xref: /openbmc/linux/arch/alpha/boot/misc.c (revision 643d1f7f)
1 /*
2  * 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  * Modified for ARM Linux by Russell King
10  *
11  * Nicolas Pitre <nico@visuaide.com>  1999/04/14 :
12  *  For this code to run directly from Flash, all constant variables must
13  *  be marked with 'const' and all other variables initialized at run-time
14  *  only.  This way all non constant variables will end up in the bss segment,
15  *  which should point to addresses in RAM and cleared to 0 on start.
16  *  This allows for a much quicker boot time.
17  *
18  * Modified for Alpha, from the ARM version, by Jay Estabrook 2003.
19  */
20 
21 #include <linux/kernel.h>
22 
23 #include <asm/uaccess.h>
24 
25 #define memzero(s,n)	memset ((s),0,(n))
26 #define puts		srm_printk
27 extern long srm_printk(const char *, ...)
28      __attribute__ ((format (printf, 1, 2)));
29 
30 /*
31  * gzip delarations
32  */
33 #define OF(args)  args
34 #define STATIC static
35 
36 typedef unsigned char  uch;
37 typedef unsigned short ush;
38 typedef unsigned long  ulg;
39 
40 #define WSIZE 0x8000		/* Window size must be at least 32k, */
41 				/* and a power of two */
42 
43 static uch *inbuf;		/* input buffer */
44 static uch *window;		/* Sliding window buffer */
45 
46 static unsigned insize;		/* valid bytes in inbuf */
47 static unsigned inptr;		/* index of next byte to be processed in inbuf */
48 static unsigned outcnt;		/* bytes in output buffer */
49 
50 /* gzip flag byte */
51 #define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
52 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
53 #define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
54 #define ORIG_NAME    0x08 /* bit 3 set: original file name present */
55 #define COMMENT      0x10 /* bit 4 set: file comment present */
56 #define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
57 #define RESERVED     0xC0 /* bit 6,7:   reserved */
58 
59 #define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf())
60 
61 /* Diagnostic functions */
62 #ifdef DEBUG
63 #  define Assert(cond,msg) {if(!(cond)) error(msg);}
64 #  define Trace(x) fprintf x
65 #  define Tracev(x) {if (verbose) fprintf x ;}
66 #  define Tracevv(x) {if (verbose>1) fprintf x ;}
67 #  define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
68 #  define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
69 #else
70 #  define Assert(cond,msg)
71 #  define Trace(x)
72 #  define Tracev(x)
73 #  define Tracevv(x)
74 #  define Tracec(c,x)
75 #  define Tracecv(c,x)
76 #endif
77 
78 static int  fill_inbuf(void);
79 static void flush_window(void);
80 static void error(char *m);
81 static void gzip_mark(void **);
82 static void gzip_release(void **);
83 
84 static char *input_data;
85 static int  input_data_size;
86 
87 static uch *output_data;
88 static ulg output_ptr;
89 static ulg bytes_out;
90 
91 static void *malloc(int size);
92 static void free(void *where);
93 static void error(char *m);
94 static void gzip_mark(void **);
95 static void gzip_release(void **);
96 
97 extern int end;
98 static ulg free_mem_ptr;
99 static ulg free_mem_ptr_end;
100 
101 #define HEAP_SIZE 0x3000
102 
103 #include "../../../lib/inflate.c"
104 
105 static void *malloc(int size)
106 {
107 	void *p;
108 
109 	if (size <0) error("Malloc error");
110 	if (free_mem_ptr <= 0) error("Memory error");
111 
112 	free_mem_ptr = (free_mem_ptr + 3) & ~3;	/* Align */
113 
114 	p = (void *)free_mem_ptr;
115 	free_mem_ptr += size;
116 
117 	if (free_mem_ptr >= free_mem_ptr_end)
118 		error("Out of memory");
119 	return p;
120 }
121 
122 static void free(void *where)
123 { /* gzip_mark & gzip_release do the free */
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 /* ===========================================================================
137  * Fill the input buffer. This is called only when the buffer is empty
138  * and at least one byte is really needed.
139  */
140 int fill_inbuf(void)
141 {
142 	if (insize != 0)
143 		error("ran out of input data");
144 
145 	inbuf = input_data;
146 	insize = input_data_size;
147 
148 	inptr = 1;
149 	return inbuf[0];
150 }
151 
152 /* ===========================================================================
153  * Write the output window window[0..outcnt-1] and update crc and bytes_out.
154  * (Used for the decompressed data only.)
155  */
156 void flush_window(void)
157 {
158 	ulg c = crc;
159 	unsigned n;
160 	uch *in, *out, ch;
161 
162 	in = window;
163 	out = &output_data[output_ptr];
164 	for (n = 0; n < outcnt; n++) {
165 		ch = *out++ = *in++;
166 		c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
167 	}
168 	crc = c;
169 	bytes_out += (ulg)outcnt;
170 	output_ptr += (ulg)outcnt;
171 	outcnt = 0;
172 /*	puts("."); */
173 }
174 
175 static void error(char *x)
176 {
177 	puts("\n\n");
178 	puts(x);
179 	puts("\n\n -- System halted");
180 
181 	while(1);	/* Halt */
182 }
183 
184 unsigned int
185 decompress_kernel(void *output_start,
186 		  void *input_start,
187 		  size_t ksize,
188 		  size_t kzsize)
189 {
190 	output_data		= (uch *)output_start;
191 	input_data		= (uch *)input_start;
192 	input_data_size		= kzsize; /* use compressed size */
193 
194 	/* FIXME FIXME FIXME */
195 	free_mem_ptr		= (ulg)output_start + ksize;
196 	free_mem_ptr_end	= (ulg)output_start + ksize + 0x200000;
197 	/* FIXME FIXME FIXME */
198 
199 	/* put in temp area to reduce initial footprint */
200 	window = malloc(WSIZE);
201 
202 	makecrc();
203 /*	puts("Uncompressing Linux..."); */
204 	gunzip();
205 /*	puts(" done, booting the kernel.\n"); */
206 	return output_ptr;
207 }
208