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/* ----------------------------------------------------------------------- *
*
* Copyright 2001-2008 H. Peter Anvin - All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, Inc., 53 Temple Place Ste 330,
* Boston MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* msetup.c
*
* Initialization code for memory-based disk
*/
#include <stdint.h>
#include "memdisk.h"
#include "conio.h"
#include "e820.h"
static inline int get_e820(void)
{
struct e820_info {
uint64_t base;
uint64_t len;
uint32_t type;
uint32_t extattr;
} *buf = sys_bounce;
uint32_t copied;
int range_count = 0;
com32sys_t regs;
memset(®s, 0, sizeof regs);
do {
regs.eax.l = 0x0000e820;
regs.ecx.l = sizeof(*buf);
regs.edx.l = 0x534d4150;
regs.edi.w[0] = OFFS(buf);
regs.es = SEG(buf);
syscall(0x15, ®s, ®s);
copied = (regs.eflags.l & 1) ? 0 : regs.ecx.l;
if ( regs.eax.l != 0x534d4150 || copied < 20 )
break;
if ( copied < 24 )
buf->extattr = 1;
printf("e820: %08x%08x %08x%08x %d [%x]\n",
(uint32_t)(buf->base >> 32), (uint32_t)buf->base,
(uint32_t)(buf->len >> 32), (uint32_t)buf->len,
buf->type, buf->extattr);
if ( !(buf->extattr & 1) )
continue; /* Disabled range, just ignore */
insertrange(buf->base, buf->len, buf->type, buf->extattr);
range_count++;
} while ( regs.ebx.l );
return !range_count;
}
static inline void get_dos_mem(void)
{
com32sys_t regs;
memset(®s, 0, sizeof regs);
syscall(0x12, ®s, ®s);
insertrange(0, (uint64_t)((uint32_t)regs.eax.w[0] << 10), 1, 1);
printf(" DOS: %d K\n", regs.eax.w[0]);
}
static inline int get_e801(void)
{
int err;
com32sys_t regs;
memset(®s, 0, sizeof regs);
regs.eax.w[0] = 0xe801;
syscall(0x15, ®s, ®s);
if ( !(err = regs.eflags.l & 1) ) {
if ( regs.eax.w[0] ) {
insertrange(0x100000, (uint64_t)((uint32_t)regs.eax.w[0] << 10), 1, 1);
}
if ( regs.ebx.w[0] ) {
insertrange(0x1000000, (uint64_t)((uint32_t)regs.ebx.w[0] << 16), 1, 1);
}
printf("e801: %04x %04x\n", regs.eax.w[0], regs.ebx.w[0]);
}
return err;
}
static inline int get_88(void)
{
com32sys_t regs;
int err;
memset(®s, 0, sizeof regs);
regs.eax.b[1] = 0x88;
syscall(0x15, ®s, ®s);
if ( !(err = regs.eflags.l & 1) ) {
if ( regs.eax.w[0] ) {
insertrange(0x100000, (uint64_t)((uint32_t)regs.eax.w[0] << 10), 1, 1);
}
printf(" 88: %04x\n", regs.eax.w[0]);
}
return err;
}
uint32_t dos_mem = 0; /* 0-1MB */
uint32_t low_mem = 0; /* 1-16MB */
uint32_t high_mem = 0; /* 16+ MB */
void get_mem(void)
{
if ( get_e820() ) {
get_dos_mem();
if ( get_e801() ) {
if ( get_88() ) {
puts("MEMDISK: Unable to obtain memory map\n");
die();
}
}
}
}
#define PW(x) (1ULL << (x))
void parse_mem(void)
{
struct e820range *ep;
dos_mem = low_mem = high_mem = 0;
/* Derive "dos mem", "high mem", and "low mem" from the range array */
for ( ep = ranges ; ep->type != -1 ; ep++ ) {
if ( ep->type == 1 ) {
/* Only look at memory ranges */
if ( ep->start == 0 ) {
if ( ep[1].start > PW(20) )
dos_mem = PW(20);
else
dos_mem = ep[1].start;
}
if ( ep->start <= PW(20) && ep[1].start > PW(20) ) {
if ( ep[1].start > PW(24) )
low_mem = PW(24) - PW(20);
else
low_mem = ep[1].start - PW(20);
}
if ( ep->start <= PW(24) && ep[1].start > PW(24) ) {
if ( ep[1].start > PW(32) )
high_mem = PW(32) - PW(24);
else
high_mem = ep[1].start - PW(24);
}
}
}
}
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