/* * linux/arch/arm/mach-footbridge/irq.c * * Copyright (C) 1996-2000 Russell King * * 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. * * Changelog: * 22-Aug-1998 RMK Restructured IRQ routines * 03-Sep-1998 PJB Merged CATS support * 20-Jan-1998 RMK Started merge of EBSA286, CATS and NetWinder * 26-Jan-1999 PJB Don't use IACK on CATS * 16-Mar-1999 RMK Added autodetect of ISA PICs */ #include <linux/ioport.h> #include <linux/interrupt.h> #include <linux/list.h> #include <linux/init.h> #include <asm/mach/irq.h> #include <asm/hardware.h> #include <asm/hardware/dec21285.h> #include <asm/irq.h> #include <asm/io.h> #include <asm/mach-types.h> static void isa_mask_pic_lo_irq(unsigned int irq) { unsigned int mask = 1 << (irq & 7); outb(inb(PIC_MASK_LO) | mask, PIC_MASK_LO); } static void isa_ack_pic_lo_irq(unsigned int irq) { unsigned int mask = 1 << (irq & 7); outb(inb(PIC_MASK_LO) | mask, PIC_MASK_LO); outb(0x20, PIC_LO); } static void isa_unmask_pic_lo_irq(unsigned int irq) { unsigned int mask = 1 << (irq & 7); outb(inb(PIC_MASK_LO) & ~mask, PIC_MASK_LO); } static struct irqchip isa_lo_chip = { .ack = isa_ack_pic_lo_irq, .mask = isa_mask_pic_lo_irq, .unmask = isa_unmask_pic_lo_irq, }; static void isa_mask_pic_hi_irq(unsigned int irq) { unsigned int mask = 1 << (irq & 7); outb(inb(PIC_MASK_HI) | mask, PIC_MASK_HI); } static void isa_ack_pic_hi_irq(unsigned int irq) { unsigned int mask = 1 << (irq & 7); outb(inb(PIC_MASK_HI) | mask, PIC_MASK_HI); outb(0x62, PIC_LO); outb(0x20, PIC_HI); } static void isa_unmask_pic_hi_irq(unsigned int irq) { unsigned int mask = 1 << (irq & 7); outb(inb(PIC_MASK_HI) & ~mask, PIC_MASK_HI); } static struct irqchip isa_hi_chip = { .ack = isa_ack_pic_hi_irq, .mask = isa_mask_pic_hi_irq, .unmask = isa_unmask_pic_hi_irq, }; static void isa_irq_handler(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs) { unsigned int isa_irq = *(unsigned char *)PCIIACK_BASE; if (isa_irq < _ISA_IRQ(0) || isa_irq >= _ISA_IRQ(16)) { do_bad_IRQ(isa_irq, desc, regs); return; } desc = irq_desc + isa_irq; desc_handle_irq(isa_irq, desc, regs); } static struct irqaction irq_cascade = { .handler = no_action, .name = "cascade", }; static struct resource pic1_resource = { "pic1", 0x20, 0x3f }; static struct resource pic2_resource = { "pic2", 0xa0, 0xbf }; void __init isa_init_irq(unsigned int host_irq) { unsigned int irq; /* * Setup, and then probe for an ISA PIC * If the PIC is not there, then we * ignore the PIC. */ outb(0x11, PIC_LO); outb(_ISA_IRQ(0), PIC_MASK_LO); /* IRQ number */ outb(0x04, PIC_MASK_LO); /* Slave on Ch2 */ outb(0x01, PIC_MASK_LO); /* x86 */ outb(0xf5, PIC_MASK_LO); /* pattern: 11110101 */ outb(0x11, PIC_HI); outb(_ISA_IRQ(8), PIC_MASK_HI); /* IRQ number */ outb(0x02, PIC_MASK_HI); /* Slave on Ch1 */ outb(0x01, PIC_MASK_HI); /* x86 */ outb(0xfa, PIC_MASK_HI); /* pattern: 11111010 */ outb(0x0b, PIC_LO); outb(0x0b, PIC_HI); if (inb(PIC_MASK_LO) == 0xf5 && inb(PIC_MASK_HI) == 0xfa) { outb(0xff, PIC_MASK_LO);/* mask all IRQs */ outb(0xff, PIC_MASK_HI);/* mask all IRQs */ } else { printk(KERN_INFO "IRQ: ISA PIC not found\n"); host_irq = (unsigned int)-1; } if (host_irq != (unsigned int)-1) { for (irq = _ISA_IRQ(0); irq < _ISA_IRQ(8); irq++) { set_irq_chip(irq, &isa_lo_chip); set_irq_handler(irq, do_level_IRQ); set_irq_flags(irq, IRQF_VALID | IRQF_PROBE); } for (irq = _ISA_IRQ(8); irq < _ISA_IRQ(16); irq++) { set_irq_chip(irq, &isa_hi_chip); set_irq_handler(irq, do_level_IRQ); set_irq_flags(irq, IRQF_VALID | IRQF_PROBE); } request_resource(&ioport_resource, &pic1_resource); request_resource(&ioport_resource, &pic2_resource); setup_irq(IRQ_ISA_CASCADE, &irq_cascade); set_irq_chained_handler(host_irq, isa_irq_handler); /* * On the NetWinder, don't automatically * enable ISA IRQ11 when it is requested. * There appears to be a missing pull-up * resistor on this line. */ if (machine_is_netwinder()) set_irq_flags(_ISA_IRQ(11), IRQF_VALID | IRQF_PROBE | IRQF_NOAUTOEN); } }