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 "reg.h" 19 20 struct addr_range { 21 void *addr; 22 unsigned long size; 23 }; 24 25 #undef DEBUG 26 27 static struct addr_range prep_kernel(void) 28 { 29 char elfheader[256]; 30 unsigned char *vmlinuz_addr = (unsigned char *)_vmlinux_start; 31 unsigned long vmlinuz_size = _vmlinux_end - _vmlinux_start; 32 void *addr = 0; 33 struct elf_info ei; 34 long len; 35 int uncompressed_image = 0; 36 37 len = partial_decompress(vmlinuz_addr, vmlinuz_size, 38 elfheader, sizeof(elfheader), 0); 39 /* assume uncompressed data if -1 is returned */ 40 if (len == -1) { 41 uncompressed_image = 1; 42 memcpy(elfheader, vmlinuz_addr, sizeof(elfheader)); 43 printf("No valid compressed data found, assume uncompressed data\n\r"); 44 } 45 46 if (!parse_elf64(elfheader, &ei) && !parse_elf32(elfheader, &ei)) 47 fatal("Error: not a valid PPC32 or PPC64 ELF file!\n\r"); 48 49 if (platform_ops.image_hdr) 50 platform_ops.image_hdr(elfheader); 51 52 /* We need to alloc the memsize: gzip will expand the kernel 53 * text/data, then possible rubbish we don't care about. But 54 * the kernel bss must be claimed (it will be zero'd by the 55 * kernel itself) 56 */ 57 printf("Allocating 0x%lx bytes for kernel...\n\r", ei.memsize); 58 59 if (platform_ops.vmlinux_alloc) { 60 addr = platform_ops.vmlinux_alloc(ei.memsize); 61 } else { 62 /* 63 * Check if the kernel image (without bss) would overwrite the 64 * bootwrapper. The device tree has been moved in fdt_init() 65 * to an area allocated with malloc() (somewhere past _end). 66 */ 67 if ((unsigned long)_start < ei.loadsize) 68 fatal("Insufficient memory for kernel at address 0!" 69 " (_start=%p, uncompressed size=%08lx)\n\r", 70 _start, ei.loadsize); 71 72 if ((unsigned long)_end < ei.memsize) 73 fatal("The final kernel image would overwrite the " 74 "device tree\n\r"); 75 } 76 77 if (uncompressed_image) { 78 memcpy(addr, vmlinuz_addr + ei.elfoffset, ei.loadsize); 79 printf("0x%lx bytes of uncompressed data copied\n\r", 80 ei.loadsize); 81 goto out; 82 } 83 84 /* Finally, decompress the kernel */ 85 printf("Decompressing (0x%p <- 0x%p:0x%p)...\n\r", addr, 86 vmlinuz_addr, vmlinuz_addr+vmlinuz_size); 87 88 len = partial_decompress(vmlinuz_addr, vmlinuz_size, 89 addr, ei.loadsize, ei.elfoffset); 90 91 if (len < 0) 92 fatal("Decompression failed with error code %ld\n\r", len); 93 94 if (len != ei.loadsize) 95 fatal("Decompression error: got 0x%lx bytes, expected 0x%lx.\n\r", 96 len, ei.loadsize); 97 98 printf("Done! Decompressed 0x%lx bytes\n\r", len); 99 out: 100 flush_cache(addr, ei.loadsize); 101 102 return (struct addr_range){addr, ei.memsize}; 103 } 104 105 static struct addr_range prep_initrd(struct addr_range vmlinux, void *chosen, 106 unsigned long initrd_addr, 107 unsigned long initrd_size) 108 { 109 /* If we have an image attached to us, it overrides anything 110 * supplied by the loader. */ 111 if (_initrd_end > _initrd_start) { 112 printf("Attached initrd image at 0x%p-0x%p\n\r", 113 _initrd_start, _initrd_end); 114 initrd_addr = (unsigned long)_initrd_start; 115 initrd_size = _initrd_end - _initrd_start; 116 } else if (initrd_size > 0) { 117 printf("Using loader supplied ramdisk at 0x%lx-0x%lx\n\r", 118 initrd_addr, initrd_addr + initrd_size); 119 } 120 121 /* If there's no initrd at all, we're done */ 122 if (! initrd_size) 123 return (struct addr_range){0, 0}; 124 125 /* 126 * If the initrd is too low it will be clobbered when the 127 * kernel relocates to its final location. In this case, 128 * allocate a safer place and move it. 129 */ 130 if (initrd_addr < vmlinux.size) { 131 void *old_addr = (void *)initrd_addr; 132 133 printf("Allocating 0x%lx bytes for initrd ...