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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/cris/kernel/irq.c
downloadlinux-stericsson-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/cris/kernel/irq.c')
-rw-r--r--arch/cris/kernel/irq.c297
1 files changed, 297 insertions, 0 deletions
diff --git a/arch/cris/kernel/irq.c b/arch/cris/kernel/irq.c
new file mode 100644
index 000000000000..d848b9407457
--- /dev/null
+++ b/arch/cris/kernel/irq.c
@@ -0,0 +1,297 @@
+/*
+ *
+ * linux/arch/cris/kernel/irq.c
+ *
+ * Copyright (c) 2000,2001 Axis Communications AB
+ *
+ * Authors: Bjorn Wesen (bjornw@axis.com)
+ *
+ * This file contains the code used by various IRQ handling routines:
+ * asking for different IRQ's should be done through these routines
+ * instead of just grabbing them. Thus setups with different IRQ numbers
+ * shouldn't result in any weird surprises, and installing new handlers
+ * should be easier.
+ *
+ * Notice Linux/CRIS: these routines do not care about SMP
+ *
+ */
+
+/*
+ * IRQ's are in fact implemented a bit like signal handlers for the kernel.
+ * Naturally it's not a 1:1 relation, but there are similarities.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/ptrace.h>
+
+#include <linux/kernel_stat.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/timex.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/errno.h>
+#include <linux/bitops.h>
+
+#include <asm/io.h>
+
+/* Defined in arch specific irq.c */
+extern void arch_setup_irq(int irq);
+extern void arch_free_irq(int irq);
+
+void
+disable_irq(unsigned int irq_nr)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+ local_irq_disable();
+ mask_irq(irq_nr);
+ local_irq_restore(flags);
+}
+
+void
+enable_irq(unsigned int irq_nr)
+{
+ unsigned long flags;
+ local_save_flags(flags);
+ local_irq_disable();
+ unmask_irq(irq_nr);
+ local_irq_restore(flags);
+}
+
+unsigned long
+probe_irq_on()
+{
+ return 0;
+}
+
+EXPORT_SYMBOL(probe_irq_on);
+
+int
+probe_irq_off(unsigned long x)
+{
+ return 0;
+}
+
+EXPORT_SYMBOL(probe_irq_off);
+
+/*
+ * Initial irq handlers.
+ */
+
+static struct irqaction *irq_action[NR_IRQS];
+
+int show_interrupts(struct seq_file *p, void *v)
+{
+ int i = *(loff_t *) v;
+ struct irqaction * action;
+ unsigned long flags;
+
+ if (i < NR_IRQS) {
+ local_irq_save(flags);
+ action = irq_action[i];
+ if (!action)
+ goto skip;
+ seq_printf(p, "%2d: %10u %c %s",
+ i, kstat_this_cpu.irqs[i],
+ (action->flags & SA_INTERRUPT) ? '+' : ' ',
+ action->name);
+ for (action = action->next; action; action = action->next) {
+ seq_printf(p, ",%s %s",
+ (action->flags & SA_INTERRUPT) ? " +" : "",
+ action->name);
+ }
+ seq_putc(p, '\n');
+skip:
+ local_irq_restore(flags);
+ }
+ return 0;
+}
+
+/* called by the assembler IRQ entry functions defined in irq.h
+ * to dispatch the interrupts to registred handlers
+ * interrupts are disabled upon entry - depending on if the
+ * interrupt was registred with SA_INTERRUPT or not, interrupts
+ * are re-enabled or not.
