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 #include <asm/bootinfo.h>
  18
  19 extern void *finddevice(const char *);
  20 extern int getprop(void *, const char *, void *, int);
  21 extern void printk(char *fmt, ...);
  22 extern void printf(const char *fmt, ...);
  23 extern int sprintf(char *buf, const char *fmt, ...);
  24 void gunzip(void *, int, unsigned char *, int *);
  25 void *claim(unsigned int, unsigned int, unsigned int);
  26 void flush_cache(void *, unsigned long);
  27 void pause(void);
  28 extern void exit(void);
  29
  30 unsigned long strlen(const char *s);
  31 void *memmove(void *dest, const void *src, unsigned long n);
  32 void *memcpy(void *dest, const void *src, unsigned long n);
  33
  34 /* Value picked to match that used by yaboot */
  35 #define PROG_START      0x01400000
  36 #define RAM_END         (256<<20) // Fixme: use OF */
  37
  38 char *avail_ram;
  39 char *begin_avail, *end_avail;
  40 char *avail_high;
  41 unsigned int heap_use;
  42 unsigned int heap_max;
  43
  44 extern char _start[];
  45 extern char _vmlinux_start[];
  46 extern char _vmlinux_end[];
  47 extern char _initrd_start[];
  48 extern char _initrd_end[];
  49 extern unsigned long vmlinux_filesize;
  50 extern unsigned long vmlinux_memsize;
  51
  52 struct addr_range {
  53         unsigned long addr;
  54         unsigned long size;
  55         unsigned long memsize;
  56 };
  57 struct addr_range vmlinux = {0, 0, 0};
  58 struct addr_range vmlinuz = {0, 0, 0};
  59 struct addr_range initrd  = {0, 0, 0};
  60
  61 static char scratch[128<<10];   /* 128kB of scratch space for gunzip */
  62
  63 typedef void (*kernel_entry_t)( unsigned long,
  64                                 unsigned long,
  65                                 void *,
  66                                 void *);
  67
  68
  69 int (*prom)(void *);
  70
  71 void *chosen_handle;
  72 void *stdin;
  73 void *stdout;
  74 void *stderr;
  75
  76 #undef DEBUG
  77
  78 static unsigned long claim_base = PROG_START;
  79
  80 static unsigned long try_claim(unsigned long size)
  81 {
  82         unsigned long addr = 0;
  83
  84         for(; claim_base < RAM_END; claim_base += 0x100000) {
  85 #ifdef DEBUG
  86                 printf("    trying: 0x%08lx\n\r", claim_base);
  87 #endif
  88                 addr = (unsigned long)claim(claim_base, size, 0);
  89                 if ((void *)addr != (void *)-1)
  90                         break;
  91         }
  92         if (addr == 0)
  93                 return 0;
  94         claim_base = PAGE_ALIGN(claim_base + size);
  95         return addr;
  96 }
  97
  98 void start(unsigned long a1, unsigned long a2, void *promptr)
  99 {
 100         unsigned long i;
 101         kernel_entry_t kernel_entry;
 102         Elf64_Ehdr *elf64;
 103         Elf64_Phdr *elf64ph;
 104
 105         prom = (int (*)(void *)) promptr;
 106         chosen_handle = finddevice("/chosen");
 107         if (chosen_handle == (void *) -1)
 108                 exit();
 109         if (getprop(chosen_handle, "stdout", &stdout, sizeof(stdout)) != 4)
 110                 exit();
 111         stderr = stdout;
 112         if (getprop(chosen_handle, "stdin", &stdin, sizeof(stdin)) != 4)
 113                 exit();
 114
 115         printf("\n\rzImage starting: loaded at 0x%x\n\r", (unsigned)_start);
 116
 117         /*
 118          * Now we try to claim some memory for the kernel itself
 119          * our "vmlinux_memsize" is the memory footprint in RAM, _HOWEVER_, what
 120          * our Makefile stuffs in is an image containing all sort of junk including
 121          * an ELF header. We need to do some calculations here to find the right
 122          * size... In practice we add 1Mb, that is enough, but we should really
 123          * consider fixing the Makefile to put a _raw_ kernel in there !
