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 "ppc32-types.h"
  12 #include "zlib.h"
  13 #include <linux/elf.h>
  14 #include <linux/string.h>
  15 #include <asm/processor.h>
  16 #include <asm/page.h>
  17
  18 extern void *finddevice(const char *);
  19 extern int getprop(void *, const char *, void *, int);
  20 extern void printf(const char *fmt, ...);
  21 extern int sprintf(char *buf, const char *fmt, ...);
  22 void gunzip(void *, int, unsigned char *, int *);
  23 void *claim(unsigned int, unsigned int, unsigned int);
  24 void flush_cache(void *, unsigned long);
  25 void pause(void);
  26 extern void exit(void);
  27
  28 unsigned long strlen(const char *s);
  29 void *memmove(void *dest, const void *src, unsigned long n);
  30 void *memcpy(void *dest, const void *src, unsigned long n);
  31
  32 /* Value picked to match that used by yaboot */
  33 #define PROG_START      0x01400000
  34 #define RAM_END         (256<<20) // Fixme: use OF */
  35
  36 char *avail_ram;
  37 char *begin_avail, *end_avail;
  38 char *avail_high;
  39 unsigned int heap_use;
  40 unsigned int heap_max;
  41
  42 extern char _start[];
  43 extern char _vmlinux_start[];
  44 extern char _vmlinux_end[];
  45 extern char _initrd_start[];
  46 extern char _initrd_end[];
  47 extern unsigned long vmlinux_filesize;
  48 extern unsigned long vmlinux_memsize;
  49
  50 struct addr_range {
  51         unsigned long addr;
  52         unsigned long size;
  53         unsigned long memsize;
  54 };
  55 struct addr_range vmlinux = {0, 0, 0};
  56 struct addr_range vmlinuz = {0, 0, 0};
  57 struct addr_range initrd  = {0, 0, 0};
  58
  59 static char scratch[128<<10];   /* 128kB of scratch space for gunzip */
  60
  61 typedef void (*kernel_entry_t)( unsigned long,
  62                                 unsigned long,
  63                                 void *,
  64                                 void *);
  65
  66
  67 int (*prom)(void *);
  68
  69 void *chosen_handle;
  70 void *stdin;
  71 void *stdout;
  72 void *stderr;
  73
  74 #undef DEBUG
  75
  76 static unsigned long claim_base = PROG_START;
  77
  78 static unsigned long try_claim(unsigned long size)
  79 {
  80         unsigned long addr = 0;
  81
  82         for(; claim_base < RAM_END; claim_base += 0x100000) {
  83 #ifdef DEBUG
  84                 printf("    trying: 0x%08lx\n\r", claim_base);
  85 #endif
  86                 addr = (unsigned long)claim(claim_base, size, 0);
  87                 if ((void *)addr != (void *)-1)
  88                         break;
  89         }
  90         if (addr == 0)
  91                 return 0;
  92         claim_base = PAGE_ALIGN(claim_base + size);
  93         return addr;
  94 }
  95
  96 void start(unsigned long a1, unsigned long a2, void *promptr)
  97 {
  98         unsigned long i;
  99         kernel_entry_t kernel_entry;
 100         Elf64_Ehdr *elf64;
 101         Elf64_Phdr *elf64ph;
 102
 103         prom = (int (*)(void *)) promptr;
 104         chosen_handle = finddevice("/chosen");
 105         if (chosen_handle == (void *) -1)
 106                 exit();
 107         if (getprop(chosen_handle, "stdout", &stdout, sizeof(stdout)) != 4)
 108                 exit();
 109         stderr = stdout;
 110         if (getprop(chosen_handle, "stdin", &stdin, sizeof(stdin)) != 4)
 111                 exit();
 112
 113         printf("\n\rzImage starting: loaded at 0x%x\n\r", (unsigned)_start);
 114
 115         /*
 116          * Now we try to claim some memory for the kernel itself
 117          * our "vmlinux_memsize" is the memory footprint in RAM, _HOWEVER_, what
 118          * our Makefile stuffs in is an image containing all sort of junk including
 119          * an ELF header. We need to do some calculations here to find the right
 120          * size... In practice we add 1Mb, that is enough, but we should really
 121          * consider fixing the Makefile to put a _raw_ kernel in there !
