1/* 2 * Definitions and wrapper functions for kernel decompressor 3 * 4 * Copyright IBM Corp. 2010 5 * 6 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> 7 */ 8 9#include <asm/uaccess.h> 10#include <asm/page.h> 11#include <asm/sclp.h> 12#include <asm/ipl.h> 13#include "sizes.h" 14 15/* 16 * gzip declarations 17 */ 18#define STATIC static 19 20#undef memset 21#undef memcpy 22#undef memmove 23#define memmove memmove 24#define memzero(s, n) memset((s), 0, (n)) 25 26/* Symbols defined by linker scripts */ 27extern char input_data[]; 28extern int input_len; 29extern char _text, _end; 30extern char _bss, _ebss; 31 32static void error(char *m); 33 34static unsigned long free_mem_ptr; 35static unsigned long free_mem_end_ptr; 36 37#ifdef CONFIG_HAVE_KERNEL_BZIP2 38#define HEAP_SIZE 0x400000 39#else 40#define HEAP_SIZE 0x10000 41#endif 42 43#ifdef CONFIG_KERNEL_GZIP 44#include "../../../../lib/decompress_inflate.c" 45#endif 46 47#ifdef CONFIG_KERNEL_BZIP2 48#include "../../../../lib/decompress_bunzip2.c" 49#endif 50 51#ifdef CONFIG_KERNEL_LZ4 52#include "../../../../lib/decompress_unlz4.c" 53#endif 54 55#ifdef CONFIG_KERNEL_LZMA 56#include "../../../../lib/decompress_unlzma.c" 57#endif 58 59#ifdef CONFIG_KERNEL_LZO 60#include "../../../../lib/decompress_unlzo.c" 61#endif 62 63#ifdef CONFIG_KERNEL_XZ 64#include "../../../../lib/decompress_unxz.c" 65#endif 66 67static int puts(const char *s) 68{ 69 _sclp_print_early(s); 70 return 0; 71} 72 73void *memset(void *s, int c, size_t n) 74{ 75 char *xs; 76 77 xs = s; 78 while (n--) 79 *xs++ = c; 80 return s; 81} 82 83void *memcpy(void *dest, const void *src, size_t n) 84{ 85 const char *s = src; 86 char *d = dest; 87 88 while (n--) 89 *d++ = *s++; 90 return dest; 91} 92 93void *memmove(void *dest, const void *src, size_t n) 94{ 95 const char *s = src; 96 char *d = dest; 97 98 if (d <= s) { 99 while (n--) 100 *d++ = *s++; 101 } else { 102 d += n; 103 s += n; 104 while (n--) 105 *--d = *--s; 106 } 107 return dest; 108} 109 110static void error(char *x) 111{ 112 unsigned long long psw = 0x000a0000deadbeefULL; 113 114 puts("\n\n"); 115 puts(x); 116 puts("\n\n -- System halted"); 117 118 asm volatile("lpsw %0" : : "Q" (psw)); 119} 120 121/* 122 * Safe guard the ipl parameter block against a memory area that will be 123 * overwritten. The validity check for the ipl parameter block is complex 124 * (see cio_get_iplinfo and ipl_save_parameters) but if the pointer to 125 * the ipl parameter block intersects with the passed memory area we can 126 * safely assume that we can read from that memory. In that case just copy 127 * the memory to IPL_PARMBLOCK_ORIGIN even if there is no ipl parameter 128 * block. 129 */ 130static void check_ipl_parmblock(void *start, unsigned long size) 131{ 132 void *src, *dst; 133 134 src = (void *)(unsigned long) S390_lowcore.ipl_parmblock_ptr; 135 if (src + PAGE_SIZE <= start || src >= start + size) 136 return; 137 dst = (void *) IPL_PARMBLOCK_ORIGIN; 138 memmove(dst, src, PAGE_SIZE); 139 S390_lowcore.ipl_parmblock_ptr = IPL_PARMBLOCK_ORIGIN; 140} 141 142unsigned long decompress_kernel(void) 143{ 144 unsigned long output_addr; 145 unsigned char *output; 146 147 output_addr = ((unsigned long) &_end + HEAP_SIZE + 4095UL) & -4096UL; 148 check_ipl_parmblock((void *) 0, output_addr + SZ__bss_start); 149 memset(&_bss, 0, &_ebss - &_bss); 150 free_mem_ptr = (unsigned long)&_end; 151 free_mem_end_ptr = free_mem_ptr + HEAP_SIZE; 152 output = (unsigned char *) output_addr; 153 154#ifdef CONFIG_BLK_DEV_INITRD 155 /* 156 * Move the initrd right behind the end of the decompressed 157 * kernel image. 158 */ 159 if (INITRD_START && INITRD_SIZE && 160 INITRD_START < (unsigned long) output + SZ__bss_start) { 161 check_ipl_parmblock(output + SZ__bss_start, 162 INITRD_START + INITRD_SIZE); 163 memmove(output + SZ__bss_start, 164 (void *) INITRD_START, INITRD_SIZE); 165 INITRD_START = (unsigned long) output + SZ__bss_start; 166 } 167#endif 168 169 puts("Uncompressing Linux... "); 170 __decompress(input_data, input_len, NULL, NULL, output, 0, NULL, error); 171 puts("Ok, booting the kernel.\n"); 172 return (unsigned long) output; 173} 174 175