unsigned long) &_end)
	unsigned long bootmap_size;
	unsigned long max_pfn;
	int n = 0;

	/*
	 * none of the entries in this table overlap
	 */
	rsvd_region[n].start = (unsigned long) ia64_boot_param;
	rsvd_region[n].end   = rsvd_region[n].start + sizeof(*ia64_boot_param);
	n++;

	rsvd_region[n].start = (unsigned long) __va(ia64_boot_param->efi_memmap);
	rsvd_region[n].end   = rsvd_region[n].start + ia64_boot_param->efi_memmap_size;
	n++;

	rsvd_region[n].start = (unsigned long) __va(ia64_boot_param->command_line);
	rsvd_region[n].end   = (rsvd_region[n].start
				+ strlen(__va(ia64_boot_param->command_line)) + 1);
	n++;

	rsvd_region[n].start = KERNEL_START;
	rsvd_region[n].end   = KERNEL_END;
	n++;

#ifdef CONFIG_BLK_DEV_INITRD
	if (ia64_boot_param->initrd_start) {
		rsvd_region[n].start = (unsigned long)__va(ia64_boot_param->initrd_start);
		rsvd_region[n].end   = rsvd_region[n].start + ia64_boot_param->initrd_size;
		n++;
	}
#endif

	/* end of memory marker */
	rsvd_region[n].start = ~0UL;
	rsvd_region[n].end   = ~0UL;
	n++;

	num_rsvd_regions = n;

	sort_regions(rsvd_region, num_rsvd_regions);

	/* first find highest page frame number */
	max_pfn = 0;
	efi_memmap_walk(find_max_pfn, &max_pfn);

	/* how many bytes to cover all the pages */
	bootmap_size = bootmem_bootmap_pages(max_pfn) << PAGE_SHIFT;

	/* look for a location to hold the bootmap */
	bootmap_start = ~0UL;
	efi_memmap_walk(find_bootmap_location, &bootmap_size);
	if (bootmap_start == ~0UL)
		panic("Cannot find %ld bytes for bootmap\n", bootmap_size);

	bootmap_size = init_bootmem(bootmap_start >> PAGE_SHIFT, max_pfn);

	/* Free all available memory, then mark bootmem-map as being in use.  */
	efi_memmap_walk(free_available_memory, 0);
	reserve_bootmem(bootmap_start, bootmap_size);

#ifdef CONFIG_BLK_DEV_INITRD
	if (ia64_boot_param->initrd_start) {
		initrd_start = (unsigned long)__va(ia64_boot_param->initrd_start);
		initrd_end   = initrd_start+ia64_boot_param->initrd_size;

		printk("Initial ramdisk at: 0x%lx (%lu bytes)\n",
		       initrd_start, ia64_boot_param->initrd_size);
	}
#endif
}

void __init
setup_arch (char **cmdline_p)
{
	extern unsigned long ia64_iobase;

	unw_init();

	*cmdline_p = __va(ia64_boot_param->command_line);
	strncpy(saved_command_line, *cmdline_p, sizeof(saved_command_line));
	saved_command_line[COMMAND_LINE_SIZE-1] = '\0';		/* for safety */

	efi_init();

	find_memory();

#if 0
	/* XXX fix me */
	init_mm.start_code = (unsigned long) &_stext;
	init_mm.end_code = (unsigned long) &_etext;
	init_mm.end_data = (unsigned long) &_edata;
	init_mm.brk = (unsigned long) &_end;

	code_resource.start = virt_to_bus(&_text);
	code_resource.end = virt_to_bus(&_etext) - 1;
	data_resource.start = virt_to_bus(&_etext);
	data_resource.end = virt_to_bus(&_edata) - 1;
#endif

	/* process SAL system table: */
	ia64_sal_init(efi.sal_systab);

	/*
	 *  Set `iobase' to the appropriate address in region 6