setup.c

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/*
 *  linux/arch/arm/kernel/setup.c
 *
 *  Copyright (C) 1995-2000 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/utsname.h>
#include <linux/blk.h>
#include <linux/console.h>
#include <linux/bootmem.h>
#include <linux/init.h>

#include <asm/elf.h>
#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/procinfo.h>
#include <asm/setup.h>
#include <asm/mach-types.h>

#include <asm/mach/arch.h>

#ifndef MEM_SIZE
#define MEM_SIZE	(16*1024*1024)
#endif

#ifndef CONFIG_CMDLINE
#define CONFIG_CMDLINE ""
#endif

extern void paging_init(struct meminfo *, struct machine_desc *desc);
extern void bootmem_init(struct meminfo *);
extern void reboot_setup(char *str);
extern void disable_hlt(void);
extern unsigned long memparse(char *ptr, char **retptr);
extern int root_mountflags;
extern int _stext, _text, _etext, _edata, _end;

unsigned int processor_id;
unsigned int compat;
unsigned int __machine_arch_type;
unsigned int system_rev;
unsigned int system_serial_low;
unsigned int system_serial_high;
unsigned int mem_fclk_21285 = 50000000;
unsigned int elf_hwcap;

#ifdef MULTI_CPU
struct processor processor;
#endif

struct drive_info_struct { char dummy[32]; } drive_info;

struct screen_info screen_info = {
 orig_video_lines:	30,
 orig_video_cols:	80,
 orig_video_mode:	0,
 orig_video_ega_bx:	0,
 orig_video_isVGA:	1,
 orig_video_points:	8
};

unsigned char aux_device_present;
char elf_platform[ELF_PLATFORM_SIZE];
char saved_command_line[COMMAND_LINE_SIZE];

static struct proc_info_item proc_info;
static const char *machine_name;
static char command_line[COMMAND_LINE_SIZE] = { 0, };

static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
static union { char c[4]; unsigned long l; } endian_test __initdata = { { 'l', '?', '?', 'b' } };
#define ENDIANNESS ((char)endian_test.l)

/*
 * Standard memory resources
 */
static struct resource mem_res[] = {
	{ "Video RAM",   0,     0,     IORESOURCE_MEM			},
	{ "Kernel code", 0,     0,     IORESOURCE_MEM			},
	{ "Kernel data", 0,     0,     IORESOURCE_MEM			}
};

#define video_ram   mem_res[0]
#define kernel_code mem_res[1]
#define kernel_data mem_res[2]

static struct resource io_res[] = {
	{ "reserved",    0x3bc, 0x3be, IORESOURCE_IO | IORESOURCE_BUSY },
	{ "reserved",    0x378, 0x37f, IORESOURCE_IO | IORESOURCE_BUSY },
	{ "reserved",    0x278, 0x27f, IORESOURCE_IO | IORESOURCE_BUSY }
};

#define lp0 io_res[0]
#define lp1 io_res[1]
#define lp2 io_res[2]

static void __init setup_processor(void)
{
	extern struct proc_info_list __proc_info_begin, __proc_info_end;
	struct proc_info_list *list;

	/*
	 * locate processor in the list of supported processor
	 * types.  The linker builds this table for us from the
	 * entries in arch/arm/mm/proc-*.S
	 */
	for (list = &__proc_info_begin; list < &__proc_info_end ; list++)
		if ((processor_id & list->cpu_mask) == list->cpu_val)
			break;

	/*
	 * If processor type is unrecognised, then we
	 * can do nothing...
	 */
	if (list >= &__proc_info_end) {
		printk("CPU configuration botched (ID %08x), unable "
		       "to continue.\n", processor_id);
		while (1);
	}

	proc_info = *list->info;

#ifdef MULTI_CPU
	processor = *list->proc;
#endif

	printk("Processor: %s %s revision %d\n",
	       proc_info.manufacturer, proc_info.cpu_name,
	       (int)processor_id & 15);

	sprintf(system_utsname.machine, "%s%c", list->arch_name, ENDIANNESS);
	sprintf(elf_platform, "%s%c", list->elf_name, ENDIANNESS);
	elf_hwcap = list->elf_hwcap;

	cpu_proc_init();
}

static struct machine_desc * __init setup_architecture(unsigned int nr)
{
	extern struct machine_desc __arch_info_begin, __arch_info_end;
	struct machine_desc *list;

