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/*
* BK Id: SCCS/s.misc.c 1.15 10/15/01 10:53:29 trini
*/
/*
* Adapted for PowerPC by Gary Thomas
*
* Rewritten by Cort Dougan (cort@cs.nmt.edu)
* One day to be replaced by a single bootloader for chrp/prep/pmac. -- Cort
*/
#include <linux/config.h>
#include <linux/types.h>
#include "zlib.h"
#include <asm/residual.h>
#include <linux/elf.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/mmu.h>
#ifdef CONFIG_8xx
#include <asm/mpc8xx.h>
#endif
#ifdef CONFIG_8260
#include <asm/mpc8260.h>
#endif
#include "nonstdio.h"
/*
* The following references are needed to cause the linker to pull in the
* gzimage.o and rdimage.o files. These object files are special,
* since they get placed into the .gzimage and .rdimage ELF sections
* of the zvmlinux and zvmlinux.initrd files.
*/
extern char dummy_for_gzimage;
extern char dummy_for_rdimage;
/*
* Please send me load/board info and such data for hardware not
* listed here so I can keep track since things are getting tricky
* with the different load addrs with different firmware. This will
* help to avoid breaking the load/boot process.
* -- Cort
*/
char *avail_ram;
char *end_avail;
/* Because of the limited amount of memory on embedded, it presents
* loading problems. The biggest is that we load this boot program
* into a relatively low memory address, and the Linux kernel Bss often
* extends into this space when it get loaded. When the kernel starts
* and zeros the BSS space, it also writes over the information we
* save here and pass to the kernel (command line and board info).
* On these boards, we grab some known memory holes to hold this information.
*/
char cmd_buf[256];
char *cmd_line = cmd_buf;
/* We need to pass along a 'dummy' com_port. */
unsigned long com_port = 0;
/* This is the default cmdline that will be given to the user at boot time..
* If none was specified at compile time, we'll give it one that should work.
* -- Tom */
#ifdef CONFIG_CMDLINE_BOOL
char compiled_string[] = CONFIG_CMDLINE;
#endif
char ramroot_string[] = "root=/dev/ram";
char netroot_string[] = "root=/dev/nfs rw";
bd_t hold_resid_buf;
bd_t *hold_residual = &hold_resid_buf;
unsigned long initrd_start = 0, initrd_end = 0;
char *zimage_start;
extern void gunzip(void *, int, unsigned char *, int *);
unsigned long
decompress_kernel(unsigned long load_addr, int num_words, unsigned long cksum, bd_t *bp)
{
int timer, zimage_size = ZIMAGE_SIZE;
extern unsigned long start;
char *cp, ch;
#ifdef CONFIG_8260
/* I don't know why I didn't do it this way on the 8xx.......
*/
embed_config(&bp);
serial_init(bp);
#endif
/* Grab some space for the command line and board info. Since
* we no longer use the ELF header, but it was loaded, grab
* that space.
*/
#ifdef CONFIG_MBX
cmd_line = (char *)(load_addr - 0x10000);
/* To be like everyone else, we need one too, although this
* board information is passed from the boot rom.
*/
bp->bi_baudrate = 9600;
#else
cmd_line = (char *)(0x200000);
#endif
hold_residual = (bd_t *)(cmd_line + sizeof(cmd_buf));
/* copy board data */
if (bp)
memcpy(hold_residual,bp,sizeof(bd_t));
/* Set end of memory available to us. It is always the highest
* memory address provided by the board information.
