71 lines
2.1 KiB
C
71 lines
2.1 KiB
C
/*
|
|
* Copyright (C) 2000, 2001 Broadcom Corporation
|
|
*
|
|
* 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 (at your option) 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
*/
|
|
#include <linux/clocksource.h>
|
|
|
|
#include <asm/addrspace.h>
|
|
#include <asm/io.h>
|
|
#include <asm/time.h>
|
|
|
|
#include <asm/sibyte/sb1250.h>
|
|
#include <asm/sibyte/sb1250_regs.h>
|
|
#include <asm/sibyte/sb1250_int.h>
|
|
#include <asm/sibyte/sb1250_scd.h>
|
|
|
|
#define SB1250_HPT_NUM 3
|
|
#define SB1250_HPT_VALUE M_SCD_TIMER_CNT /* max value */
|
|
|
|
/*
|
|
* The HPT is free running from SB1250_HPT_VALUE down to 0 then starts over
|
|
* again.
|
|
*/
|
|
static cycle_t sb1250_hpt_read(void)
|
|
{
|
|
unsigned int count;
|
|
|
|
count = G_SCD_TIMER_CNT(__raw_readq(IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM, R_SCD_TIMER_CNT))));
|
|
|
|
return SB1250_HPT_VALUE - count;
|
|
}
|
|
|
|
struct clocksource bcm1250_clocksource = {
|
|
.name = "bcm1250-counter-3",
|
|
.rating = 200,
|
|
.read = sb1250_hpt_read,
|
|
.mask = CLOCKSOURCE_MASK(23),
|
|
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
|
|
};
|
|
|
|
void __init sb1250_clocksource_init(void)
|
|
{
|
|
struct clocksource *cs = &bcm1250_clocksource;
|
|
|
|
/* Setup hpt using timer #3 but do not enable irq for it */
|
|
__raw_writeq(0,
|
|
IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
|
|
R_SCD_TIMER_CFG)));
|
|
__raw_writeq(SB1250_HPT_VALUE,
|
|
IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
|
|
R_SCD_TIMER_INIT)));
|
|
__raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
|
|
IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
|
|
R_SCD_TIMER_CFG)));
|
|
|
|
clocksource_set_clock(cs, V_SCD_TIMER_FREQ);
|
|
clocksource_register(cs);
|
|
}
|