 124          */
 125         vmlinux_memsize += 0x100000;
 126         printf("Allocating 0x%lx bytes for kernel ...\n\r", vmlinux_memsize);
 127         vmlinux.addr = try_claim(vmlinux_memsize);
 128         if (vmlinux.addr == 0) {
 129                 printf("Can't allocate memory for kernel image !\n\r");
 130                 exit();
 131         }
 132         vmlinuz.addr = (unsigned long)_vmlinux_start;
 133         vmlinuz.size = (unsigned long)(_vmlinux_end - _vmlinux_start);
 134         vmlinux.size = PAGE_ALIGN(vmlinux_filesize);
 135         vmlinux.memsize = vmlinux_memsize;
 136
 137         /*
 138          * Now we try to claim memory for the initrd (and copy it there)
 139          */
 140         initrd.size = (unsigned long)(_initrd_end - _initrd_start);
 141         initrd.memsize = initrd.size;
 142         if ( initrd.size > 0 ) {
 143                 printf("Allocating 0x%lx bytes for initrd ...\n\r", initrd.size);
 144                 initrd.addr = try_claim(initrd.size);
 145                 if (initrd.addr == 0) {
 146                         printf("Can't allocate memory for initial ramdisk !\n\r");
 147                         exit();
 148                 }
 149                 a1 = initrd.addr;
 150                 a2 = initrd.size;
 151                 printf("initial ramdisk moving 0x%lx <- 0x%lx (%lx bytes)\n\r",
 152                        initrd.addr, (unsigned long)_initrd_start, initrd.size);
 153                 memmove((void *)initrd.addr, (void *)_initrd_start, initrd.size);
 154                 printf("initrd head: 0x%lx\n\r", *((u32 *)initrd.addr));
 155         }
 156
 157         /* Eventually gunzip the kernel */
 158         if (*(unsigned short *)vmlinuz.addr == 0x1f8b) {
 159                 int len;
 160                 avail_ram = scratch;
 161                 begin_avail = avail_high = avail_ram;
 162                 end_avail = scratch + sizeof(scratch);
 163                 printf("gunzipping (0x%lx <- 0x%lx:0x%0lx)...",
 164                        vmlinux.addr, vmlinuz.addr, vmlinuz.addr+vmlinuz.size);
 165                 len = vmlinuz.size;
 166                 gunzip((void *)vmlinux.addr, vmlinux.size,
 167                         (unsigned char *)vmlinuz.addr, &len);
 168                 printf("done 0x%lx bytes\n\r", len);
 169                 printf("0x%x bytes of heap consumed, max in use 0x%x\n\r",
 170                        (unsigned)(avail_high - begin_avail), heap_max);
 171         } else {
 172                 memmove((void *)vmlinux.addr,(void *)vmlinuz.addr,vmlinuz.size);
 173         }
 174
 175         /* Skip over the ELF header */
 176         elf64 = (Elf64_Ehdr *)vmlinux.addr;
 177         if ( elf64->e_ident[EI_MAG0]  != ELFMAG0        ||
 178              elf64->e_ident[EI_MAG1]  != ELFMAG1        ||
 179              elf64->e_ident[EI_MAG2]  != ELFMAG2        ||
 180              elf64->e_ident[EI_MAG3]  != ELFMAG3        ||
 181              elf64->e_ident[EI_CLASS] != ELFCLASS64     ||
 182              elf64->e_ident[EI_DATA]  != ELFDATA2MSB    ||
 183              elf64->e_type            != ET_EXEC        ||
 184              elf64->e_machine         != EM_PPC64 )
 185         {
 186                 printf("Error: not a valid PPC64 ELF file!\n\r");
 187                 exit();
 188         }
 189
 190         elf64ph = (Elf64_Phdr *)((unsigned long)elf64 +
 191                                 (unsigned long)elf64->e_phoff);
 192         for(i=0; i < (unsigned int)elf64->e_phnum ;i++,elf64ph++) {
 193                 if (elf64ph->p_type == PT_LOAD && elf64ph->p_offset != 0)
 194                         break;
 195         }
 196 #ifdef DEBUG
 197         printf("... skipping 0x%lx bytes of ELF header\n\r",
 198                         (unsigned long)elf64ph->p_offset);
 199 #endif
 200         vmlinux.addr += (unsigned long)elf64ph->p_offset;
 201         vmlinux.size -= (unsigned long)elf64ph->p_offset;
 202
 203         flush_cache((void *)vmlinux.addr, vmlinux.size);
 204
 205         if (a1)
