memdump/main.c

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2007-2008 H. Peter Anvin - All Rights Reserved
   4  *
   5  *   This program is free software; you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
   8  *   Boston MA 02111-1307, USA; either version 2 of the License, or
   9  *   (at your option) any later version; incorporated herein by reference.
  10  *
  11  * ----------------------------------------------------------------------- */
  12
  13 #include <stdio.h>
  14 #include <string.h>
  15 #include <stdlib.h>
  16 #include "mystuff.h"
  17 #include "ymsend.h"
  18 #include "io.h"
  19
  20 const char *program = "memdump";
  21
  22 void __attribute__((noreturn)) die(const char *msg)
  23 {
  24   puts(program);
  25   puts(": ");
  26   puts(msg);
  27   putchar('\n');
  28   exit(1);
  29 }
  30
  31 #ifdef DEBUG
  32 # define dprintf printf
  33 #else
  34 # define dprintf(...) ((void)0)
  35 #endif
  36
  37 static inline __attribute__((const)) uint16_t ds(void)
  38 {
  39   uint16_t v;
  40   asm("movw %%ds,%0" : "=rm" (v));
  41   return v;
  42 }
  43
  44 #define GDT_ENTRY(flags,base,limit)             \
  45         (((uint64_t)(base & 0xff000000) << 32) |        \
  46          ((uint64_t)flags << 40) |                      \
  47          ((uint64_t)(limit & 0x00ff0000) << 32) |       \
  48          ((uint64_t)(base & 0x00ffff00) << 16) |        \
  49          ((uint64_t)(limit & 0x0000ffff)))
  50
  51 static void get_bytes(void *buf, size_t len, struct file_info *finfo,
  52                       size_t pos)
  53 {
  54   size_t end;
  55   static uint64_t gdt[6];
  56   size_t bufl;
  57
  58   pos += (size_t)finfo->pvt;    /* Add base */
  59   end = pos+len;
  60
  61   if (end <= 0x100000) {
  62     /* Can stay in real mode */
  63     asm volatile("movw %3,%%fs ; "
  64                  "fs; rep; movsl ; "
  65                  "movw %2,%%cx ; "
  66                  "rep; movsb"
  67                  : : "D" (buf), "c" (len >> 2), "r" ((uint16_t)(len & 3)),
  68                  "rm" ((uint16_t)(pos >> 4)), "S" (pos & 15)
  69                  : "memory");
  70   } else {
  71     bufl = (ds() << 4)+(size_t)buf;
  72     gdt[2] = GDT_ENTRY(0x0093, pos, 0xffff);
  73     gdt[3] = GDT_ENTRY(0x0093, bufl, 0xffff);
  74     asm volatile("pushal ; int $0x15 ; popal"
  75                  : : "a" (0x8700), "c" ((len+1) >> 1), "S" (&gdt)
  76                  : "memory");
  77   }
  78 }
  79
  80 int main(int argc, char *argv[])
  81 {
  82   uint16_t bios_ports[4];
  83   const char *prefix;
  84   char filename[1024];
  85   int i;
  86   static struct serial_if sif =
  87     {
  88       .read  = serial_read,
  89       .write = serial_write,
  90     };
  91   struct file_info finfo;
  92   const char serial_banner[] = "Now begin Ymodem download...\r\n";
  93
  94   if (argc < 4)
  95     die("usage: memdump port prefix start,len...");
  96
  97   finfo.pvt = (void *)0x400;
  98   get_bytes(bios_ports, 8, &finfo, 0); /* Get BIOS serial ports */
  99
 100   for (i = 0; i < 4; i++)
 101     printf("ttyS%i (COM%i) is at %#x\n", i, i+1, bios_ports[i]);
 102
 103   sif.port = strtoul(argv[1], NULL, 0);
 104   if (sif.port <= 3) {
 105     sif.port = bios_ports[sif.port];
 106   }
 107
 108   if (serial_init(&sif))
 109     die("failed to initialize serial port");
 110
 111   prefix = argv[2];
 112
 113   puts("Printing prefix...\n");
 114   sif.write(&sif, serial_banner, sizeof serial_banner-1);
 115
 116   for (i = 3; i < argc; i++) {
 117     uint32_t start, len;
 118     char *ep;
 119
 120     start = strtoul(argv[i], &ep, 0);
 121     if (*ep != ',')
 122       die("invalid range specification");
 123     len = strtoul(ep+1, NULL, 0);
 124
 125     sprintf(filename, "%s%#x-%#x.bin", prefix, start, len);
 126     finfo.name = filename;
 127     finfo.size = len;
 128     finfo.pvt  = (void *)start;
 129
 130     puts("Sending ");
 131     puts(filename);
 132     puts("...\n");
 133
 134     send_ymodem(&sif, &finfo, get_bytes);
 135   }
 136
 137   puts("Sending closing signature...\n");
 138   end_ymodem(&sif);
 139
 140   return 0;
 141 }