original_kernel/arch/alpha/boot/misc.c

173 lines
4.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* misc.c
*
* This is a collection of several routines from gzip-1.0.3
* adapted for Linux.
*
* malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
*
* Modified for ARM Linux by Russell King
*
* Nicolas Pitre <nico@visuaide.com> 1999/04/14 :
* For this code to run directly from Flash, all constant variables must
* be marked with 'const' and all other variables initialized at run-time
* only. This way all non constant variables will end up in the bss segment,
* which should point to addresses in RAM and cleared to 0 on start.
* This allows for a much quicker boot time.
*
* Modified for Alpha, from the ARM version, by Jay Estabrook 2003.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#define memzero(s,n) memset ((s),0,(n))
#define puts srm_printk
extern long srm_printk(const char *, ...)
__attribute__ ((format (printf, 1, 2)));
/*
* gzip declarations
*/
#define OF(args) args
#define STATIC static
typedef unsigned char uch;
typedef unsigned short ush;
typedef unsigned long ulg;
#define WSIZE 0x8000 /* Window size must be at least 32k, */
/* and a power of two */
static uch *inbuf; /* input buffer */
static uch *window; /* Sliding window buffer */
static unsigned insize; /* valid bytes in inbuf */
static unsigned inptr; /* index of next byte to be processed in inbuf */
static unsigned outcnt; /* bytes in output buffer */
/* gzip flag byte */
#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
#define COMMENT 0x10 /* bit 4 set: file comment present */
#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
#define RESERVED 0xC0 /* bit 6,7: reserved */
#define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf())
/* Diagnostic functions */
#ifdef DEBUG
# define Assert(cond,msg) {if(!(cond)) error(msg);}
# define Trace(x) fprintf x
# define Tracev(x) {if (verbose) fprintf x ;}
# define Tracevv(x) {if (verbose>1) fprintf x ;}
# define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
#else
# define Assert(cond,msg)
# define Trace(x)
# define Tracev(x)
# define Tracevv(x)
# define Tracec(c,x)
# define Tracecv(c,x)
#endif
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
static char *input_data;
static int input_data_size;
static uch *output_data;
static ulg output_ptr;
static ulg bytes_out;
static void error(char *m);
extern int end;
static ulg free_mem_ptr;
static ulg free_mem_end_ptr;
#define HEAP_SIZE 0x3000
#include "../../../lib/inflate.c"
/* ===========================================================================
* Fill the input buffer. This is called only when the buffer is empty
* and at least one byte is really needed.
*/
int fill_inbuf(void)
{
if (insize != 0)
error("ran out of input data");
inbuf = input_data;
insize = input_data_size;
inptr = 1;
return inbuf[0];
}
/* ===========================================================================
* Write the output window window[0..outcnt-1] and update crc and bytes_out.
* (Used for the decompressed data only.)
*/
void flush_window(void)
{
ulg c = crc;
unsigned n;
uch *in, *out, ch;
in = window;
out = &output_data[output_ptr];
for (n = 0; n < outcnt; n++) {
ch = *out++ = *in++;
c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
}
crc = c;
bytes_out += (ulg)outcnt;
output_ptr += (ulg)outcnt;
outcnt = 0;
/* puts("."); */
}
static void error(char *x)
{
puts("\n\n");
puts(x);
puts("\n\n -- System halted");
while(1); /* Halt */
}
unsigned int
decompress_kernel(void *output_start,
void *input_start,
size_t ksize,
size_t kzsize)
{
output_data = (uch *)output_start;
input_data = (uch *)input_start;
input_data_size = kzsize; /* use compressed size */
/* FIXME FIXME FIXME */
free_mem_ptr = (ulg)output_start + ksize;
free_mem_end_ptr = (ulg)output_start + ksize + 0x200000;
/* FIXME FIXME FIXME */
/* put in temp area to reduce initial footprint */
window = malloc(WSIZE);
makecrc();
/* puts("Uncompressing Linux..."); */
gunzip();
/* puts(" done, booting the kernel.\n"); */
return output_ptr;
}