arch/microblaze/kernel/timer.c - linux - Git at Google

 /*
  * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
  * Copyright (C) 2007-2009 PetaLogix
  * Copyright (C) 2006 Atmark Techno, Inc.
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License. See the file "COPYING" in the main directory of this archive
  * for more details.
  */

 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/param.h>
 #include <linux/interrupt.h>
 #include <linux/profile.h>
 #include <linux/irq.h>
 #include <linux/delay.h>
 #include <linux/sched.h>
 #include <linux/spinlock.h>
 #include <linux/err.h>
 #include <linux/clk.h>
 #include <linux/clocksource.h>
 #include <linux/clockchips.h>
 #include <linux/io.h>
 #include <linux/bug.h>
 #include <asm/cpuinfo.h>
 #include <asm/setup.h>
 #include <asm/prom.h>
 #include <asm/irq.h>
 #include <linux/cnt32_to_63.h>

 #ifdef CONFIG_SELFMOD_TIMER
 #include <asm/selfmod.h>
 #define TIMER_BASE	BARRIER_BASE_ADDR
 #else
 static unsigned int timer_baseaddr;
 #define TIMER_BASE	timer_baseaddr
 #endif

 static unsigned int freq_div_hz;
 static unsigned int timer_clock_freq;

 #define TCSR0	(0x00)
 #define TLR0	(0x04)
 #define TCR0	(0x08)
 #define TCSR1	(0x10)
 #define TLR1	(0x14)
 #define TCR1	(0x18)

 #define TCSR_MDT	(1<<0)
 #define TCSR_UDT	(1<<1)
 #define TCSR_GENT	(1<<2)
 #define TCSR_CAPT	(1<<3)
 #define TCSR_ARHT	(1<<4)
 #define TCSR_LOAD	(1<<5)
 #define TCSR_ENIT	(1<<6)
 #define TCSR_ENT	(1<<7)
 #define TCSR_TINT	(1<<8)
 #define TCSR_PWMA	(1<<9)
 #define TCSR_ENALL	(1<<10)

 static inline void microblaze_timer0_stop(void)
 {
 	out_be32(TIMER_BASE + TCSR0, in_be32(TIMER_BASE + TCSR0) & ~TCSR_ENT);
 }

 static inline void microblaze_timer0_start_periodic(unsigned long load_val)
 {
 	if (!load_val)
 		load_val = 1;
 	out_be32(TIMER_BASE + TLR0, load_val); /* loading value to timer reg */

 	/* load the initial value */
 	out_be32(TIMER_BASE + TCSR0, TCSR_LOAD);

 	/* see timer data sheet for detail
 	 * !ENALL - don't enable 'em all
 	 * !PWMA - disable pwm
 	 * TINT - clear interrupt status
 	 * ENT- enable timer itself
 	 * ENIT - enable interrupt
 	 * !LOAD - clear the bit to let go
 	 * ARHT - auto reload
 	 * !CAPT - no external trigger
 	 * !GENT - no external signal
 	 * UDT - set the timer as down counter
 	 * !MDT0 - generate mode
 	 */
 	out_be32(TIMER_BASE + TCSR0,
 			TCSR_TINT|TCSR_ENIT|TCSR_ENT|TCSR_ARHT|TCSR_UDT);
 }

 static inline void microblaze_timer0_start_oneshot(unsigned long load_val)
 {
 	if (!load_val)
 		load_val = 1;
 	out_be32(TIMER_BASE + TLR0, load_val); /* loading value to timer reg */

 	/* load the initial value */
 	out_be32(TIMER_BASE + TCSR0, TCSR_LOAD);

 	out_be32(TIMER_BASE + TCSR0,
 			TCSR_TINT|TCSR_ENIT|TCSR_ENT|TCSR_ARHT|TCSR_UDT);
 }

 static int microblaze_timer_set_next_event(unsigned long delta,
 					struct clock_event_device *dev)
 {
 	pr_debug("%s: next event, delta %x\n", __func__, (u32)delta);
 	microblaze_timer0_start_oneshot(delta);
 	return 0;
 }

