diff options
Diffstat (limited to 'kernel/arch/arm/mach-s3c24xx/bast-irq.c')
| -rw-r--r-- | kernel/arch/arm/mach-s3c24xx/bast-irq.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-s3c24xx/bast-irq.c b/kernel/arch/arm/mach-s3c24xx/bast-irq.c new file mode 100644 index 000000000..cb1b79195 --- /dev/null +++ b/kernel/arch/arm/mach-s3c24xx/bast-irq.c @@ -0,0 +1,157 @@ +/* linux/arch/arm/mach-s3c2410/bast-irq.c + * + * Copyright 2003-2005 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * http://www.simtec.co.uk/products/EB2410ITX/ + * + * 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 <linux/init.h> +#include <linux/module.h> +#include <linux/ioport.h> +#include <linux/device.h> +#include <linux/io.h> + +#include <asm/irq.h> +#include <asm/mach-types.h> +#include <asm/mach/irq.h> + +#include <mach/hardware.h> +#include <mach/regs-irq.h> + +#include "bast.h" + +#define irqdbf(x...) +#define irqdbf2(x...) + +/* handle PC104 ISA interrupts from the system CPLD */ + +/* table of ISA irq nos to the relevant mask... zero means + * the irq is not implemented +*/ +static unsigned char bast_pc104_irqmasks[] = { + 0, /* 0 */ + 0, /* 1 */ + 0, /* 2 */ + 1, /* 3 */ + 0, /* 4 */ + 2, /* 5 */ + 0, /* 6 */ + 4, /* 7 */ + 0, /* 8 */ + 0, /* 9 */ + 8, /* 10 */ + 0, /* 11 */ + 0, /* 12 */ + 0, /* 13 */ + 0, /* 14 */ + 0, /* 15 */ +}; + +static unsigned char bast_pc104_irqs[] = { 3, 5, 7, 10 }; + +static void +bast_pc104_mask(struct irq_data *data) +{ + unsigned long temp; + + temp = __raw_readb(BAST_VA_PC104_IRQMASK); + temp &= ~bast_pc104_irqmasks[data->irq]; + __raw_writeb(temp, BAST_VA_PC104_IRQMASK); +} + +static void +bast_pc104_maskack(struct irq_data *data) +{ + struct irq_desc *desc = irq_desc + BAST_IRQ_ISA; + + bast_pc104_mask(data); + desc->irq_data.chip->irq_ack(&desc->irq_data); +} + +static void +bast_pc104_unmask(struct irq_data *data) +{ + unsigned long temp; + + temp = __raw_readb(BAST_VA_PC104_IRQMASK); + temp |= bast_pc104_irqmasks[data->irq]; + __raw_writeb(temp, BAST_VA_PC104_IRQMASK); +} + +static struct irq_chip bast_pc104_chip = { + .irq_mask = bast_pc104_mask, + .irq_unmask = bast_pc104_unmask, + .irq_ack = bast_pc104_maskack +}; + +static void +bast_irq_pc104_demux(unsigned int irq, + struct irq_desc *desc) +{ + unsigned int stat; + unsigned int irqno; + int i; + + stat = __raw_readb(BAST_VA_PC104_IRQREQ) & 0xf; + + if (unlikely(stat == 0)) { + /* ack if we get an irq with nothing (ie, startup) */ + + desc = irq_desc + BAST_IRQ_ISA; + desc->irq_data.chip->irq_ack(&desc->irq_data); + } else { + /* handle the IRQ */ + + for (i = 0; stat != 0; i++, stat >>= 1) { + if (stat & 1) { + irqno = bast_pc104_irqs[i]; + generic_handle_irq(irqno); + } + } + } +} + +static __init int bast_irq_init(void) +{ + unsigned int i; + + if (machine_is_bast()) { + printk(KERN_INFO "BAST PC104 IRQ routing, Copyright 2005 Simtec Electronics\n"); + + /* zap all the IRQs */ + + __raw_writeb(0x0, BAST_VA_PC104_IRQMASK); + + irq_set_chained_handler(BAST_IRQ_ISA, bast_irq_pc104_demux); + + /* register our IRQs */ + + for (i = 0; i < 4; i++) { + unsigned int irqno = bast_pc104_irqs[i]; + + irq_set_chip_and_handler(irqno, &bast_pc104_chip, + handle_level_irq); + set_irq_flags(irqno, IRQF_VALID); + } + } + + return 0; +} + +arch_initcall(bast_irq_init); |