	/*
	 * locate architecture in the list of supported architectures.
	 */
	for (list = &__arch_info_begin; list < &__arch_info_end; list++)
		if (list->nr == nr)
			break;

	/*
	 * If the architecture type is not recognised, then we
	 * can co nothing...
	 */
	if (list >= &__arch_info_end) {
		printk("Architecture configuration botched (nr %d), unable "
		       "to continue.\n", nr);
		while (1);
	}

	printk("Architecture: %s\n", list->name);
	if (compat)
		printk(KERN_WARNING "Using compatibility code "
			"scheduled for removal in v%d.%d.%d\n",
			compat >> 24, (compat >> 12) & 0x3ff,
			compat & 0x3ff);

	return list;
}

/*
 * Initial parsing of the command line.  We need to pick out the
 * memory size.  We look for mem=size@start, where start and size
 * are "size[KkMm]"
 */
static void __init
parse_cmdline(struct meminfo *mi, char **cmdline_p, char *from)
{
	char c = ' ', *to = command_line;
	int usermem = 0, len = 0;

	for (;;) {
		if (c == ' ' && !memcmp(from, "mem=", 4)) {
			unsigned long size, start;

			if (to != command_line)
				to -= 1;

			/*
			 * If the user specifies memory size, we
			 * blow away any automatically generated
			 * size.
			 */
			if (usermem == 0) {
				usermem = 1;
				mi->nr_banks = 0;
			}

			start = PHYS_OFFSET;
			size  = memparse(from + 4, &from);
			if (*from == '@')
				start = memparse(from + 1, &from);

			mi->bank[mi->nr_banks].start = start;
			mi->bank[mi->nr_banks].size  = size;
			mi->bank[mi->nr_banks].node  = 0;
			mi->nr_banks += 1;
		}
		c = *from++;
		if (!c)
			break;
		if (COMMAND_LINE_SIZE <= ++len)
			break;
		*to++ = c;
	}
	*to = '\0';
	*cmdline_p = command_line;
}

void __init
setup_ramdisk(int doload, int prompt, int image_start, unsigned int rd_sz)
{
#ifdef CONFIG_BLK_DEV_RAM
	extern int rd_doload, rd_prompt, rd_image_start, rd_size;

	rd_image_start = image_start;
	rd_prompt = prompt;
	rd_doload = doload;

	if (rd_sz)
		rd_size = rd_sz;
#endif
}

/*
 * initial ram disk
 */
void __init setup_initrd(unsigned int start, unsigned int size)
{
#ifdef CONFIG_BLK_DEV_INITRD
	if (start == 0)
		size = 0;
	initrd_start = start;
	initrd_end   = start + size;
#endif
}

static void __init
request_standard_resources(struct meminfo *mi, struct machine_desc *mdesc)
{
	struct resource *res;
	int i;

	kernel_code.start  = __virt_to_bus(init_mm.start_code);
	kernel_code.end    = __virt_to_bus(init_mm.end_code - 1);
	kernel_data.start  = __virt_to_bus(init_mm.end_code);
	kernel_data.end    = __virt_to_bus(init_mm.brk - 1);

	for (i = 0; i < mi->nr_banks; i++) {
		unsigned long virt_start, virt_end;

		if (mi->bank[i].size == 0)
			continue;

		virt_start = __phys_to_virt(mi->bank[i].start);
		virt_end   = virt_start + mi->bank[i].size - 1;

		res = alloc_bootmem_low(sizeof(*res));
		res->name  = "System RAM";
		res->start = __virt_to_bus(virt_start);
		res->end   = __virt_to_bus(virt_end);
		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;

		request_resource(&iomem_resource, res);

		if (kernel_code.start >= res->start &&
		    kernel_code.end <= res->end)
			request_resource(res, &kernel_code);
		if (kernel_data.start >= res->start &&
		    kernel_data.end <= res->end)
			request_resource(res, &kernel_data);
	}

	if (mdesc->video_start) {
		video_ram.start = mdesc->video_start;
		video_ram.end   = mdesc->video_end;
		request_resource(&iomem_resource, &video_ram);
	}

