1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * misc.c 4 * 5 * This is a collection of several routines from gzip-1.0.3 6 * adapted for Linux. 7 * 8 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994 9 * 10 * Modified for ARM Linux by Russell King 11 * 12 * Nicolas Pitre <nico@visuaide.com> 1999/04/14 : 13 * For this code to run directly from Flash, all constant variables must 14 * be marked with 'const' and all other variables initialized at run-time 15 * only. This way all non constant variables will end up in the bss segment, 16 * which should point to addresses in RAM and cleared to 0 on start. 17 * This allows for a much quicker boot time. 18 */ 19 20 unsigned int __machine_arch_type; 21 22 #include <linux/compiler.h> /* for inline */ 23 #include <linux/types.h> 24 #include <linux/linkage.h> 25 26 static void putstr(const char *ptr); 27 extern void error(char *x); 28 29 #include CONFIG_UNCOMPRESS_INCLUDE 30 31 #ifdef CONFIG_DEBUG_ICEDCC 32 33 #if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7) 34 35 static void icedcc_putc(int ch) 36 { 37 int status, i = 0x4000000; 38 39 do { 40 if (--i < 0) 41 return; 42 43 asm volatile ("mrc p14, 0, %0, c0, c1, 0" : "=r" (status)); 44 } while (status & (1 << 29)); 45 46 asm("mcr p14, 0, %0, c0, c5, 0" : : "r" (ch)); 47 } 48 49 50 #elif defined(CONFIG_CPU_XSCALE) 51 52 static void icedcc_putc(int ch) 53 { 54 int status, i = 0x4000000; 55 56 do { 57 if (--i < 0) 58 return; 59 60 asm volatile ("mrc p14, 0, %0, c14, c0, 0" : "=r" (status)); 61 } while (status & (1 << 28)); 62 63 asm("mcr p14, 0, %0, c8, c0, 0" : : "r" (ch)); 64 } 65 66 #else 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, c0, c0, 0" : "=r" (status)); 77 } while (status & 2); 78 79 asm("mcr p14, 0, %0, c1, c0, 0" : : "r" (ch)); 80 } 81 82 #endif 83 84 #define putc(ch) icedcc_putc(ch) 85 #endif 86 87 static void putstr(const char *ptr) 88 { 89 char c; 90 91 while ((c = *ptr++) != '\0') { 92 if (c == '\n') 93 putc('\r'); 94 putc(c); 95 } 96 97 flush(); 98 } 99 100 /* 101 * gzip declarations 102 */ 103 extern char input_data[]; 104 extern char input_data_end[]; 105 106 unsigned char *output_data; 107 108 unsigned long free_mem_ptr; 109 unsigned long free_mem_end_ptr; 110 111 #ifndef arch_error 112 #define arch_error(x) 113 #endif 114 115 void error(char *x) 116 { 117 arch_error(x); 118 119 putstr("\n\n"); 120 putstr(x); 121 putstr("\n\n -- System halted"); 122 123 while(1); /* Halt */ 124 } 125 126 asmlinkage void __div0(void) 127 { 128 error("Attempting division by 0!"); 129 } 130 131 unsigned long __stack_chk_guard; 132 133 void __stack_chk_guard_setup(void) 134 { 135 __stack_chk_guard = 0x000a0dff; 136 } 137 138 void __stack_chk_fail(void) 139 { 140 error("stack-protector: Kernel stack is corrupted\n"); 141 } 142 143 extern int do_decompress(u8 *input, int len, u8 *output, void (*error)(char *x)); 144 145 146 void 147 decompress_kernel(unsigned long output_start, unsigned long free_mem_ptr_p, 148 unsigned long free_mem_ptr_end_p, 149 int arch_id) 150 { 151 int ret; 152 153 __stack_chk_guard_setup(); 154 155 output_data = (unsigned char *)output_start; 156 free_mem_ptr = free_mem_ptr_p; 157 free_mem_end_ptr = free_mem_ptr_end_p; 158 __machine_arch_type = arch_id; 159 160 arch_decomp_setup(); 161 162 putstr("Uncompressing Linux..."); 163 ret = do_decompress(input_data, input_data_end - input_data, 164 output_data, error); 165 if (ret) 166 error("decompressor returned an error"); 167 else 168 putstr(" done, booting the kernel.\n"); 169 } 170