 static void microblaze_timer_set_mode(enum clock_event_mode mode,
 				struct clock_event_device *evt)
 {
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
 		pr_info("%s: periodic\n", __func__);
 		microblaze_timer0_start_periodic(freq_div_hz);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
 		pr_info("%s: oneshot\n", __func__);
 		break;
 	case CLOCK_EVT_MODE_UNUSED:
 		pr_info("%s: unused\n", __func__);
 		break;
 	case CLOCK_EVT_MODE_SHUTDOWN:
 		pr_info("%s: shutdown\n", __func__);
 		microblaze_timer0_stop();
 		break;
 	case CLOCK_EVT_MODE_RESUME:
 		pr_info("%s: resume\n", __func__);
 		break;
 	}
 }

 static struct clock_event_device clockevent_microblaze_timer = {
 	.name		= "microblaze_clockevent",
 	.features       = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
 	.shift		= 8,
 	.rating		= 300,
 	.set_next_event	= microblaze_timer_set_next_event,
 	.set_mode	= microblaze_timer_set_mode,
 };

 static inline void timer_ack(void)
 {
 	out_be32(TIMER_BASE + TCSR0, in_be32(TIMER_BASE + TCSR0));
 }

 static irqreturn_t timer_interrupt(int irq, void *dev_id)
 {
 	struct clock_event_device *evt = &clockevent_microblaze_timer;
 #ifdef CONFIG_HEART_BEAT
 	heartbeat();
 #endif
 	timer_ack();
 	evt->event_handler(evt);
 	return IRQ_HANDLED;
 }

 static struct irqaction timer_irqaction = {
 	.handler = timer_interrupt,
 	.flags = IRQF_DISABLED | IRQF_TIMER,
 	.name = "timer",
 	.dev_id = &clockevent_microblaze_timer,
 };

 static __init void microblaze_clockevent_init(void)
 {
 	clockevent_microblaze_timer.mult =
 		div_sc(timer_clock_freq, NSEC_PER_SEC,
 				clockevent_microblaze_timer.shift);
 	clockevent_microblaze_timer.max_delta_ns =
 		clockevent_delta2ns((u32)~0, &clockevent_microblaze_timer);
 	clockevent_microblaze_timer.min_delta_ns =
 		clockevent_delta2ns(1, &clockevent_microblaze_timer);
 	clockevent_microblaze_timer.cpumask = cpumask_of(0);
 	clockevents_register_device(&clockevent_microblaze_timer);
 }

 static cycle_t microblaze_read(struct clocksource *cs)
 {
 	/* reading actual value of timer 1 */
 	return (cycle_t) (in_be32(TIMER_BASE + TCR1));
 }

 static struct timecounter microblaze_tc = {
 	.cc = NULL,
 };

 static cycle_t microblaze_cc_read(const struct cyclecounter *cc)
 {
 	return microblaze_read(NULL);
 }

 static struct cyclecounter microblaze_cc = {
 	.read = microblaze_cc_read,
 	.mask = CLOCKSOURCE_MASK(32),
 	.shift = 8,
 };

 static int __init init_microblaze_timecounter(void)
 {
 	microblaze_cc.mult = div_sc(timer_clock_freq, NSEC_PER_SEC,
 				microblaze_cc.shift);

 	timecounter_init(&microblaze_tc, &microblaze_cc, sched_clock());

 	return 0;
 }

 static struct clocksource clocksource_microblaze = {
 	.name		= "microblaze_clocksource",
 	.rating		= 300,
 	.read		= microblaze_read,
 	.mask		= CLOCKSOURCE_MASK(32),
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };

 static int __init microblaze_clocksource_init(void)
 {
 	if (clocksource_register_hz(&clocksource_microblaze, timer_clock_freq))
 		panic("failed to register clocksource");

 	/* stop timer1 */
 	out_be32(TIMER_BASE + TCSR1, in_be32(TIMER_BASE + TCSR1) & ~TCSR_ENT);
 	/* start timer1 - up counting without interrupt */
 	out_be32(TIMER_BASE + TCSR1, TCSR_TINT|TCSR_ENT|TCSR_ARHT);

 	/* register timecounter - for ftrace support */
 	init_microblaze_timecounter();
 	return 0;
 }