+ */
+
+asmlinkage void do_IRQ(int irq, struct pt_regs * regs)
+{
+ struct irqaction *action;
+ int do_random, cpu;
+ int ret, retval = 0;
+
+ cpu = smp_processor_id();
+ irq_enter();
+ kstat_cpu(cpu).irqs[irq - FIRST_IRQ]++;
+ action = irq_action[irq - FIRST_IRQ];
+
+ if (action) {
+ if (!(action->flags & SA_INTERRUPT))
+ local_irq_enable();
+ do_random = 0;
+ do {
+ ret = action->handler(irq, action->dev_id, regs);
+ if (ret == IRQ_HANDLED)
+ do_random |= action->flags;
+ retval |= ret;
+ action = action->next;
+ } while (action);
+
+ if (retval != 1) {
+ if (retval) {
+ printk("irq event %d: bogus retval mask %x\n",
+ irq, retval);
+ } else {
+ printk("irq %d: nobody cared\n", irq);
+ }
+ }
+
+ if (do_random & SA_SAMPLE_RANDOM)
+ add_interrupt_randomness(irq);
+ local_irq_disable();
+ }
+ irq_exit();
+}
+
+/* this function links in a handler into the chain of handlers for the
+ given irq, and if the irq has never been registred, the appropriate
+ handler is entered into the interrupt vector
+*/
+
+int setup_irq(int irq, struct irqaction * new)
+{
+ int shared = 0;
+ struct irqaction *old, **p;
+ unsigned long flags;
+
+ p = irq_action + irq - FIRST_IRQ;
+ if ((old = *p) != NULL) {
+ /* Can't share interrupts unless both agree to */
+ if (!(old->flags & new->flags & SA_SHIRQ))
+ return -EBUSY;
+
+ /* Can't share interrupts unless both are same type */
+ if ((old->flags ^ new->flags) & SA_INTERRUPT)
+ return -EBUSY;
+
+ /* add new interrupt at end of irq queue */
+ do {
+ p = &old->next;
+ old = *p;
+ } while (old);
+ shared = 1;
+ }
+
+ if (new->flags & SA_SAMPLE_RANDOM)
+ rand_initialize_irq(irq);
+
+ local_save_flags(flags);
+ local_irq_disable();
+ *p = new;
+
+ if (!shared) {
+ /* if the irq wasn't registred before, enter it into the vector table
+ and unmask it physically
+ */
+ arch_setup_irq(irq);
+ unmask_irq(irq);
+ }
+
+ local_irq_restore(flags);
+ return 0;
+}
+
+/* this function is called by a driver to register an irq handler
+ Valid flags:
+ SA_INTERRUPT -> it's a fast interrupt, handler called with irq disabled and
+ no signal checking etc is performed upon exit
+ SA_SHIRQ -> the interrupt can be shared between different handlers, the handler
+ is required to check if the irq was "aimed" at it explicitely
+ SA_RANDOM -> the interrupt will add to the random generators entropy
+*/
+
+int request_irq(unsigned int irq,
+ irqreturn_t (*handler)(int, void *, struct pt_regs *),
+ unsigned long irqflags,
+ const char * devname,
+ void *dev_id)
+{
+ int retval;
+ struct irqaction * action;
+
+ if(!handler)
+ return -EINVAL;
+
+ /* allocate and fill in a handler structure and setup the irq */
+
+ action = (struct irqaction *)kmalloc(sizeof(struct irqaction), GFP_KERNEL);
+ if (!action)
+ return -ENOMEM;
+
+ action->handler = handler;
+ action->flags = irqflags;
+ cpus_clear(action->mask);
+ action->name = devname;
+ action->next = NULL;
+ action->dev_id = dev_id;
+
+ retval = setup_irq(irq, action);
+
+ if (retval)
+ kfree(action);
+ return retval;
+}
+
+EXPORT_SYMBOL(request_irq);
+
+void free_irq(unsigned int irq, void *dev_id)
+{
+ struct irqaction * action, **p;
+ unsigned long flags;
+
+ if (irq >= NR_IRQS) {
+ printk("Trying to free IRQ%d\n",irq);
+ return;
+ }
+ for (p = irq - FIRST_IRQ + irq_action; (action = *p) != NULL; p = &action->next) {
+ if (action->dev_id != dev_id)
+ continue;
+
+ /* Found it - now free it */
+ local_save_flags(flags);
+ local_irq_disable();
+ *p = action->next;
+ if (!irq_action[irq - FIRST_IRQ]) {
+ mask_irq(irq);
+ arch_free_irq(irq);
+ }
+ local_irq_restore(flags);
+ kfree(action);
+ return;
+ }
+ printk("Trying to free free IRQ%d\n",irq);
+}
+
+EXPORT_SYMBOL(free_irq);
+
+void weird_irq(void)
+{
+ local_irq_disable();
+ printk("weird irq\n");
+ while(1);
+}
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_SYSCTL)
+/* Used by other archs to show/control IRQ steering during SMP */
+void __init
+init_irq_proc(void)
+{
+}
+#endif