xref: /linux/arch/arm/boot/compressed/misc.c (revision 94bd217e2d683719ab21a4ac117d8a1b91cbedc9)
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 
19 unsigned int __machine_arch_type;
20 
21 #define _LINUX_STRING_H_
22 
23 #include <linux/compiler.h>	/* for inline */
24 #include <linux/types.h>	/* for size_t */
25 #include <linux/stddef.h>	/* for NULL */
26 #include <linux/linkage.h>
27 #include <asm/string.h>
28 
29 
30 static void putstr(const char *ptr);
31 extern void error(char *x);
32 
33 #include <mach/uncompress.h>
34 
35 #ifdef CONFIG_DEBUG_ICEDCC
36 
37 #if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7)
38 
39 static void icedcc_putc(int ch)
40 {
41 	int status, i = 0x4000000;
42 
43 	do {
44 		if (--i < 0)
45 			return;
46 
47 		asm volatile ("mrc p14, 0, %0, c0, c1, 0" : "=r" (status));
48 	} while (status & (1 << 29));
49 
50 	asm("mcr p14, 0, %0, c0, c5, 0" : : "r" (ch));
51 }
52 
53 
54 #elif defined(CONFIG_CPU_XSCALE)
55 
56 static void icedcc_putc(int ch)
57 {
58 	int status, i = 0x4000000;
59 
60 	do {
61 		if (--i < 0)
62 			return;
63 
64 		asm volatile ("mrc p14, 0, %0, c14, c0, 0" : "=r" (status));
65 	} while (status & (1 << 28));
66 
67 	asm("mcr p14, 0, %0, c8, c0, 0" : : "r" (ch));
68 }
69 
70 #else
71 
72 static void icedcc_putc(int ch)
73 {
74 	int status, i = 0x4000000;
75 
76 	do {
77 		if (--i < 0)
78 			return;
79 
80 		asm volatile ("mrc p14, 0, %0, c0, c0, 0" : "=r" (status));
81 	} while (status & 2);
82 
83 	asm("mcr p14, 0, %0, c1, c0, 0" : : "r" (ch));
84 }
85 
86 #endif
87 
88 #define putc(ch)	icedcc_putc(ch)
89 #endif
90 
91 static void putstr(const char *ptr)
92 {
93 	char c;
94 
95 	while ((c = *ptr++) != '\0') {
96 		if (c == '\n')
97 			putc('\r');
98 		putc(c);
99 	}
100 
101 	flush();
102 }
103 
104 
105 void *memcpy(void *__dest, __const void *__src, size_t __n)
106 {
107 	int i = 0;
108 	unsigned char *d = (unsigned char *)__dest, *s = (unsigned char *)__src;
109 
110 	for (i = __n >> 3; i > 0; i--) {
111 		*d++ = *s++;
112 		*d++ = *s++;
113 		*d++ = *s++;
114 		*d++ = *s++;
115 		*d++ = *s++;
116 		*d++ = *s++;
117 		*d++ = *s++;
118 		*d++ = *s++;
119 	}
120 
121 	if (__n & 1 << 2) {
122 		*d++ = *s++;
123 		*d++ = *s++;
124 		*d++ = *s++;
125 		*d++ = *s++;
126 	}
127 
128 	if (__n & 1 << 1) {
129 		*d++ = *s++;
130 		*d++ = *s++;
131 	}
132 
133 	if (__n & 1)
134 		*d++ = *s++;
135 
136 	return __dest;
137 }
138 
139 /*
140  * gzip declarations
141  */
142 extern char input_data[];
143 extern char input_data_end[];
144 
145 unsigned char *output_data;
146 
147 unsigned long free_mem_ptr;
148 unsigned long free_mem_end_ptr;
149 
150 #ifndef arch_error
151 #define arch_error(x)
152 #endif
153 
154 void error(char *x)
155 {
156 	arch_error(x);
157 
158 	putstr("\n\n");
159 	putstr(x);
160 	putstr("\n\n -- System halted");
161 
162 	while(1);	/* Halt */
163 }
164 
165 asmlinkage void __div0(void)
166 {
167 	error("Attempting division by 0!");
168 }
169 
170 extern int do_decompress(u8 *input, int len, u8 *output, void (*error)(char *x));
171 
172 
173 void
174 decompress_kernel(unsigned long output_start, unsigned long free_mem_ptr_p,
175 		unsigned long free_mem_ptr_end_p,
176 		int arch_id)
177 {
178 	int ret;
179 
180 	output_data		= (unsigned char *)output_start;
181 	free_mem_ptr		= free_mem_ptr_p;
182 	free_mem_end_ptr	= free_mem_ptr_end_p;
183 	__machine_arch_type	= arch_id;
184 
185 	arch_decomp_setup();
186 
187 	putstr("Uncompressing Linux...");
188 	ret = do_decompress(input_data, input_data_end - input_data,
189 			    output_data, error);
190 	if (ret)
191 		error("decompressor returned an error");
192 	else
193 		putstr(" done, booting the kernel.\n");
194 }
195