 122          */
 123         vmlinux_memsize += 0x100000;
 124         printf("Allocating 0x%lx bytes for kernel ...\n\r", vmlinux_memsize);
 125         vmlinux.addr = try_claim(vmlinux_memsize);
 126         if (vmlinux.addr == 0) {
 127                 printf("Can't allocate memory for kernel image !\n\r");
 128                 exit();
 129         }
 130         vmlinuz.addr = (unsigned long)_vmlinux_start;
 131         vmlinuz.size = (unsigned long)(_vmlinux_end - _vmlinux_start);
 132         vmlinux.size = PAGE_ALIGN(vmlinux_filesize);
 133         vmlinux.memsize = vmlinux_memsize;
 134
 135         /*
 136          * Now we try to claim memory for the initrd (and copy it there)
 137          */
 138         initrd.size = (unsigned long)(_initrd_end - _initrd_start);
 139         initrd.memsize = initrd.size;
 140         if ( initrd.size > 0 ) {
 141                 printf("Allocating 0x%lx bytes for initrd ...\n\r", initrd.size);
 142                 initrd.addr = try_claim(initrd.size);
 143                 if (initrd.addr == 0) {
 144                         printf("Can't allocate memory for initial ramdisk !\n\r");
 145                         exit();
 146                 }
 147                 a1 = initrd.addr;
 148                 a2 = initrd.size;
 149                 printf("initial ramdisk moving 0x%lx <- 0x%lx (%lx bytes)\n\r",
 150                        initrd.addr, (unsigned long)_initrd_start, initrd.size);
 151                 memmove((void *)initrd.addr, (void *)_initrd_start, initrd.size);
 152                 printf("initrd head: 0x%lx\n\r", *((u32 *)initrd.addr));
 153         }
 154
 155         /* Eventually gunzip the kernel */
 156         if (*(unsigned short *)vmlinuz.addr == 0x1f8b) {
 157                 int len;
 158                 avail_ram = scratch;
 159                 begin_avail = avail_high = avail_ram;
 160                 end_avail = scratch + sizeof(scratch);
 161                 printf("gunzipping (0x%lx <- 0x%lx:0x%0lx)...",
 162                        vmlinux.addr, vmlinuz.addr, vmlinuz.addr+vmlinuz.size);
 163                 len = vmlinuz.size;
 164                 gunzip((void *)vmlinux.addr, vmlinux.size,
 165                         (unsigned char *)vmlinuz.addr, &len);
 166                 printf("done 0x%lx bytes\n\r", len);
 167                 printf("0x%x bytes of heap consumed, max in use 0x%x\n\r",
 168                        (unsigned)(avail_high - begin_avail), heap_max);
 169         } else {
 170                 memmove((void *)vmlinux.addr,(void *)vmlinuz.addr,vmlinuz.size);
 171         }
 172
 173         /* Skip over the ELF header */
 174         elf64 = (Elf64_Ehdr *)vmlinux.addr;
 175         if ( elf64->e_ident[EI_MAG0]  != ELFMAG0        ||
 176              elf64->e_ident[EI_MAG1]  != ELFMAG1        ||
 177              elf64->e_ident[EI_MAG2]  != ELFMAG2        ||
 178              elf64->e_ident[EI_MAG3]  != ELFMAG3        ||
 179              elf64->e_ident[EI_CLASS] != ELFCLASS64     ||
 180              elf64->e_ident[EI_DATA]  != ELFDATA2MSB    ||
 181              elf64->e_type            != ET_EXEC        ||
 182              elf64->e_machine         != EM_PPC64 )
 183         {
 184                 printf("Error: not a valid PPC64 ELF file!\n\r");
 185                 exit();
 186         }
 187
 188         elf64ph = (Elf64_Phdr *)((unsigned long)elf64 +
 189                                 (unsigned long)elf64->e_phoff);
 190         for(i=0; i < (unsigned int)elf64->e_phnum ;i++,elf64ph++) {
 191                 if (elf64ph->p_type == PT_LOAD && elf64ph->p_offset != 0)
 192                         break;
 193         }
 194 #ifdef DEBUG
 195         printf("... skipping 0x%lx bytes of ELF header\n\r",
 196                         (unsigned long)elf64ph->p_offset);
 197 #endif
 198         vmlinux.addr += (unsigned long)elf64ph->p_offset;
 199         vmlinux.size -= (unsigned long)elf64ph->p_offset;
 200
 201         flush_cache((void *)vmlinux.addr, vmlinux.size);
 202
 203         if (a1)
