arch/ppc64/boot/main.c

   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 "prom.h"
  18 #include "zlib.h"
  19
  20 static void gunzip(void *, int, unsigned char *, int *);
  21 extern void flush_cache(void *, unsigned long);
  22
  23
  24 /* Value picked to match that used by yaboot */
  25 #define PROG_START      0x01400000
  26 #define RAM_END         (512<<20) // Fixme: use OF */
  27 #define ONE_MB          0x100000
  28
  29 static char *avail_ram;
  30 static char *begin_avail, *end_avail;
  31 static char *avail_high;
  32 static unsigned int heap_use;
  33 static unsigned int heap_max;
  34
  35 extern char _start[];
  36 extern char _end[];
  37 extern char _vmlinux_start[];
  38 extern char _vmlinux_end[];
  39 extern char _initrd_start[];
  40 extern char _initrd_end[];
  41 extern unsigned long vmlinux_filesize;
  42 extern unsigned long vmlinux_memsize;
  43
  44 struct addr_range {
  45         unsigned long addr;
  46         unsigned long size;
  47         unsigned long memsize;
  48 };
  49 static struct addr_range vmlinux = {0, 0, 0};
  50 static struct addr_range vmlinuz = {0, 0, 0};
  51 static struct addr_range initrd  = {0, 0, 0};
  52
  53 static char scratch[128<<10];   /* 128kB of scratch space for gunzip */
  54
  55 typedef void (*kernel_entry_t)( unsigned long,
  56                                 unsigned long,
  57                                 void *,
  58                                 void *);
  59
  60
  61 #undef DEBUG
  62
  63 static unsigned long claim_base;
  64
  65 static unsigned long try_claim(unsigned long size)
  66 {
  67         unsigned long addr = 0;
  68
  69         for(; claim_base < RAM_END; claim_base += ONE_MB) {
  70 #ifdef DEBUG
  71                 printf("    trying: 0x%08lx\n\r", claim_base);
  72 #endif
  73                 addr = (unsigned long)claim(claim_base, size, 0);
  74                 if ((void *)addr != (void *)-1)
  75                         break;
  76         }
  77         if (addr == 0)
  78                 return 0;
  79         claim_base = PAGE_ALIGN(claim_base + size);
  80         return addr;
  81 }
  82
  83 void start(unsigned long a1, unsigned long a2, void *promptr)
  84 {
  85         unsigned long i;
  86         kernel_entry_t kernel_entry;
  87         Elf64_Ehdr *elf64;
  88         Elf64_Phdr *elf64ph;
  89
  90         prom = (int (*)(void *)) promptr;
  91         chosen_handle = finddevice("/chosen");
  92         if (chosen_handle == (void *) -1)
  93                 exit();
  94         if (getprop(chosen_handle, "stdout", &stdout, sizeof(stdout)) != 4)
  95                 exit();
  96         stderr = stdout;
  97         if (getprop(chosen_handle, "stdin", &stdin, sizeof(stdin)) != 4)
  98                 exit();
  99
 100         printf("\n\rzImage starting: loaded at 0x%lx\n\r", (unsigned long) _start);
 101
 102         /*
 103          * The first available claim_base must be above the end of the
 104          * the loaded kernel wrapper file (_start to _end includes the
 105          * initrd image if it is present) and rounded up to a nice
 106          * 1 MB boundary for good measure.
 107          */
 108
 109         claim_base = _ALIGN_UP((unsigned long)_end, ONE_MB);
 110
 111 #if defined(PROG_START)
 112         /*
 113          * Maintain a "magic" minimum address. This keeps some older
 114          * firmware platforms running.
 115          */
 116
 117         if (claim_base < PROG_START)
 118                 claim_base = PROG_START;
 119 #endif
 120
 121         /*
 122          * Now we try to claim some memory for the kernel itself
 123          * our "vmlinux_memsize" is the memory footprint in RAM, _HOWEVER_, what
 124          * our Makefile stuffs in is an image containing all sort of junk including
 125          * an ELF header. We need to do some calculations here to find the right
 126          * size... In practice we add 1Mb, that is enough, but we should really
 127          * consider fixing the Makefile to put a _raw_ kernel in there !
