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 #undef DEBUG 40 41 static struct addr_range prep_kernel(void) 42 { 43 char elfheader[256]; 44 void *vmlinuz_addr = _vmlinux_start; 45 unsigned long vmlinuz_size = _vmlinux_end - _vmlinux_start; 46 void *addr = 0; 47 struct elf_info ei; 48 int len; 49 50 /* gunzip the ELF header of the kernel */ 51 gunzip_start(&gzstate, vmlinuz_addr, vmlinuz_size); 52 gunzip_exactly(&gzstate, elfheader, sizeof(elfheader)); 53 54 if (!parse_elf64(elfheader, &ei) && !parse_elf32(elfheader, &ei)) 55 fatal("Error: not a valid PPC32 or PPC64 ELF file!\n\r"); 56 57 if (platform_ops.image_hdr) 58 platform_ops.image_hdr(elfheader); 59 60 /* We need to alloc the memsize: gzip will expand the kernel 61 * text/data, then possible rubbish we don't care about. But 62 * the kernel bss must be claimed (it will be zero'd by the 63 * kernel itself) 64 */ 65 printf("Allocating 0x%lx bytes for kernel ...\n\r", ei.memsize); 66 67 if (platform_ops.vmlinux_alloc) { 68 addr = platform_ops.vmlinux_alloc(ei.memsize); 69 } else { 70 if ((unsigned long)_start < ei.memsize) 71 fatal("Insufficient memory for kernel at address 0!" 72 " (_start=%p)\n\r", _start); 73 } 74 75 /* Finally, gunzip the kernel */ 76 printf("gunzipping (0x%p <- 0x%p:0x%p)...", addr, 77 vmlinuz_addr, vmlinuz_addr+vmlinuz_size); 78 /* discard up to the actual load data */ 79 gunzip_discard(&gzstate, ei.elfoffset - sizeof(elfheader)); 80 len = gunzip_finish(&gzstate, addr, ei.loadsize); 81 if (len != ei.loadsize) 82 fatal("ran out of data! only got 0x%x of 0x%lx bytes.\n\r", 83 len, ei.loadsize); 84 printf("done 0x%x 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[COMMAND_LINE_SIZE] 144 __attribute__((__section__("__builtin_cmdline"))); 145 146 static void prep_cmdline(void *chosen) 147 { 148 if (cmdline[0] == '\0') 149 getprop(chosen, "bootargs", cmdline, COMMAND_LINE_SIZE-1); 150 151 printf("\n\rLinux/PowerPC load: %s", cmdline); 152 /* If possible, edit the command line */ 153 if (console_ops.edit_cmdline) 154 console_ops.edit_cmdline(cmdline, COMMAND_LINE_SIZE); 155 printf("\n\r"); 156 157 /* Put the command line back into the devtree for the kernel */ 158 setprop_str(chosen, "bootargs", cmdline); 159 } 160 161 struct platform_ops platform_ops; 162 struct dt_ops dt_ops; 163 struct console_ops console_ops; 164 struct loader_info loader_info; 165 166 void start(void) 167 { 168 struct addr_range vmlinux, initrd; 169 kernel_entry_t kentry; 170 unsigned long ft_addr = 0; 171 void *chosen; 172 173 /* Do this first, because malloc() could clobber the loader's 174 * command line. Only use the loader command line if a 175 * built-in command line wasn't set by an external tool */ 176 if ((loader_info.cmdline_len > 0) && (cmdline[0] == '\0')) 177 memmove(cmdline, loader_info.cmdline, 178 min(loader_info.cmdline_len, COMMAND_LINE_SIZE-1)); 179 180 if (console_ops.open && (console_ops.open() < 0)) 181 exit(); 182 if (platform_ops.fixups) 183 platform_ops.fixups(); 184 185 printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r", 186 _start, get_sp()); 187 188 /* Ensure that the device tree has a /chosen node */ 189 chosen = finddevice("/chosen"); 190 if (!chosen) 191 chosen = create_node(NULL, "chosen"); 192 193 vmlinux = prep_kernel(); 194 initrd = prep_initrd(vmlinux, chosen, 195 loader_info.initrd_addr, loader_info.initrd_size); 196 prep_cmdline(chosen); 197 198 printf("Finalizing device tree..."); 199 if (dt_ops.finalize) 200 ft_addr = dt_ops.finalize(); 201 if (ft_addr) 202 printf(" flat tree at 0x%lx\n\r", ft_addr); 203 else 204 printf(" using OF tree (promptr=%p)\n\r", loader_info.promptr); 205 206 if (console_ops.close) 207 console_ops.close(); 208 209 kentry = (kernel_entry_t) vmlinux.addr; 210 if (ft_addr) 211 kentry(ft_addr, 0, NULL); 212 else 213 kentry((unsigned long)initrd.addr, initrd.size, 214 loader_info.promptr); 215 216 /* console closed so printf in fatal below may not work */ 217 fatal("Error: Linux kernel returned to zImage boot wrapper!\n\r"); 218 } 219