\n\r", 134 initrd_size); 135 initrd_addr = (unsigned long)malloc(initrd_size); 136 if (! initrd_addr) 137 fatal("Can't allocate memory for initial " 138 "ramdisk !\n\r"); 139 printf("Relocating initrd 0x%lx <- 0x%p (0x%lx bytes)\n\r", 140 initrd_addr, old_addr, initrd_size); 141 memmove((void *)initrd_addr, old_addr, initrd_size); 142 } 143 144 printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd_addr)); 145 146 /* Tell the kernel initrd address via device tree */ 147 setprop_val(chosen, "linux,initrd-start", (u32)(initrd_addr)); 148 setprop_val(chosen, "linux,initrd-end", (u32)(initrd_addr+initrd_size)); 149 150 return (struct addr_range){(void *)initrd_addr, initrd_size}; 151 } 152 153 /* A buffer that may be edited by tools operating on a zImage binary so as to 154 * edit the command line passed to vmlinux (by setting /chosen/bootargs). 155 * The buffer is put in it's own section so that tools may locate it easier. 156 */ 157 static char cmdline[BOOT_COMMAND_LINE_SIZE] 158 __attribute__((__section__("__builtin_cmdline"))); 159 160 static void prep_cmdline(void *chosen) 161 { 162 unsigned int getline_timeout = 5000; 163 int v; 164 int n; 165 166 /* Wait-for-input time */ 167 n = getprop(chosen, "linux,cmdline-timeout", &v, sizeof(v)); 168 if (n == sizeof(v)) 169 getline_timeout = v; 170 171 if (cmdline[0] == '\0') 172 getprop(chosen, "bootargs", cmdline, BOOT_COMMAND_LINE_SIZE-1); 173 174 printf("\n\rLinux/PowerPC load: %s", cmdline); 175 176 /* If possible, edit the command line */ 177 if (console_ops.edit_cmdline && getline_timeout) 178 console_ops.edit_cmdline(cmdline, BOOT_COMMAND_LINE_SIZE, getline_timeout); 179 180 printf("\n\r"); 181 182 /* Put the command line back into the devtree for the kernel */ 183 setprop_str(chosen, "bootargs", cmdline); 184 } 185 186 struct platform_ops platform_ops; 187 struct dt_ops dt_ops; 188 struct console_ops console_ops; 189 struct loader_info loader_info; 190 191 void start(void) 192 { 193 struct addr_range vmlinux, initrd; 194 kernel_entry_t kentry; 195 unsigned long ft_addr = 0; 196 void *chosen; 197 198 /* Do this first, because malloc() could clobber the loader's 199 * command line. Only use the loader command line if a 200 * built-in command line wasn't set by an external tool */ 201 if ((loader_info.cmdline_len > 0) && (cmdline[0] == '\0')) 202 memmove(cmdline, loader_info.cmdline, 203 min(loader_info.cmdline_len, BOOT_COMMAND_LINE_SIZE-1)); 204 205 if (console_ops.open && (console_ops.open() < 0)) 206 exit(); 207 if (platform_ops.fixups) 208 platform_ops.fixups(); 209 210 printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r", 211 _start, get_sp()); 212 213 /* Ensure that the device tree has a /chosen node */ 214 chosen = finddevice("/chosen"); 215 if (!chosen) 216 chosen = create_node(NULL, "chosen"); 217 218 vmlinux = prep_kernel(); 219 initrd = prep_initrd(vmlinux, chosen, 220 loader_info.initrd_addr, loader_info.initrd_size); 221 prep_cmdline(chosen); 222 223 printf("Finalizing device tree..."); 224 if (dt_ops.finalize) 225 ft_addr = dt_ops.finalize(); 226 if (ft_addr) 227 printf(" flat tree at 0x%lx\n\r", ft_addr); 228 else 229 printf(" using OF tree (promptr=%p)\n\r", loader_info.promptr); 230 231 if (console_ops.close) 232 console_ops.close(); 233 234 kentry = (kernel_entry_t) vmlinux.addr; 235 if (ft_addr) { 236 if(platform_ops.kentry) 237 platform_ops.kentry(ft_addr, vmlinux.addr); 238 else 239 kentry(ft_addr, 0, NULL); 240 } 241 else 242 kentry((unsigned long)initrd.addr, initrd.size, 243 loader_info.promptr); 244 245 /* console closed so printf in fatal below may not work */ 246 fatal("Error: Linux kernel returned to zImage boot wrapper!\n\r"); 247 } 248