From: Thomas Gleixner <[email protected]>
enable platforms to use the irq-chip and irq-flow abstractions:
allow setting of the chip, the type and provide highlevel handlers
for common irq-flows.
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
include/linux/irq.h | 14 +
kernel/irq/Makefile | 2
kernel/irq/chip.c | 370 ++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 385 insertions(+), 1 deletion(-)
Index: linux-genirq.q/include/linux/irq.h
===================================================================
--- linux-genirq.q.orig/include/linux/irq.h
+++ linux-genirq.q/include/linux/irq.h
@@ -308,6 +308,20 @@ extern int can_request_irq(unsigned int
/* Dummy irq-chip implementation: */
extern struct irq_chip no_irq_chip;
+/* Set/get chip/data for an IRQ: */
+
+extern int set_irq_chip(unsigned int irq, struct irq_chip *chip);
+extern int set_irq_data(unsigned int irq, void *data);
+extern int set_irq_chip_data(unsigned int irq, void *data);
+extern int set_irq_type(unsigned int irq, unsigned int type);
+
+#define get_irq_chip(irq) (irq_desc[irq].handler)
+#define get_irq_chip_data(irq) (irq_desc[irq].chip_data)
+#define get_irq_data(irq) (irq_desc[irq].handler_data)
+
+/* Set default functions for irq_chip structures: */
+extern void irq_chip_set_defaults(struct irq_chip *chip);
+
#endif /* CONFIG_GENERIC_HARDIRQS */
#endif /* !CONFIG_S390 */
Index: linux-genirq.q/kernel/irq/Makefile
===================================================================
--- linux-genirq.q.orig/kernel/irq/Makefile
+++ linux-genirq.q/kernel/irq/Makefile
@@ -1,5 +1,5 @@
-obj-y := handle.o manage.o spurious.o resend.o
+obj-y := handle.o manage.o spurious.o resend.o chip.o
obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o
obj-$(CONFIG_PROC_FS) += proc.o
obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
Index: linux-genirq.q/kernel/irq/chip.c
===================================================================
--- /dev/null
+++ linux-genirq.q/kernel/irq/chip.c
@@ -0,0 +1,370 @@
+/*
+ * linux/kernel/irq/chip.c
+ *
+ * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
+ * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
+ *
+ * This file contains the core interrupt handling code, for irq-chip
+ * based architectures.
+ *
+ * Detailed information is available in Documentation/DocBook/genericirq
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+
+#include "internals.h"
+
+/**
+ * set_irq_chip - set the irq chip for an irq
+ * @irq: irq number
+ * @chip: pointer to irq chip description structure
+ */
+int set_irq_chip(unsigned int irq, struct irq_chip *chip)
+{
+ struct irq_desc *desc;
+ unsigned long flags;
+
+ if (irq >= NR_IRQS) {
+ printk(KERN_ERR "Trying to install chip for IRQ%d\n", irq);
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ if (!chip)
+ chip = &no_irq_chip;
+
+ desc = irq_desc + irq;
+ spin_lock_irqsave(&desc->lock, flags);
+ irq_chip_set_defaults(chip);
+ desc->handler = chip;
+ spin_unlock_irqrestore(&desc->lock, flags);
+ return 0;
+}
+EXPORT_SYMBOL(set_irq_chip);
+
+/**
+ * set_irq_type - set the irq type for an irq
+ * @irq: irq number
+ * @type: interrupt type - see include/linux/interrupt.h
+ */
+int set_irq_type(unsigned int irq, unsigned int type)
+{
+ struct irq_desc *desc;
+ unsigned long flags;
+ int ret = -ENXIO;
+
+ if (irq >= NR_IRQS) {
+ printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
+ return -ENODEV;
+ }
+
+ desc = irq_desc + irq;
+ if (desc->handler->set_type) {
+ spin_lock_irqsave(&desc->lock, flags);
+ ret = desc->handler->set_type(irq, type);
+ spin_unlock_irqrestore(&desc->lock, flags);
+ }
+ return ret;
+}
+EXPORT_SYMBOL(set_irq_type);
+
+/**
+ * set_irq_data - set irq type data for an irq
+ * @irq: Interrupt number
