1/* arch/arm/plat-samsung/irq-vic-timer.c 2 * originally part of arch/arm/plat-s3c64xx/irq.c 3 * 4 * Copyright 2008 Openmoko, Inc. 5 * Copyright 2008 Simtec Electronics 6 * Ben Dooks <ben@simtec.co.uk> 7 * http://armlinux.simtec.co.uk/ 8 * 9 * S3C64XX - Interrupt handling 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License version 2 as 13 * published by the Free Software Foundation. 14 */ 15 16#include <linux/kernel.h> 17#include <linux/interrupt.h> 18#include <linux/irq.h> 19#include <linux/io.h> 20 21#include <mach/map.h> 22#include <plat/irq-vic-timer.h> 23#include <plat/regs-timer.h> 24 25static void s3c_irq_demux_vic_timer(unsigned int irq, struct irq_desc *desc) 26{ 27 generic_handle_irq((int)desc->handler_data); 28} 29 30/* We assume the IRQ_TIMER0..IRQ_TIMER4 range is continuous. */ 31 32static void s3c_irq_timer_mask(unsigned int irq) 33{ 34 u32 reg = __raw_readl(S3C64XX_TINT_CSTAT); 35 36 reg &= 0x1f; /* mask out pending interrupts */ 37 reg &= ~(1 << (irq - IRQ_TIMER0)); 38 __raw_writel(reg, S3C64XX_TINT_CSTAT); 39} 40 41static void s3c_irq_timer_unmask(unsigned int irq) 42{ 43 u32 reg = __raw_readl(S3C64XX_TINT_CSTAT); 44 45 reg &= 0x1f; /* mask out pending interrupts */ 46 reg |= 1 << (irq - IRQ_TIMER0); 47 __raw_writel(reg, S3C64XX_TINT_CSTAT); 48} 49 50static void s3c_irq_timer_ack(unsigned int irq) 51{ 52 u32 reg = __raw_readl(S3C64XX_TINT_CSTAT); 53 54 reg &= 0x1f; 55 reg |= (1 << 5) << (irq - IRQ_TIMER0); 56 __raw_writel(reg, S3C64XX_TINT_CSTAT); 57} 58 59static struct irq_chip s3c_irq_timer = { 60 .name = "s3c-timer", 61 .mask = s3c_irq_timer_mask, 62 .unmask = s3c_irq_timer_unmask, 63 .ack = s3c_irq_timer_ack, 64}; 65 66/** 67 * s3c_init_vic_timer_irq() - initialise timer irq chanined off VIC.\ 68 * @parent_irq: The parent IRQ on the VIC for the timer. 69 * @timer_irq: The IRQ to be used for the timer. 70 * 71 * Register the necessary IRQ chaining and support for the timer IRQs 72 * chained of the VIC. 73 */ 74void __init s3c_init_vic_timer_irq(unsigned int parent_irq, 75 unsigned int timer_irq) 76{ 77 struct irq_desc *desc = irq_to_desc(parent_irq); 78 79 set_irq_chained_handler(parent_irq, s3c_irq_demux_vic_timer); 80 81 set_irq_chip(timer_irq, &s3c_irq_timer); 82 set_irq_handler(timer_irq, handle_level_irq); 83 set_irq_flags(timer_irq, IRQF_VALID); 84 85 desc->handler_data = (void *)timer_irq; 86} 87