/*
* Copyright (C) 2008 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.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <ipxe/timer.h>
#include <ipxe/init.h>
#include <ipxe/efi/efi.h>
/** @file
*
* iPXE timer API for EFI
*
*/
/** Current tick count */
static unsigned long efi_jiffies;
/** Timer tick event */
static EFI_EVENT efi_tick_event;
/** Colour for debug messages */
#define colour &efi_jiffies
/**
* Delay for a fixed number of microseconds
*
* @v usecs Number of microseconds for which to delay
*/
static void efi_udelay ( unsigned long usecs ) {
EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
EFI_STATUS efirc;
int rc;
if ( ( efirc = bs->Stall ( usecs ) ) != 0 ) {
rc = -EEFI ( efirc );
DBGC ( colour, "EFI could not delay for %ldus: %s\n",
usecs, strerror ( rc ) );
/* Probably screwed */
}
}
/**
* Get current system time in ticks
*
* @ret ticks Current time, in ticks
*/
static unsigned long efi_currticks ( void ) {
return efi_jiffies;
}
/**
* Timer tick
*
* @v event Timer tick event
* @v context Event context
*/
static EFIAPI void efi_tick ( EFI_EVENT event __unused,
void *context __unused ) {
/* Increment tick count */
efi_jiffies++;
}
/**
* Start timer tick
*
*/
static void efi_tick_startup ( void ) {
EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
EFI_STATUS efirc;
int rc;
/* Create timer tick event */
if ( ( efirc = bs->CreateEvent ( ( EVT_TIMER | EVT_NOTIFY_SIGNAL ),
TPL_CALLBACK, efi_tick, NULL,
&efi_tick_event ) ) != 0 ) {
rc = -EEFI ( efirc );
DBGC ( colour, "EFI could not create timer tick: %s\n",
strerror ( rc ) );
/* Nothing we can do about it */
return;
}
/* Start timer tick */
if ( ( efirc = bs->SetTimer ( efi_tick_event, TimerPeriodic,
( 10000000 / EFI_TICKS_PER_SEC ) ) ) !=0){
rc = -EEFI ( efirc );
DBGC ( colour, "EFI could not start timer tick: %s\n",
strerror ( rc ) );
/* Nothing we can do about it */
return;
}
DBGC ( colour, "EFI timer started at %d ticks per second\n",
EFI_TICKS_PER_SEC );
}
/**
* Stop timer tick
*
* @v booting System is shutting down in order to boot
*/
static void efi_tick_shutdown ( int booting __unused ) {
EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
/* Stop timer tick */
bs->SetTimer ( efi_tick_event, TimerCancel, 0 );
DBGC ( colour, "EFI timer stopped\n" );
/* Destroy timer tick event */
bs->CloseEvent ( efi_tick_event );
}
/** Timer tick startup function */
struct startup_fn efi_tick_startup_fn __startup_fn ( STARTUP_EARLY ) = {
.startup = efi_tick_startup,
.shutdown = efi_tick_shutdown,
};
PROVIDE_TIMER ( efi, udelay, efi_udelay );
PROVIDE_TIMER ( efi, currticks, efi_currticks );
PROVIDE_TIMER_INLINE ( efi, ticks_per_sec );
