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