/* * include/asm-mips/i8259.h * * i8259A interrupt definitions. * * Copyright (C) 2003 Maciej W. Rozycki * Copyright (C) 2003 Ralf Baechle <ralf@linux-mips.org> * * 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. */ #ifndef _ASM_I8259_H #define _ASM_I8259_H #include <linux/compiler.h> #include <linux/spinlock.h> #include <asm/io.h> #include <irq.h> /* i8259A PIC registers */ #define PIC_MASTER_CMD 0x20 #define PIC_MASTER_IMR 0x21 #define PIC_MASTER_ISR PIC_MASTER_CMD #define PIC_MASTER_POLL PIC_MASTER_ISR #define PIC_MASTER_OCW3 PIC_MASTER_ISR #define PIC_SLAVE_CMD 0xa0 #define PIC_SLAVE_IMR 0xa1 /* i8259A PIC related value */ #define PIC_CASCADE_IR 2 #define MASTER_ICW4_DEFAULT 0x01 #define SLAVE_ICW4_DEFAULT 0x01 #define PIC_ICW4_AEOI 2 extern raw_spinlock_t i8259A_lock; extern void make_8259A_irq(unsigned int irq); extern void init_i8259_irqs(void); extern int i8259_of_init(struct device_node *node, struct device_node *parent); /** * i8159_set_poll() - Override the i8259 polling function * @poll: pointer to platform-specific polling function * * Call this to override the generic i8259 polling function, which directly * accesses i8259 registers, with a platform specific one which may be faster * in cases where hardware provides a more optimal means of polling for an * interrupt. */ extern void i8259_set_poll(int (*poll)(void)); /* * Do the traditional i8259 interrupt polling thing. This is for the few * cases where no better interrupt acknowledge method is available and we * absolutely must touch the i8259. */
static inline int i8259_irq(void) { int irq; raw_spin_lock(&i8259A_lock); /* Perform an interrupt acknowledge cycle on controller 1. */ outb(0x0C, PIC_MASTER_CMD); /* prepare for poll */ irq = inb(PIC_MASTER_CMD) & 7; if (irq == PIC_CASCADE_IR) { /* * Interrupt is cascaded so perform interrupt * acknowledge on controller 2. */ outb(0x0C, PIC_SLAVE_CMD); /* prepare for poll */ irq = (inb(PIC_SLAVE_CMD) & 7) + 8; } if (unlikely(irq == 7)) { /* * This may be a spurious interrupt. * * Read the interrupt status register (ISR). If the most * significant bit is not set then there is no valid * interrupt. */ outb(0x0B, PIC_MASTER_ISR); /* ISR register */ if(~inb(PIC_MASTER_ISR) & 0x80) irq = -1; } raw_spin_unlock(&i8259A_lock); return likely(irq >= 0) ? irq + I8259A_IRQ_BASE : irq; }Contributors
| Person | Tokens | Prop | Commits | CommitProp | |
| andrew morton | andrew morton | 101 | 83.47% | 1 | 33.33% |
| atsushi nemoto | atsushi nemoto | 18 | 14.88% | 1 | 33.33% |
| ralf baechle | ralf baechle | 2 | 1.65% | 1 | 33.33% |
| Total | 121 | 100.00% | 3 | 100.00% |
| Person | Tokens | Prop | Commits | CommitProp | |
| andrew morton | andrew morton | 109 | 45.42% | 1 | 11.11% |
| atsushi nemoto | atsushi nemoto | 76 | 31.67% | 2 | 22.22% |
| paul burton | paul burton | 30 | 12.50% | 2 | 22.22% |
| ralf baechle | ralf baechle | 24 | 10.00% | 3 | 33.33% |
| yoichi yuasa | yoichi yuasa | 1 | 0.42% | 1 | 11.11% |
| Total | 240 | 100.00% | 9 | 100.00% |