Linux-2.6.12-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!

1 files changed, 764 insertions, 0 deletions

diff --git a/arch/frv/kernel/irq.c b/arch/frv/kernel/irq.c
new file mode 100644
index 0000000..8c524cd
--- /dev/null
+++ b/arch/frv/kernel/irq.c
@@ -0,0 +1,764 @@
+/* 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() */