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 printk(char *fmt, ...);
  21 extern void printf(const char *fmt, ...);
  22 extern int sprintf(char *buf, const char *fmt, ...);
  23 void gunzip(void *, int, unsigned char *, int *);
  24 void *claim(unsigned int, unsigned int, unsigned int);
  25 void flush_cache(void *, unsigned long);
  26 void pause(void);
  27 extern void exit(void);
  28
  29 unsigned long strlen(const char *s);
  30 void *memmove(void *dest, const void *src, unsigned long n);
  31 void *memcpy(void *dest, const void *src, unsigned long n);
  32
  33 /* Value picked to match that used by yaboot */
  34 #define PROG_START      0x01400000
  35 #define RAM_END         (256<<20) // Fixme: use OF */
  36
  37 char *avail_ram;
  38 char *begin_avail, *end_avail;
  39 char *avail_high;
  40 unsigned int heap_use;
  41 unsigned int heap_max;
  42
  43 extern char _start[];
  44 extern char _vmlinux_start[];
  45 extern char _vmlinux_end[];
  46 extern char _initrd_start[];
  47 extern char _initrd_end[];
  48 extern unsigned long vmlinux_filesize;
  49 extern unsigned long vmlinux_memsize;
  50
  51 struct addr_range {
  52         unsigned long addr;
  53         unsigned long size;
  54         unsigned long memsize;
  55 };
  56 struct addr_range vmlinux = {0, 0, 0};
  57 struct addr_range vmlinuz = {0, 0, 0};
  58 struct addr_range initrd  = {0, 0, 0};
  59
  60 static char scratch[128<<10];   /* 128kB of scratch space for gunzip */
  61
  62 typedef void (*kernel_entry_t)( unsigned long,
  63                                 unsigned long,
  64                                 void *,
  65                                 void *);
  66
  67
  68 int (*prom)(void *);
  69
  70 void *chosen_handle;
  71 void *stdin;
  72 void *stdout;
  73 void *stderr;
  74
  75 #undef DEBUG
  76
  77 static unsigned long claim_base = PROG_START;
  78
  79 static unsigned long try_claim(unsigned long size)
  80 {
  81         unsigned long addr = 0;
  82
  83         for(; claim_base < RAM_END; claim_base += 0x100000) {
  84 #ifdef DEBUG
  85                 printf("    trying: 0x%08lx\n\r", claim_base);
  86 #endif
  87                 addr = (unsigned long)claim(claim_base, size, 0);
  88                 if ((void *)addr != (void *)-1)
  89                         break;
  90         }
  91         if (addr == 0)
  92                 return 0;
  93         claim_base = PAGE_ALIGN(claim_base + size);
  94         return addr;
  95 }
  96
  97 void start(unsigned long a1, unsigned long a2, void *promptr)
  98 {
  99         unsigned long i;
 100         kernel_entry_t kernel_entry;
 101         Elf64_Ehdr *elf64;
 102         Elf64_Phdr *elf64ph;
 103
 104         prom = (int (*)(void *)) promptr;
 105         chosen_handle = finddevice("/chosen");
 106         if (chosen_handle == (void *) -1)
 107                 exit();
 108         if (getprop(chosen_handle, "stdout", &stdout, sizeof(stdout)) != 4)
 109                 exit();
 110         stderr = stdout;
 111         if (getprop(chosen_handle, "stdin", &stdin, sizeof(stdin)) != 4)
 112                 exit();
 113
 114         printf("\n\rzImage starting: loaded at 0x%x\n\r", (unsigned)_start);
 115
 116         /*
 117          * Now we try to claim some memory for the kernel itself
 118          * our "vmlinux_memsize" is the memory footprint in RAM, _HOWEVER_, what
 119          * our Makefile stuffs in is an image containing all sort of junk including
 120          * an ELF header. We need to do some calculations here to find the right
 121          * size... In practice we add 1Mb, that is enough, but we should really
 122          * consider fixing the Makefile to put a _raw_ kernel in there !