 204                 printf("initrd head: 0x%lx\n\r", *((u32 *)initrd.addr));
 205
 206         kernel_entry = (kernel_entry_t)vmlinux.addr;
 207 #ifdef DEBUG
 208         printf( "kernel:\n\r"
 209                 "        entry addr = 0x%lx\n\r"
 210                 "        a1         = 0x%lx,\n\r"
 211                 "        a2         = 0x%lx,\n\r"
 212                 "        prom       = 0x%lx,\n\r"
 213                 "        bi_recs    = 0x%lx,\n\r",
 214                 (unsigned long)kernel_entry, a1, a2,
 215                 (unsigned long)prom, NULL);
 216 #endif
 217
 218         kernel_entry( a1, a2, prom, NULL );
 219
 220         printf("Error: Linux kernel returned to zImage bootloader!\n\r");
 221
 222         exit();
 223 }
 224
 225 struct memchunk {
 226         unsigned int size;
 227         unsigned int pad;
 228         struct memchunk *next;
 229 };
 230
 231 static struct memchunk *freechunks;
 232
 233 void *zalloc(void *x, unsigned items, unsigned size)
 234 {
 235         void *p;
 236         struct memchunk **mpp, *mp;
 237
 238         size *= items;
 239         size = _ALIGN(size, sizeof(struct memchunk));
 240         heap_use += size;
 241         if (heap_use > heap_max)
 242                 heap_max = heap_use;
 243         for (mpp = &freechunks; (mp = *mpp) != 0; mpp = &mp->next) {
 244                 if (mp->size == size) {
 245                         *mpp = mp->next;
 246                         return mp;
 247                 }
 248         }
 249         p = avail_ram;
 250         avail_ram += size;
 251         if (avail_ram > avail_high)
 252                 avail_high = avail_ram;
 253         if (avail_ram > end_avail) {
 254                 printf("oops... out of memory\n\r");
 255                 pause();
 256         }
 257         return p;
 258 }
 259
 260 void zfree(void *x, void *addr, unsigned nb)
 261 {
 262         struct memchunk *mp = addr;
 263
 264         nb = _ALIGN(nb, sizeof(struct memchunk));
 265         heap_use -= nb;
 266         if (avail_ram == addr + nb) {
 267                 avail_ram = addr;
 268                 return;
 269         }
 270         mp->size = nb;
 271         mp->next = freechunks;
 272         freechunks = mp;
 273 }
 274
 275 #define HEAD_CRC        2
 276 #define EXTRA_FIELD     4
 277 #define ORIG_NAME       8
 278 #define COMMENT         0x10
 279 #define RESERVED        0xe0
 280
 281 #define DEFLATED        8
 282
 283 void gunzip(void *dst, int dstlen, unsigned char *src, int *lenp)
 284 {
 285         z_stream s;
 286         int r, i, flags;
 287
 288         /* skip header */
 289         i = 10;
 290         flags = src[3];
 291         if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
 292                 printf("bad gzipped data\n\r");
 293                 exit();
 294         }
 295         if ((flags & EXTRA_FIELD) != 0)
 296                 i = 12 + src[10] + (src[11] << 8);
 297         if ((flags & ORIG_NAME) != 0)
 298                 while (src[i++] != 0)
 299                         ;
 300         if ((flags & COMMENT) != 0)
 301                 while (src[i++] != 0)
 302                         ;
 303         if ((flags & HEAD_CRC) != 0)
 304                 i += 2;
 305         if (i >= *lenp) {
 306                 printf("gunzip: ran out of data in header\n\r");
 307                 exit();
 308         }
 309
 310         s.zalloc = zalloc;
 311         s.zfree = zfree;
 312         r = inflateInit2(&s, -MAX_WBITS);
 313         if (r != Z_OK) {
 314                 printf("inflateInit2 returned %d\n\r", r);
 315                 exit();
 316         }
 317         s.next_in = src + i;
 318         s.avail_in = *lenp - i;
 319         s.next_out = dst;
 320         s.avail_out = dstlen;
 321         r = inflate(&s, Z_FINISH);
 322         if (r != Z_OK && r != Z_STREAM_END) {
 323                 printf("inflate returned %d msg: %s\n\r", r, s.msg);
 324                 exit();
 325         }
 326         *lenp = s.next_out - (unsigned char *) dst;
 327         inflateEnd(&s);
 328 }
 329