freebsd-dev/sys/boot/i386/libi386/biossmap.c
Peter Wemm 48a0b96a50 Enable the i386 loader to load and run an amd64 kernel. If this puts
things over floppy size limits, I can exclude it for release builds or
something like that.  Most of the changes are to get the load_elf.c file
into a seperate elf32_ or elf64_ namespace so that you can have two
ELF loaders present at once.  Note that for 64 bit kernels, it actually
starts up the kernel already in 64 bit mode with paging enabled.  This
is really easy because we have a known minimum feature set.

Of note is that for amd64, we have to pass in the bios int 15 0xe821
memory map because once in long mode, you absolutely cannot make VM86
calls.  amd64 does not use 'struct bootinfo' at all.  It is a pure loader
metadata startup, just like sparc64 and powerpc.  Much of the
infrastructure to support this was adapted from sparc64.
2003-05-01 03:56:30 +00:00

108 lines
3.0 KiB
C

/*-
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* Obtain memory configuration information from the BIOS
*/
#include <stand.h>
#include <sys/param.h>
#include <sys/linker.h>
#include <machine/metadata.h>
#include "bootstrap.h"
#include "libi386.h"
#include "btxv86.h"
#define SMAPSIG 0x534D4150
struct smap {
u_int64_t base;
u_int64_t length;
u_int32_t type;
} __packed;
static struct smap smap;
static struct smap *smapbase;
static int smaplen;
void
bios_getsmap(void)
{
int n;
n = 0;
smaplen = 0;
/* Count up segments in system memory map */
v86.ebx = 0;
do {
v86.ctl = V86_FLAGS;
v86.addr = 0x15; /* int 0x15 function 0xe820*/
v86.eax = 0xe820;
v86.ecx = sizeof(struct smap);
v86.edx = SMAPSIG;
v86.es = VTOPSEG(&smap);
v86.edi = VTOPOFF(&smap);
v86int();
if ((v86.efl & 1) || (v86.eax != SMAPSIG))
break;
n++;
} while (v86.ebx != 0);
if (n == 0)
return;
n += 10; /* spare room */
smapbase = malloc(n * sizeof(*smapbase));
/* Save system memory map */
v86.ebx = 0;
do {
v86.ctl = V86_FLAGS;
v86.addr = 0x15; /* int 0x15 function 0xe820*/
v86.eax = 0xe820;
v86.ecx = sizeof(struct smap);
v86.edx = SMAPSIG;
v86.es = VTOPSEG(&smapbase[smaplen]);
v86.edi = VTOPOFF(&smapbase[smaplen]);
v86int();
smaplen++;
if ((v86.efl & 1) || (v86.eax != SMAPSIG))
break;
} while (v86.ebx != 0 && smaplen < n);
}
void
bios_addsmapdata(struct preloaded_file *kfp)
{
int len;
if (smapbase == 0 || smaplen == 0)
return;
len = smaplen * sizeof(*smapbase);
file_addmetadata(kfp, MODINFOMD_SMAP, len, smapbase);
/* Temporary compatability with older development kernels */
file_addmetadata(kfp, 0x0009, len, smapbase);
}