xref: /openbmc/linux/arch/arm/boot/compressed/misc.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
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 
32 static void putstr(const char *ptr);
33 extern void error(char *x);
34 
35 #include <mach/uncompress.h>
36 
37 #ifdef CONFIG_DEBUG_ICEDCC
38 
39 #ifdef CONFIG_CPU_V6
40 
41 static void icedcc_putc(int ch)
42 {
43 	int status, i = 0x4000000;
44 
45 	do {
46 		if (--i < 0)
47 			return;
48 
49 		asm volatile ("mrc p14, 0, %0, c0, c1, 0" : "=r" (status));
50 	} while (status & (1 << 29));
51 
52 	asm("mcr p14, 0, %0, c0, c5, 0" : : "r" (ch));
53 }
54 
55 #elif defined(CONFIG_CPU_V7)
56 
57 static void icedcc_putc(int ch)
58 {
59 	asm(
60 	"wait:	mrc	p14, 0, pc, c0, c1, 0			\n\
61 		bcs	wait					\n\
62 		mcr     p14, 0, %0, c0, c5, 0			"
63 	: : "r" (ch));
64 }
65 
66 #elif defined(CONFIG_CPU_XSCALE)
67 
68 static void icedcc_putc(int ch)
69 {
70 	int status, i = 0x4000000;
71 
72 	do {
73 		if (--i < 0)
74 			return;
75 
76 		asm volatile ("mrc p14, 0, %0, c14, c0, 0" : "=r" (status));
77 	} while (status & (1 << 28));
78 
79 	asm("mcr p14, 0, %0, c8, c0, 0" : : "r" (ch));
80 }
81 
82 #else
83 
84 static void icedcc_putc(int ch)
85 {
86 	int status, i = 0x4000000;
87 
88 	do {
89 		if (--i < 0)
90 			return;
91 
92 		asm volatile ("mrc p14, 0, %0, c0, c0, 0" : "=r" (status));
93 	} while (status & 2);
94 
95 	asm("mcr p14, 0, %0, c1, c0, 0" : : "r" (ch));
96 }
97 
98 #endif
99 
100 #define putc(ch)	icedcc_putc(ch)
101 #endif
102 
103 static void putstr(const char *ptr)
104 {
105 	char c;
106 
107 	while ((c = *ptr++) != '\0') {
108 		if (c == '\n')
109 			putc('\r');
110 		putc(c);
111 	}
112 
113 	flush();
114 }
115 
116 
117 void *memcpy(void *__dest, __const void *__src, size_t __n)
118 {
119 	int i = 0;
120 	unsigned char *d = (unsigned char *)__dest, *s = (unsigned char *)__src;
121 
122 	for (i = __n >> 3; i > 0; i--) {
123 		*d++ = *s++;
124 		*d++ = *s++;
125 		*d++ = *s++;
126 		*d++ = *s++;
127 		*d++ = *s++;
128 		*d++ = *s++;
129 		*d++ = *s++;
130 		*d++ = *s++;
131 	}
132 
133 	if (__n & 1 << 2) {
134 		*d++ = *s++;
135 		*d++ = *s++;
136 		*d++ = *s++;
137 		*d++ = *s++;
138 	}
139 
140 	if (__n & 1 << 1) {
141 		*d++ = *s++;
142 		*d++ = *s++;
143 	}
144 
145 	if (__n & 1)
146 		*d++ = *s++;
147 
148 	return __dest;
149 }
150 
151 /*
152  * gzip delarations
153  */
154 extern char input_data[];
155 extern char input_data_end[];
156 
157 unsigned char *output_data;
158 unsigned long output_ptr;
159 
160 unsigned long free_mem_ptr;
161 unsigned long free_mem_end_ptr;
162 
163 #ifndef arch_error
164 #define arch_error(x)
165 #endif
166 
167 void error(char *x)
168 {
169 	arch_error(x);
170 
171 	putstr("\n\n");
172 	putstr(x);
173 	putstr("\n\n -- System halted");
174 
175 	while(1);	/* Halt */
176 }
177 
178 asmlinkage void __div0(void)
179 {
180 	error("Attempting division by 0!");
181 }
182 
183 extern void do_decompress(u8 *input, int len, u8 *output, void (*error)(char *x));
184 
185 
186 unsigned long
187 decompress_kernel(unsigned long output_start, unsigned long free_mem_ptr_p,
188 		unsigned long free_mem_ptr_end_p,
189 		int arch_id)
190 {
191 	unsigned char *tmp;
192 
193 	output_data		= (unsigned char *)output_start;
194 	free_mem_ptr		= free_mem_ptr_p;
195 	free_mem_end_ptr	= free_mem_ptr_end_p;
196 	__machine_arch_type	= arch_id;
197 
198 	arch_decomp_setup();
199 
200 	tmp = (unsigned char *) (((unsigned long)input_data_end) - 4);
201 	output_ptr = get_unaligned_le32(tmp);
202 
203 	putstr("Uncompressing Linux...");
204 	do_decompress(input_data, input_data_end - input_data,
205 			output_data, error);
206 	putstr(" done, booting the kernel.\n");
207 	return output_ptr;
208 }
209