 /*
  * We have to protect accesses before timer initialization
  * and return 0 for sched_clock function below.
  */
 static int timer_initialized;

 void __init time_init(void)
 {
 	u32 irq;
 	u32 timer_num = 1;
 	struct device_node *timer = NULL;
 	const void *prop;
 #ifdef CONFIG_SELFMOD_TIMER
 	unsigned int timer_baseaddr = 0;
 	int arr_func[] = {
 				(int)&microblaze_read,
 				(int)&timer_interrupt,
 				(int)&microblaze_clocksource_init,
 				(int)&microblaze_timer_set_mode,
 				(int)&microblaze_timer_set_next_event,
 				0
 			};
 #endif
 	prop = of_get_property(of_chosen, "system-timer", NULL);
 	if (prop)
 		timer = of_find_node_by_phandle(be32_to_cpup(prop));
 	else
 		pr_info("No chosen timer found, using default\n");

 	if (!timer)
 		timer = of_find_compatible_node(NULL, NULL,
 						"xlnx,xps-timer-1.00.a");
 	BUG_ON(!timer);

 	timer_baseaddr = be32_to_cpup(of_get_property(timer, "reg", NULL));
 	timer_baseaddr = (unsigned long) ioremap(timer_baseaddr, PAGE_SIZE);
 	irq = irq_of_parse_and_map(timer, 0);
 	timer_num = be32_to_cpup(of_get_property(timer,
 						"xlnx,one-timer-only", NULL));
 	if (timer_num) {
 		pr_emerg("Please   enable two timers in HW\n");
 		BUG();
 	}

 #ifdef CONFIG_SELFMOD_TIMER
 	selfmod_function((int *) arr_func, timer_baseaddr);
 #endif
 	pr_info("%s #0 at 0x%08x, irq=%d\n",
 		timer->name, timer_baseaddr, irq);

 	/* If there is clock-frequency property than use it */
 	prop = of_get_property(timer, "clock-frequency", NULL);
 	if (prop)
 		timer_clock_freq = be32_to_cpup(prop);
 	else
 		timer_clock_freq = cpuinfo.cpu_clock_freq;

 	freq_div_hz = timer_clock_freq / HZ;

 	setup_irq(irq, &timer_irqaction);
 #ifdef CONFIG_HEART_BEAT
 	setup_heartbeat();
 #endif
 	microblaze_clocksource_init();
 	microblaze_clockevent_init();
 	timer_initialized = 1;
 }

 unsigned long long notrace sched_clock(void)
 {
 	if (timer_initialized) {
 		struct clocksource *cs = &clocksource_microblaze;

 		cycle_t cyc = cnt32_to_63(cs->read(NULL)) & LLONG_MAX;
 		return clocksource_cyc2ns(cyc, cs->mult, cs->shift);
 	}
 	return 0;
 }
	/*
	* Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
	* Copyright (C) 2007-2009 PetaLogix
	* Copyright (C) 2006 Atmark Techno, Inc.
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*/

	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/param.h>
	#include <linux/interrupt.h>
	#include <linux/profile.h>
	#include <linux/irq.h>
	#include <linux/delay.h>
	#include <linux/sched.h>
	#include <linux/spinlock.h>
	#include <linux/err.h>
	#include <linux/clk.h>
	#include <linux/clocksource.h>
	#include <linux/clockchips.h>
	#include <linux/io.h>
	#include <linux/bug.h>
	#include <asm/cpuinfo.h>
	#include <asm/setup.h>
	#include <asm/prom.h>
	#include <asm/irq.h>
	#include <linux/cnt32_to_63.h>

	#ifdef CONFIG_SELFMOD_TIMER
	#include <asm/selfmod.h>
	#define TIMER_BASE BARRIER_BASE_ADDR
	#else
	static unsigned int timer_baseaddr;
	#define TIMER_BASE timer_baseaddr
	#endif

	static unsigned int freq_div_hz;
	static unsigned int timer_clock_freq;

	#define TCSR0 (0x00)
	#define TLR0 (0x04)
	#define TCR0 (0x08)
	#define TCSR1 (0x10)
	#define TLR1 (0x14)
	#define TCR1 (0x18)

	#define TCSR_MDT (1<<0)
	#define TCSR_UDT (1<<1)
	#define TCSR_GENT (1<<2)
	#define TCSR_CAPT (1<<3)
	#define TCSR_ARHT (1<<4)
	#define TCSR_LOAD (1<<5)
	#define TCSR_ENIT (1<<6)
	#define TCSR_ENT (1<<7)
	#define TCSR_TINT (1<<8)
	#define TCSR_PWMA (1<<9)
	#define TCSR_ENALL (1<<10)

	static inline void microblaze_timer0_stop(void)
	{
	out_be32(TIMER_BASE + TCSR0, in_be32(TIMER_BASE + TCSR0) & ~TCSR_ENT);
	}

	static inline void microblaze_timer0_start_periodic(unsigned long load_val)
	{
	if (!load_val)
	load_val = 1;
	out_be32(TIMER_BASE + TLR0, load_val); /* loading value to timer reg */

