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freebsd-dev/sys/boot/i386/libi386/biossmap.c

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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
/*-
* 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.
*/
Use __FBSDID(). Also some minor copyright style cleanups.
2003-08-25 23:28:32 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
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
/*
* 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;
Long-long time ago, when the trees were large and memory expensive amount of memory directly available to loader(8) and friends was limited to 640K on i386. Those times have passed long time ago and now loader(8) can directly access up to 4GB of RAM at least theoretically. At the same time, there are several places where it's assumed that malloc() will only allocate memory within first megabyte. Remove that assumption by allocating appropriate bounce buffers for BIOS calls on stack where necessary. This allows using memory above first megabyte for heap if necessary.
2005-12-19 09:00:11 +00:00
v86.es = VTOPSEG(&smap);
v86.edi = VTOPOFF(&smap);
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
v86int();
Long-long time ago, when the trees were large and memory expensive amount of memory directly available to loader(8) and friends was limited to 640K on i386. Those times have passed long time ago and now loader(8) can directly access up to 4GB of RAM at least theoretically. At the same time, there are several places where it's assumed that malloc() will only allocate memory within first megabyte. Remove that assumption by allocating appropriate bounce buffers for BIOS calls on stack where necessary. This allows using memory above first megabyte for heap if necessary.
2005-12-19 09:00:11 +00:00
bcopy(&smap, &smapbase[smaplen], sizeof(struct smap));
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
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);
}
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