 123          */
 124         vmlinux_memsize += 0x100000;
 125         printf("Allocating 0x%lx bytes for kernel ...\n\r", vmlinux_memsize);
 126         vmlinux.addr = try_claim(vmlinux_memsize);
 127         if (vmlinux.addr == 0) {
 128                 printf("Can't allocate memory for kernel image !\n\r");
 129                 exit();
 130         }
 131         vmlinuz.addr = (unsigned long)_vmlinux_start;
 132         vmlinuz.size = (unsigned long)(_vmlinux_end - _vmlinux_start);
 133         vmlinux.size = PAGE_ALIGN(vmlinux_filesize);
 134         vmlinux.memsize = vmlinux_memsize;
 135
 136         /*
 137          * Now we try to claim memory for the initrd (and copy it there)
 138          */
 139         initrd.size = (unsigned long)(_initrd_end - _initrd_start);
 140         initrd.memsize = initrd.size;
 141         if ( initrd.size > 0 ) {
 142                 printf("Allocating 0x%lx bytes for initrd ...\n\r", initrd.size);
 143                 initrd.addr = try_claim(initrd.size);
 144                 if (initrd.addr == 0) {
 145                         printf("Can't allocate memory for initial ramdisk !\n\r");
 146                         exit();
 147                 }
 148                 a1 = initrd.addr;
 149                 a2 = initrd.size;
 150                 printf("initial ramdisk moving 0x%lx <- 0x%lx (%lx bytes)\n\r",
 151                        initrd.addr, (unsigned long)_initrd_start, initrd.size);
 152                 memmove((void *)initrd.addr, (void *)_initrd_start, initrd.size);
 153                 printf("initrd head: 0x%lx\n\r", *((u32 *)initrd.addr));
 154         }
 155
 156         /* Eventually gunzip the kernel */
 157         if (*(unsigned short *)vmlinuz.addr == 0x1f8b) {
 158                 int len;
 159                 avail_ram = scratch;
 160                 begin_avail = avail_high = avail_ram;
 161                 end_avail = scratch + sizeof(scratch);
 162                 printf("gunzipping (0x%lx <- 0x%lx:0x%0lx)...",
 163                        vmlinux.addr, vmlinuz.addr, vmlinuz.addr+vmlinuz.size);
 164                 len = vmlinuz.size;
 165                 gunzip((void *)vmlinux.addr, vmlinux.size,
 166                         (unsigned char *)vmlinuz.addr, &len);
 167                 printf("done 0x%lx bytes\n\r", len);
 168                 printf("0x%x bytes of heap consumed, max in use 0x%x\n\r",
 169                        (unsigned)(avail_high - begin_avail), heap_max);
 170         } else {
 171                 memmove((void *)vmlinux.addr,(void *)vmlinuz.addr,vmlinuz.size);
 172         }
 173
 174         /* Skip over the ELF header */
 175         elf64 = (Elf64_Ehdr *)vmlinux.addr;
 176         if ( elf64->e_ident[EI_MAG0]  != ELFMAG0        ||
 177              elf64->e_ident[EI_MAG1]  != ELFMAG1        ||
 178              elf64->e_ident[EI_MAG2]  != ELFMAG2        ||
 179              elf64->e_ident[EI_MAG3]  != ELFMAG3        ||
 180              elf64->e_ident[EI_CLASS] != ELFCLASS64     ||
 181              elf64->e_ident[EI_DATA]  != ELFDATA2MSB    ||
 182              elf64->e_type            != ET_EXEC        ||
 183              elf64->e_machine         != EM_PPC64 )
 184         {
 185                 printf("Error: not a valid PPC64 ELF file!\n\r");
 186                 exit();
 187         }
 188
 189         elf64ph = (Elf64_Phdr *)((unsigned long)elf64 +
 190                                 (unsigned long)elf64->e_phoff);
 191         for(i=0; i < (unsigned int)elf64->e_phnum ;i++,elf64ph++) {
 192                 if (elf64ph->p_type == PT_LOAD && elf64ph->p_offset != 0)
 193                         break;
 194         }
 195 #ifdef DEBUG
 196         printf("... skipping 0x%lx bytes of ELF header\n\r",
 197                         (unsigned long)elf64ph->p_offset);
 198 #endif
 199         vmlinux.addr += (unsigned long)elf64ph->p_offset;
 200         vmlinux.size -= (unsigned long)elf64ph->p_offset;
 201
 202         flush_cache((void *)vmlinux.addr, vmlinux.size);
 203
 204         if (a1)