+ * @data: Pointer to interrupt specific data
+ *
+ * Set the hardware irq controller data for an irq
+ */
+int set_irq_data(unsigned int irq, void *data)
+{
+ struct irq_desc *desc;
+ unsigned long flags;
+
+ if (irq >= NR_IRQS) {
+ printk(KERN_ERR
+ "Trying to install controller data for IRQ%d\n", irq);
+ return -EINVAL;
+ }
+
+ desc = irq_desc + irq;
+ spin_lock_irqsave(&desc->lock, flags);
+ desc->handler_data = data;
+ spin_unlock_irqrestore(&desc->lock, flags);
+ return 0;
+}
+EXPORT_SYMBOL(set_irq_data);
+
+/**
+ * set_irq_chip_data - set irq chip data for an irq
+ * @irq: Interrupt number
+ * @data: Pointer to chip specific data
+ *
+ * Set the hardware irq chip data for an irq
+ */
+int set_irq_chip_data(unsigned int irq, void *data)
+{
+ struct irq_desc *desc = irq_desc + irq;
+ unsigned long flags;
+
+ if (irq >= NR_IRQS || !desc->handler) {
+ printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq);
+ return -EINVAL;
+ }
+
+ spin_lock_irqsave(&desc->lock, flags);
+ desc->chip_data = data;
+ spin_unlock_irqrestore(&desc->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(set_irq_chip_data);
+
+/*
+ * default enable function
+ */
+static void default_enable(unsigned int irq)
+{
+ struct irq_desc *desc = irq_desc + irq;
+
+ desc->handler->unmask(irq);
+ desc->status &= ~IRQ_MASKED;
+}
+
+/*
+ * default disable function
+ */
+static void default_disable(unsigned int irq)
+{
+ irq_desc[irq].handler->mask(irq);
+}
+
+/*
+ * default startup function
+ */
+static unsigned int default_startup(unsigned int irq)
+{
+ irq_desc[irq].handler->enable(irq);
+
+ return 0;
+}
+
+/*
+ * Fixup enable/disable function pointers
+ */
+void irq_chip_set_defaults(struct irq_chip *chip)
+{
+ if (!chip->enable)
+ chip->enable = default_enable;
+ if (!chip->disable)
+ chip->disable = default_disable;
+ if (!chip->startup)
+ chip->startup = default_startup;
+ if (!chip->shutdown)
+ chip->shutdown = chip->disable;
+}
+
+static inline void mask_ack_irq(struct irq_desc *desc, int irq)
+{
+ if (desc->handler->mask_ack)
+ desc->handler->mask_ack(irq);
+ else {
+ desc->handler->mask(irq);
+ desc->handler->ack(irq);
+ }
+}
+
+/**
+ * handle_simple_irq - Simple and software-decoded IRQs.
+ * @irq: the interrupt number
+ * @desc: the interrupt description structure for this irq
+ * @regs: pointer to a register structure
+ *
+ * Simple interrupts are either sent from a demultiplexing interrupt
+ * handler or come from hardware, where no interrupt hardware control
+ * is necessary.
+ *
+ * Note: The caller is expected to handle the ack, clear, mask and
+ * unmask issues if necessary.
+ *
+ * Must be called with the irq_desc->lock held
+ */
+void
+handle_simple_irq(unsigned int irq, struct irq_desc *desc, struct pt_regs *regs)
+{
+ struct irqaction *action;
+ irqreturn_t action_ret;
+ const unsigned int cpu = smp_processor_id();
+
+ kstat_cpu(cpu).irqs[irq]++;
+
+ desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
+
+ action = desc->action;
+ if (unlikely(!action || desc->depth))
+ return;
+
+ desc->status |= IRQ_INPROGRESS;
+ spin_unlock(&desc->lock);
+ action_ret = handle_IRQ_event(irq, regs, action);
+ if (!noirqdebug)
+ note_interrupt(irq, desc, action_ret, regs);
+ spin_lock(&desc->lock);
+ desc->status &= ~IRQ_INPROGRESS;
+}
+
+/**
+ * handle_level_irq - Level type irq handler
+ * @irq: the interrupt number
+ * @desc: the interrupt description structure for this irq
+ * @regs: pointer to a register structure
+ *
+ * Level type interrupts are active as long as the hardware line has
+ * the active level. This may require to mask the interrupt and unmask it
+ * after the associated handler has acknowledged the device, so the
+ * interrupt line is back to inactive.
