arch/ppc/boot/openfirmware/newworldmain.c

   1 /*
   2  * Copyright (C) Paul Mackerras 1997.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  */
   9 #include <linux/string.h>
  10 #include "nonstdio.h"
  11 #include "of1275.h"
  12 #include <asm/processor.h>
  13 #include <asm/page.h>
  14
  15 /* Passed from the linker */
  16 extern char __image_begin, __image_end;
  17 extern char __ramdisk_begin[], __ramdisk_end;
  18 extern char _start, _end;
  19
  20 extern unsigned int heap_max;
  21 extern void flush_cache(void *start, unsigned int len);
  22 extern void gunzip(void *, int, unsigned char *, int *);
  23 extern void make_bi_recs(unsigned long addr, char *name, unsigned int mach,
  24                 unsigned int progend);
  25
  26 char *avail_ram;
  27 char *begin_avail, *end_avail;
  28 char *avail_high;
  29
  30
  31 #define RAM_END         (16 << 20)
  32
  33 #define PROG_START      0x00010000
  34 #define PROG_SIZE       0x007f0000
  35
  36 #define SCRATCH_SIZE    (128 << 10)
  37
  38 typedef void (*kernel_start_t)(int, int, void *);
  39
  40 void boot(int a1, int a2, void *prom)
  41 {
  42     unsigned sa, len;
  43     void *dst;
  44     unsigned char *im;
  45     unsigned initrd_start, initrd_size;
  46
  47     printf("chrpboot starting: loaded at 0x%p\n", &_start);
  48
  49     initrd_size = (char *)(&__ramdisk_end) - (char *)(&__ramdisk_begin);
  50     if (initrd_size) {
  51         initrd_start = (RAM_END - initrd_size) & ~0xFFF;
  52         a1 = initrd_start;
  53         a2 = initrd_size;
  54         claim(initrd_start, RAM_END - initrd_start, 0);
  55         printf("initial ramdisk moving 0x%x <- 0x%p (%x bytes)\n\r",
  56                initrd_start, (char *)(&__ramdisk_begin), initrd_size);
  57         memcpy((char *)initrd_start, (char *)(&__ramdisk_begin), initrd_size);
  58     } else
  59         a2 = 0xdeadbeef;
  60
  61     im = (char *)(&__image_begin);
  62     len = (char *)(&__image_end) - (char *)(&__image_begin);
  63     /* claim 3MB starting at PROG_START */
  64     claim(PROG_START, PROG_SIZE, 0);
  65     dst = (void *) PROG_START;
  66     if (im[0] == 0x1f && im[1] == 0x8b) {
  67         /* claim some memory for scratch space */
  68         avail_ram = (char *) claim(0, SCRATCH_SIZE, 0x10);
  69         begin_avail = avail_high = avail_ram;
  70         end_avail = avail_ram + SCRATCH_SIZE;
  71         printf("heap at 0x%p\n", avail_ram);
  72         printf("gunzipping (0x%p <- 0x%p:0x%p)...", dst, im, im+len);
  73         gunzip(dst, PROG_SIZE, im, &len);
  74         printf("done %u bytes\n", len);
  75         printf("%u bytes of heap consumed, max in use %u\n",
  76                avail_high - begin_avail, heap_max);
  77         release(begin_avail, SCRATCH_SIZE);
  78     } else {
  79         memmove(dst, im, len);
  80     }
  81
  82     flush_cache(dst, len);
  83     make_bi_recs(((unsigned long) dst + len), "chrpboot", _MACH_Pmac,
  84                     (PROG_START + PROG_SIZE));
  85
  86     sa = (unsigned long)PROG_START;
  87     printf("start address = 0x%x\n", sa);
  88
  89     (*(kernel_start_t)sa)(a1, a2, prom);
  90
  91     printf("returned?\n");
  92
  93     pause();
  94 }