forked from Minki/linux
193c3cc125
Move the xtime write mode seqlock into timer_tick(), so it only surrounds the call to do_timer(). This avoids a deadlock in update_process_times() ... hrtimer_get_softirq_time() which tries to get a read mode seqlock on xtime, thereby preventing booting. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
103 lines
2.7 KiB
C
103 lines
2.7 KiB
C
/*
|
|
* arch/arm/mach-netx/time.c
|
|
*
|
|
* Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* 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/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/clocksource.h>
|
|
|
|
#include <asm/hardware.h>
|
|
#include <asm/io.h>
|
|
#include <asm/mach/time.h>
|
|
#include <asm/arch/netx-regs.h>
|
|
|
|
/*
|
|
* IRQ handler for the timer
|
|
*/
|
|
static irqreturn_t
|
|
netx_timer_interrupt(int irq, void *dev_id)
|
|
{
|
|
timer_tick();
|
|
|
|
/* acknowledge interrupt */
|
|
writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static struct irqaction netx_timer_irq = {
|
|
.name = "NetX Timer Tick",
|
|
.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
|
|
.handler = netx_timer_interrupt,
|
|
};
|
|
|
|
cycle_t netx_get_cycles(void)
|
|
{
|
|
return readl(NETX_GPIO_COUNTER_CURRENT(1));
|
|
}
|
|
|
|
static struct clocksource clocksource_netx = {
|
|
.name = "netx_timer",
|
|
.rating = 200,
|
|
.read = netx_get_cycles,
|
|
.mask = CLOCKSOURCE_MASK(32),
|
|
.shift = 20,
|
|
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
|
|
};
|
|
|
|
/*
|
|
* Set up timer interrupt
|
|
*/
|
|
static void __init netx_timer_init(void)
|
|
{
|
|
/* disable timer initially */
|
|
writel(0, NETX_GPIO_COUNTER_CTRL(0));
|
|
|
|
/* Reset the timer value to zero */
|
|
writel(0, NETX_GPIO_COUNTER_CURRENT(0));
|
|
|
|
writel(LATCH, NETX_GPIO_COUNTER_MAX(0));
|
|
|
|
/* acknowledge interrupt */
|
|
writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
|
|
|
|
/* Enable the interrupt in the specific timer register and start timer */
|
|
writel(COUNTER_BIT(0), NETX_GPIO_IRQ_ENABLE);
|
|
writel(NETX_GPIO_COUNTER_CTRL_IRQ_EN | NETX_GPIO_COUNTER_CTRL_RUN,
|
|
NETX_GPIO_COUNTER_CTRL(0));
|
|
|
|
setup_irq(NETX_IRQ_TIMER0, &netx_timer_irq);
|
|
|
|
/* Setup timer one for clocksource */
|
|
writel(0, NETX_GPIO_COUNTER_CTRL(1));
|
|
writel(0, NETX_GPIO_COUNTER_CURRENT(1));
|
|
writel(0xFFFFFFFF, NETX_GPIO_COUNTER_MAX(1));
|
|
|
|
writel(NETX_GPIO_COUNTER_CTRL_RUN,
|
|
NETX_GPIO_COUNTER_CTRL(1));
|
|
|
|
clocksource_netx.mult =
|
|
clocksource_hz2mult(CLOCK_TICK_RATE, clocksource_netx.shift);
|
|
clocksource_register(&clocksource_netx);
|
|
}
|
|
|
|
struct sys_timer netx_timer = {
|
|
.init = netx_timer_init,
|
|
};
|