	/* load the initial value */
	out_be32(TIMER_BASE + TCSR0, TCSR_LOAD);

	/* see timer data sheet for detail
	* !ENALL - don't enable 'em all
	* !PWMA - disable pwm
	* TINT - clear interrupt status
	* ENT- enable timer itself
	* ENIT - enable interrupt
	* !LOAD - clear the bit to let go
	* ARHT - auto reload
	* !CAPT - no external trigger
	* !GENT - no external signal
	* UDT - set the timer as down counter
	* !MDT0 - generate mode
	*/
	out_be32(TIMER_BASE + TCSR0,
	TCSR_TINT\|TCSR_ENIT\|TCSR_ENT\|TCSR_ARHT\|TCSR_UDT);
	}

	static inline void microblaze_timer0_start_oneshot(unsigned long load_val)
	{
	if (!load_val)
	load_val = 1;
	out_be32(TIMER_BASE + TLR0, load_val); /* loading value to timer reg */

	/* load the initial value */
	out_be32(TIMER_BASE + TCSR0, TCSR_LOAD);

	out_be32(TIMER_BASE + TCSR0,
	TCSR_TINT\|TCSR_ENIT\|TCSR_ENT\|TCSR_ARHT\|TCSR_UDT);
	}

	static int microblaze_timer_set_next_event(unsigned long delta,
	struct clock_event_device *dev)
	{
	pr_debug("%s: next event, delta %x\n", __func__, (u32)delta);
	microblaze_timer0_start_oneshot(delta);
	return 0;
	}

	static void microblaze_timer_set_mode(enum clock_event_mode mode,
	struct clock_event_device *evt)
	{
	switch (mode) {
	case CLOCK_EVT_MODE_PERIODIC:
	pr_info("%s: periodic\n", __func__);
	microblaze_timer0_start_periodic(freq_div_hz);
	break;
	case CLOCK_EVT_MODE_ONESHOT:
	pr_info("%s: oneshot\n", __func__);
	break;
	case CLOCK_EVT_MODE_UNUSED:
	pr_info("%s: unused\n", __func__);
	break;
	case CLOCK_EVT_MODE_SHUTDOWN:
	pr_info("%s: shutdown\n", __func__);
	microblaze_timer0_stop();
	break;
	case CLOCK_EVT_MODE_RESUME:
	pr_info("%s: resume\n", __func__);
	break;
	}
	}

	static struct clock_event_device clockevent_microblaze_timer = {
	.name = "microblaze_clockevent",
	.features = CLOCK_EVT_FEAT_ONESHOT \| CLOCK_EVT_FEAT_PERIODIC,
	.shift = 8,
	.rating = 300,
	.set_next_event = microblaze_timer_set_next_event,
	.set_mode = microblaze_timer_set_mode,
	};

	static inline void timer_ack(void)
	{
	out_be32(TIMER_BASE + TCSR0, in_be32(TIMER_BASE + TCSR0));
	}

	static irqreturn_t timer_interrupt(int irq, void *dev_id)
	{
	struct clock_event_device *evt = &clockevent_microblaze_timer;
	#ifdef CONFIG_HEART_BEAT
	heartbeat();
	#endif
	timer_ack();
	evt->event_handler(evt);
	return IRQ_HANDLED;
	}

	static struct irqaction timer_irqaction = {
	.handler = timer_interrupt,
	.flags = IRQF_DISABLED \| IRQF_TIMER,
	.name = "timer",
	.dev_id = &clockevent_microblaze_timer,
	};

	static __init void microblaze_clockevent_init(void)
	{
	clockevent_microblaze_timer.mult =
	div_sc(timer_clock_freq, NSEC_PER_SEC,
	clockevent_microblaze_timer.shift);
	clockevent_microblaze_timer.max_delta_ns =
	clockevent_delta2ns((u32)~0, &clockevent_microblaze_timer);
	clockevent_microblaze_timer.min_delta_ns =
	clockevent_delta2ns(1, &clockevent_microblaze_timer);
	clockevent_microblaze_timer.cpumask = cpumask_of(0);
	clockevents_register_device(&clockevent_microblaze_timer);
	}

