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/*
* linux/arch/arm/mach-aaec2000/core.c
*
* Code common to all AAEC-2000 machines
*
* Copyright (c) 2005 Nicolas Bellido Y Ortega
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/timex.h>
#include <linux/signal.h>
#include <asm/hardware.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include <asm/mach/time.h>
#include <asm/mach/map.h>
/*
* Common I/O mapping:
*
* Static virtual address mappings are as follow:
*
* 0xf8000000-0xf8001ffff: Devices connected to APB bus
* 0xf8002000-0xf8003ffff: Devices connected to AHB bus
*
* Below 0xe8000000 is reserved for vm allocation.
*
* The machine specific code must provide the extra mapping beside the
* default mapping provided here.
*/
static struct map_desc standard_io_desc[] __initdata = {
/* virtual physical length type */
{ VIO_APB_BASE, PIO_APB_BASE, IO_APB_LENGTH, MT_DEVICE },
{ VIO_AHB_BASE, PIO_AHB_BASE, IO_AHB_LENGTH, MT_DEVICE }
};
void __init aaec2000_map_io(void)
{
iotable_init(standard_io_desc, ARRAY_SIZE(standard_io_desc));
}
/*
* Interrupt handling routines
*/
static void aaec2000_int_ack(unsigned int irq)
{
IRQ_INTSR = 1 << irq;
}
static void aaec2000_int_mask(unsigned int irq)
{
IRQ_INTENC |= (1 << irq);
}
static void aaec2000_int_unmask(unsigned int irq)
{
IRQ_INTENS |= (1 << irq);
}
static struct irqchip aaec2000_irq_chip = {
.ack = aaec2000_int_ack,
.mask = aaec2000_int_mask,
.unmask = aaec2000_int_unmask,
};
void __init aaec2000_init_irq(void)
{
unsigned int i;
for (i = 0; i < NR_IRQS; i++) {
set_irq_handler(i, do_level_IRQ);
set_irq_chip(i, &aaec2000_irq_chip);
set_irq_flags(i, IRQF_VALID);
}
/* Disable all interrupts */
IRQ_INTENC = 0xffffffff;
/* Clear any pending interrupts */
IRQ_INTSR = IRQ_INTSR;
}
/*
* Time keeping
*/
/* IRQs are disabled before entering here from do_gettimeofday() */
static unsigned long aaec2000_gettimeoffset(void)
{
unsigned long ticks_to_match, elapsed, usec;
/* Get ticks before next timer match */
ticks_to_match = TIMER1_LOAD - TIMER1_VAL;
/* We need elapsed ticks since last match */
elapsed = LATCH - ticks_to_match;
/* Now, convert them to usec */
usec = (unsigned long)(elapsed * (tick_nsec / 1000))/LATCH;
return usec;
}
/* We enter here with IRQs enabled */
static irqreturn_t
aaec2000_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
/* TODO: Check timer accuracy */
write_seqlock(&xtime_lock);
timer_tick(regs);
TIMER1_CLEAR = 1;
write_sequnlock(&xtime_lock);
return IRQ_HANDLED;
}
static struct irqaction aaec2000_timer_irq = {
.name = "AAEC-2000 Timer Tick",
.flags = SA_INTERRUPT,
.handler = aaec2000_timer_interrupt
};
static void __init aaec2000_timer_init(void)
{
/* Disable timer 1 */
TIMER1_CTRL = 0;
/* We have somehow to generate a 100Hz clock.
* We then use the 508KHz timer in periodic mode.
*/
TIMER1_LOAD = LATCH;
TIMER1_CLEAR = 1; /* Clear interrupt */
setup_irq(INT_TMR1_OFL, &aaec2000_timer_irq);
TIMER1_CTRL = TIMER_CTRL_ENABLE |
TIMER_CTRL_PERIODIC |
TIMER_CTRL_CLKSEL_508K;
}
struct sys_timer aaec2000_timer = {
.init = aaec2000_timer_init,
.offset = aaec2000_gettimeoffset,
};
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