boot/x86_64/stage1.c

   1 /*
   2 ** Copyright 2001-2004, Travis Geiselbrecht. All rights reserved.
   3 ** Distributed under the terms of the NewOS License.
   4 */
   5 #include <string.h>
   6 #include <stdarg.h>
   7 #include <stdio.h>
   8 #include <boot/stage2.h>
   9 #include <boot/bootdir.h>
  10 #include "stage1.h"
  11 #include "inflate.h"
  12
  13 // needed for console stuff
  14 static unsigned short *kScreenBase = (unsigned short*) 0xb8000;
  15 static unsigned screenOffset = 0;
  16 static unsigned int line = 0;
  17
  18 #define SCREEN_WIDTH 80
  19 #define SCREEN_HEIGHT 25
  20 #define PAGE_SIZE 4096
  21
  22 static unsigned char *heap_ptr = (unsigned char *)0x1000000;
  23
  24 extern void *_end;
  25 #define TARGET ((void *)0x400000)
  26
  27 void _start(unsigned int mem, void *ext_mem_block, int ext_mem_count, int in_vesa, unsigned int vesa_ptr)
  28 {
  29         unsigned long len;
  30         boot_dir *bootdir = TARGET;
  31         void (*stage2_entry)(unsigned int mem, void *ext_mem_block, int ext_mem_count, int in_vesa, unsigned int vesa_ptr, int console_ptr);
  32
  33         clearscreen();
  34
  35         dprintf("stage1 boot, decompressing system");
  36
  37         len = gunzip((unsigned char const *)&_end, TARGET, kmalloc(32*1024));
  38         dprintf("done, len %d\n", len);
  39
  40         dprintf("finding stage2...");
  41         stage2_entry = (void*)((char *)bootdir + bootdir->bd_entry[1].be_offset * PAGE_SIZE + bootdir->bd_entry[1].be_code_ventr);
  42         dprintf("entry at %p\n", stage2_entry);
  43
  44         // jump into stage2
  45         stage2_entry(mem, ext_mem_block, ext_mem_count, in_vesa, vesa_ptr, screenOffset);
  46 }
  47
  48 void *kmalloc(unsigned int size)
  49 {
  50 //      dprintf("kmalloc: size %d, ptr %p\n", size, heap_ptr - size);
  51
  52         return (heap_ptr -= size);
  53 }
  54
  55 void kfree(void *ptr)
  56 {
  57 }
  58
  59 void clearscreen()
  60 {
  61         int i;
  62
  63         for(i=0; i< SCREEN_WIDTH*SCREEN_HEIGHT*2; i++) {
  64                 kScreenBase[i] = 0xf20;
  65         }
  66 }
  67
  68 static void scrup()
  69 {
  70         int i;
  71         memcpy(kScreenBase, kScreenBase + SCREEN_WIDTH,
  72                 SCREEN_WIDTH * SCREEN_HEIGHT * 2 - SCREEN_WIDTH * 2);
  73         screenOffset = (SCREEN_HEIGHT - 1) * SCREEN_WIDTH;
  74         for(i=0; i<SCREEN_WIDTH; i++)
  75                 kScreenBase[screenOffset + i] = 0x0720;
  76         line = SCREEN_HEIGHT - 1;
  77 }
  78
  79 void puts(const char *str)
  80 {
  81         while (*str) {
  82                 if (*str == '\n') {
  83                         line++;
  84                         if(line > SCREEN_HEIGHT - 1)
  85                                 scrup();
  86                         else
  87                                 screenOffset += SCREEN_WIDTH - (screenOffset % 80);
  88                 } else {
  89                         kScreenBase[screenOffset++] = 0xf00 | *str;
  90                 }
  91                 if (screenOffset >= SCREEN_WIDTH * SCREEN_HEIGHT)
  92                         scrup();
  93
  94                 str++;
  95         }
  96 }
  97
  98 int dprintf(const char *fmt, ...)
  99 {
 100         int ret;
 101         va_list args;
 102         char temp[256];
 103
 104         va_start(args, fmt);
 105         ret = vsprintf(temp,fmt,args);
 106         va_end(args);
 107
 108         puts(temp);
 109         return ret;
 110 }
 111
 112
 113 int panic(const char *fmt, ...)
 114 {
 115         int ret;
 116         va_list args;
 117         char temp[256];
 118
 119         va_start(args, fmt);
 120         ret = vsprintf(temp,fmt,args);
 121         va_end(args);
 122
 123         puts("STAGE1 PANIC: ");
 124         puts(temp);
 125         puts("\n");
 126
 127         puts("spinning forever...");
 128         for(;;);
 129         return ret;
 130 }
 131