To allow for some generic io accessors introduce io.h and use this instead of asm/io.h throughout the tree. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
74 lines
2.1 KiB
C
74 lines
2.1 KiB
C
/*
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* (C) Copyright 2010 Juergen Beisert - Pengutronix <kernel@pengutronix.de>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (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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#include <common.h>
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#include <init.h>
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#include <clock.h>
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#include <notifier.h>
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#include <mach/imx-regs.h>
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#include <mach/clock.h>
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#include <io.h>
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#define TIMROTCTRL 0x00
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# define TIMROTCTRL_SFTRST
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# define TIMROTCTRL_CLKGATE
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# define TIMROTCTRL_DIVIDER(x) ((x & 0x3f) << 16)
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#define TIMCTRL1 0x60
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#define TIMCTRL1_SET 0x64
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#define TIMCTRL1_CLR 0x68
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#define TIMCTRL1_TOG 0x6c
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# define TIMCTRL_RELOAD (1 << 6)
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# define TIMCTRL_UPDATE (1 << 7)
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# define TIMCTRL_PRESCALE(x) ((x & 0x3) << 4)
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# define TIMCTRL_SELECT(x) (x & 0xf)
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#define TIMCOUNT1 0x70
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#define TIMFIX1 0x80
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static const void __iomem * timer_base = (void *)IMX_TIM1_BASE;
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/* we are using the 32 kHz reference */
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#define CLOCK_TICK_RATE 32000
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static uint64_t imx28_clocksource_read(void)
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{
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return ~(readl(timer_base + TIMCOUNT1));
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}
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static struct clocksource imx28_cs = {
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.read = imx28_clocksource_read,
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.mask = CLOCKSOURCE_MASK(32),
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.shift = 17,
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};
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static int imx28_clocksource_init(void)
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{
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/* enable the whole timer block */
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writel(0x00000000, timer_base + TIMROTCTRL);
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/* setup start value of the general purpose timer */
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writel(0x00000000, timer_base + TIMCTRL1);
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writel(TIMCTRL_UPDATE, timer_base + TIMCTRL1);
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/* setup the reload value of the general purpose timer */
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writel(0xffffffff, timer_base + TIMFIX1);
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writel(TIMCTRL_UPDATE | TIMCTRL_RELOAD | TIMCTRL_PRESCALE(0) |
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TIMCTRL_SELECT(0xb), timer_base + TIMCTRL1);
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imx28_cs.mult = clocksource_hz2mult(CLOCK_TICK_RATE, imx28_cs.shift);
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init_clock(&imx28_cs);
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return 0;
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}
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core_initcall(imx28_clocksource_init);
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