 206                 printf("initrd head: 0x%lx\n\r", *((u32 *)initrd.addr));
 207
 208         kernel_entry = (kernel_entry_t)vmlinux.addr;
 209 #ifdef DEBUG
 210         printf( "kernel:\n\r"
 211                 "        entry addr = 0x%lx\n\r"
 212                 "        a1         = 0x%lx,\n\r"
 213                 "        a2         = 0x%lx,\n\r"
 214                 "        prom       = 0x%lx,\n\r"
 215                 "        bi_recs    = 0x%lx,\n\r",
 216                 (unsigned long)kernel_entry, a1, a2,
 217                 (unsigned long)prom, NULL);
 218 #endif
 219
 220         kernel_entry( a1, a2, prom, NULL );
 221
 222         printf("Error: Linux kernel returned to zImage bootloader!\n\r");
 223
 224         exit();
 225 }
 226
 227 struct memchunk {
 228         unsigned int size;
 229         unsigned int pad;
 230         struct memchunk *next;
 231 };
 232
 233 static struct memchunk *freechunks;
 234
 235 void *zalloc(void *x, unsigned items, unsigned size)
 236 {
 237         void *p;
 238         struct memchunk **mpp, *mp;
 239
 240         size *= items;
 241         size = _ALIGN(size, sizeof(struct memchunk));
 242         heap_use += size;
 243         if (heap_use > heap_max)
 244                 heap_max = heap_use;
 245         for (mpp = &freechunks; (mp = *mpp) != 0; mpp = &mp->next) {
 246                 if (mp->size == size) {
 247                         *mpp = mp->next;
 248                         return mp;
 249                 }
 250         }
 251         p = avail_ram;
 252         avail_ram += size;
 253         if (avail_ram > avail_high)
 254                 avail_high = avail_ram;
 255         if (avail_ram > end_avail) {
 256                 printf("oops... out of memory\n\r");
 257                 pause();
 258         }
 259         return p;
 260 }
 261
 262 void zfree(void *x, void *addr, unsigned nb)
 263 {
 264         struct memchunk *mp = addr;
 265
 266         nb = _ALIGN(nb, sizeof(struct memchunk));
 267         heap_use -= nb;
 268         if (avail_ram == addr + nb) {
 269                 avail_ram = addr;
 270                 return;
 271         }
 272         mp->size = nb;
 273         mp->next = freechunks;
 274         freechunks = mp;
 275 }
 276
 277 #define HEAD_CRC        2
 278 #define EXTRA_FIELD     4
 279 #define ORIG_NAME       8
 280 #define COMMENT         0x10
 281 #define RESERVED        0xe0
 282
 283 #define DEFLATED        8
 284
 285 void gunzip(void *dst, int dstlen, unsigned char *src, int *lenp)
 286 {
 287         z_stream s;
 288         int r, i, flags;
 289
 290         /* skip header */
 291         i = 10;
 292         flags = src[3];
 293         if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
 294                 printf("bad gzipped data\n\r");
 295                 exit();
 296         }
 297         if ((flags & EXTRA_FIELD) != 0)
 298                 i = 12 + src[10] + (src[11] << 8);
 299         if ((flags & ORIG_NAME) != 0)
 300                 while (src[i++] != 0)
 301                         ;
 302         if ((flags & COMMENT) != 0)
 303                 while (src[i++] != 0)
 304                         ;
 305         if ((flags & HEAD_CRC) != 0)
 306                 i += 2;
 307         if (i >= *lenp) {
 308                 printf("gunzip: ran out of data in header\n\r");
 309                 exit();
 310         }
 311
 312         s.zalloc = zalloc;
 313         s.zfree = zfree;
 314         r = inflateInit2(&s, -MAX_WBITS);
 315         if (r != Z_OK) {
 316                 printf("inflateInit2 returned %d\n\r", r);
 317                 exit();
 318         }
 319         s.next_in = src + i;
 320         s.avail_in = *lenp - i;
 321         s.next_out = dst;
 322         s.avail_out = dstlen;
 323         r = inflate(&s, Z_FINISH);
 324         if (r != Z_OK && r != Z_STREAM_END) {
 325                 printf("inflate returned %d msg: %s\n\r", r, s.msg);
 326                 exit();
 327         }
 328         *lenp = s.next_out - (unsigned char *) dst;
 329         inflateEnd(&s);
 330 }
 331