xref: /linux/arch/arm/boot/compressed/misc.c (revision 8b1935e6a36b0967efc593d67ed3aebbfbc1f5b1)
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 #include <asm/unaligned.h>
30 
31 #ifdef STANDALONE_DEBUG
32 #define putstr printf
33 #else
34 
35 static void putstr(const char *ptr);
36 
37 #include <mach/uncompress.h>
38 
39 #ifdef CONFIG_DEBUG_ICEDCC
40 
41 #ifdef CONFIG_CPU_V6
42 
43 static void icedcc_putc(int ch)
44 {
45 	int status, i = 0x4000000;
46 
47 	do {
48 		if (--i < 0)
49 			return;
50 
51 		asm volatile ("mrc p14, 0, %0, c0, c1, 0" : "=r" (status));
52 	} while (status & (1 << 29));
53 
54 	asm("mcr p14, 0, %0, c0, c5, 0" : : "r" (ch));
55 }
56 
57 #elif defined(CONFIG_CPU_V7)
58 
59 static void icedcc_putc(int ch)
60 {
61 	asm(
62 	"wait:	mrc	p14, 0, pc, c0, c1, 0			\n\
63 		bcs	wait					\n\
64 		mcr     p14, 0, %0, c0, c5, 0			"
65 	: : "r" (ch));
66 }
67 
68 #elif defined(CONFIG_CPU_XSCALE)
69 
70 static void icedcc_putc(int ch)
71 {
72 	int status, i = 0x4000000;
73 
74 	do {
75 		if (--i < 0)
76 			return;
77 
78 		asm volatile ("mrc p14, 0, %0, c14, c0, 0" : "=r" (status));
79 	} while (status & (1 << 28));
80 
81 	asm("mcr p14, 0, %0, c8, c0, 0" : : "r" (ch));
82 }
83 
84 #else
85 
86 static void icedcc_putc(int ch)
87 {
88 	int status, i = 0x4000000;
89 
90 	do {
91 		if (--i < 0)
92 			return;
93 
94 		asm volatile ("mrc p14, 0, %0, c0, c0, 0" : "=r" (status));
95 	} while (status & 2);
96 
97 	asm("mcr p14, 0, %0, c1, c0, 0" : : "r" (ch));
98 }
99 
100 #endif
101 
102 #define putc(ch)	icedcc_putc(ch)
103 #endif
104 
105 static void putstr(const char *ptr)
106 {
107 	char c;
108 
109 	while ((c = *ptr++) != '\0') {
110 		if (c == '\n')
111 			putc('\r');
112 		putc(c);
113 	}
114 
115 	flush();
116 }
117 
118 #endif
119 
120 void *memcpy(void *__dest, __const void *__src, size_t __n)
121 {
122 	int i = 0;
123 	unsigned char *d = (unsigned char *)__dest, *s = (unsigned char *)__src;
124 
125 	for (i = __n >> 3; i > 0; i--) {
126 		*d++ = *s++;
127 		*d++ = *s++;
128 		*d++ = *s++;
129 		*d++ = *s++;
130 		*d++ = *s++;
131 		*d++ = *s++;
132 		*d++ = *s++;
133 		*d++ = *s++;
134 	}
135 
136 	if (__n & 1 << 2) {
137 		*d++ = *s++;
138 		*d++ = *s++;
139 		*d++ = *s++;
140 		*d++ = *s++;
141 	}
142 
143 	if (__n & 1 << 1) {
144 		*d++ = *s++;
145 		*d++ = *s++;
146 	}
147 
148 	if (__n & 1)
149 		*d++ = *s++;
150 
151 	return __dest;
152 }
153 
154 /*
155  * gzip delarations
156  */
157 extern char input_data[];
158 extern char input_data_end[];
159 
160 unsigned char *output_data;
161 unsigned long output_ptr;
162 
163 unsigned long free_mem_ptr;
164 unsigned long free_mem_end_ptr;
165 
166 #ifndef arch_error
167 #define arch_error(x)
168 #endif
169 
170 void error(char *x)
171 {
172 	arch_error(x);
173 
174 	putstr("\n\n");
175 	putstr(x);
176 	putstr("\n\n -- System halted");
177 
178 	while(1);	/* Halt */
179 }
180 
181 asmlinkage void __div0(void)
182 {
183 	error("Attempting division by 0!");
184 }
185 
186 extern void do_decompress(u8 *input, int len, u8 *output, void (*error)(char *x));
187 
188 #ifndef STANDALONE_DEBUG
189 
190 unsigned long
191 decompress_kernel(unsigned long output_start, unsigned long free_mem_ptr_p,
192 		unsigned long free_mem_ptr_end_p,
193 		int arch_id)
194 {
195 	unsigned char *tmp;
196 
197 	output_data		= (unsigned char *)output_start;
198 	free_mem_ptr		= free_mem_ptr_p;
199 	free_mem_end_ptr	= free_mem_ptr_end_p;
200 	__machine_arch_type	= arch_id;
201 
202 	arch_decomp_setup();
203 
204 	tmp = (unsigned char *) (((unsigned long)input_data_end) - 4);
205 	output_ptr = get_unaligned_le32(tmp);
206 
207 	putstr("Uncompressing Linux...");
208 	do_decompress(input_data, input_data_end - input_data,
209 			output_data, error);
210 	putstr(" done, booting the kernel.\n");
211 	return output_ptr;
212 }
213 #else
214 
215 char output_buffer[1500*1024];
216 
217 int main()
218 {
219 	output_data = output_buffer;
220 
221 	putstr("Uncompressing Linux...");
222 	decompress(input_data, input_data_end - input_data,
223 			NULL, NULL, output_data, NULL, error);
224 	putstr("done.\n");
225 	return 0;
226 }
227 #endif
228