--- /dev/null
+/* irq.c: FRV IRQ handling
+ *
+ * Copyright (C) 2003, 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * 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.
+ */
+
+/*
+ * (mostly architecture independent, will move to kernel/irq.c in 2.5.)
+ *
+ * IRQs 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/ptrace.h>
+#include <linux/errno.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/smp_lock.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/irq.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+#include <asm/atomic.h>
+#include <asm/io.h>
+#include <asm/smp.h>
+#include <asm/system.h>
+#include <asm/bitops.h>
+#include <asm/uaccess.h>
+#include <asm/pgalloc.h>
+#include <asm/delay.h>
+#include <asm/irq.h>
+#include <asm/irc-regs.h>
+#include <asm/irq-routing.h>
+#include <asm/gdb-stub.h>
+
+extern void __init fpga_init(void);
+extern void __init route_mb93493_irqs(void);
+
+static void register_irq_proc (unsigned int irq);
+
+/*
+ * Special irq handlers.
+ */
+
+irqreturn_t no_action(int cpl, void *dev_id, struct pt_regs *regs) { return IRQ_HANDLED; }
+
+atomic_t irq_err_count;
+
+/*
+ * Generic, controller-independent functions:
+ */
+int show_interrupts(struct seq_file *p, void *v)
+{
+ struct irqaction *action;
+ struct irq_group *group;
+ unsigned long flags;
+ int level, grp, ix, i, j;
+
+ i = *(loff_t *) v;
+
+ switch (i) {
+ case 0:
+ seq_printf(p, " ");
+ for (j = 0; j < NR_CPUS; j++)
+ if (cpu_online(j))
+ seq_printf(p, "CPU%d ",j);
+
+ seq_putc(p, '\n');
+ break;
+
+ case 1 ... NR_IRQ_GROUPS * NR_IRQ_ACTIONS_PER_GROUP:
+ local_irq_save(flags);
+
+ grp = (i - 1) / NR_IRQ_ACTIONS_PER_GROUP;
+ group = irq_groups[grp];
+ if (!group)
+ goto skip;
+
+ ix = (i - 1) % NR_IRQ_ACTIONS_PER_GROUP;
+ action = group->actions[ix];
+ if (!action)
+ goto skip;
+
+ seq_printf(p, "%3d: ", i - 1);
+
+#ifndef CONFIG_SMP
+ seq_printf(p, "%10u ", kstat_irqs(i));
+#else
+ for (j = 0; j < NR_CPUS; j++)
+ if (cpu_online(j))
+ seq_printf(p, "%10u ", kstat_cpu(j).irqs[i - 1]);
+#endif
+
+ level = group->sources[ix]->level - frv_irq_levels;
+
+ seq_printf(p, " %12s@%x", group->sources[ix]->muxname, level);
+ seq_printf(p, " %s", action->name);
+
+ for (action = action->next; action; action = action->next)
+ seq_printf(p, ", %s", action->name);
+
+ seq_putc(p, '\n');
+skip:
+ local_irq_restore(flags);
+ break;
+
+ case NR_IRQ_GROUPS * NR_IRQ_ACTIONS_PER_GROUP + 1:
+ seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
+ break;
+
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+
+/*
+ * Generic enable/disable code: this just calls
+ * down into the PIC-specific version for the actual
+ * hardware disable after having gotten the irq
+ * controller lock.
+ */
+
+/**
+ * disable_irq_nosync - disable an irq without waiting
+ * @irq: Interrupt to disable
+ *
+ * Disable the selected interrupt line. Disables and Enables are
+ * nested.
+ * Unlike disable_irq(), this function does not ensure existing
+ * instances of the IRQ handler have completed before returning.
+ *
+ * This function may be called from IRQ context.
+ */
+
+void disable_irq_nosync(unsigned int irq)
+{
+ struct irq_source *source;
+ struct irq_group *group;
+ struct irq_level *level;
+ unsigned long flags;
+ int idx = irq & (NR_IRQ_ACTIONS_PER_GROUP - 1);
+
+ group = irq_groups[irq >> NR_IRQ_LOG2_ACTIONS_PER_GROUP];
+ if (!group)
+ BUG();
+
+ source = group->sources[idx];
+ if (!source)
+ BUG();
+
+ level = source->level;
+
+ spin_lock_irqsave(&level->lock, flags);
+
+ if (group->control) {
+ if (!group->disable_cnt[idx]++)
+ group->control(group, idx, 0);
+ } else if (!level->disable_count++) {
+ __set_MASK(level - frv_irq_levels);
+ }
+
+ spin_unlock_irqrestore(&level->lock, flags);
+}
+
+/**
+ * disable_irq - disable an irq and wait for completion
+ * @irq: Interrupt to disable
+ *
+ * Disable the selected interrupt line. Enables and Disables are
+ * nested.