	/*
	 * Some machines don't have the possibility of ever
	 * possessing lp0, lp1 or lp2
	 */
	if (mdesc->reserve_lp0)
		request_resource(&ioport_resource, &lp0);
	if (mdesc->reserve_lp1)
		request_resource(&ioport_resource, &lp1);
	if (mdesc->reserve_lp2)
		request_resource(&ioport_resource, &lp2);
}

void __init setup_arch(char **cmdline_p)
{
	struct param_struct *params = NULL;
	struct machine_desc *mdesc;
	struct meminfo meminfo;
	char *from = default_command_line;

	memset(&meminfo, 0, sizeof(meminfo));

	setup_processor();

	ROOT_DEV = MKDEV(0, 255);

	mdesc = setup_architecture(machine_arch_type);
	machine_name = mdesc->name;

	if (mdesc->broken_hlt)
		disable_hlt();

	if (mdesc->soft_reboot)
		reboot_setup("s");

	if (mdesc->param_offset)
		params = phys_to_virt(mdesc->param_offset);

	if (mdesc->fixup)
		mdesc->fixup(mdesc, params, &from, &meminfo);

	if (params && params->u1.s.page_size != PAGE_SIZE) {
		printk(KERN_WARNING "Warning: bad configuration page, "
		       "trying to continue\n");
		params = NULL;
	}

	if (params) {
		ROOT_DEV	   = to_kdev_t(params->u1.s.rootdev);
		system_rev	   = params->u1.s.system_rev;
		system_serial_low  = params->u1.s.system_serial_low;
		system_serial_high = params->u1.s.system_serial_high;

		if (params->u1.s.mem_fclk_21285 > 0)
			mem_fclk_21285 = params->u1.s.mem_fclk_21285;  

		setup_ramdisk((params->u1.s.flags & FLAG_RDLOAD) == 0,
			      (params->u1.s.flags & FLAG_RDPROMPT) == 0,
			      params->u1.s.rd_start,
			      params->u1.s.ramdisk_size);

		setup_initrd(params->u1.s.initrd_start,
			     params->u1.s.initrd_size);

		if (!(params->u1.s.flags & FLAG_READONLY))
			root_mountflags &= ~MS_RDONLY;

		from = params->commandline;
	}

	if (meminfo.nr_banks == 0) {
		meminfo.nr_banks      = 1;
		meminfo.bank[0].start = PHYS_OFFSET;
		meminfo.bank[0].node  = 0;
		if (params)
			meminfo.bank[0].size = params->u1.s.nr_pages << PAGE_SHIFT;
		else
			meminfo.bank[0].size = MEM_SIZE;
	}

	init_mm.start_code = (unsigned long) &_text;
	init_mm.end_code   = (unsigned long) &_etext;
	init_mm.end_data   = (unsigned long) &_edata;
	init_mm.brk	   = (unsigned long) &_end;

	memcpy(saved_command_line, from, COMMAND_LINE_SIZE);
	saved_command_line[COMMAND_LINE_SIZE-1] = '\0';
	parse_cmdline(&meminfo, cmdline_p, from);
	bootmem_init(&meminfo);
	paging_init(&meminfo, mdesc);
	request_standard_resources(&meminfo, mdesc);

#ifdef CONFIG_VT
#if defined(CONFIG_VGA_CONSOLE)
	conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
	conswitchp = &dummy_con;
#endif
#endif
}

int get_cpuinfo(char * buffer)
{
	char *p = buffer;

	p += sprintf(p, "Processor\t: %s %s rev %d (%s)\n",
		     proc_info.manufacturer, proc_info.cpu_name,
		     (int)processor_id & 15, elf_platform);

	p += sprintf(p, "BogoMIPS\t: %lu.%02lu\n",
		     (loops_per_sec+2500) / 500000,
		     ((loops_per_sec+2500) / 5000) % 100);

	p += sprintf(p, "Hardware\t: %s\n", machine_name);

	p += sprintf(p, "Revision\t: %04x\n",
		     system_rev);

	p += sprintf(p, "Serial\t\t: %08x%08x\n",
		     system_serial_high,
		     system_serial_low);

	return p - buffer;
}