File: /usr/src/linux/arch/sh/boot/compressed/misc.c
1 /*
2 * arch/sh/boot/compressed/misc.c
3 *
4 * This is a collection of several routines from gzip-1.0.3
5 * adapted for Linux.
6 *
7 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
8 *
9 * Adapted for SH by Stuart Menefy, Aug 1999
10 *
11 * Modified to use standard LinuxSH BIOS by Greg Banks 7Jul2000
12 */
13
14 #include <linux/config.h>
15 #include <asm/uaccess.h>
16 #ifdef CONFIG_SH_STANDARD_BIOS
17 #include <asm/sh_bios.h>
18 #endif
19
20 /*
21 * gzip declarations
22 */
23
24 #define OF(args) args
25 #define STATIC static
26
27 #undef memset
28 #undef memcpy
29 #define memzero(s, n) memset ((s), 0, (n))
30
31 typedef unsigned char uch;
32 typedef unsigned short ush;
33 typedef unsigned long ulg;
34
35 #define WSIZE 0x8000 /* Window size must be at least 32k, */
36 /* and a power of two */
37
38 static uch *inbuf; /* input buffer */
39 static uch window[WSIZE]; /* Sliding window buffer */
40
41 static unsigned insize = 0; /* valid bytes in inbuf */
42 static unsigned inptr = 0; /* index of next byte to be processed in inbuf */
43 static unsigned outcnt = 0; /* bytes in output buffer */
44
45 /* gzip flag byte */
46 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
47 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
48 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
49 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */
50 #define COMMENT 0x10 /* bit 4 set: file comment present */
51 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
52 #define RESERVED 0xC0 /* bit 6,7: reserved */
53
54 #define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf())
55
56 /* Diagnostic functions */
57 #ifdef DEBUG
58 # define Assert(cond,msg) {if(!(cond)) error(msg);}
59 # define Trace(x) fprintf x
60 # define Tracev(x) {if (verbose) fprintf x ;}
61 # define Tracevv(x) {if (verbose>1) fprintf x ;}
62 # define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
63 # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
64 #else
65 # define Assert(cond,msg)
66 # define Trace(x)
67 # define Tracev(x)
68 # define Tracevv(x)
69 # define Tracec(c,x)
70 # define Tracecv(c,x)
71 #endif
72
73 static int fill_inbuf(void);
74 static void flush_window(void);
75 static void error(char *m);
76 static void gzip_mark(void **);
77 static void gzip_release(void **);
78
79 extern char input_data[];
80 extern int input_len;
81
82 static long bytes_out = 0;
83 static uch *output_data;
84 static unsigned long output_ptr = 0;
85
86
87 static void *malloc(int size);
88 static void free(void *where);
89 static void error(char *m);
90 static void gzip_mark(void **);
91 static void gzip_release(void **);
92
93 static void puts(const char *);
94
95 extern int _text; /* Defined in vmlinux.lds.S */
96 extern int _end;
97 static unsigned long free_mem_ptr;
98 static unsigned long free_mem_end_ptr;
99
100 #define HEAP_SIZE 0x10000
101
102 #include "../../../../lib/inflate.c"
103
104 static void *malloc(int size)
105 {
106 void *p;
107
108 if (size <0) error("Malloc error\n");
109 if (free_mem_ptr == 0) error("Memory error\n");
110
111 free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
112
113 p = (void *)free_mem_ptr;
114 free_mem_ptr += size;
115
116 if (free_mem_ptr >= free_mem_end_ptr)
117 error("\nOut of memory\n");
118
119 return p;
120 }
121
122 static void free(void *where)
123 { /* Don't care */
124 }
125
126 static void gzip_mark(void **ptr)
127 {
128 *ptr = (void *) free_mem_ptr;
129 }
130
131 static void gzip_release(void **ptr)
132 {
133 free_mem_ptr = (long) *ptr;
134 }
135
136 #ifdef CONFIG_SH_STANDARD_BIOS
137 static int strlen(const char *s)
138 {
139 int i = 0;
140
141 while (*s++)
142 i++;
143 return i;
144 }
145
146 void puts(const char *s)
147 {
148 sh_bios_console_write(s, strlen(s));
149 }
150 #else
151 void puts(const char *s)
152 {
153 /* This should be updated to use the sh-sci routines */
154 }
155 #endif
156
157 void* memset(void* s, int c, size_t n)
158 {
159 int i;
160 char *ss = (char*)s;
161
162 for (i=0;i<n;i++) ss[i] = c;
163 return s;
164 }
165
166 void* memcpy(void* __dest, __const void* __src,
167 size_t __n)
168 {
169 int i;
170 char *d = (char *)__dest, *s = (char *)__src;
171
172 for (i=0;i<__n;i++) d[i] = s[i];
173 return __dest;
174 }
175
176 /* ===========================================================================
177 * Fill the input buffer. This is called only when the buffer is empty
178 * and at least one byte is really needed.
179 */
180 static int fill_inbuf(void)
181 {
182 if (insize != 0) {
183 error("ran out of input data\n");
184 }
185
186 inbuf = input_data;
187 insize = input_len;
188 inptr = 1;
189 return inbuf[0];
190 }
191
192 /* ===========================================================================
193 * Write the output window window[0..outcnt-1] and update crc and bytes_out.
194 * (Used for the decompressed data only.)
195 */
196 static void flush_window(void)
197 {
198 ulg c = crc; /* temporary variable */
199 unsigned n;
200 uch *in, *out, ch;
201
202 in = window;
203 out = &output_data[output_ptr];
204 for (n = 0; n < outcnt; n++) {
205 ch = *out++ = *in++;
206 c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
207 }
208 crc = c;
209 bytes_out += (ulg)outcnt;
210 output_ptr += (ulg)outcnt;
211 outcnt = 0;
212 }
213
214 static void error(char *x)
215 {
216 puts("\n\n");
217 puts(x);
218 puts("\n\n -- System halted");
219
220 while(1); /* Halt */
221 }
222
223 #define STACK_SIZE (4096)
224 long user_stack [STACK_SIZE];
225 long* stack_start = &user_stack[STACK_SIZE];
226
227 void decompress_kernel(void)
228 {
229 output_data = 0;
230 output_ptr = (unsigned long)&_text+0x20001000;
231 free_mem_ptr = (unsigned long)&_end;
232 free_mem_end_ptr = free_mem_ptr + HEAP_SIZE;
233
234 makecrc();
235 puts("Uncompressing Linux... ");
236 gunzip();
237 puts("Ok, booting the kernel.\n");
238 }
239