+ * This function waits for any pending IRQ handlers for this interrupt
+ * to complete before returning. If you use this function while
+ * holding a resource the IRQ handler may need you will deadlock.
+ *
+ * This function may be called - with care - from IRQ context.
+ */
+
+void disable_irq(unsigned int irq)
+{
+ disable_irq_nosync(irq);
+
+#ifdef CONFIG_SMP
+ if (!local_irq_count(smp_processor_id())) {
+ do {
+ barrier();
+ } while (irq_desc[irq].status & IRQ_INPROGRESS);
+ }
+#endif
+}
+
+/**
+ * enable_irq - enable handling of an irq
+ * @irq: Interrupt to enable
+ *
+ * Undoes the effect of one call to disable_irq(). If this
+ * matches the last disable, processing of interrupts on this
+ * IRQ line is re-enabled.
+ *
+ * This function may be called from IRQ context.
+ */
+
+void enable_irq(unsigned int irq)
+{
+ struct irq_source *source;
+ struct irq_group *group;
+ struct irq_level *level;
+ unsigned long flags;
+ int idx = irq & (NR_IRQ_ACTIONS_PER_GROUP - 1);
+ int count;
+
+ group = irq_groups[irq >> NR_IRQ_LOG2_ACTIONS_PER_GROUP];
+ if (!group)
+ BUG();
+
+ source = group->sources[idx];
+ if (!source)
+ BUG();
+
+ level = source->level;
+
+ spin_lock_irqsave(&level->lock, flags);
+
+ if (group->control)
+ count = group->disable_cnt[idx];
+ else
+ count = level->disable_count;
+
+ switch (count) {
+ case 1:
+ if (group->control) {
+ if (group->actions[idx])
+ group->control(group, idx, 1);
+ } else {
+ if (level->usage)
+ __clr_MASK(level - frv_irq_levels);
+ }
+ /* fall-through */
+
+ default:
+ count--;
+ break;
+
+ case 0:
+ printk("enable_irq(%u) unbalanced from %p\n", irq, __builtin_return_address(0));
+ }
+
+ if (group->control)
+ group->disable_cnt[idx] = count;
+ else
+ level->disable_count = count;
+
+ spin_unlock_irqrestore(&level->lock, flags);
+}
+
+/*****************************************************************************/
+/*
+ * handles all normal device IRQ's
+ * - registers are referred to by the __frame variable (GR28)
+ * - IRQ distribution is complicated in this arch because of the many PICs, the
+ * way they work and the way they cascade
+ */
+asmlinkage void do_IRQ(void)
+{
+ struct irq_source *source;
+ int level, cpu;
+
+ level = (__frame->tbr >> 4) & 0xf;
+ cpu = smp_processor_id();
+
+#if 0
+ {
+ static u32 irqcount;
+ *(volatile u32 *) 0xe1200004 = ~((irqcount++ << 8) | level);
+ *(volatile u16 *) 0xffc00100 = (u16) ~0x9999;
+ mb();
+ }
+#endif
+
+ if ((unsigned long) __frame - (unsigned long) (current + 1) < 512)
+ BUG();
+
+ __set_MASK(level);
+ __clr_RC(level);
+ __clr_IRL();
+
+ kstat_this_cpu.irqs[level]++;
+
+ irq_enter();
+
+ for (source = frv_irq_levels[level].sources; source; source = source->next)
+ source->doirq(source);
+
+ irq_exit();
+
+ __clr_MASK(level);
+
+ /* only process softirqs if we didn't interrupt another interrupt handler */
+ if ((__frame->psr & PSR_PIL) == PSR_PIL_0)
+ if (local_softirq_pending())
+ do_softirq();
+
+#ifdef CONFIG_PREEMPT
+ local_irq_disable();
+ while (--current->preempt_count == 0) {
+ if (!(__frame->psr & PSR_S) ||
+ current->need_resched == 0 ||
+ in_interrupt())
+ break;
+ current->preempt_count++;
+ local_irq_enable();
+ preempt_schedule();
+ local_irq_disable();
+ }
+#endif
+
+#if 0
+ {
+ *(volatile u16 *) 0xffc00100 = (u16) ~0x6666;
+ mb();
+ }
+#endif
+
+} /* end do_IRQ() */
+
+/*****************************************************************************/
+/*
+ * handles all NMIs when not co-opted by the debugger
+ * - registers are referred to by the __frame variable (GR28)
+ */
+asmlinkage void do_NMI(void)
+{
+} /* end do_NMI() */
+
+/*****************************************************************************/
+/**
+ * request_irq - allocate an interrupt line
+ * @irq: Interrupt line to allocate
+ * @handler: Function to be called when the IRQ occurs
+ * @irqflags: Interrupt type flags
+ * @devname: An ascii name for the claiming device
+ * @dev_id: A cookie passed back to the handler function
+ *
+ * This call allocates interrupt resources and enables the
+ * interrupt line and IRQ handling. From the point this
+ * call is made your handler function may be invoked. Since
+ * your handler function must clear any interrupt the board
+ * raises, you must take care both to initialise your hardware
+ * and to set up the interrupt handler in the right order.
