1// SPDX-License-Identifier: GPL-2.0 2/* 3 * misc.c 4 * 5 * This is a collection of several routines from gzip-1.0.3 6 * adapted for Linux. 7 * 8 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994 9 * 10 * Modified for ARM Linux by Russell King 11 * 12 * Nicolas Pitre <nico@visuaide.com> 1999/04/14 : 13 * For this code to run directly from Flash, all constant variables must 14 * be marked with 'const' and all other variables initialized at run-time 15 * only. This way all non constant variables will end up in the bss segment, 16 * which should point to addresses in RAM and cleared to 0 on start. 17 * This allows for a much quicker boot time. 18 * 19 * Modified for Alpha, from the ARM version, by Jay Estabrook 2003. 20 */ 21 22#include <linux/kernel.h> 23#include <linux/slab.h> 24 25#include <linux/uaccess.h> 26 27#define memzero(s,n) memset ((s),0,(n)) 28#define puts srm_printk 29extern long srm_printk(const char *, ...) 30 __attribute__ ((format (printf, 1, 2))); 31 32/* 33 * gzip declarations 34 */ 35#define OF(args) args 36#define STATIC static 37 38typedef unsigned char uch; 39typedef unsigned short ush; 40typedef unsigned long ulg; 41 42#define WSIZE 0x8000 /* Window size must be at least 32k, */ 43 /* and a power of two */ 44 45static uch *inbuf; /* input buffer */ 46static uch *window; /* Sliding window buffer */ 47 48static unsigned insize; /* valid bytes in inbuf */ 49static unsigned inptr; /* index of next byte to be processed in inbuf */ 50static unsigned outcnt; /* bytes in output buffer */ 51 52/* gzip flag byte */ 53#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ 54#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ 55#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ 56#define ORIG_NAME 0x08 /* bit 3 set: original file name present */ 57#define COMMENT 0x10 /* bit 4 set: file comment present */ 58#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ 59#define RESERVED 0xC0 /* bit 6,7: reserved */ 60 61#define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf()) 62 63/* Diagnostic functions */ 64#ifdef DEBUG 65# define Assert(cond,msg) {if(!(cond)) error(msg);} 66# define Trace(x) fprintf x 67# define Tracev(x) {if (verbose) fprintf x ;} 68# define Tracevv(x) {if (verbose>1) fprintf x ;} 69# define Tracec(c,x) {if (verbose && (c)) fprintf x ;} 70# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} 71#else 72# define Assert(cond,msg) 73# define Trace(x) 74# define Tracev(x) 75# define Tracevv(x) 76# define Tracec(c,x) 77# define Tracecv(c,x) 78#endif 79 80static int fill_inbuf(void); 81static void flush_window(void); 82static void error(char *m); 83 84static char *input_data; 85static int input_data_size; 86 87static uch *output_data; 88static ulg output_ptr; 89static ulg bytes_out; 90 91static void error(char *m); 92 93extern int end; 94static ulg free_mem_ptr; 95static ulg free_mem_end_ptr; 96 97#define HEAP_SIZE 0x3000 98 99#include "../../../lib/inflate.c" 100 101/* =========================================================================== 102 * Fill the input buffer. This is called only when the buffer is empty 103 * and at least one byte is really needed. 104 */ 105int fill_inbuf(void) 106{ 107 if (insize != 0) 108 error("ran out of input data"); 109 110 inbuf = input_data; 111 insize = input_data_size; 112 113 inptr = 1; 114 return inbuf[0]; 115} 116 117/* =========================================================================== 118 * Write the output window window[0..outcnt-1] and update crc and bytes_out. 119 * (Used for the decompressed data only.) 120 */ 121void flush_window(void) 122{ 123 ulg c = crc; 124 unsigned n; 125 uch *in, *out, ch; 126 127 in = window; 128 out = &output_data[output_ptr]; 129 for (n = 0; n < outcnt; n++) { 130 ch = *out++ = *in++; 131 c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8); 132 } 133 crc = c; 134 bytes_out += (ulg)outcnt; 135 output_ptr += (ulg)outcnt; 136 outcnt = 0; 137/* puts("."); */ 138} 139 140static void error(char *x) 141{ 142 puts("\n\n"); 143 puts(x); 144 puts("\n\n -- System halted"); 145 146 while(1); /* Halt */ 147} 148 149unsigned int 150decompress_kernel(void *output_start, 151 void *input_start, 152 size_t ksize, 153 size_t kzsize) 154{ 155 output_data = (uch *)output_start; 156 input_data = (uch *)input_start; 157 input_data_size = kzsize; /* use compressed size */ 158 159 /* FIXME FIXME FIXME */ 160 free_mem_ptr = (ulg)output_start + ksize; 161 free_mem_end_ptr = (ulg)output_start + ksize + 0x200000; 162 /* FIXME FIXME FIXME */ 163 164 /* put in temp area to reduce initial footprint */ 165 window = malloc(WSIZE); 166 167 makecrc(); 168/* puts("Uncompressing Linux..."); */ 169 gunzip(); 170/* puts(" done, booting the kernel.\n"); */ 171 return output_ptr; 172} 173