/* * System timer for CSR SiRFprimaII * * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company. * * Licensed under GPLv2 or later. */ #include <linux/kernel.h>#include <linux/interrupt.h>#include <linux/clockchips.h>#include <linux/clocksource.h>#include <linux/cpu.h>#include <linux/bitops.h>#include <linux/irq.h>#include <linux/clk.h>#include <linux/slab.h>#include <linux/of.h>#include <linux/of_irq.h>#include <linux/of_address.h>#include <linux/sched_clock.h>#include <asm/mach/time.h> #define SIRFSOC_TIMER_32COUNTER_0_CTRL			0x0000#define SIRFSOC_TIMER_32COUNTER_1_CTRL			0x0004#define SIRFSOC_TIMER_MATCH_0				0x0018#define SIRFSOC_TIMER_MATCH_1				0x001c#define SIRFSOC_TIMER_COUNTER_0				0x0048#define SIRFSOC_TIMER_COUNTER_1				0x004c#define SIRFSOC_TIMER_INTR_STATUS			0x0060#define SIRFSOC_TIMER_WATCHDOG_EN			0x0064#define SIRFSOC_TIMER_64COUNTER_CTRL			0x0068#define SIRFSOC_TIMER_64COUNTER_LO			0x006c#define SIRFSOC_TIMER_64COUNTER_HI			0x0070#define SIRFSOC_TIMER_64COUNTER_LOAD_LO			0x0074#define SIRFSOC_TIMER_64COUNTER_LOAD_HI			0x0078#define SIRFSOC_TIMER_64COUNTER_RLATCHED_LO		0x007c#define SIRFSOC_TIMER_64COUNTER_RLATCHED_HI		0x0080 #define SIRFSOC_TIMER_REG_CNT 6 static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {	SIRFSOC_TIMER_WATCHDOG_EN,	SIRFSOC_TIMER_32COUNTER_0_CTRL,	SIRFSOC_TIMER_32COUNTER_1_CTRL,	SIRFSOC_TIMER_64COUNTER_CTRL,	SIRFSOC_TIMER_64COUNTER_RLATCHED_LO,	SIRFSOC_TIMER_64COUNTER_RLATCHED_HI,}; static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT]; static void __iomem *sirfsoc_timer_base; /* disable count and interrupt */static inline void sirfsoc_timer_count_disable(int idx){	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) & ~0x7,		sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);} /* enable count and interrupt */static inline void sirfsoc_timer_count_enable(int idx){	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) | 0x7,		sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);} /* timer interrupt handler */static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id){	struct clock_event_device *ce = dev_id;	int cpu = smp_processor_id(); 	/* clear timer interrupt */	writel_relaxed(BIT(cpu), sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS); 	if (ce->mode == CLOCK_EVT_MODE_ONESHOT)		sirfsoc_timer_count_disable(cpu); 	ce->event_handler(ce); 	return IRQ_HANDLED;} /* read 64-bit timer counter */static cycle_t sirfsoc_timer_read(struct clocksource *cs){	u64 cycles; 	writel_relaxed((readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |			BIT(0)) & ~BIT(1), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL); 	cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_HI);	cycles = (cycles << 32) | readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_LO); 	return cycles;} static int sirfsoc_timer_set_next_event(unsigned long delta,	struct clock_event_device *ce){	int cpu = smp_processor_id(); 	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0 +		4 * cpu);	writel_relaxed(delta, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0 +		4 * cpu); 	/* enable the tick */	sirfsoc_timer_count_enable(cpu); 	return 0;} static void sirfsoc_timer_set_mode(enum clock_event_mode mode,	struct clock_event_device *ce){	switch (mode) {	case CLOCK_EVT_MODE_ONESHOT:		/* enable in set_next_event */		break;	default:		break;	} 	sirfsoc_timer_count_disable(smp_processor_id());} static void sirfsoc_clocksource_suspend(struct clocksource *cs){	int i; 	for (i = 0; i < SIRFSOC_TIMER_REG_CNT; i++)		sirfsoc_timer_reg_val[i] = readl_relaxed(sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);} static void sirfsoc_clocksource_resume(struct clocksource *cs){	int i; 	for (i = 0; i < SIRFSOC_TIMER_REG_CNT - 2; i++)		writel_relaxed(sirfsoc_timer_reg_val[i], sirfsoc_timer_base + sirfsoc_timer_reg_list[i]); 	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2],		sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1],		sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI); 	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |		BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);} static struct clock_event_device __percpu *sirfsoc_clockevent; static struct clocksource sirfsoc_clocksource = {	.name = "sirfsoc_clocksource",	.rating = 200,	.mask = CLOCKSOURCE_MASK(64),	.flags = CLOCK_SOURCE_IS_CONTINUOUS,	.read = sirfsoc_timer_read,	.suspend = sirfsoc_clocksource_suspend,	.resume = sirfsoc_clocksource_resume,}; static struct irqaction sirfsoc_timer_irq = {	.name = "sirfsoc_timer0",	.flags = IRQF_TIMER | IRQF_NOBALANCING,	.handler = sirfsoc_timer_interrupt,}; static struct irqaction sirfsoc_timer1_irq = {	.name = "sirfsoc_timer1",	.flags = IRQF_TIMER | IRQF_NOBALANCING,	.handler = sirfsoc_timer_interrupt,}; static int sirfsoc_local_timer_setup(struct clock_event_device *ce){	int cpu = smp_processor_id();	struct irqaction *action; 	if (cpu == 0)		action = &sirfsoc_timer_irq;	else		action = &sirfsoc_timer1_irq; 	ce->irq = action->irq;	ce->name = "local_timer";	ce->features = CLOCK_EVT_FEAT_ONESHOT;	ce->rating = 200;	ce->set_mode = sirfsoc_timer_set_mode;	ce->set_next_event = sirfsoc_timer_set_next_event;	clockevents_calc_mult_shift(ce, CLOCK_TICK_RATE, 60);	ce->max_delta_ns = clockevent_delta2ns(-2, ce);	ce->min_delta_ns = clockevent_delta2ns(2, ce);	ce->cpumask = cpumask_of(cpu); 	action->dev_id = ce;	BUG_ON(setup_irq(ce->irq, action));	irq_set_affinity(action->irq, cpumask_of(cpu)); 	clockevents_register_device(ce);	return 0;} static void sirfsoc_local_timer_stop(struct clock_event_device *ce){	int cpu = smp_processor_id(); 	sirfsoc_timer_count_disable(1); 	if (cpu == 0)		remove_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq);	else		remove_irq(sirfsoc_timer1_irq.irq, &sirfsoc_timer1_irq);} static int sirfsoc_cpu_notify(struct notifier_block *self,			      unsigned long action, void *hcpu){	/*	 * Grab cpu pointer in each case to avoid spurious	 * preemptible warnings	 */	switch (action & ~CPU_TASKS_FROZEN) {	case CPU_STARTING:		sirfsoc_local_timer_setup(this_cpu_ptr(sirfsoc_clockevent));		break;	case CPU_DYING:		sirfsoc_local_timer_stop(this_cpu_ptr(sirfsoc_clockevent));		break;	} 	return NOTIFY_OK;} static struct notifier_block sirfsoc_cpu_nb = {	.notifier_call = sirfsoc_cpu_notify,}; static void __init sirfsoc_clockevent_init(void){	sirfsoc_clockevent = alloc_percpu(struct clock_event_device);	BUG_ON(!sirfsoc_clockevent); 	BUG_ON(register_cpu_notifier(&sirfsoc_cpu_nb)); 	/* Immediately configure the timer on the boot CPU */	sirfsoc_local_timer_setup(this_cpu_ptr(sirfsoc_clockevent));} /* initialize the kernel jiffy timer source */static void __init sirfsoc_marco_timer_init(void){	unsigned long rate;	u32 timer_div;	struct clk *clk; 	/* timer's input clock is io clock */	clk = clk_get_sys("io", NULL); 	BUG_ON(IS_ERR(clk));	rate = clk_get_rate(clk); 	BUG_ON(rate < CLOCK_TICK_RATE);	BUG_ON(rate % CLOCK_TICK_RATE); 	/* Initialize the timer dividers */	timer_div = rate / CLOCK_TICK_RATE - 1;	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL);	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_1_CTRL); 	/* Initialize timer counters to 0 */	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |		BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0);	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_1); 	/* Clear all interrupts */	writel_relaxed(0xFFFF, sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS); 	BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, CLOCK_TICK_RATE)); 	sirfsoc_clockevent_init();} static void __init sirfsoc_of_timer_init(struct device_node *np){	sirfsoc_timer_base = of_iomap(np, 0);	if (!sirfsoc_timer_base)		panic("unable to map timer cpu registers\n"); 	sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);	if (!sirfsoc_timer_irq.irq)		panic("No irq passed for timer0 via DT\n"); 	sirfsoc_timer1_irq.irq = irq_of_parse_and_map(np, 1);	if (!sirfsoc_timer1_irq.irq)		panic("No irq passed for timer1 via DT\n"); 	sirfsoc_marco_timer_init();}CLOCKSOURCE_OF_DECLARE(sirfsoc_marco_timer, "sirf,marco-tick", sirfsoc_of_timer_init );