	static cycle_t microblaze_read(struct clocksource *cs)
	{
	/* reading actual value of timer 1 */
	return (cycle_t) (in_be32(TIMER_BASE + TCR1));
	}

	static struct timecounter microblaze_tc = {
	.cc = NULL,
	};

	static cycle_t microblaze_cc_read(const struct cyclecounter *cc)
	{
	return microblaze_read(NULL);
	}

	static struct cyclecounter microblaze_cc = {
	.read = microblaze_cc_read,
	.mask = CLOCKSOURCE_MASK(32),
	.shift = 8,
	};

	static int __init init_microblaze_timecounter(void)
	{
	microblaze_cc.mult = div_sc(timer_clock_freq, NSEC_PER_SEC,
	microblaze_cc.shift);

	timecounter_init(&microblaze_tc, &microblaze_cc, sched_clock());

	return 0;
	}

	static struct clocksource clocksource_microblaze = {
	.name = "microblaze_clocksource",
	.rating = 300,
	.read = microblaze_read,
	.mask = CLOCKSOURCE_MASK(32),
	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
	};

	static int __init microblaze_clocksource_init(void)
	{
	if (clocksource_register_hz(&clocksource_microblaze, timer_clock_freq))
	panic("failed to register clocksource");

	/* stop timer1 */
	out_be32(TIMER_BASE + TCSR1, in_be32(TIMER_BASE + TCSR1) & ~TCSR_ENT);
	/* start timer1 - up counting without interrupt */
	out_be32(TIMER_BASE + TCSR1, TCSR_TINT\|TCSR_ENT\|TCSR_ARHT);

	/* register timecounter - for ftrace support */
	init_microblaze_timecounter();
	return 0;
	}

	/*
	* We have to protect accesses before timer initialization
	* and return 0 for sched_clock function below.
	*/
	static int timer_initialized;

	void __init time_init(void)
	{
	u32 irq;
	u32 timer_num = 1;
	struct device_node *timer = NULL;
	const void *prop;
	#ifdef CONFIG_SELFMOD_TIMER
	unsigned int timer_baseaddr = 0;
	int arr_func[] = {
	(int)&microblaze_read,
	(int)&timer_interrupt,
	(int)&microblaze_clocksource_init,
	(int)&microblaze_timer_set_mode,
	(int)&microblaze_timer_set_next_event,
	0
	};
	#endif
	prop = of_get_property(of_chosen, "system-timer", NULL);
	if (prop)
	timer = of_find_node_by_phandle(be32_to_cpup(prop));
	else
	pr_info("No chosen timer found, using default\n");

	if (!timer)
	timer = of_find_compatible_node(NULL, NULL,
	"xlnx,xps-timer-1.00.a");
	BUG_ON(!timer);

	timer_baseaddr = be32_to_cpup(of_get_property(timer, "reg", NULL));
	timer_baseaddr = (unsigned long) ioremap(timer_baseaddr, PAGE_SIZE);
	irq = irq_of_parse_and_map(timer, 0);
	timer_num = be32_to_cpup(of_get_property(timer,
	"xlnx,one-timer-only", NULL));
	if (timer_num) {
	pr_emerg("Please enable two timers in HW\n");
	BUG();
	}

	#ifdef CONFIG_SELFMOD_TIMER
	selfmod_function((int *) arr_func, timer_baseaddr);
	#endif
	pr_info("%s #0 at 0x%08x, irq=%d\n",
	timer->name, timer_baseaddr, irq);

	/* If there is clock-frequency property than use it */
	prop = of_get_property(timer, "clock-frequency", NULL);
	if (prop)
	timer_clock_freq = be32_to_cpup(prop);
	else
	timer_clock_freq = cpuinfo.cpu_clock_freq;

	freq_div_hz = timer_clock_freq / HZ;

	setup_irq(irq, &timer_irqaction);
	#ifdef CONFIG_HEART_BEAT
	setup_heartbeat();
	#endif
	microblaze_clocksource_init();
	microblaze_clockevent_init();
	timer_initialized = 1;
	}

	unsigned long long notrace sched_clock(void)
	{
	if (timer_initialized) {
	struct clocksource *cs = &clocksource_microblaze;

	cycle_t cyc = cnt32_to_63(cs->read(NULL)) & LLONG_MAX;
	return clocksource_cyc2ns(cyc, cs->mult, cs->shift);
	}
	return 0;
	}