152 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			152 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright 2001, 2002, 2003 MontaVista Software Inc.
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|  * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
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|  * Copyright (C) 2007 Ralf Baechle (ralf@linux-mips.org)
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|  *
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|  * Common time service routines for MIPS machines. See
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|  * Documents/MIPS/README.txt.
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|  *
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|  * This program is free software; you can redistribute  it and/or modify it
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|  * under  the terms of  the GNU General  Public License as published by the
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|  * Free Software Foundation;  either version 2 of the  License, or (at your
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|  * option) any later version.
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|  */
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| #include <linux/types.h>
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| #include <linux/kernel.h>
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| #include <linux/init.h>
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| #include <linux/sched.h>
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| #include <linux/param.h>
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| #include <linux/time.h>
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| #include <linux/timer.h>
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| #include <linux/smp.h>
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| #include <linux/kernel_stat.h>
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| #include <linux/spinlock.h>
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| #include <linux/interrupt.h>
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| 
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| #include <asm/bootinfo.h>
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| #include <asm/cpu.h>
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| #include <asm/time.h>
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| #include <asm/hardirq.h>
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| #include <asm/div64.h>
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| #include <asm/debug.h>
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| 
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| #include <int.h>
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| #include <cm.h>
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| 
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| static unsigned long cpj;
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| 
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| static cycle_t hpt_read(struct clocksource *cs)
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| {
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| 	return read_c0_count2();
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| }
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| 
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| static struct clocksource pnx_clocksource = {
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| 	.name		= "pnx8xxx",
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| 	.rating		= 200,
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| 	.read		= hpt_read,
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| 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
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| };
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| 
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| static irqreturn_t pnx8xxx_timer_interrupt(int irq, void *dev_id)
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| {
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| 	struct clock_event_device *c = dev_id;
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| 
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| 	/* clear MATCH, signal the event */
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| 	c->event_handler(c);
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| 
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| 	return IRQ_HANDLED;
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| }
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| 
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| static struct irqaction pnx8xxx_timer_irq = {
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| 	.handler	= pnx8xxx_timer_interrupt,
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| 	.flags		= IRQF_DISABLED | IRQF_PERCPU | IRQF_TIMER,
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| 	.name		= "pnx8xxx_timer",
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| };
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| 
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| static irqreturn_t monotonic_interrupt(int irq, void *dev_id)
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| {
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| 	/* Timer 2 clear interrupt */
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| 	write_c0_compare2(-1);
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| 	return IRQ_HANDLED;
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| }
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| 
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| static struct irqaction monotonic_irqaction = {
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| 	.handler = monotonic_interrupt,
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| 	.flags = IRQF_DISABLED | IRQF_TIMER,
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| 	.name = "Monotonic timer",
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| };
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| 
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| static int pnx8xxx_set_next_event(unsigned long delta,
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| 				struct clock_event_device *evt)
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| {
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| 	write_c0_compare(delta);
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| 	return 0;
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| }
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| 
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| static struct clock_event_device pnx8xxx_clockevent = {
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| 	.name		= "pnx8xxx_clockevent",
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| 	.features	= CLOCK_EVT_FEAT_ONESHOT,
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| 	.set_next_event = pnx8xxx_set_next_event,
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| };
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| 
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| static inline void timer_ack(void)
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| {
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| 	write_c0_compare(cpj);
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| }
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| 
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| __init void plat_time_init(void)
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| {
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| 	unsigned int configPR;
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| 	unsigned int n;
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| 	unsigned int m;
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| 	unsigned int p;
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| 	unsigned int pow2p;
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| 
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| 	pnx8xxx_clockevent.cpumask = cpu_none_mask;
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| 	clockevents_register_device(&pnx8xxx_clockevent);
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| 	clocksource_register(&pnx_clocksource);
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| 
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| 	/* Timer 1 start */
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| 	configPR = read_c0_config7();
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| 	configPR &= ~0x00000008;
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| 	write_c0_config7(configPR);
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| 
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| 	/* Timer 2 start */
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| 	configPR = read_c0_config7();
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| 	configPR &= ~0x00000010;
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| 	write_c0_config7(configPR);
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| 
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| 	/* Timer 3 stop */
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| 	configPR = read_c0_config7();
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| 	configPR |= 0x00000020;
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| 	write_c0_config7(configPR);
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| 
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| 
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|         /* PLL0 sets MIPS clock (PLL1 <=> TM1, PLL6 <=> TM2, PLL5 <=> mem) */
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|         /* (but only if CLK_MIPS_CTL select value [bits 3:1] is 1:  FIXME) */
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| 
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|         n = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_N_MASK) >> 16;
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|         m = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_M_MASK) >> 8;
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|         p = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_P_MASK) >> 2;
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| 	pow2p = (1 << p);
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| 
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| 	db_assert(m != 0 && pow2p != 0);
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| 
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|         /*
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| 	 * Compute the frequency as in the PNX8550 User Manual 1.0, p.186
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| 	 * (a.k.a. 8-10).  Divide by HZ for a timer offset that results in
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| 	 * HZ timer interrupts per second.
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| 	 */
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| 	mips_hpt_frequency = 27UL * ((1000000UL * n)/(m * pow2p));
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| 	cpj = DIV_ROUND_CLOSEST(mips_hpt_frequency, HZ);
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| 	write_c0_count(0);
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| 	timer_ack();
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| 
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| 	/* Setup Timer 2 */
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| 	write_c0_count2(0);
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| 	write_c0_compare2(0xffffffff);
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| 
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| 	setup_irq(PNX8550_INT_TIMER1, &pnx8xxx_timer_irq);
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| 	setup_irq(PNX8550_INT_TIMER2, &monotonic_irqaction);
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| }
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