1 /* 2 * Copyright (C) Paul Mackerras 1997. 3 * 4 * Updates for PPC64 by Todd Inglett, Dave Engebretsen & Peter Bergner. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 #include <stdarg.h> 12 #include <stddef.h> 13 #include "elf.h" 14 #include "page.h" 15 #include "string.h" 16 #include "stdio.h" 17 #include "ops.h" 18 #include "gunzip_util.h" 19 #include "reg.h" 20 21 static struct gunzip_state gzstate; 22 23 struct addr_range { 24 void *addr; 25 unsigned long size; 26 }; 27 28 #undef DEBUG 29 30 static struct addr_range prep_kernel(void) 31 { 32 char elfheader[256]; 33 void *vmlinuz_addr = _vmlinux_start; 34 unsigned long vmlinuz_size = _vmlinux_end - _vmlinux_start; 35 void *addr = 0; 36 struct elf_info ei; 37 int len; 38 39 /* gunzip the ELF header of the kernel */ 40 gunzip_start(&gzstate, vmlinuz_addr, vmlinuz_size); 41 gunzip_exactly(&gzstate, elfheader, sizeof(elfheader)); 42 43 if (!parse_elf64(elfheader, &ei) && !parse_elf32(elfheader, &ei)) 44 fatal("Error: not a valid PPC32 or PPC64 ELF file!\n\r"); 45 46 if (platform_ops.image_hdr) 47 platform_ops.image_hdr(elfheader); 48 49 /* We need to alloc the memsize: gzip will expand the kernel 50 * text/data, then possible rubbish we don't care about. But 51 * the kernel bss must be claimed (it will be zero'd by the 52 * kernel itself) 53 */ 54 printf("Allocating 0x%lx bytes for kernel ...\n\r", ei.memsize); 55 56 if (platform_ops.vmlinux_alloc) { 57 addr = platform_ops.vmlinux_alloc(ei.memsize); 58 } else { 59 /* 60 * Check if the kernel image (without bss) would overwrite the 61 * bootwrapper. The device tree has been moved in fdt_init() 62 * to an area allocated with malloc() (somewhere past _end). 63 */ 64 if ((unsigned long)_start < ei.loadsize) 65 fatal("Insufficient memory for kernel at address 0!" 66 " (_start=%p, uncompressed size=%08lx)\n\r", 67 _start, ei.loadsize); 68 69 if ((unsigned long)_end < ei.memsize) 70 fatal("The final kernel image would overwrite the " 71 "device tree\n\r"); 72 } 73 74 /* Finally, gunzip the kernel */ 75 printf("gunzipping (0x%p <- 0x%p:0x%p)...", addr, 76 vmlinuz_addr, vmlinuz_addr+vmlinuz_size); 77 /* discard up to the actual load data */ 78 gunzip_discard(&gzstate, ei.elfoffset - sizeof(elfheader)); 79 len = gunzip_finish(&gzstate, addr, ei.loadsize); 80 if (len != ei.loadsize) 81 fatal("ran out of data! only got 0x%x of 0x%lx bytes.\n\r", 82 len, ei.loadsize); 83 printf("done 0x%x bytes\n\r", len); 84 85 flush_cache(addr, ei.loadsize); 86 87 return (struct addr_range){addr, ei.memsize}; 88 } 89 90 static struct addr_range prep_initrd(struct addr_range vmlinux, void *chosen, 91 unsigned long initrd_addr, 92 unsigned long initrd_size) 93 { 94 /* If we have an image attached to us, it overrides anything 95 * supplied by the loader. */ 96 if (_initrd_end > _initrd_start) { 97 printf("Attached initrd image at 0x%p-0x%p\n\r", 98 _initrd_start, _initrd_end); 99 initrd_addr = (unsigned long)_initrd_start; 100 initrd_size = _initrd_end - _initrd_start; 101 } else if (initrd_size > 0) { 102 printf("Using loader supplied ramdisk at 0x%lx-0x%lx\n\r", 103 initrd_addr, initrd_addr + initrd_size); 104 } 105 106 /* If there's no initrd at all, we're done */ 107 if (! initrd_size) 108 return (struct addr_range){0, 0}; 109 110 /* 111 * If the initrd is too low it will be clobbered when the 112 * kernel relocates to its final location. In this case, 113 * allocate a safer place and move it. 114 */ 115 if (initrd_addr < vmlinux.size) { 116 void *old_addr = (void *)initrd_addr; 117 118 printf("Allocating 0x%lx bytes for initrd ...