/*
* Copyright (C) 2013 Michael Brown <mbrown@fensystems.co.uk>.
*
* 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; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <errno.h>
#include <linux_api.h>
#include <ipxe/linux.h>
#include <ipxe/smbios.h>
/** SMBIOS filename */
static const char smbios_filename[] = "/dev/mem";
/** SMBIOS entry point scan region start address */
#define SMBIOS_ENTRY_START 0xf0000
/** SMBIOS entry point scan region length */
#define SMBIOS_ENTRY_LEN 0x10000
/** SMBIOS mapping alignment */
#define SMBIOS_ALIGN 0x1000
/**
* Find SMBIOS
*
* @v smbios SMBIOS entry point descriptor structure to fill in
* @ret rc Return status code
*/
static int linux_find_smbios ( struct smbios *smbios ) {
struct smbios_entry entry;
void *entry_mem;
void *smbios_mem;
size_t smbios_offset;
size_t smbios_indent;
size_t smbios_len;
int fd;
int rc;
/* Open SMBIOS file */
fd = linux_open ( smbios_filename, O_RDONLY );
if ( fd < 0 ) {
rc = -ELINUX ( linux_errno );
DBGC ( smbios, "SMBIOS could not open %s: %s\n",
smbios_filename, linux_strerror ( linux_errno ) );
goto err_open;
}
/* Map the region potentially containing the SMBIOS entry point */
entry_mem = linux_mmap ( NULL, SMBIOS_ENTRY_LEN, PROT_READ, MAP_SHARED,
fd, SMBIOS_ENTRY_START );
if ( entry_mem == MAP_FAILED ) {
rc = -ELINUX ( linux_errno );
DBGC ( smbios, "SMBIOS could not mmap %s (%#x+%#x): %s\n",
smbios_filename, SMBIOS_ENTRY_START, SMBIOS_ENTRY_LEN,
linux_strerror ( linux_errno ) );
goto err_mmap_entry;
}
/* Scan for the SMBIOS entry point */
if ( ( rc = find_smbios_entry ( virt_to_user ( entry_mem ),
SMBIOS_ENTRY_LEN, &entry ) ) != 0 )
goto err_find_entry;
/* Map the region containing the SMBIOS structures */
smbios_indent = ( entry.smbios_address & ( SMBIOS_ALIGN - 1 ) );
smbios_offset = ( entry.smbios_address - smbios_indent );
smbios_len = ( entry.smbios_len + smbios_indent );
smbios_mem = linux_mmap ( NULL, smbios_len, PROT_READ, MAP_SHARED,
fd, smbios_offset );
if ( smbios_mem == MAP_FAILED ) {
rc = -ELINUX ( linux_errno );
DBGC ( smbios, "SMBIOS could not mmap %s (%#zx+%#zx): %s\n",
smbios_filename, smbios_offset, smbios_len,
linux_strerror ( linux_errno ) );
goto err_mmap_smbios;
}
/* Fill in entry point descriptor structure */
smbios->address = virt_to_user ( smbios_mem + smbios_indent );
smbios->len = entry.smbios_len;
smbios->count = entry.smbios_count;
smbios->version = SMBIOS_VERSION ( entry.major, entry.minor );
/* Unmap the entry point region (no longer required) */
linux_munmap ( entry_mem, SMBIOS_ENTRY_LEN );
return 0;
linux_munmap ( smbios_mem, smbios_len );
err_mmap_smbios:
err_find_entry:
linux_munmap ( entry_mem, SMBIOS_ENTRY_LEN );
err_mmap_entry:
linux_close ( fd );
err_open:
return rc;
}
PROVIDE_SMBIOS ( linux, find_smbios, linux_find_smbios );