+ *
+ * Dev_id must be globally unique. Normally the address of the
+ * device data structure is used as the cookie. Since the handler
+ * receives this value it makes sense to use it.
+ *
+ * If your interrupt is shared you must pass a non NULL dev_id
+ * as this is required when freeing the interrupt.
+ *
+ * Flags:
+ *
+ * SA_SHIRQ Interrupt is shared
+ *
+ * SA_INTERRUPT Disable local interrupts while processing
+ *
+ * SA_SAMPLE_RANDOM The interrupt can be used for 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 1
+ /*
+ * Sanity-check: shared interrupts should REALLY pass in
+ * a real dev-ID, otherwise we'll have trouble later trying
+ * to figure out which interrupt is which (messes up the
+ * interrupt freeing logic etc).
+ */
+ if (irqflags & SA_SHIRQ) {
+ if (!dev_id)
+ printk("Bad boy: %s (at 0x%x) called us without a dev_id!\n",
+ devname, (&irq)[-1]);
+ }
+#endif
+
+ if ((irq >> NR_IRQ_LOG2_ACTIONS_PER_GROUP) >= NR_IRQ_GROUPS)
+ return -EINVAL;
+ if (!handler)
+ return -EINVAL;
+
+ action = (struct irqaction *) kmalloc(sizeof(struct irqaction), GFP_KERNEL);
+ if (!action)
+ return -ENOMEM;
+
+ action->handler = handler;
+ action->flags = irqflags;
+ action->mask = CPU_MASK_NONE;
+ action->name = devname;
+ action->next = NULL;
+ action->dev_id = dev_id;
+
+ retval = setup_irq(irq, action);
+ if (retval)
+ kfree(action);
+ return retval;
+}
+
+/**
+ * free_irq - free an interrupt
+ * @irq: Interrupt line to free
+ * @dev_id: Device identity to free
+ *
+ * Remove an interrupt handler. The handler is removed and if the
+ * interrupt line is no longer in use by any driver it is disabled.
+ * On a shared IRQ the caller must ensure the interrupt is disabled
+ * on the card it drives before calling this function. The function
+ * does not return until any executing interrupts for this IRQ
+ * have completed.
+ *
+ * This function may be called from interrupt context.
+ *
+ * Bugs: Attempting to free an irq in a handler for the same irq hangs
+ * the machine.
+ */
+
+void free_irq(unsigned int irq, void *dev_id)
+{
+ struct irq_source *source;
+ struct irq_group *group;
+ struct irq_level *level;
+ struct irqaction **p, **pp;
+ unsigned long flags;
+
+ if ((irq >> NR_IRQ_LOG2_ACTIONS_PER_GROUP) >= NR_IRQ_GROUPS)
+ return;
+
+ group = irq_groups[irq >> NR_IRQ_LOG2_ACTIONS_PER_GROUP];
+ if (!group)
+ BUG();
+
+ source = group->sources[irq & (NR_IRQ_ACTIONS_PER_GROUP - 1)];
+ if (!source)
+ BUG();
+
+ level = source->level;
+ p = &group->actions[irq & (NR_IRQ_ACTIONS_PER_GROUP - 1)];
+
+ spin_lock_irqsave(&level->lock, flags);
+
+ for (pp = p; *pp; pp = &(*pp)->next) {
+ struct irqaction *action = *pp;
+
+ if (action->dev_id != dev_id)
+ continue;
+
+ /* found it - remove from the list of entries */
+ *pp = action->next;
+
+ level->usage--;
+
+ if (p == pp && group->control)
+ group->control(group, irq & (NR_IRQ_ACTIONS_PER_GROUP - 1), 0);
+
+ if (level->usage == 0)
+ __set_MASK(level - frv_irq_levels);
+
+ spin_unlock_irqrestore(&level->lock,flags);
+
+#ifdef CONFIG_SMP
+ /* Wait to make sure it's not being used on another CPU */
+ while (desc->status & IRQ_INPROGRESS)
+ barrier();
+#endif
+ kfree(action);
+ return;
+ }
+}
+
+/*
+ * IRQ autodetection code..
