netx: add support for clockevents

This is based on a patch by Luotao Fu <lfu@pengutronix.de>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Luotao Fu <lfu@pengutronix.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Uwe Kleine-König 2008-12-09 21:57:24 +01:00
parent 21edecd355
commit 2fcfe6b872
2 changed files with 68 additions and 1 deletions

View File

@ -287,6 +287,7 @@ config ARCH_FOOTBRIDGE
config ARCH_NETX
bool "Hilscher NetX based"
select ARM_VIC
select GENERIC_CLOCKEVENTS
select GENERIC_TIME
help
This enables support for systems based on the Hilscher NetX Soc

View File

@ -21,25 +21,80 @@
#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 TIMER_CLOCKEVENT 0
#define TIMER_CLOCKSOURCE 1
static void netx_set_mode(enum clock_event_mode mode,
struct clock_event_device *clk)
{
u32 tmode;
/* disable timer */
writel(0, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
writel(LATCH, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKEVENT));
tmode = NETX_GPIO_COUNTER_CTRL_RST_EN |
NETX_GPIO_COUNTER_CTRL_IRQ_EN |
NETX_GPIO_COUNTER_CTRL_RUN;
break;
case CLOCK_EVT_MODE_ONESHOT:
writel(0, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKEVENT));
tmode = NETX_GPIO_COUNTER_CTRL_IRQ_EN |
NETX_GPIO_COUNTER_CTRL_RUN;
break;
default:
WARN(1, "%s: unhandled mode %d\n", __func__, mode);
/* fall through */
case CLOCK_EVT_MODE_SHUTDOWN:
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_RESUME:
tmode = 0;
break;
}
writel(tmode, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
}
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),
.shift = 32,
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
.set_next_event = netx_set_next_event,
.set_mode = netx_set_mode,
};
/*
* IRQ handler for the timer
*/
static irqreturn_t
netx_timer_interrupt(int irq, void *dev_id)
{
timer_tick();
struct clock_event_device *evt = &netx_clockevent;
/* acknowledge interrupt */
writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
evt->event_handler(evt);
return IRQ_HANDLED;
}
@ -99,6 +154,17 @@ static void __init netx_timer_init(void)
clocksource_netx.mult =
clocksource_hz2mult(CLOCK_TICK_RATE, clocksource_netx.shift);
clocksource_register(&clocksource_netx);
netx_clockevent.mult = div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC,
netx_clockevent.shift);
netx_clockevent.max_delta_ns =
clockevent_delta2ns(0xfffffffe, &netx_clockevent);
/* with max_delta_ns >= delta2ns(0x800) the system currently runs fine.
* Adding some safety ... */
netx_clockevent.min_delta_ns =
clockevent_delta2ns(0xa00, &netx_clockevent);
netx_clockevent.cpumask = cpumask_of_cpu(0);
clockevents_register_device(&netx_clockevent);
}
struct sys_timer netx_timer = {