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