Viewing file:  misc-simple.c (4.9 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* arch/ppc/common/misc-simple.c
*
* Misc. bootloader code for many machines. This assumes you have are using
* a 6xx/7xx/74xx CPU in your machine. This assumes the chunk of memory
* below 8MB is free. Finally, it assumes you have a NS16550-style uart for
* your serial console. If a machine meets these requirements, it can quite
* likely use this code during boot.
*
* Author: Matt Porter <mporter@mvista.com>
* Derived from arch/ppc/boot/prep/misc.c
*
* Copyright 2001 MontaVista Software Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/types.h>
#include <linux/elf.h>
#include <linux/config.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/mmu.h>
#include "nonstdio.h"
#include "zlib.h"
unsigned long com_port;
char *avail_ram;
char *end_avail;
extern char _end[];
#ifdef CONFIG_CMDLINE
#define CMDLINE CONFIG_CMDLINE
#else
#define CMDLINE ""
#endif
char cmd_preset[] = CMDLINE;
char cmd_buf[256];
char *cmd_line = cmd_buf;
unsigned long initrd_start = 0, initrd_end = 0;
/* These values must be variables. If not, the compiler optimizer
* will remove some code, causing the size of the code to vary
* when these values are zero. This is bad because we first
* compile with these zero to determine the size and offsets
* in an image, than compile again with these set to the proper
* discovered value.
*/
unsigned int initrd_offset, initrd_size;
char *zimage_start;
int zimage_size;
extern void gunzip(void *, int, unsigned char *, int *);
extern unsigned long serial_init(int chan);
void
decompress_kernel(unsigned long load_addr, int num_words, unsigned long cksum)
{
int timer = 0;
extern unsigned long start;
char *cp, ch;
com_port = serial_init(0);
/* assume the chunk below 8M is free */
end_avail = (char *)0x00800000;
/*
* Reveal where we were loaded at and where we
* were relocated to.
*/
puts("loaded at: "); puthex(load_addr);
puts(" "); puthex((unsigned long)(load_addr + (4*num_words)));
puts("\n");
if ( (unsigned long)load_addr != (unsigned long)&start )
{
puts("relocated to: "); puthex((unsigned long)&start);
puts(" ");
puthex((unsigned long)((unsigned long)&start + (4*num_words)));
puts("\n");
}
/* we have to subtract 0x10000 here to correct for objdump including
the size of the elf header which we strip -- Cort */
zimage_start = (char *)(load_addr - 0x10000 + ZIMAGE_OFFSET);
zimage_size = ZIMAGE_SIZE;
initrd_offset = INITRD_OFFSET;
initrd_size = INITRD_SIZE;
if ( initrd_offset )
initrd_start = load_addr - 0x10000 + initrd_offset;
else
initrd_start = 0;
initrd_end = initrd_size + initrd_start;
/* Relocate the zImage */
avail_ram = (char *)PAGE_ALIGN((unsigned long)_end);
puts("zimage at: "); puthex((unsigned long)zimage_start);
puts(" "); puthex((unsigned long)(zimage_size+zimage_start));
puts("\n");
memcpy( (void *)avail_ram, (void *)zimage_start, zimage_size );
zimage_start = (char *)avail_ram;
puts("relocated to: "); puthex((unsigned long)zimage_start);
puts(" ");
puthex((unsigned long)zimage_size+(unsigned long)zimage_start);
puts("\n");
if ( initrd_start ) {
puts("initrd at: "); puthex(initrd_start);
puts(" "); puthex(initrd_end); puts("\n");
/* relocate initrd */
avail_ram = (char *)PAGE_ALIGN((unsigned long)zimage_size +
(unsigned long)zimage_start);
memcpy( (void *)avail_ram, (void *)initrd_start, initrd_size );
initrd_start = (unsigned long)avail_ram;
initrd_end = initrd_start + initrd_size;
puts("relocated to: "); puthex(initrd_start);
puts(" "); puthex(initrd_end); puts("\n");
}
avail_ram = (char *)0x00400000;
end_avail = (char *)0x00800000;
puts("avail ram: "); puthex((unsigned long)avail_ram); puts(" ");
puthex((unsigned long)end_avail); puts("\n");
/* Display standard Linux/PPC boot prompt for kernel args */
puts("\nLinux/PPC load: ");
cp = cmd_line;
memcpy (cmd_line, cmd_preset, sizeof(cmd_preset));
while ( *cp ) putc(*cp++);
while (timer++ < 5*1000) {
if (tstc()) {
while ((ch = getc()) != '\n' && ch != '\r') {
/* Test for backspace/delete */
if (ch == '\b' || ch == '\177') {
if (cp != cmd_line) {
cp--;
puts("\b \b");
}
/* Test for ^x/^u (and wipe the line) */
} else if (ch == '\030' || ch == '\025') {
while (cp != cmd_line) {
cp--;
puts("\b \b");
}
} else {
*cp++ = ch;
putc(ch);
}
}
break; /* Exit 'timer' loop */
}
udelay(1000); /* 1 msec */
}
*cp = 0;
puts("\n");
/* mappings on early boot can only handle 16M */
if ( (u32)(cmd_line) > (16<<20))
puts("cmd_line located > 16M\n");
puts("Uncompressing Linux...");
gunzip(0, 0x400000, zimage_start, &zimage_size);
puts("done.\n");
puts("Now booting the kernel\n");
}
|