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 "flatdevtree.h" 20 #include "reg.h" 21 22 extern char _start[]; 23 extern char __bss_start[]; 24 extern char _end[]; 25 extern char _vmlinux_start[]; 26 extern char _vmlinux_end[]; 27 extern char _initrd_start[]; 28 extern char _initrd_end[]; 29 extern char _dtb_start[]; 30 extern char _dtb_end[]; 31 32 static struct gunzip_state gzstate; 33 34 struct addr_range { 35 void *addr; 36 unsigned long size; 37 }; 38 39 typedef void (*kernel_entry_t)(unsigned long, unsigned long, void *); 40 41 #undef DEBUG 42 43 static struct addr_range prep_kernel(void) 44 { 45 char elfheader[256]; 46 void *vmlinuz_addr = _vmlinux_start; 47 unsigned long vmlinuz_size = _vmlinux_end - _vmlinux_start; 48 void *addr = 0; 49 struct elf_info ei; 50 int len; 51 52 /* gunzip the ELF header of the kernel */ 53 gunzip_start(&gzstate, vmlinuz_addr, vmlinuz_size); 54 gunzip_exactly(&gzstate, elfheader, sizeof(elfheader)); 55 56 if (!parse_elf64(elfheader, &ei) && !parse_elf32(elfheader, &ei)) 57 fatal("Error: not a valid PPC32 or PPC64 ELF file!\n\r"); 58 59 if (platform_ops.image_hdr) 60 platform_ops.image_hdr(elfheader); 61 62 /* We need to alloc the memsize: gzip will expand the kernel 63 * text/data, then possible rubbish we don't care about. But 64 * the kernel bss must be claimed (it will be zero'd by the 65 * kernel itself) 66 */ 67 printf("Allocating 0x%lx bytes for kernel ...\n\r", ei.memsize); 68 69 if (platform_ops.vmlinux_alloc) { 70 addr = platform_ops.vmlinux_alloc(ei.memsize); 71 } else { 72 if ((unsigned long)_start < ei.memsize) 73 fatal("Insufficient memory for kernel at address 0!" 74 " (_start=%p)\n\r", _start); 75 } 76 77 /* Finally, gunzip the kernel */ 78 printf("gunzipping (0x%p <- 0x%p:0x%p)...", addr, 79 vmlinuz_addr, vmlinuz_addr+vmlinuz_size); 80 /* discard up to the actual load data */ 81 gunzip_discard(&gzstate, ei.elfoffset - sizeof(elfheader)); 82 len = gunzip_finish(&gzstate, addr, ei.loadsize); 83 if (len != ei.loadsize) 84 fatal("ran out of data! only got 0x%x of 0x%lx bytes.\n\r", 85 len, ei.loadsize); 86 printf("done 0x%x bytes\n\r", len); 87 88 flush_cache(addr, ei.loadsize); 89 90 return (struct addr_range){addr, ei.memsize}; 91 } 92 93 static struct addr_range prep_initrd(struct addr_range vmlinux, void *chosen, 94 unsigned long initrd_addr, 95 unsigned long initrd_size) 96 { 97 /* If we have an image attached to us, it overrides anything 98 * supplied by the loader. */ 99 if (_initrd_end > _initrd_start) { 100 printf("Attached initrd image at 0x%p-0x%p\n\r", 101 _initrd_start, _initrd_end); 102 initrd_addr = (unsigned long)_initrd_start; 103 initrd_size = _initrd_end - _initrd_start; 104 } else if (initrd_size > 0) { 105 printf("Using loader supplied ramdisk at 0x%lx-0x%lx\n\r", 106 initrd_addr, initrd_addr + initrd_size); 107 } 108 109 /* If there's no initrd at all, we're done */ 110 if (! initrd_size) 111 return (struct addr_range){0, 0}; 112 113 /* 114 * If the initrd is too low it will be clobbered when the 115 * kernel relocates to its final location. In this case, 116 * allocate a safer place and move it. 117 */ 118 if (initrd_addr < vmlinux.size) { 119 void *old_addr = (void *)initrd_addr; 120 121 printf("Allocating 0x%lx bytes for initrd ...