*/
end_avail = (char *)(bp->bi_memsize);
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");
}
if ( bp )
{
puts("board data at: "); puthex((unsigned long)bp);
puts(" ");
puthex((unsigned long)((unsigned long)bp + sizeof(bd_t)));
puts("\n");
puts("relocated to: ");
puthex((unsigned long)hold_residual);
puts(" ");
puthex((unsigned long)((unsigned long)hold_residual + sizeof(bd_t)));
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);
if ( INITRD_OFFSET )
initrd_start = load_addr - 0x10000 + INITRD_OFFSET;
else
initrd_start = 0;
initrd_end = INITRD_SIZE + initrd_start;
/*
* setup avail_ram - this is the first part of ram usable
* by the uncompress code. -- Cort
*/
avail_ram = (char *)PAGE_ALIGN((unsigned long)zimage_start+zimage_size);
if ( ((load_addr+(num_words*4)) > (unsigned long) avail_ram)
&& (load_addr <= 0x01000000) )
avail_ram = (char *)(load_addr+(num_words*4));
if ( (((unsigned long)&start+(num_words*4)) > (unsigned long) avail_ram)
&& (load_addr <= 0x01000000) )
avail_ram = (char *)((unsigned long)&start+(num_words*4));
/* relocate zimage */
puts("zimage at: "); puthex((unsigned long)zimage_start);
puts(" "); puthex((unsigned long)(zimage_size+zimage_start)); puts("\n");
/*
* There is no reason (yet) to relocate zImage for embedded boards.
* To support boot from flash rom on 8xx embedded boards, I
* assume if zimage start is over 16M we are booting from flash.
* In this case, avilable ram will start just above the space we
* have allocated for the command buffer and board information.
*/
if ((unsigned long)zimage_start > 0x01000000)
avail_ram = (char *)PAGE_ALIGN((unsigned long)hold_residual + sizeof(bd_t));
/* relocate initrd */
if ( initrd_start )
{
puts("initrd at: "); puthex(initrd_start);
puts(" "); puthex(initrd_end); puts("\n");
/* We only have to relocate initrd if we find it is in Flash
* rom. This is because the kernel thinks it can toss the
* pages into the free memory pool after it is done. Use
* the same 16M test.
*/
if ((unsigned long)initrd_start > 0x01000000) {
memcpy ((void *)PAGE_ALIGN(-PAGE_SIZE+(unsigned long)end_avail-INITRD_SIZE),
(void *)initrd_start,
INITRD_SIZE );
initrd_start = PAGE_ALIGN(-PAGE_SIZE+(unsigned long)end_avail-INITRD_SIZE);
initrd_end = initrd_start + INITRD_SIZE;
end_avail = (char *)initrd_start;
puts("relocated to: "); puthex(initrd_start);
puts(" "); puthex(initrd_end); puts("\n");
}
else {
avail_ram = (char *)PAGE_ALIGN((unsigned long)initrd_end);
}
}
puts("avail ram: "); puthex((unsigned long)avail_ram); puts(" ");
puthex((unsigned long)end_avail); puts("\n");
puts("\nLinux/PPC load: ");
timer = 0;
cp = cmd_line;
/* This is where we try and pick the right command line for booting.
* If we were given one at compile time, use it. It Is Right.
* If we weren't, see if we have a ramdisk. If so, thats root.
* When in doubt, give them the netroot (root=/dev/nfs rw) -- Tom */
#ifdef CONFIG_CMDLINE_BOOL
memcpy (cmd_line, compiled_string, sizeof(compiled_string));
#else
if (initrd_start)
memcpy (cmd_line, ramroot_string, sizeof(ramroot_string));
else
memcpy (cmd_line, netroot_string, sizeof(netroot_string));
#endif
while ( *cp ) putc(*cp++);
while (timer++ < 5*1000) {
if (tstc()) {
while ((ch = getc()) != '\n' && ch != '\r') {
if (ch == '\b' || ch == '\177') {
if (cp != cmd_line) {
cp--;
puts("\b \b");
}
} else if (ch == '\030' /* ^x */
|| ch == '\025') { /* ^u */
while (cp != cmd_line) {
cp--;
puts("\b \b");
}
} else {
*cp++ = ch;
putc(ch);
}
}
break; /* Exit 'timer' loop */
}
udelay(1000); /* 1 msec */
}
*cp = 0;
puts("\nUncompressing Linux...");
gunzip(0, 0x400000, zimage_start, &zimage_size);
puts("done.\n");
puts("Now booting the kernel\n");
return (unsigned long)hold_residual;
}
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