setup.c

microwindows移植到S3C44B0的源码

/*
 * arch/v850/kernel/setup.c -- Arch-dependent initialization functions
 *
 *  Copyright (C) 2001,2002  NEC Corporation
 *  Copyright (C) 2001,2002  Miles Bader <[e-mail]>
 *
 * This file is subject to the terms and conditions of the GNU General
 * Public License.  See the file COPYING in the main directory of this
 * archive for more details.
 *
 * Written by Miles Bader <[e-mail]>
 */

#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/irq.h>
#include <linux/reboot.h>
#include <linux/personality.h>

#include <asm/irq.h>

#include "mach.h"

/* These symbols are all defined in the linker map to delineate various
   statically allocated regions of memory.  */

extern char _intv_start, _intv_end;
/* `kram' is only used if the kernel uses part of normal user RAM.  */
extern char _kram_start __attribute__ ((__weak__));
extern char _kram_end __attribute__ ((__weak__));
extern char _init_start, _init_end;
extern char _bootmap;
extern char _stext, _etext, _sdata, _edata, _sbss, _ebss;

char command_line[512];
char saved_command_line[512];

/* Memory not used by the kernel.  */
static unsigned long total_ram_pages;

/* System RAM.  */
static unsigned long ram_start = 0, ram_len = 0;

#define ADDR_TO_PAGE_UP(x)   ((((unsigned long)x) + PAGE_SIZE-1) >> PAGE_SHIFT)
#define ADDR_TO_PAGE(x)	     (((unsigned long)x) >> PAGE_SHIFT)
#define PAGE_TO_ADDR(x)	     (((unsigned long)x) << PAGE_SHIFT)

static void init_mem_alloc (unsigned long ram_start, unsigned long ram_len);

void __init setup_arch (char **cmdline)
{
	/* Keep a copy of command line */
	*cmdline = command_line;
	memcpy (saved_command_line, command_line, sizeof saved_command_line);
	saved_command_line[sizeof saved_command_line - 1] = '\0';

	console_verbose ();

	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) &_kram_end;

	/* Find out what mem this machine has.  */
	mach_get_physical_ram (&ram_start, &ram_len);
	/* ... and tell the kernel about it.  */
	init_mem_alloc (ram_start, ram_len);

	/* do machine-specific setups.  */
	mach_setup (cmdline);
}

void __init trap_init (void)
{
}


static void irq_nop (unsigned irq) { }
static unsigned irq_zero (unsigned irq) { return 0; }

static void nmi_end (unsigned irq)
{
	if (irq != IRQ_NMI (0)) {
		printk (KERN_CRIT "NMI %d is unrecoverable; restarting...",
			irq - IRQ_NMI (0));
		machine_restart (0);
	}
}

static struct hw_interrupt_type nmi_irq_type = {
	"NMI",
	irq_zero,		/* startup */
	irq_nop,		/* shutdown */
	irq_nop,		/* enable */
	irq_nop,		/* disable */
	irq_nop,		/* ack */
	nmi_end,		/* end */
};

void __init init_IRQ (void)
{
	init_irq_handlers (0, NUM_MACH_IRQS, 0);
	init_irq_handlers (IRQ_NMI (0), NUM_NMIS, &nmi_irq_type);
	mach_init_irqs ();
}


void __init mem_init (void)
{
	max_mapnr = MAP_NR (ram_start + ram_len);

	num_physpages = ADDR_TO_PAGE (ram_len);

	total_ram_pages = free_all_bootmem ();

	printk (KERN_INFO
		"Memory: %luK/%luK available"
		" (%luK kernel code, %luK data)\n",
		PAGE_TO_ADDR (nr_free_pages()) / 1024,
		ram_len / 1024,
		((unsigned long)&_etext - (unsigned long)&_stext) / 1024,
		((unsigned long)&_ebss - (unsigned long)&_sdata) / 1024);
}

void free_initmem (void)
{
	unsigned long ram_end = ram_start + ram_len;
	unsigned long start = PAGE_ALIGN ((unsigned long)(&_init_start));

	if (start >= ram_start && start < ram_end) {
		unsigned long addr;
		unsigned long end = PAGE_ALIGN ((unsigned long)(&_init_end));

