/* * linux/arch/arm/mach-footbridge/dc21285-timer.c * * Copyright (C) 1998 Russell King. * Copyright (C) 1998 Phil Blundell */ #include <linux/init.h> #include <linux/interrupt.h> #include <linux/irq.h> #include <asm/irq.h> #include <asm/hardware/dec21285.h> #include <asm/mach/time.h> #include "common.h" /* * Footbridge timer 1 support. */ static unsigned long timer1_latch; static unsigned long timer1_gettimeoffset (void) { unsigned long value = timer1_latch - *CSR_TIMER1_VALUE; return ((tick_nsec / 1000) * value) / timer1_latch; } static irqreturn_t timer1_interrupt(int irq, void *dev_id) { write_seqlock(&xtime_lock); *CSR_TIMER1_CLR = 0; timer_tick(); write_sequnlock(&xtime_lock); return IRQ_HANDLED; } static struct irqaction footbridge_timer_irq = { .name = "Timer1 timer tick", .handler = timer1_interrupt, .flags = IRQF_DISABLED | IRQF_TIMER, }; /* * Set up timer interrupt. */ static void __init footbridge_timer_init(void) { timer1_latch = (mem_fclk_21285 + 8 * HZ) / (16 * HZ); *CSR_TIMER1_CLR = 0; *CSR_TIMER1_LOAD = timer1_latch; *CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD | TIMER_CNTL_DIV16; setup_irq(IRQ_TIMER1, &footbridge_timer_irq); isa_rtc_init(); } struct sys_timer footbridge_timer = { .init = footbridge_timer_init, .offset = timer1_gettimeoffset, };