 205                 printf("initrd head: 0x%lx\n\r", *((u32 *)initrd.addr));
 206
 207         kernel_entry = (kernel_entry_t)vmlinux.addr;
 208 #ifdef DEBUG
 209         printf( "kernel:\n\r"
 210                 "        entry addr = 0x%lx\n\r"
 211                 "        a1         = 0x%lx,\n\r"
 212                 "        a2         = 0x%lx,\n\r"
 213                 "        prom       = 0x%lx,\n\r"
 214                 "        bi_recs    = 0x%lx,\n\r",
 215                 (unsigned long)kernel_entry, a1, a2,
 216                 (unsigned long)prom, NULL);
 217 #endif
 218
 219         kernel_entry( a1, a2, prom, NULL );
 220
 221         printf("Error: Linux kernel returned to zImage bootloader!\n\r");
 222
 223         exit();
 224 }
 225
 226 struct memchunk {
 227         unsigned int size;
 228         unsigned int pad;
 229         struct memchunk *next;
 230 };
 231
 232 static struct memchunk *freechunks;
 233
 234 void *zalloc(void *x, unsigned items, unsigned size)
 235 {
 236         void *p;
 237         struct memchunk **mpp, *mp;
 238
 239         size *= items;
 240         size = _ALIGN(size, sizeof(struct memchunk));
 241         heap_use += size;
 242         if (heap_use > heap_max)
 243                 heap_max = heap_use;
 244         for (mpp = &freechunks; (mp = *mpp) != 0; mpp = &mp->next) {
 245                 if (mp->size == size) {
 246                         *mpp = mp->next;
 247                         return mp;
 248                 }
 249         }
 250         p = avail_ram;
 251         avail_ram += size;
 252         if (avail_ram > avail_high)
 253                 avail_high = avail_ram;
 254         if (avail_ram > end_avail) {
 255                 printf("oops... out of memory\n\r");
 256                 pause();
 257         }
 258         return p;
 259 }
 260
 261 void zfree(void *x, void *addr, unsigned nb)
 262 {
 263         struct memchunk *mp = addr;
 264
 265         nb = _ALIGN(nb, sizeof(struct memchunk));
 266         heap_use -= nb;
 267         if (avail_ram == addr + nb) {
 268                 avail_ram = addr;
 269                 return;
 270         }
 271         mp->size = nb;
 272         mp->next = freechunks;
 273         freechunks = mp;
 274 }
 275
 276 #define HEAD_CRC        2
 277 #define EXTRA_FIELD     4
 278 #define ORIG_NAME       8
 279 #define COMMENT         0x10
 280 #define RESERVED        0xe0
 281
 282 #define DEFLATED        8
 283
 284 void gunzip(void *dst, int dstlen, unsigned char *src, int *lenp)
 285 {
 286         z_stream s;
 287         int r, i, flags;
 288
 289         /* skip header */
 290         i = 10;
 291         flags = src[3];
 292         if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
 293                 printf("bad gzipped data\n\r");
 294                 exit();
 295         }
 296         if ((flags & EXTRA_FIELD) != 0)
 297                 i = 12 + src[10] + (src[11] << 8);
 298         if ((flags & ORIG_NAME) != 0)
 299                 while (src[i++] != 0)
 300                         ;
 301         if ((flags & COMMENT) != 0)
 302                 while (src[i++] != 0)
 303                         ;
 304         if ((flags & HEAD_CRC) != 0)
 305                 i += 2;
 306         if (i >= *lenp) {
 307                 printf("gunzip: ran out of data in header\n\r");
 308                 exit();
 309         }
 310
 311         s.zalloc = zalloc;
 312         s.zfree = zfree;
 313         r = inflateInit2(&s, -MAX_WBITS);
 314         if (r != Z_OK) {
 315                 printf("inflateInit2 returned %d\n\r", r);
 316                 exit();
 317         }
 318         s.next_in = src + i;
 319         s.avail_in = *lenp - i;
 320         s.next_out = dst;
 321         s.avail_out = dstlen;
 322         r = inflate(&s, Z_FINISH);
 323         if (r != Z_OK && r != Z_STREAM_END) {
 324                 printf("inflate returned %d msg: %s\n\r", r, s.msg);
 325                 exit();
 326         }
 327         *lenp = s.next_out - (unsigned char *) dst;
 328         inflateEnd(&s);
 329 }
 330