+ *
+ * This depends on the fact that any interrupt that comes in on to an
+ * unassigned IRQ will cause GxICR_DETECT to be set
+ */
+
+static DECLARE_MUTEX(probe_sem);
+
+/**
+ * probe_irq_on - begin an interrupt autodetect
+ *
+ * Commence probing for an interrupt. The interrupts are scanned
+ * and a mask of potential interrupt lines is returned.
+ *
+ */
+
+unsigned long probe_irq_on(void)
+{
+ down(&probe_sem);
+ return 0;
+}
+
+/*
+ * Return a mask of triggered interrupts (this
+ * can handle only legacy ISA interrupts).
+ */
+
+/**
+ * probe_irq_mask - scan a bitmap of interrupt lines
+ * @val: mask of interrupts to consider
+ *
+ * Scan the ISA bus interrupt lines and return a bitmap of
+ * active interrupts. The interrupt probe logic state is then
+ * returned to its previous value.
+ *
+ * Note: we need to scan all the irq's even though we will
+ * only return ISA irq numbers - just so that we reset them
+ * all to a known state.
+ */
+unsigned int probe_irq_mask(unsigned long xmask)
+{
+ up(&probe_sem);
+ return 0;
+}
+
+/*
+ * Return the one interrupt that triggered (this can
+ * handle any interrupt source).
+ */
+
+/**
+ * probe_irq_off - end an interrupt autodetect
+ * @xmask: mask of potential interrupts (unused)
+ *
+ * Scans the unused interrupt lines and returns the line which
+ * appears to have triggered the interrupt. If no interrupt was
+ * found then zero is returned. If more than one interrupt is
+ * found then minus the first candidate is returned to indicate
+ * their is doubt.
+ *
+ * The interrupt probe logic state is returned to its previous
+ * value.
+ *
+ * BUGS: When used in a module (which arguably shouldnt happen)
+ * nothing prevents two IRQ probe callers from overlapping. The
+ * results of this are non-optimal.
+ */
+
+int probe_irq_off(unsigned long xmask)
+{
+ up(&probe_sem);
+ return -1;
+}
+
+/* this was setup_x86_irq but it seems pretty generic */
+int setup_irq(unsigned int irq, struct irqaction *new)
+{
+ struct irq_source *source;
+ struct irq_group *group;
+ struct irq_level *level;
+ struct irqaction **p, **pp;
+ unsigned long flags;
+
+ group = irq_groups[irq >> NR_IRQ_LOG2_ACTIONS_PER_GROUP];
+ if (!group)
+ BUG();
+
+ source = group->sources[irq & (NR_IRQ_ACTIONS_PER_GROUP - 1)];
+ if (!source)
+ BUG();
+
+ level = source->level;
+
+ p = &group->actions[irq & (NR_IRQ_ACTIONS_PER_GROUP - 1)];
+
+ /*
+ * Some drivers like serial.c use request_irq() heavily,
+ * so we have to be careful not to interfere with a
+ * running system.
+ */
+ if (new->flags & SA_SAMPLE_RANDOM) {
+ /*
+ * This function might sleep, we want to call it first,
+ * outside of the atomic block.
+ * Yes, this might clear the entropy pool if the wrong
+ * driver is attempted to be loaded, without actually
+ * installing a new handler, but is this really a problem,
+ * only the sysadmin is able to do this.
