44377f622e
The defines and typedefs (hw_interrupt_type, no_irq_type, irq_desc_t) have been kept around for migration reasons. After more than two years it's time to remove them finally. This patch cleans up one of the remaining users. When all such patches hit mainline we can remove the defines and typedefs finally. Impact: cleanup Convert the last remaining users to struct irq_chip and remove the define. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
183 lines
4.2 KiB
C
183 lines
4.2 KiB
C
/*
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* linux/arch/alpha/kernel/irq_i8259.c
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*
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* This is the 'legacy' 8259A Programmable Interrupt Controller,
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* present in the majority of PC/AT boxes.
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*
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* Started hacking from linux-2.3.30pre6/arch/i386/kernel/i8259.c.
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*/
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#include <linux/init.h>
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#include <linux/cache.h>
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#include <linux/sched.h>
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#include <linux/irq.h>
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#include <linux/interrupt.h>
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#include <asm/io.h>
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#include "proto.h"
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#include "irq_impl.h"
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/* Note mask bit is true for DISABLED irqs. */
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static unsigned int cached_irq_mask = 0xffff;
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static DEFINE_SPINLOCK(i8259_irq_lock);
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static inline void
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i8259_update_irq_hw(unsigned int irq, unsigned long mask)
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{
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int port = 0x21;
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if (irq & 8) mask >>= 8;
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if (irq & 8) port = 0xA1;
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outb(mask, port);
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}
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inline void
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i8259a_enable_irq(unsigned int irq)
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{
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spin_lock(&i8259_irq_lock);
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i8259_update_irq_hw(irq, cached_irq_mask &= ~(1 << irq));
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spin_unlock(&i8259_irq_lock);
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}
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static inline void
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__i8259a_disable_irq(unsigned int irq)
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{
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i8259_update_irq_hw(irq, cached_irq_mask |= 1 << irq);
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}
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void
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i8259a_disable_irq(unsigned int irq)
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{
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spin_lock(&i8259_irq_lock);
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__i8259a_disable_irq(irq);
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spin_unlock(&i8259_irq_lock);
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}
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void
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i8259a_mask_and_ack_irq(unsigned int irq)
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{
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spin_lock(&i8259_irq_lock);
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__i8259a_disable_irq(irq);
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/* Ack the interrupt making it the lowest priority. */
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if (irq >= 8) {
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outb(0xE0 | (irq - 8), 0xa0); /* ack the slave */
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irq = 2;
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}
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outb(0xE0 | irq, 0x20); /* ack the master */
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spin_unlock(&i8259_irq_lock);
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}
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unsigned int
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i8259a_startup_irq(unsigned int irq)
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{
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i8259a_enable_irq(irq);
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return 0; /* never anything pending */
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}
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void
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i8259a_end_irq(unsigned int irq)
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{
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if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
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i8259a_enable_irq(irq);
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}
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struct irq_chip i8259a_irq_type = {
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.typename = "XT-PIC",
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.startup = i8259a_startup_irq,
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.shutdown = i8259a_disable_irq,
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.enable = i8259a_enable_irq,
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.disable = i8259a_disable_irq,
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.ack = i8259a_mask_and_ack_irq,
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.end = i8259a_end_irq,
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};
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void __init
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init_i8259a_irqs(void)
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{
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static struct irqaction cascade = {
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.handler = no_action,
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.name = "cascade",
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};
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long i;
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outb(0xff, 0x21); /* mask all of 8259A-1 */
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outb(0xff, 0xA1); /* mask all of 8259A-2 */
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for (i = 0; i < 16; i++) {
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irq_desc[i].status = IRQ_DISABLED;
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irq_desc[i].chip = &i8259a_irq_type;
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}
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setup_irq(2, &cascade);
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}
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#if defined(CONFIG_ALPHA_GENERIC)
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# define IACK_SC alpha_mv.iack_sc
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#elif defined(CONFIG_ALPHA_APECS)
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# define IACK_SC APECS_IACK_SC
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#elif defined(CONFIG_ALPHA_LCA)
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# define IACK_SC LCA_IACK_SC
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#elif defined(CONFIG_ALPHA_CIA)
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# define IACK_SC CIA_IACK_SC
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#elif defined(CONFIG_ALPHA_PYXIS)
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# define IACK_SC PYXIS_IACK_SC
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#elif defined(CONFIG_ALPHA_TITAN)
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# define IACK_SC TITAN_IACK_SC
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#elif defined(CONFIG_ALPHA_TSUNAMI)
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# define IACK_SC TSUNAMI_IACK_SC
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#elif defined(CONFIG_ALPHA_IRONGATE)
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# define IACK_SC IRONGATE_IACK_SC
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#endif
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/* Note that CONFIG_ALPHA_POLARIS is intentionally left out here, since
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sys_rx164 wants to use isa_no_iack_sc_device_interrupt for some reason. */
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#if defined(IACK_SC)
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void
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isa_device_interrupt(unsigned long vector)
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{
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/*
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* Generate a PCI interrupt acknowledge cycle. The PIC will
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* respond with the interrupt vector of the highest priority
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* interrupt that is pending. The PALcode sets up the
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* interrupts vectors such that irq level L generates vector L.
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*/
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int j = *(vuip) IACK_SC;
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j &= 0xff;
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handle_irq(j);
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}
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#endif
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#if defined(CONFIG_ALPHA_GENERIC) || !defined(IACK_SC)
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void
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isa_no_iack_sc_device_interrupt(unsigned long vector)
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{
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unsigned long pic;
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/*
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* It seems to me that the probability of two or more *device*
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* interrupts occurring at almost exactly the same time is
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* pretty low. So why pay the price of checking for
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* additional interrupts here if the common case can be
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* handled so much easier?
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*/
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/*
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* The first read of gives you *all* interrupting lines.
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* Therefore, read the mask register and and out those lines
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* not enabled. Note that some documentation has 21 and a1
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* write only. This is not true.
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*/
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pic = inb(0x20) | (inb(0xA0) << 8); /* read isr */
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pic &= 0xFFFB; /* mask out cascade & hibits */
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while (pic) {
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int j = ffz(~pic);
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pic &= pic - 1;
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handle_irq(j);
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}
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}
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#endif
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