 128          */
 129         vmlinux_memsize += ONE_MB;
 130         printf("Allocating 0x%lx bytes for kernel ...\n\r", vmlinux_memsize);
 131         vmlinux.addr = try_claim(vmlinux_memsize);
 132         if (vmlinux.addr == 0) {
 133                 printf("Can't allocate memory for kernel image !\n\r");
 134                 exit();
 135         }
 136         vmlinuz.addr = (unsigned long)_vmlinux_start;
 137         vmlinuz.size = (unsigned long)(_vmlinux_end - _vmlinux_start);
 138         vmlinux.size = PAGE_ALIGN(vmlinux_filesize);
 139         vmlinux.memsize = vmlinux_memsize;
 140
 141         /*
 142          * Now we try to claim memory for the initrd (and copy it there)
 143          */
 144         initrd.size = (unsigned long)(_initrd_end - _initrd_start);
 145         initrd.memsize = initrd.size;
 146         if ( initrd.size > 0 ) {
 147                 printf("Allocating 0x%lx bytes for initrd ...\n\r", initrd.size);
 148                 initrd.addr = try_claim(initrd.size);
 149                 if (initrd.addr == 0) {
 150                         printf("Can't allocate memory for initial ramdisk !\n\r");
 151                         exit();
 152                 }
 153                 a1 = initrd.addr;
 154                 a2 = initrd.size;
 155                 printf("initial ramdisk moving 0x%lx <- 0x%lx (0x%lx bytes)\n\r",
 156                        initrd.addr, (unsigned long)_initrd_start, initrd.size);
 157                 memmove((void *)initrd.addr, (void *)_initrd_start, initrd.size);
 158                 printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd.addr));
 159         }
 160
 161         /* Eventually gunzip the kernel */
 162         if (*(unsigned short *)vmlinuz.addr == 0x1f8b) {
 163                 int len;
 164                 avail_ram = scratch;
 165                 begin_avail = avail_high = avail_ram;
 166                 end_avail = scratch + sizeof(scratch);
 167                 printf("gunzipping (0x%lx <- 0x%lx:0x%0lx)...",
 168                        vmlinux.addr, vmlinuz.addr, vmlinuz.addr+vmlinuz.size);
 169                 len = vmlinuz.size;
 170                 gunzip((void *)vmlinux.addr, vmlinux.size,
 171                         (unsigned char *)vmlinuz.addr, &len);
 172                 printf("done 0x%lx bytes\n\r", len);
 173                 printf("0x%x bytes of heap consumed, max in use 0x%x\n\r",
 174                        (unsigned)(avail_high - begin_avail), heap_max);
 175         } else {
 176                 memmove((void *)vmlinux.addr,(void *)vmlinuz.addr,vmlinuz.size);
 177         }
 178
 179         /* Skip over the ELF header */
 180         elf64 = (Elf64_Ehdr *)vmlinux.addr;
 181         if ( elf64->e_ident[EI_MAG0]  != ELFMAG0        ||
 182              elf64->e_ident[EI_MAG1]  != ELFMAG1        ||
 183              elf64->e_ident[EI_MAG2]  != ELFMAG2        ||
 184              elf64->e_ident[EI_MAG3]  != ELFMAG3        ||
 185              elf64->e_ident[EI_CLASS] != ELFCLASS64     ||
 186              elf64->e_ident[EI_DATA]  != ELFDATA2MSB    ||
 187              elf64->e_type            != ET_EXEC        ||
 188              elf64->e_machine         != EM_PPC64 )
 189         {
 190                 printf("Error: not a valid PPC64 ELF file!\n\r");
 191                 exit();
 192         }
 193
 194         elf64ph = (Elf64_Phdr *)((unsigned long)elf64 +
 195                                 (unsigned long)elf64->e_phoff);
 196         for(i=0; i < (unsigned int)elf64->e_phnum ;i++,elf64ph++) {
 197                 if (elf64ph->p_type == PT_LOAD && elf64ph->p_offset != 0)
 198                         break;
 199         }
 200 #ifdef DEBUG
 201         printf("... skipping 0x%lx bytes of ELF header\n\r",
 202                         (unsigned long)elf64ph->p_offset);
 203 #endif
 204         vmlinux.addr += (unsigned long)elf64ph->p_offset;
 205         vmlinux.size -= (unsigned long)elf64ph->p_offset;
 206
 207         flush_cache((void *)vmlinux.addr, vmlinux.size);