\n\r", 122 initrd_size); 123 initrd_addr = (unsigned long)malloc(initrd_size); 124 if (! initrd_addr) 125 fatal("Can't allocate memory for initial " 126 "ramdisk !\n\r"); 127 printf("Relocating initrd 0x%lx <- 0x%p (0x%lx bytes)\n\r", 128 initrd_addr, old_addr, initrd_size); 129 memmove((void *)initrd_addr, old_addr, initrd_size); 130 } 131 132 printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd_addr)); 133 134 /* Tell the kernel initrd address via device tree */ 135 setprop_val(chosen, "linux,initrd-start", (u32)(initrd_addr)); 136 setprop_val(chosen, "linux,initrd-end", (u32)(initrd_addr+initrd_size)); 137 138 return (struct addr_range){(void *)initrd_addr, initrd_size}; 139 } 140 141 /* A buffer that may be edited by tools operating on a zImage binary so as to 142 * edit the command line passed to vmlinux (by setting /chosen/bootargs). 143 * The buffer is put in it's own section so that tools may locate it easier. 144 */ 145 static char cmdline[COMMAND_LINE_SIZE] 146 __attribute__((__section__("__builtin_cmdline"))); 147 148 static void prep_cmdline(void *chosen) 149 { 150 if (cmdline[0] == '\0') 151 getprop(chosen, "bootargs", cmdline, COMMAND_LINE_SIZE-1); 152 153 printf("\n\rLinux/PowerPC load: %s", cmdline); 154 /* If possible, edit the command line */ 155 if (console_ops.edit_cmdline) 156 console_ops.edit_cmdline(cmdline, COMMAND_LINE_SIZE); 157 printf("\n\r"); 158 159 /* Put the command line back into the devtree for the kernel */ 160 setprop_str(chosen, "bootargs", cmdline); 161 } 162 163 struct platform_ops platform_ops; 164 struct dt_ops dt_ops; 165 struct console_ops console_ops; 166 struct loader_info loader_info; 167 168 void start(void) 169 { 170 struct addr_range vmlinux, initrd; 171 kernel_entry_t kentry; 172 unsigned long ft_addr = 0; 173 void *chosen; 174 175 /* Do this first, because malloc() could clobber the loader's 176 * command line. Only use the loader command line if a 177 * built-in command line wasn't set by an external tool */ 178 if ((loader_info.cmdline_len > 0) && (cmdline[0] == '\0')) 179 memmove(cmdline, loader_info.cmdline, 180 min(loader_info.cmdline_len, COMMAND_LINE_SIZE-1)); 181 182 if (console_ops.open && (console_ops.open() < 0)) 183 exit(); 184 if (platform_ops.fixups) 185 platform_ops.fixups(); 186 187 printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r", 188 _start, get_sp()); 189 190 /* Ensure that the device tree has a /chosen node */ 191 chosen = finddevice("/chosen"); 192 if (!chosen) 193 chosen = create_node(NULL, "chosen"); 194 195 vmlinux = prep_kernel(); 196 initrd = prep_initrd(vmlinux, chosen, 197 loader_info.initrd_addr, loader_info.initrd_size); 198 prep_cmdline(chosen); 199 200 printf("Finalizing device tree..."); 201 if (dt_ops.finalize) 202 ft_addr = dt_ops.finalize(); 203 if (ft_addr) 204 printf(" flat tree at 0x%lx\n\r", ft_addr); 205 else 206 printf(" using OF tree (promptr=%p)\n\r", loader_info.promptr); 207 208 if (console_ops.close) 209 console_ops.close(); 210 211 kentry = (kernel_entry_t) vmlinux.addr; 212 if (ft_addr) 213 kentry(ft_addr, 0, NULL); 214 else 215 kentry((unsigned long)initrd.addr, initrd.size, 216 loader_info.promptr); 217 218 /* console closed so printf in fatal below may not work */ 219 fatal("Error: Linux kernel returned to zImage boot wrapper!\n\r"); 220 } 221