\n\r", 119 initrd_size); 120 initrd_addr = (unsigned long)malloc(initrd_size); 121 if (! initrd_addr) 122 fatal("Can't allocate memory for initial " 123 "ramdisk !\n\r"); 124 printf("Relocating initrd 0x%lx <- 0x%p (0x%lx bytes)\n\r", 125 initrd_addr, old_addr, initrd_size); 126 memmove((void *)initrd_addr, old_addr, initrd_size); 127 } 128 129 printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd_addr)); 130 131 /* Tell the kernel initrd address via device tree */ 132 setprop_val(chosen, "linux,initrd-start", (u32)(initrd_addr)); 133 setprop_val(chosen, "linux,initrd-end", (u32)(initrd_addr+initrd_size)); 134 135 return (struct addr_range){(void *)initrd_addr, initrd_size}; 136 } 137 138 /* A buffer that may be edited by tools operating on a zImage binary so as to 139 * edit the command line passed to vmlinux (by setting /chosen/bootargs). 140 * The buffer is put in it's own section so that tools may locate it easier. 141 */ 142 static char cmdline[COMMAND_LINE_SIZE] 143 __attribute__((__section__("__builtin_cmdline"))); 144 145 static void prep_cmdline(void *chosen) 146 { 147 if (cmdline[0] == '\0') 148 getprop(chosen, "bootargs", cmdline, COMMAND_LINE_SIZE-1); 149 150 printf("\n\rLinux/PowerPC load: %s", cmdline); 151 /* If possible, edit the command line */ 152 if (console_ops.edit_cmdline) 153 console_ops.edit_cmdline(cmdline, COMMAND_LINE_SIZE); 154 printf("\n\r"); 155 156 /* Put the command line back into the devtree for the kernel */ 157 setprop_str(chosen, "bootargs", cmdline); 158 } 159 160 struct platform_ops platform_ops; 161 struct dt_ops dt_ops; 162 struct console_ops console_ops; 163 struct loader_info loader_info; 164 165 void start(void) 166 { 167 struct addr_range vmlinux, initrd; 168 kernel_entry_t kentry; 169 unsigned long ft_addr = 0; 170 void *chosen; 171 172 /* Do this first, because malloc() could clobber the loader's 173 * command line. Only use the loader command line if a 174 * built-in command line wasn't set by an external tool */ 175 if ((loader_info.cmdline_len > 0) && (cmdline[0] == '\0')) 176 memmove(cmdline, loader_info.cmdline, 177 min(loader_info.cmdline_len, COMMAND_LINE_SIZE-1)); 178 179 if (console_ops.open && (console_ops.open() < 0)) 180 exit(); 181 if (platform_ops.fixups) 182 platform_ops.fixups(); 183 184 printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r", 185 _start, get_sp()); 186 187 /* Ensure that the device tree has a /chosen node */ 188 chosen = finddevice("/chosen"); 189 if (!chosen) 190 chosen = create_node(NULL, "chosen"); 191 192 vmlinux = prep_kernel(); 193 initrd = prep_initrd(vmlinux, chosen, 194 loader_info.initrd_addr, loader_info.initrd_size); 195 prep_cmdline(chosen); 196 197 printf("Finalizing device tree..."); 198 if (dt_ops.finalize) 199 ft_addr = dt_ops.finalize(); 200 if (ft_addr) 201 printf(" flat tree at 0x%lx\n\r", ft_addr); 202 else 203 printf(" using OF tree (promptr=%p)\n\r", loader_info.promptr); 204 205 if (console_ops.close) 206 console_ops.close(); 207 208 kentry = (kernel_entry_t) vmlinux.addr; 209 if (ft_addr) 210 kentry(ft_addr, 0, NULL); 211 else 212 kentry((unsigned long)initrd.addr, initrd.size, 213 loader_info.promptr); 214 215 /* console closed so printf in fatal below may not work */ 216 fatal("Error: Linux kernel returned to zImage boot wrapper!\n\r"); 217 } 218