 208
 209         kernel_entry = (kernel_entry_t)vmlinux.addr;
 210 #ifdef DEBUG
 211         printf( "kernel:\n\r"
 212                 "        entry addr = 0x%lx\n\r"
 213                 "        a1         = 0x%lx,\n\r"
 214                 "        a2         = 0x%lx,\n\r"
 215                 "        prom       = 0x%lx,\n\r"
 216                 "        bi_recs    = 0x%lx,\n\r",
 217                 (unsigned long)kernel_entry, a1, a2,
 218                 (unsigned long)prom, NULL);
 219 #endif
 220
 221         kernel_entry( a1, a2, prom, NULL );
 222
 223         printf("Error: Linux kernel returned to zImage bootloader!\n\r");
 224
 225         exit();
 226 }
 227
 228 struct memchunk {
 229         unsigned int size;
 230         unsigned int pad;
 231         struct memchunk *next;
 232 };
 233
 234 static struct memchunk *freechunks;
 235
 236 void *zalloc(void *x, unsigned items, unsigned size)
 237 {
 238         void *p;
 239         struct memchunk **mpp, *mp;
 240
 241         size *= items;
 242         size = _ALIGN(size, sizeof(struct memchunk));
 243         heap_use += size;
 244         if (heap_use > heap_max)
 245                 heap_max = heap_use;
 246         for (mpp = &freechunks; (mp = *mpp) != 0; mpp = &mp->next) {
 247                 if (mp->size == size) {
 248                         *mpp = mp->next;
 249                         return mp;
 250                 }
 251         }
 252         p = avail_ram;
 253         avail_ram += size;
 254         if (avail_ram > avail_high)
 255                 avail_high = avail_ram;
 256         if (avail_ram > end_avail) {
 257                 printf("oops... out of memory\n\r");
 258                 pause();
 259         }
 260         return p;
 261 }
 262
 263 void zfree(void *x, void *addr, unsigned nb)
 264 {
 265         struct memchunk *mp = addr;
 266
 267         nb = _ALIGN(nb, sizeof(struct memchunk));
 268         heap_use -= nb;
 269         if (avail_ram == addr + nb) {
 270                 avail_ram = addr;
 271                 return;
 272         }
 273         mp->size = nb;
 274         mp->next = freechunks;
 275         freechunks = mp;
 276 }
 277
 278 #define HEAD_CRC        2
 279 #define EXTRA_FIELD     4
 280 #define ORIG_NAME       8
 281 #define COMMENT         0x10
 282 #define RESERVED        0xe0
 283
 284 #define DEFLATED        8
 285
 286 static void gunzip(void *dst, int dstlen, unsigned char *src, int *lenp)
 287 {
 288         z_stream s;
 289         int r, i, flags;
 290
 291         /* skip header */
 292         i = 10;
 293         flags = src[3];
 294         if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
 295                 printf("bad gzipped data\n\r");
 296                 exit();
 297         }
 298         if ((flags & EXTRA_FIELD) != 0)
 299                 i = 12 + src[10] + (src[11] << 8);
 300         if ((flags & ORIG_NAME) != 0)
 301                 while (src[i++] != 0)
 302                         ;
 303         if ((flags & COMMENT) != 0)
 304                 while (src[i++] != 0)
 305                         ;
 306         if ((flags & HEAD_CRC) != 0)
 307                 i += 2;
 308         if (i >= *lenp) {
 309                 printf("gunzip: ran out of data in header\n\r");
 310                 exit();
 311         }
 312
 313         s.zalloc = zalloc;
 314         s.zfree = zfree;
 315         r = inflateInit2(&s, -MAX_WBITS);
 316         if (r != Z_OK) {
 317                 printf("inflateInit2 returned %d\n\r", r);
 318                 exit();
 319         }
 320         s.next_in = src + i;
 321         s.avail_in = *lenp - i;
 322         s.next_out = dst;
 323         s.avail_out = dstlen;
 324         r = inflate(&s, Z_FINISH);
 325         if (r != Z_OK && r != Z_STREAM_END) {
 326                 printf("inflate returned %d msg: %s\n\r", r, s.msg);
 327                 exit();
 328         }
 329         *lenp = s.next_out - (unsigned char *) dst;
 330         inflateEnd(&s);
 331 }
 332