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Diffstat (limited to 'arch/arm/cpu/ixp/timer.c')
| -rw-r--r-- | arch/arm/cpu/ixp/timer.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/arch/arm/cpu/ixp/timer.c b/arch/arm/cpu/ixp/timer.c new file mode 100644 index 0000000..edf341f --- /dev/null +++ b/arch/arm/cpu/ixp/timer.c @@ -0,0 +1,135 @@ +/* + * (C) Copyright 2006 + * Stefan Roese, DENX Software Engineering, sr@denx.de. + * + * (C) Copyright 2002 + * Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Marius Groeger <mgroeger@sysgo.de> + * + * (C) Copyright 2002 + * Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Alex Zuepke <azu@sysgo.de> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <asm/arch/ixp425.h> + +#ifdef CONFIG_TIMER_IRQ + +#define FREQ 66666666 +#define CLOCK_TICK_RATE (((FREQ / CONFIG_SYS_HZ & ~IXP425_OST_RELOAD_MASK) + 1) * CONFIG_SYS_HZ) +#define LATCH ((CLOCK_TICK_RATE + CONFIG_SYS_HZ/2) / CONFIG_SYS_HZ) /* For divider */ + +/* + * When interrupts are enabled, use timer 2 for time/delay generation... + */ + +static volatile ulong timestamp; + +static void timer_isr(void *data) +{ + unsigned int *pTime = (unsigned int *)data; + + (*pTime)++; + + /* + * Reset IRQ source + */ + *IXP425_OSST = IXP425_OSST_TIMER_2_PEND; +} + +ulong get_timer (ulong base) +{ + return timestamp - base; +} + +void reset_timer (void) +{ + timestamp = 0; +} + +int timer_init (void) +{ + /* install interrupt handler for timer */ + irq_install_handler(IXP425_TIMER_2_IRQ, timer_isr, (void *)×tamp); + + /* setup the Timer counter value */ + *IXP425_OSRT2 = (LATCH & ~IXP425_OST_RELOAD_MASK) | IXP425_OST_ENABLE; + + /* enable timer irq */ + *IXP425_ICMR = (1 << IXP425_TIMER_2_IRQ); + + return 0; +} +#else +ulong get_timer (ulong base) +{ + return get_timer_masked () - base; +} + +void ixp425_udelay(unsigned long usec) +{ + /* + * This function has a max usec, but since it is called from udelay + * we should not have to worry... be happy + */ + unsigned long usecs = CONFIG_SYS_HZ/1000000L & ~IXP425_OST_RELOAD_MASK; + + *IXP425_OSST = IXP425_OSST_TIMER_1_PEND; + usecs |= IXP425_OST_ONE_SHOT | IXP425_OST_ENABLE; + *IXP425_OSRT1 = usecs; + while (!(*IXP425_OSST & IXP425_OSST_TIMER_1_PEND)); +} + +void __udelay (unsigned long usec) +{ + while (usec--) ixp425_udelay(1); +} + +static ulong reload_constant = 0xfffffff0; + +void reset_timer_masked (void) +{ + ulong reload = reload_constant | IXP425_OST_ONE_SHOT | IXP425_OST_ENABLE; + + *IXP425_OSST = IXP425_OSST_TIMER_1_PEND; + *IXP425_OSRT1 = reload; +} + +ulong get_timer_masked (void) +{ + /* + * Note that it is possible for this to wrap! + * In this case we return max. + */ + ulong current = *IXP425_OST1; + if (*IXP425_OSST & IXP425_OSST_TIMER_1_PEND) + { + return reload_constant; + } + return (reload_constant - current); +} + +int timer_init(void) +{ + return 0; +} +#endif |