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c5d710654c
In preparation for making the clockevents core NTP correction aware, all clockevent device drivers must set ->min_delta_ticks and ->max_delta_ticks rather than ->min_delta_ns and ->max_delta_ns: a clockevent device's rate is going to change dynamically and thus, the ratio of ns to ticks ceases to stay invariant. Make the score arch's clockevent driver initialize these fields properly. This patch alone doesn't introduce any change in functionality as the clockevents core still looks exclusively at the (untouched) ->min_delta_ns and ->max_delta_ns. As soon as this has changed, a followup patch will purge the initialization of ->min_delta_ns and ->max_delta_ns from this driver. Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Lennox Wu <lennox.wu@gmail.com> Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
90 lines
2.6 KiB
C
90 lines
2.6 KiB
C
/*
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* arch/score/kernel/time.c
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*
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* Score Processor version.
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*
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* Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
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* Chen Liqin <liqin.chen@sunplusct.com>
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* Lennox Wu <lennox.wu@sunplusct.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see the file COPYING, or write
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* to the Free Software Foundation, Inc.,
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* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <linux/clockchips.h>
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#include <linux/interrupt.h>
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#include <asm/scoreregs.h>
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static irqreturn_t timer_interrupt(int irq, void *dev_id)
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{
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struct clock_event_device *evdev = dev_id;
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/* clear timer interrupt flag */
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outl(1, P_TIMER0_CPP_REG);
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evdev->event_handler(evdev);
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return IRQ_HANDLED;
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}
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static struct irqaction timer_irq = {
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.handler = timer_interrupt,
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.flags = IRQF_TIMER,
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.name = "timer",
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};
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static int score_timer_set_next_event(unsigned long delta,
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struct clock_event_device *evdev)
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{
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outl((TMR_M_PERIODIC | TMR_IE_ENABLE), P_TIMER0_CTRL);
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outl(delta, P_TIMER0_PRELOAD);
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outl(inl(P_TIMER0_CTRL) | TMR_ENABLE, P_TIMER0_CTRL);
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return 0;
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}
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static int score_timer_set_periodic(struct clock_event_device *evt)
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{
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outl((TMR_M_PERIODIC | TMR_IE_ENABLE), P_TIMER0_CTRL);
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outl(SYSTEM_CLOCK / HZ, P_TIMER0_PRELOAD);
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outl(inl(P_TIMER0_CTRL) | TMR_ENABLE, P_TIMER0_CTRL);
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return 0;
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}
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static struct clock_event_device score_clockevent = {
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.name = "score_clockevent",
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.features = CLOCK_EVT_FEAT_PERIODIC,
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.shift = 16,
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.set_next_event = score_timer_set_next_event,
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.set_state_periodic = score_timer_set_periodic,
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};
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void __init time_init(void)
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{
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timer_irq.dev_id = &score_clockevent;
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setup_irq(IRQ_TIMER , &timer_irq);
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/* setup COMPARE clockevent */
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score_clockevent.mult = div_sc(SYSTEM_CLOCK, NSEC_PER_SEC,
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score_clockevent.shift);
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score_clockevent.max_delta_ns = clockevent_delta2ns((u32)~0,
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&score_clockevent);
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score_clockevent.max_delta_ticks = (u32)~0;
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score_clockevent.min_delta_ns = clockevent_delta2ns(50,
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&score_clockevent) + 1;
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score_clockevent.min_delta_ticks = 50;
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score_clockevent.cpumask = cpumask_of(0);
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clockevents_register_device(&score_clockevent);
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}
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