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Diffstat (limited to 'arch/arm/mach-aaec2000/core.c')
-rw-r--r-- | arch/arm/mach-aaec2000/core.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/arch/arm/mach-aaec2000/core.c b/arch/arm/mach-aaec2000/core.c new file mode 100644 index 00000000000..aece0cd4f0a --- /dev/null +++ b/arch/arm/mach-aaec2000/core.c @@ -0,0 +1,157 @@ +/* + * 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 | SA_TIMER, + .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, +}; + |