64 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			64 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * ip30-timer.c: Clocksource/clockevent support for the
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|  *               HEART chip in SGI Octane (IP30) systems.
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|  *
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|  * Copyright (C) 2004-2007 Stanislaw Skowronek <skylark@unaligned.org>
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|  * Copyright (C) 2009 Johannes Dickgreber <tanzy@gmx.de>
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|  * Copyright (C) 2011 Joshua Kinard <kumba@gentoo.org>
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|  */
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| 
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| #include <linux/clocksource.h>
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| #include <linux/cpumask.h>
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| #include <linux/init.h>
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| #include <linux/kernel.h>
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| #include <linux/percpu.h>
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| #include <linux/sched_clock.h>
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| 
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| #include <asm/time.h>
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| #include <asm/cevt-r4k.h>
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| #include <asm/sgi/heart.h>
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| 
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| static u64 ip30_heart_counter_read(struct clocksource *cs)
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| {
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| 	return heart_read(&heart_regs->count);
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| }
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| 
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| struct clocksource ip30_heart_clocksource = {
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| 	.name	= "HEART",
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| 	.rating	= 400,
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| 	.read	= ip30_heart_counter_read,
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| 	.mask	= CLOCKSOURCE_MASK(52),
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| 	.flags	= (CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_VALID_FOR_HRES),
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| };
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| 
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| static u64 notrace ip30_heart_read_sched_clock(void)
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| {
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| 	return heart_read(&heart_regs->count);
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| }
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| 
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| static void __init ip30_heart_clocksource_init(void)
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| {
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| 	struct clocksource *cs = &ip30_heart_clocksource;
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| 
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| 	clocksource_register_hz(cs, HEART_CYCLES_PER_SEC);
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| 
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| 	sched_clock_register(ip30_heart_read_sched_clock, 52,
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| 			     HEART_CYCLES_PER_SEC);
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| }
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| 
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| void __init plat_time_init(void)
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| {
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| 	int irq = get_c0_compare_int();
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| 
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| 	cp0_timer_irq_installed = 1;
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| 	c0_compare_irqaction.percpu_dev_id = &mips_clockevent_device;
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| 	c0_compare_irqaction.flags &= ~IRQF_SHARED;
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| 	irq_set_handler(irq, handle_percpu_devid_irq);
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| 	irq_set_percpu_devid(irq);
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| 	setup_percpu_irq(irq, &c0_compare_irqaction);
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| 	enable_percpu_irq(irq, IRQ_TYPE_NONE);
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| 
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| 	ip30_heart_clocksource_init();
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| }
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