		if (end > ram_end)
			end = ram_end;

		printk("Freeing unused kernel memory: %ldK freed\n",
		       (end - start) / 1024);

		for (addr = start; addr < end; addr += PAGE_SIZE) {
			mem_map_t *page = virt_to_page (addr);
			ClearPageReserved (page);
			set_page_count (page, 1);
			__free_page (page);
			total_ram_pages++;
		}
	}
}

void si_meminfo (struct sysinfo *info)
{
	info->totalram = total_ram_pages;
	info->sharedram = 0;
	info->freeram = nr_free_pages ();
	info->bufferram = atomic_read (&buffermem_pages);
	info->totalhigh = 0;
	info->freehigh = 0;
	info->mem_unit = PAGE_SIZE;
}


/* Initialize the `bootmem allocator'.  RAM_START and RAM_LEN identify
   what RAM may be used.  */
static void __init
init_bootmem_alloc (unsigned long ram_start, unsigned long ram_len)
{
	/* The part of the kernel that's in the same managed RAM space
	   used for general allocation.  */
	unsigned long kram_start = (unsigned long)&_kram_start;
	unsigned long kram_end = (unsigned long)&_kram_end;
	/* End of the managed RAM space.  */
	unsigned long ram_end = ram_start + ram_len;
	/* Address range of the interrupt vector table.  */
	unsigned long intv_start = (unsigned long)&_intv_start;
	unsigned long intv_end = (unsigned long)&_intv_end;
	/* True if the interrupt vectors are in the managed RAM area.  */
	int intv_in_ram = (intv_end > ram_start && intv_start < ram_end);
	/* True if the interrupt vectors are inside the kernel's RAM.  */
	int intv_in_kram = (intv_end > kram_start && intv_start < kram_end);
	/* A pointer to an optional function that reserves platform-specific
	   memory regions.  We declare the pointer `volatile' to avoid gcc
	   turning the call into a static call (the problem is that since
	   it's a weak symbol, a static call may end up trying to reference
	   the location 0x0, which is not always reachable).  */
	void (*volatile mrb) (void) = mach_reserve_bootmem;
	/* The bootmem allocator's allocation bitmap.  */
	unsigned long bootmap = (unsigned long)&_bootmap;
	unsigned long bootmap_len;

	/* Round bootmap location up to next page.  */
	bootmap = PAGE_TO_ADDR (ADDR_TO_PAGE_UP (bootmap));

	/* Initialize bootmem allocator.  */
	bootmap_len = init_bootmem_node (NODE_DATA (0),
					 ADDR_TO_PAGE (bootmap),
					 ADDR_TO_PAGE (PAGE_OFFSET),
					 ADDR_TO_PAGE (ram_end));

	/* Now make the RAM actually allocatable (it starts out `reserved'). */
	free_bootmem (ram_start, ram_len);

	if (kram_end > kram_start)
		/* Reserve the RAM part of the kernel's address space, so it
		   doesn't get allocated.  */
		reserve_bootmem (kram_start, kram_end - kram_start);
	
	if (intv_in_ram && !intv_in_kram)
		/* Reserve the interrupt vector space.  */
		reserve_bootmem (intv_start, intv_end - intv_start);

	if (bootmap >= ram_start && bootmap < ram_end)
		/* Reserve the bootmap space.  */
		reserve_bootmem (bootmap, bootmap_len);

	/* Let the platform-dependent code reserve some too.  */
	if (mrb)
		(*mrb) ();
}

/* Tell the kernel about what RAM it may use for memory allocation.  */
static void __init
init_mem_alloc (unsigned long ram_start, unsigned long ram_len)
{
	unsigned i;
	unsigned long zones_size[MAX_NR_ZONES];

	init_bootmem_alloc (ram_start, ram_len);

	for (i = 0; i < MAX_NR_ZONES; i++)
		zones_size[i] = 0;

	/* We stuff all the memory into one area, which includes the
	   initial gap from PAGE_OFFSET to ram_start.  */
	zones_size[ZONE_DMA]
		= ADDR_TO_PAGE (ram_len + (ram_start - PAGE_OFFSET));

	free_area_init_node (0, 0, 0, zones_size, PAGE_OFFSET, 0);
}