mirror of
https://github.com/torvalds/linux.git
synced 2024-12-26 04:42:12 +00:00
c22437b78e
Migrate netx driver to the new 'set-state' interface provided by clockevents core, the earlier 'set-mode' interface is marked obsolete now. This also enables us to implement callbacks for new states of clockevent devices, for example: ONESHOT_STOPPED. We aren't writing zero twice on the control register for shutdown or resume state now. Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
154 lines
4.2 KiB
C
154 lines
4.2 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 <linux/clockchips.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <mach/hardware.h>
|
|
#include <asm/mach/time.h>
|
|
#include <mach/netx-regs.h>
|
|
|
|
#define NETX_CLOCK_FREQ 100000000
|
|
#define NETX_LATCH DIV_ROUND_CLOSEST(NETX_CLOCK_FREQ, HZ)
|
|
|
|
#define TIMER_CLOCKEVENT 0
|
|
#define TIMER_CLOCKSOURCE 1
|
|
|
|
static inline void timer_shutdown(struct clock_event_device *evt)
|
|
{
|
|
/* disable timer */
|
|
writel(0, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
|
|
}
|
|
|
|
static int netx_shutdown(struct clock_event_device *evt)
|
|
{
|
|
timer_shutdown(evt);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int netx_set_oneshot(struct clock_event_device *evt)
|
|
{
|
|
u32 tmode = NETX_GPIO_COUNTER_CTRL_IRQ_EN | NETX_GPIO_COUNTER_CTRL_RUN;
|
|
|
|
timer_shutdown(evt);
|
|
writel(0, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKEVENT));
|
|
writel(tmode, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int netx_set_periodic(struct clock_event_device *evt)
|
|
{
|
|
u32 tmode = NETX_GPIO_COUNTER_CTRL_RST_EN |
|
|
NETX_GPIO_COUNTER_CTRL_IRQ_EN | NETX_GPIO_COUNTER_CTRL_RUN;
|
|
|
|
timer_shutdown(evt);
|
|
writel(NETX_LATCH, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKEVENT));
|
|
writel(tmode, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int netx_set_next_event(unsigned long evt,
|
|
struct clock_event_device *clk)
|
|
{
|
|
writel(0 - evt, NETX_GPIO_COUNTER_CURRENT(TIMER_CLOCKEVENT));
|
|
return 0;
|
|
}
|
|
|
|
static struct clock_event_device netx_clockevent = {
|
|
.name = "netx-timer" __stringify(TIMER_CLOCKEVENT),
|
|
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
|
|
.set_next_event = netx_set_next_event,
|
|
.set_state_shutdown = netx_shutdown,
|
|
.set_state_periodic = netx_set_periodic,
|
|
.set_state_oneshot = netx_set_oneshot,
|
|
.tick_resume = netx_shutdown,
|
|
};
|
|
|
|
/*
|
|
* IRQ handler for the timer
|
|
*/
|
|
static irqreturn_t
|
|
netx_timer_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct clock_event_device *evt = &netx_clockevent;
|
|
|
|
/* acknowledge interrupt */
|
|
writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
|
|
|
|
evt->event_handler(evt);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static struct irqaction netx_timer_irq = {
|
|
.name = "NetX Timer Tick",
|
|
.flags = IRQF_TIMER | IRQF_IRQPOLL,
|
|
.handler = netx_timer_interrupt,
|
|
};
|
|
|
|
/*
|
|
* Set up timer interrupt
|
|
*/
|
|
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(NETX_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(TIMER_CLOCKSOURCE));
|
|
writel(0, NETX_GPIO_COUNTER_CURRENT(TIMER_CLOCKSOURCE));
|
|
writel(0xffffffff, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKSOURCE));
|
|
|
|
writel(NETX_GPIO_COUNTER_CTRL_RUN,
|
|
NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKSOURCE));
|
|
|
|
clocksource_mmio_init(NETX_GPIO_COUNTER_CURRENT(TIMER_CLOCKSOURCE),
|
|
"netx_timer", NETX_CLOCK_FREQ, 200, 32, clocksource_mmio_readl_up);
|
|
|
|
/* with max_delta_ns >= delta2ns(0x800) the system currently runs fine.
|
|
* Adding some safety ... */
|
|
netx_clockevent.cpumask = cpumask_of(0);
|
|
clockevents_config_and_register(&netx_clockevent, NETX_CLOCK_FREQ,
|
|
0xa00, 0xfffffffe);
|
|
}
|