+ */
+ rand_initialize_irq(irq);
+ }
+
+ /* must juggle the interrupt processing stuff with interrupts disabled */
+ spin_lock_irqsave(&level->lock, flags);
+
+ /* can't share interrupts unless all parties agree to */
+ if (level->usage != 0 && !(level->flags & new->flags & SA_SHIRQ)) {
+ spin_unlock_irqrestore(&level->lock,flags);
+ return -EBUSY;
+ }
+
+ /* add new interrupt at end of irq queue */
+ pp = p;
+ while (*pp)
+ pp = &(*pp)->next;
+
+ *pp = new;
+
+ level->usage++;
+ level->flags = new->flags;
+
+ /* turn the interrupts on */
+ if (level->usage == 1)
+ __clr_MASK(level - frv_irq_levels);
+
+ if (p == pp && group->control)
+ group->control(group, irq & (NR_IRQ_ACTIONS_PER_GROUP - 1), 1);
+
+ spin_unlock_irqrestore(&level->lock, flags);
+ register_irq_proc(irq);
+ return 0;
+}
+
+static struct proc_dir_entry * root_irq_dir;
+static struct proc_dir_entry * irq_dir [NR_IRQS];
+
+#define HEX_DIGITS 8
+
+static unsigned int parse_hex_value (const char *buffer,
+ unsigned long count, unsigned long *ret)
+{
+ unsigned char hexnum [HEX_DIGITS];
+ unsigned long value;
+ int i;
+
+ if (!count)
+ return -EINVAL;
+ if (count > HEX_DIGITS)
+ count = HEX_DIGITS;
+ if (copy_from_user(hexnum, buffer, count))
+ return -EFAULT;
+
+ /*
+ * Parse the first 8 characters as a hex string, any non-hex char
+ * is end-of-string. '00e1', 'e1', '00E1', 'E1' are all the same.
+ */
+ value = 0;
+
+ for (i = 0; i < count; i++) {
+ unsigned int c = hexnum[i];
+
+ switch (c) {
+ case '0' ... '9': c -= '0'; break;
+ case 'a' ... 'f': c -= 'a'-10; break;
+ case 'A' ... 'F': c -= 'A'-10; break;
+ default:
+ goto out;
+ }
+ value = (value << 4) | c;
+ }
+out:
+ *ret = value;
+ return 0;
+}
+
+
+static int prof_cpu_mask_read_proc (char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ unsigned long *mask = (unsigned long *) data;
+ if (count < HEX_DIGITS+1)
+ return -EINVAL;
+ return sprintf (page, "%08lx\n", *mask);
+}
+
+static int prof_cpu_mask_write_proc (struct file *file, const char *buffer,
+ unsigned long count, void *data)
+{
+ unsigned long *mask = (unsigned long *) data, full_count = count, err;
+ unsigned long new_value;
+
+ show_state();
+ err = parse_hex_value(buffer, count, &new_value);
+ if (err)
+ return err;
+
+ *mask = new_value;
+ return full_count;
+}
+
+#define MAX_NAMELEN 10
+
+static void register_irq_proc (unsigned int irq)
+{
+ char name [MAX_NAMELEN];
+
+ if (!root_irq_dir || irq_dir[irq])
+ return;
+
+ memset(name, 0, MAX_NAMELEN);
+ sprintf(name, "%d", irq);
+
+ /* create /proc/irq/1234 */
+ irq_dir[irq] = proc_mkdir(name, root_irq_dir);
+}
+
+unsigned long prof_cpu_mask = -1;
+
+void init_irq_proc (void)
+{
+ struct proc_dir_entry *entry;
+ int i;
+
+ /* create /proc/irq */
+ root_irq_dir = proc_mkdir("irq", 0);
+
+ /* create /proc/irq/prof_cpu_mask */
+ entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir);
+ if (!entry)
+ return;
+
+ entry->nlink = 1;
+ entry->data = (void *)&prof_cpu_mask;
+ entry->read_proc = prof_cpu_mask_read_proc;
+ entry->write_proc = prof_cpu_mask_write_proc;
+
+ /*
+ * Create entries for all existing IRQs.
+ */
+ for (i = 0; i < NR_IRQS; i++)
+ register_irq_proc(i);
+}
+
+/*****************************************************************************/
+/*
+ * initialise the interrupt system
+ */
+void __init init_IRQ(void)
+{
+ route_cpu_irqs();
+ fpga_init();
+#ifdef CONFIG_FUJITSU_MB93493
+ route_mb93493_irqs();
+#endif
+} /* end init_IRQ() */
git://git.onelab.eu / linux-2.6.git / blobdiff