+ *
+ * Must be called with the irq_desc->lock held
+ */
+void
+handle_level_irq(unsigned int irq, struct irq_desc *desc, struct pt_regs *regs)
+{
+ struct irqaction *action;
+ irqreturn_t action_ret;
+ const unsigned int cpu = smp_processor_id();
+
+ kstat_cpu(cpu).irqs[irq]++;
+
+ desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
+
+ mask_ack_irq(desc, irq);
+
+ /*
+ * If its disabled or no action available
+ * keep it masked and get out of here
+ */
+ action = desc->action;
+ if (unlikely(!action || desc->depth))
+ goto out;
+
+ desc->status |= IRQ_INPROGRESS;
+ spin_unlock(&desc->lock);
+ action_ret = handle_IRQ_event(irq, regs, action);
+ if (!noirqdebug)
+ note_interrupt(irq, desc, action_ret, regs);
+ spin_lock(&desc->lock);
+
+ desc->status &= ~IRQ_INPROGRESS;
+out:
+ if (!desc->depth && desc->handler->unmask)
+ desc->handler->unmask(irq);
+}
+
+/**
+ * handle_edge_irq - edge type IRQ handler
+ * @irq: the interrupt number
+ * @desc: the interrupt description structure for this irq
+ * @regs: pointer to a register structure
+ *
+ * Interrupt occures on the falling and/or rising edge of a hardware
+ * signal. The occurence is latched into the irq controller hardware
+ * and must be acked in order to be reenabled. After the ack another
+ * interrupt can happen on the same source even before the first one
+ * is handled by the assosiacted event handler. If this happens it
+ * might be necessary to disable (mask) the interrupt depending on the
+ * controller hardware. This requires to reenable the interrupt inside
+ * of the loop which handles the interrupts which have arrived while
+ * the handler was running. If all pending interrupts are handled, the
+ * loop is left and depending on the hardware controller some final
+ * ack might be necessary.
+ *
+ * Must be called with the irq_desc->lock held
+ */
+void
+handle_edge_irq(unsigned int irq, struct irq_desc *desc, struct pt_regs *regs)
+{
+ const unsigned int cpu = smp_processor_id();
+
+ kstat_cpu(cpu).irqs[irq]++;
+
+ desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
+
+ /*
+ * If we're currently running this IRQ, or its disabled,
+ * we shouldn't process the IRQ. Mark it pending, handle
+ * the necessary masking and go out
+ */
+ if (unlikely((desc->status & IRQ_INPROGRESS) || desc->depth ||
+ !desc->action)) {
+ desc->status |= (IRQ_PENDING | IRQ_MASKED);
+ mask_ack_irq(desc, irq);
+ return;
+ }
+
+ /* Start handling the irq */
+ desc->handler->ack(irq);
+
+ /* Mark the IRQ currently in progress.*/
+ desc->status |= IRQ_INPROGRESS;
+
+ do {
+ struct irqaction *action = desc->action;
+ irqreturn_t action_ret;
+
+ if (unlikely(!action)) {
+ desc->handler->mask(irq);
+ return;
+ }
+
+ /*
+ * When another irq arrived while we were handling
+ * one, we could have masked the irq.
+ * Renable it, if it was not disabled in meantime.
+ */
+ if (unlikely(((desc->status & (IRQ_PENDING | IRQ_MASKED)) ==
+ (IRQ_PENDING | IRQ_MASKED)) && !desc->depth)) {
+ desc->handler->unmask(irq);
+ desc->status &= ~IRQ_MASKED;
+ }
+
+ desc->status &= ~IRQ_PENDING;
+ spin_unlock(&desc->lock);
+ action_ret = handle_IRQ_event(irq, regs, action);
+ if (!noirqdebug)
+ note_interrupt(irq, desc, action_ret, regs);
+ spin_lock(&desc->lock);
+
+ } while ((desc->status & IRQ_PENDING) && !desc->depth);
+
+ desc->status &= ~IRQ_INPROGRESS;
+}
+
+#ifdef CONFIG_SMP
+/**
+ * handle_percpu_IRQ - Per CPU local irq handler
+ * @irq: the interrupt number
+ * @desc: the interrupt description structure for this irq
+ * @regs: pointer to a register structure
+ *
+ * Per CPU interrupts on SMP machines without locking requirements
+ */
+void
+handle_percpu_irq(unsigned int irq, struct irq_desc *desc, struct pt_regs *regs)
+{
+ irqreturn_t action_ret;
+
+ kstat_this_cpu.irqs[irq]++;
+
+ if (desc->handler->ack)
+ desc->handler->ack(irq);
+
+ action_ret = handle_IRQ_event(irq, regs, desc->action);
+ if (!noirqdebug)
+ note_interrupt(irq, desc, action_ret, regs);
+
+ if (desc->handler->end)
+ desc->handler->end(irq);
+}
+#endif /* CONFIG_SMP */
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
