[deliverable/linux.git] / arch / arm / mach-netx / time.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);
}
Commit	Line	Data
	1	/*
	2	* arch/arm/mach-netx/time.c
	3	*
	4	* Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2
	8	* as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	18	*/
	19
	20	#include <linux/init.h>
	21	#include <linux/interrupt.h>
	22	#include <linux/irq.h>
	23	#include <linux/clocksource.h>
	24	#include <linux/clockchips.h>
	25	#include <linux/io.h>
	26
	27	#include <mach/hardware.h>
	28	#include <asm/mach/time.h>
	29	#include <mach/netx-regs.h>
	30
	31	#define NETX_CLOCK_FREQ 100000000
	32	#define NETX_LATCH DIV_ROUND_CLOSEST(NETX_CLOCK_FREQ, HZ)
	33
	34	#define TIMER_CLOCKEVENT 0
	35	#define TIMER_CLOCKSOURCE 1
	36
	37	static inline void timer_shutdown(struct clock_event_device *evt)
	38	{
	39	/* disable timer */
	40	writel(0, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
	41	}
	42
	43	static int netx_shutdown(struct clock_event_device *evt)
	44	{
	45	timer_shutdown(evt);
	46
	47	return 0;
	48	}
	49
	50	static int netx_set_oneshot(struct clock_event_device *evt)
	51	{
	52	u32 tmode = NETX_GPIO_COUNTER_CTRL_IRQ_EN \| NETX_GPIO_COUNTER_CTRL_RUN;
	53
	54	timer_shutdown(evt);
	55	writel(0, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKEVENT));
	56	writel(tmode, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
	57
	58	return 0;
	59	}
	60
	61	static int netx_set_periodic(struct clock_event_device *evt)
	62	{
	63	u32 tmode = NETX_GPIO_COUNTER_CTRL_RST_EN \|
	64	NETX_GPIO_COUNTER_CTRL_IRQ_EN \| NETX_GPIO_COUNTER_CTRL_RUN;
	65
	66	timer_shutdown(evt);
	67	writel(NETX_LATCH, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKEVENT));
	68	writel(tmode, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
	69
	70	return 0;
	71	}
	72
	73	static int netx_set_next_event(unsigned long evt,
	74	struct clock_event_device *clk)
	75	{
	76	writel(0 - evt, NETX_GPIO_COUNTER_CURRENT(TIMER_CLOCKEVENT));
	77	return 0;
	78	}
	79
	80	static struct clock_event_device netx_clockevent = {
	81	.name = "netx-timer" __stringify(TIMER_CLOCKEVENT),
	82	.features = CLOCK_EVT_FEAT_PERIODIC \| CLOCK_EVT_FEAT_ONESHOT,
	83	.set_next_event = netx_set_next_event,
	84	.set_state_shutdown = netx_shutdown,
	85	.set_state_periodic = netx_set_periodic,
	86	.set_state_oneshot = netx_set_oneshot,
	87	.tick_resume = netx_shutdown,
	88	};
	89
	90	/*
	91	* IRQ handler for the timer
	92	*/
	93	static irqreturn_t
	94	netx_timer_interrupt(int irq, void *dev_id)
	95	{
	96	struct clock_event_device *evt = &netx_clockevent;
	97
	98	/* acknowledge interrupt */
	99	writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
	100
	101	evt->event_handler(evt);
	102
	103	return IRQ_HANDLED;
	104	}
	105
	106	static struct irqaction netx_timer_irq = {
	107	.name = "NetX Timer Tick",
	108	.flags = IRQF_TIMER \| IRQF_IRQPOLL,
	109	.handler = netx_timer_interrupt,
	110	};
	111
	112	/*
	113	* Set up timer interrupt
	114	*/
	115	void __init netx_timer_init(void)
	116	{
	117	/* disable timer initially */
	118	writel(0, NETX_GPIO_COUNTER_CTRL(0));
	119
	120	/* Reset the timer value to zero */
	121	writel(0, NETX_GPIO_COUNTER_CURRENT(0));
	122
	123	writel(NETX_LATCH, NETX_GPIO_COUNTER_MAX(0));
	124
	125	/* acknowledge interrupt */
	126	writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
	127
	128	/* Enable the interrupt in the specific timer
	129	* register and start timer
	130	*/
	131	writel(COUNTER_BIT(0), NETX_GPIO_IRQ_ENABLE);
	132	writel(NETX_GPIO_COUNTER_CTRL_IRQ_EN \| NETX_GPIO_COUNTER_CTRL_RUN,
	133	NETX_GPIO_COUNTER_CTRL(0));
	134
	135	setup_irq(NETX_IRQ_TIMER0, &netx_timer_irq);
	136
	137	/* Setup timer one for clocksource */
	138	writel(0, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKSOURCE));
	139	writel(0, NETX_GPIO_COUNTER_CURRENT(TIMER_CLOCKSOURCE));
	140	writel(0xffffffff, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKSOURCE));
	141
	142	writel(NETX_GPIO_COUNTER_CTRL_RUN,
	143	NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKSOURCE));
	144
	145	clocksource_mmio_init(NETX_GPIO_COUNTER_CURRENT(TIMER_CLOCKSOURCE),
	146	"netx_timer", NETX_CLOCK_FREQ, 200, 32, clocksource_mmio_readl_up);
	147
	148	/* with max_delta_ns >= delta2ns(0x800) the system currently runs fine.
	149	* Adding some safety ... */
	150	netx_clockevent.cpumask = cpumask_of(0);
	151	clockevents_config_and_register(&netx_clockevent, NETX_CLOCK_FREQ,
	152	0xa00, 0xfffffffe);
	153	}