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	 2e8bac532f
			
		
	
	
		2e8bac532f
		
	
	
	
	
		
			
			The 32 bit sched_clock interface now supports 64 bits. Upgrade to the 64 bit function to allow us to remove the 32 bit registration interface. Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
		
			
				
	
	
		
			150 lines
		
	
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			150 lines
		
	
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Marvell Orion SoC timer handling.
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|  *
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|  * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
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|  *
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|  * This file is licensed under the terms of the GNU General Public
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|  * License version 2.  This program is licensed "as is" without any
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|  * warranty of any kind, whether express or implied.
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|  *
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|  * Timer 0 is used as free-running clocksource, while timer 1 is
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|  * used as clock_event_device.
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/bitops.h>
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| #include <linux/clk.h>
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| #include <linux/clockchips.h>
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| #include <linux/interrupt.h>
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| #include <linux/of_address.h>
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| #include <linux/of_irq.h>
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| #include <linux/spinlock.h>
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| #include <linux/sched_clock.h>
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| 
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| #define TIMER_CTRL		0x00
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| #define  TIMER0_EN		BIT(0)
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| #define  TIMER0_RELOAD_EN	BIT(1)
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| #define  TIMER1_EN		BIT(2)
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| #define  TIMER1_RELOAD_EN	BIT(3)
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| #define TIMER0_RELOAD		0x10
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| #define TIMER0_VAL		0x14
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| #define TIMER1_RELOAD		0x18
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| #define TIMER1_VAL		0x1c
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| 
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| #define ORION_ONESHOT_MIN	1
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| #define ORION_ONESHOT_MAX	0xfffffffe
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| 
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| static void __iomem *timer_base;
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| static DEFINE_SPINLOCK(timer_ctrl_lock);
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| 
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| /*
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|  * Thread-safe access to TIMER_CTRL register
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|  * (shared with watchdog timer)
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|  */
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| void orion_timer_ctrl_clrset(u32 clr, u32 set)
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| {
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| 	spin_lock(&timer_ctrl_lock);
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| 	writel((readl(timer_base + TIMER_CTRL) & ~clr) | set,
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| 		timer_base + TIMER_CTRL);
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| 	spin_unlock(&timer_ctrl_lock);
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| }
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| EXPORT_SYMBOL(orion_timer_ctrl_clrset);
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| 
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| /*
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|  * Free-running clocksource handling.
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|  */
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| static u64 notrace orion_read_sched_clock(void)
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| {
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| 	return ~readl(timer_base + TIMER0_VAL);
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| }
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| 
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| /*
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|  * Clockevent handling.
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|  */
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| static u32 ticks_per_jiffy;
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| 
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| static int orion_clkevt_next_event(unsigned long delta,
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| 				   struct clock_event_device *dev)
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| {
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| 	/* setup and enable one-shot timer */
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| 	writel(delta, timer_base + TIMER1_VAL);
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| 	orion_timer_ctrl_clrset(TIMER1_RELOAD_EN, TIMER1_EN);
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| 
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| 	return 0;
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| }
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| 
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| static void orion_clkevt_mode(enum clock_event_mode mode,
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| 			      struct clock_event_device *dev)
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| {
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| 	if (mode == CLOCK_EVT_MODE_PERIODIC) {
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| 		/* setup and enable periodic timer at 1/HZ intervals */
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| 		writel(ticks_per_jiffy - 1, timer_base + TIMER1_RELOAD);
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| 		writel(ticks_per_jiffy - 1, timer_base + TIMER1_VAL);
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| 		orion_timer_ctrl_clrset(0, TIMER1_RELOAD_EN | TIMER1_EN);
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| 	} else {
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| 		/* disable timer */
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| 		orion_timer_ctrl_clrset(TIMER1_RELOAD_EN | TIMER1_EN, 0);
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| 	}
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| }
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| 
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| static struct clock_event_device orion_clkevt = {
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| 	.name		= "orion_event",
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| 	.features	= CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
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| 	.shift		= 32,
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| 	.rating		= 300,
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| 	.set_next_event	= orion_clkevt_next_event,
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| 	.set_mode	= orion_clkevt_mode,
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| };
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| 
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| static irqreturn_t orion_clkevt_irq_handler(int irq, void *dev_id)
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| {
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| 	orion_clkevt.event_handler(&orion_clkevt);
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| 	return IRQ_HANDLED;
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| }
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| 
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| static struct irqaction orion_clkevt_irq = {
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| 	.name		= "orion_event",
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| 	.flags		= IRQF_TIMER,
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| 	.handler	= orion_clkevt_irq_handler,
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| };
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| 
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| static void __init orion_timer_init(struct device_node *np)
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| {
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| 	struct clk *clk;
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| 	int irq;
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| 
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| 	/* timer registers are shared with watchdog timer */
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| 	timer_base = of_iomap(np, 0);
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| 	if (!timer_base)
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| 		panic("%s: unable to map resource\n", np->name);
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| 
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| 	clk = of_clk_get(np, 0);
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| 	if (IS_ERR(clk))
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| 		panic("%s: unable to get clk\n", np->name);
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| 	clk_prepare_enable(clk);
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| 
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| 	/* we are only interested in timer1 irq */
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| 	irq = irq_of_parse_and_map(np, 1);
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| 	if (irq <= 0)
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| 		panic("%s: unable to parse timer1 irq\n", np->name);
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| 
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| 	/* setup timer0 as free-running clocksource */
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| 	writel(~0, timer_base + TIMER0_VAL);
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| 	writel(~0, timer_base + TIMER0_RELOAD);
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| 	orion_timer_ctrl_clrset(0, TIMER0_RELOAD_EN | TIMER0_EN);
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| 	clocksource_mmio_init(timer_base + TIMER0_VAL, "orion_clocksource",
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| 			      clk_get_rate(clk), 300, 32,
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| 			      clocksource_mmio_readl_down);
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| 	sched_clock_register(orion_read_sched_clock, 32, clk_get_rate(clk));
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| 
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| 	/* setup timer1 as clockevent timer */
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| 	if (setup_irq(irq, &orion_clkevt_irq))
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| 		panic("%s: unable to setup irq\n", np->name);
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| 
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| 	ticks_per_jiffy = (clk_get_rate(clk) + HZ/2) / HZ;
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| 	orion_clkevt.cpumask = cpumask_of(0);
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| 	orion_clkevt.irq = irq;
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| 	clockevents_config_and_register(&orion_clkevt, clk_get_rate(clk),
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| 					ORION_ONESHOT_MIN, ORION_ONESHOT_MAX);
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| }
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| CLOCKSOURCE_OF_DECLARE(orion_timer, "marvell,orion-timer", orion_timer_init);
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