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 <stdbool.h>
  17 #include "mystuff.h"
  18 #include "ymsend.h"
  19 #include "srecsend.h"
  20 #include "io.h"
  21
  22 const char *program = "memdump";
  23
  24 void __attribute__ ((noreturn)) die(const char *msg)
  25 {
  26     puts(program);
  27     puts(": ");
  28     puts(msg);
  29     putchar('\n');
  30     exit(1);
  31 }
  32
  33 #ifdef DEBUG
  34 # define dprintf printf
  35 #else
  36 # define dprintf(...) ((void)0)
  37 #endif
  38
  39 static inline __attribute__ ((const))
  40 uint16_t ds(void)
  41 {
  42     uint16_t v;
  43 asm("movw %%ds,%0":"=rm"(v));
  44     return v;
  45 }
  46
  47 #define GDT_ENTRY(flags,base,limit)             \
  48         (((uint64_t)(base & 0xff000000) << 32) |        \
  49          ((uint64_t)flags << 40) |                      \
  50          ((uint64_t)(limit & 0x00ff0000) << 32) |       \
  51          ((uint64_t)(base & 0x00ffff00) << 16) |        \
  52          ((uint64_t)(limit & 0x0000ffff)))
  53
  54 static void get_bytes(void *buf, size_t len, struct file_info *finfo,
  55                       size_t pos)
  56 {
  57     size_t end;
  58     static uint64_t gdt[6];
  59     size_t bufl;
  60
  61     pos += (size_t) finfo->pvt; /* Add base */
  62     end = pos + len;
  63
  64     if (end <= 0x100000) {
  65         /* Can stay in real mode */
  66         asm volatile ("movw %3,%%fs ; "
  67                       "fs; rep; movsl ; "
  68                       "movw %2,%%cx ; "
  69                       "rep; movsb"::"D" (buf), "c"(len >> 2),
  70                       "r"((uint16_t) (len & 3)), "rm"((uint16_t) (pos >> 4)),
  71                       "S"(pos & 15)
  72                       :"memory");
  73     } else {
  74         bufl = (ds() << 4) + (size_t) buf;
  75         gdt[2] = GDT_ENTRY(0x0093, pos, 0xffff);
  76         gdt[3] = GDT_ENTRY(0x0093, bufl, 0xffff);
  77         asm volatile ("pushal ; int $0x15 ; popal"::"a" (0x8700),
  78                       "c"((len + 1) >> 1), "S"(&gdt)
  79                       :"memory");
  80     }
  81 }
  82
  83 int main(int argc, char *argv[])
  84 {
  85     uint16_t bios_ports[4];
  86     const char *prefix;
  87     char filename[1024];
  88     int i;
  89     static struct serial_if sif = {
  90         .read = serial_read,
  91         .write = serial_write,
  92     };
  93     struct file_info finfo;
  94     const char ymodem_banner[] = "Now begin Ymodem download...\r\n";
  95     bool srec = false;
  96
  97     if (argv[1][0] == '-') {
  98         srec = argv[1][1] == 's';
  99         argc--;
 100         argv++;
 101     }
 102
 103     if (argc < 4)
 104         die("usage: memdump [-s] port prefix start,len...");
 105
 106     finfo.pvt = (void *)0x400;
 107     get_bytes(bios_ports, 8, &finfo, 0);        /* Get BIOS serial ports */
 108
 109     for (i = 0; i < 4; i++)
 110         printf("ttyS%i (COM%i) is at %#x\n", i, i + 1, bios_ports[i]);
 111
 112     sif.port = strtoul(argv[1], NULL, 0);
 113     if (sif.port <= 3) {
 114         sif.port = bios_ports[sif.port];
 115     }
 116
 117     if (serial_init(&sif))
 118         die("failed to initialize serial port");
 119
 120     prefix = argv[2];
 121
 122     if (!srec) {
 123         puts("Printing prefix...\n");
 124         sif.write(&sif, ymodem_banner, sizeof ymodem_banner - 1);
 125     }
 126
 127     for (i = 3; i < argc; i++) {
 128         uint32_t start, len;
 129         char *ep;
 130
 131         start = strtoul(argv[i], &ep, 0);
 132         if (*ep != ',')
 133             die("invalid range specification");
 134         len = strtoul(ep + 1, NULL, 0);
 135
 136         sprintf(filename, "%s%#x-%#x.bin", prefix, start, len);
 137         finfo.name = filename;
 138         finfo.size = len;
 139         finfo.pvt = (void *)start;
 140
 141         puts("Sending ");
 142         puts(filename);
 143         puts("...\n");
 144
 145         if (srec)
 146             send_srec(&sif, &finfo, get_bytes);
 147         else
 148             send_ymodem(&sif, &finfo, get_bytes);
 149     }
 150
 151     if (!srec) {
 152         puts("Sending closing signature...\n");
 153         end_ymodem(&sif);
 154     }
 155
 156     return 0;
 157 }