/*
* Copyright (C) 2011 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 <stdio.h>
#include <string.h>
#include <errno.h>
#include <ipxe/efi/efi.h>
#include <ipxe/efi/efi_pci.h>
#include <ipxe/efi/efi_utils.h>
/** @file
*
* EFI utilities
*
*/
/**
* Find end of device path
*
* @v path Path to device
* @ret path_end End of device path
*/
EFI_DEVICE_PATH_PROTOCOL * efi_devpath_end ( EFI_DEVICE_PATH_PROTOCOL *path ) {
while ( path->Type != END_DEVICE_PATH_TYPE ) {
path = ( ( ( void * ) path ) +
/* There's this amazing new-fangled thing known as
* a UINT16, but who wants to use one of those? */
( ( path->Length[1] << 8 ) | path->Length[0] ) );
}
return path;
}
/**
* Find length of device path (excluding terminator)
*
* @v path Path to device
* @ret path_len Length of device path
*/
size_t efi_devpath_len ( EFI_DEVICE_PATH_PROTOCOL *path ) {
EFI_DEVICE_PATH_PROTOCOL *end = efi_devpath_end ( path );
return ( ( ( void * ) end ) - ( ( void * ) path ) );
}
/**
* Locate parent device supporting a given protocol
*
* @v device EFI device handle
* @v protocol Protocol GUID
* @v parent Parent EFI device handle to fill in
* @ret rc Return status code
*/
int efi_locate_device ( EFI_HANDLE device, EFI_GUID *protocol,
EFI_HANDLE *parent ) {
EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
union {
EFI_DEVICE_PATH_PROTOCOL *path;
void *interface;
} path;
EFI_DEVICE_PATH_PROTOCOL *devpath;
EFI_STATUS efirc;
int rc;
/* Get device path */
if ( ( efirc = bs->OpenProtocol ( device,
&efi_device_path_protocol_guid,
&path.interface,
efi_image_handle, device,
EFI_OPEN_PROTOCOL_GET_PROTOCOL ))!=0){
rc = -EEFI ( efirc );
DBGC ( device, "EFIDEV %s cannot open device path: %s\n",
efi_handle_name ( device ), strerror ( rc ) );
goto err_open_device_path;
}
devpath = path.path;
/* Check for presence of specified protocol */
if ( ( efirc = bs->LocateDevicePath ( protocol, &devpath,
parent ) ) != 0 ) {
rc = -EEFI ( efirc );
DBGC ( device, "EFIDEV %s has no parent supporting %s: %s\n",
efi_handle_name ( device ),
efi_guid_ntoa ( protocol ), strerror ( rc ) );
goto err_locate_protocol;
}
/* Success */
rc = 0;
err_locate_protocol:
bs->CloseProtocol ( device, &efi_device_path_protocol_guid,
efi_image_handle, device );
err_open_device_path:
return rc;
}
/**
* Add EFI device as child of another EFI device
*
* @v parent EFI parent device handle
* @v child EFI child device handle
* @ret rc Return status code
*/
int efi_child_add ( EFI_HANDLE parent, EFI_HANDLE child ) {
EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
void *devpath;
EFI_STATUS efirc;
int rc;
/* Re-open the device path protocol */
if ( ( efirc = bs->OpenProtocol ( parent,
&efi_device_path_protocol_guid,
&devpath,
efi_image_handle, child,
EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
) ) != 0 ) {
rc = -EEFI ( efirc );
DBGC ( parent, "EFIDEV %s could not add child",
efi_handle_name ( parent ) );
DBGC ( parent, " %s: %s\n",
efi_handle_name ( child ), strerror ( rc ) );
DBGC_EFI_OPENERS ( parent, parent,
&efi_device_path_protocol_guid );
return rc;
}
DBGC2 ( parent, "EFIDEV %s added child", efi_handle_name ( parent ) );
DBGC2 ( parent, " %s\n", efi_handle_name ( child ) );
return 0;
}
/**
* Remove EFI device as child of another EFI device
*
* @v parent EFI parent device handle
* @v child EFI child device handle
*/
void efi_child_del ( EFI_HANDLE parent, EFI_HANDLE child ) {
EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
bs->CloseProtocol ( parent, &efi_device_path_protocol_guid,
efi_image_handle, child );
DBGC2 ( parent, "EFIDEV %s removed child", efi_handle_name ( parent ) );
DBGC2 ( parent, " %s\n", efi_handle_name ( child ) );
}
/**
* Get underlying PCI device information
*
* @v device EFI device handle
* @v prefix Device name prefix
* @v dev Generic device to fill in
* @ret rc Return status code
*/
static int efi_pci_info ( EFI_HANDLE device, const char *prefix,
struct device *dev ) {
EFI_HANDLE pci_device;
struct pci_device pci;
int rc;
/* Find parent PCI device */
if ( ( rc = efi_locate_device ( device, &efi_pci_io_protocol_guid,
&pci_device ) ) != 0 ) {
DBGC ( device, "EFIDEV %s is not a PCI device: %s\n",
efi_handle_name ( device ), strerror ( rc ) );
return rc;
}
/* Get PCI device information */
if ( ( rc = efipci_info ( pci_device, &pci ) ) != 0 ) {
DBGC ( device, "EFIDEV %s could not get PCI information: %s\n",
efi_handle_name ( device ), strerror ( rc ) );
return rc;
}
/* Populate device information */
memcpy ( &dev->desc, &pci.dev.desc, sizeof ( dev->desc ) );
snprintf ( dev->name, sizeof ( dev->name ), "%s-%s",
prefix, pci.dev.name );
return 0;
}
/**
* Get underlying device information
*
* @v device EFI device handle
* @v prefix Device name prefix
* @v dev Generic device to fill in
*/
void efi_device_info ( EFI_HANDLE device, const char *prefix,
struct device *dev ) {
int rc;
/* Try getting underlying PCI device information */
if ( ( rc = efi_pci_info ( device, prefix, dev ) ) == 0 )
return;
/* If we cannot get any underlying device information, fall
* back to providing information about the EFI handle.
*/
DBGC ( device, "EFIDEV %s could not get underlying device "
"information\n", efi_handle_name ( device ) );
dev->desc.bus_type = BUS_TYPE_EFI;
snprintf ( dev->name, sizeof ( dev->name ), "%s-%p", prefix, device );
}
