89 lines
2.3 KiB
C
89 lines
2.3 KiB
C
/*
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* arch/arm/mach-netx/time.c
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*
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* Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
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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 version 2
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* as published by the Free Software Foundation.
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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, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <asm/hardware.h>
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#include <asm/io.h>
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#include <asm/mach/time.h>
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#include <asm/arch/netx-regs.h>
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/*
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* Returns number of us since last clock interrupt. Note that interrupts
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* will have been disabled by do_gettimeoffset()
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*/
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static unsigned long netx_gettimeoffset(void)
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{
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return readl(NETX_GPIO_COUNTER_CURRENT(0)) / 100;
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}
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/*
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* IRQ handler for the timer
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*/
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static irqreturn_t
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netx_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
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{
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write_seqlock(&xtime_lock);
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timer_tick(regs);
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write_sequnlock(&xtime_lock);
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/* acknowledge interrupt */
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writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
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return IRQ_HANDLED;
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}
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static struct irqaction netx_timer_irq = {
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.name = "NetX Timer Tick",
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.flags = SA_INTERRUPT | SA_TIMER,
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.handler = netx_timer_interrupt,
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};
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/*
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* Set up timer interrupt
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*/
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static void __init netx_timer_init(void)
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{
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/* disable timer initially */
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writel(0, NETX_GPIO_COUNTER_CTRL(0));
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/* Reset the timer value to zero */
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writel(0, NETX_GPIO_COUNTER_CURRENT(0));
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writel(LATCH, NETX_GPIO_COUNTER_MAX(0));
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/* acknowledge interrupt */
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writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
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/* Enable the interrupt in the specific timer register and start timer */
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writel(COUNTER_BIT(0), NETX_GPIO_IRQ_ENABLE);
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writel(NETX_GPIO_COUNTER_CTRL_IRQ_EN | NETX_GPIO_COUNTER_CTRL_RUN,
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NETX_GPIO_COUNTER_CTRL(0));
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setup_irq(NETX_IRQ_TIMER0, &netx_timer_irq);
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}
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struct sys_timer netx_timer = {
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.init = netx_timer_init,
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.offset = netx_gettimeoffset,
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};
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