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* [PATCH] irq handling code consolidation (common part)
@ 2003-01-21 10:45 Andrey Panin
  2003-01-21 10:51 ` [PATCH] irq handling code consolidation (i386 part) Andrey Panin
                   ` (4 more replies)
  0 siblings, 5 replies; 9+ messages in thread
From: Andrey Panin @ 2003-01-21 10:45 UTC (permalink / raw)
  To: linux-kernel; +Cc: pazke

[-- Attachment #1: Type: text/plain, Size: 468 bytes --]

Hi all,

this is a 3rd try on irq handling consolidation work.
Patch creates common kernel/irq.c which is used by following
arch specific patches.

Please take a look at it. Comments are welcome (especially from 
arch maintainers)

BTW is here a possibility that this code will be accepted or
feature freeze denies it and i'm wasting everyone's time ?

Best regards.

-- 
Andrey Panin		| Embedded systems software developer
pazke@orbita1.ru	| PGP key: wwwkeys.pgp.net

[-- Attachment #2: patch-irq-common-2.5.59 --]
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diff --minimal -urN -X /usr/share/dontdiff linux-2.5.59.vanilla/kernel/Makefile linux-2.5.59/kernel/Makefile
--- linux-2.5.59.vanilla/kernel/Makefile	Mon Jan 20 13:42:57 2003
+++ linux-2.5.59/kernel/Makefile	Mon Jan 20 13:57:36 2003
@@ -22,6 +22,7 @@
 obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
 obj-$(CONFIG_SOFTWARE_SUSPEND) += suspend.o
 obj-$(CONFIG_COMPAT) += compat.o
+obj-$(CONFIG_GENERIC_IRQ) += irq.o
 
 ifneq ($(CONFIG_IA64),y)
 # According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
diff --minimal -urN -X /usr/share/dontdiff linux-2.5.59.vanilla/kernel/irq.c linux-2.5.59/kernel/irq.c
--- linux-2.5.59.vanilla/kernel/irq.c	Thu Jan  1 03:00:00 1970
+++ linux-2.5.59/kernel/irq.c	Tue Jan 21 19:42:03 2003
@@ -0,0 +1,810 @@
+/*
+ *  linux/kernel/irq.c
+ *
+ *  Architecture independent parts of IRQ handling.
+ *
+ *  Copyright (C) 1992-2002 Linus Torvalds.
+ *
+ *  Modified from the alpha version by Andrey Panin.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+/*
+ * 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.
+ *
+ * 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.
+ *
+ * Linux has a controller-independent x86 interrupt architecture.
+ * every controller has a 'controller-template', that is used
+ * by the main code to do the right thing. Each driver-visible
+ * interrupt source is transparently wired to the apropriate
+ * controller. Thus drivers need not be aware of the
+ * interrupt-controller.
+ *
+ * The code is designed to be easily extended with new/different
+ * interrupt controllers, without having to do assembly magic.
+ */
+
+#include <linux/config.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/random.h>
+#include <linux/jiffies.h>
+#include <linux/proc_fs.h>
+#include <linux/stringify.h>
+
+#include <asm/param.h>
+#include <asm/semaphore.h>
+#include <asm/hw_irq.h>
+#include <asm/uaccess.h>
+
+#ifndef HAVE_ARCH_IRQ_DESC
+
+/*
+ * Controller mappings for all interrupt sources:
+ */
+irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned = {
+	[0 ... NR_IRQS - 1] = {
+		.handler =	&no_irq_type,
+		.lock =		SPIN_LOCK_UNLOCKED,
+	}
+};
+
+#endif
+
+/*
+ * Special irq handlers.
+ */
+
+void no_action(int cpl, void *dev_id, struct pt_regs *regs) { }
+
+/*
+ * Generic no controller code
+ */
+atomic_t irq_err_count;
+
+static void no_irq_enable_disable(unsigned int irq) { }
+static unsigned int no_irq_startup(unsigned int irq) { return 0; }
+
+static void no_irq_ack(unsigned int irq)
+{
+	atomic_inc(&irq_err_count);
+	printk(KERN_CRIT "Unexpected IRQ trap at vector %u\n", irq);
+	arch_ack_bad_irq(irq);
+}
+
+struct hw_interrupt_type no_irq_type = {
+	.typename	= "none",
+	.startup	= no_irq_startup,
+	.shutdown	= no_irq_enable_disable,
+	.enable		= no_irq_enable_disable,
+	.disable	= no_irq_enable_disable,
+	.ack		= no_irq_ack,
+	.end		= no_irq_enable_disable,
+};
+
+/*
+ * This should really return information about whether
+ * we should do bottom half handling etc. Right now we
+ * end up _always_ checking the bottom half, which is a
+ * waste of time and is not what some drivers would
+ * prefer.
+ */
+int handle_IRQ_event(unsigned int irq, struct pt_regs *regs,
+		     struct irqaction *action)
+{
+	int status = 1;	/* Force the "do bottom halves" bit */
+
+	if (!(action->flags & SA_INTERRUPT))
+		local_irq_enable();
+
+	do {
+		status |= action->flags;
+		action->handler(irq, action->dev_id, regs);
+		action = action->next;
+	} while (action);
+	if (status & SA_SAMPLE_RANDOM)
+		add_interrupt_randomness(irq);
+	local_irq_disable();
+
+	return status;
+}
+
+#if defined(CONFIG_SMP) && !defined(HAVE_ARCH_SYNCRONIZE_IRQ)
+
+inline void synchronize_irq(unsigned int irq)
+{
+	irq_desc_t *desc = irq_desc(irq);
+
+        /* is there anything to synchronize with? */
+	if (!desc->action)
+		return;
+
+	while (desc->status & IRQ_INPROGRESS)
+		cpu_relax();
+}
+
+#endif
+
+/*
+ * Workarounds for interrupt types without startup()/shutdown() (ppc, ppc64).
+ * Will be removed some day.
+ */
+
+static int startup_irq(unsigned int irq)
+{
+	irq_desc_t *desc = irq_desc(irq);
+
+	if (desc->handler->startup)
+		return desc->handler->startup(irq);
+	else if (desc->handler->enable)
+		desc->handler->enable(irq);
+	else 
+		BUG();
+	return 0;
+}
+
+static void shutdown_irq(unsigned int irq)
+{
+	irq_desc_t *desc = irq_desc(irq);
+
+	if (desc->handler->shutdown)
+		desc->handler->shutdown(irq);
+	else if (desc->handler->disable)
+		desc->handler->disable(irq);
+	else 
+		BUG();
+}
+
+/*
+ * 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.
+ */
+inline void disable_irq_nosync(unsigned int irq)
+{
+	irq_desc_t *desc = irq_desc(irq);
+	unsigned long flags;
+
+	spin_lock_irqsave(&desc->lock, flags);
+	if (!desc->depth++) {
+		/* Needed for ppc & ppc64, doesn't harm others (really ?) */
+		if (!(desc->status & IRQ_PER_CPU))
+			desc->status |= IRQ_DISABLED;
+		desc->handler->disable(irq);
+	}
+	spin_unlock_irqrestore(&desc->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. That is for two disables you need two enables.
+ *	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);
+	synchronize_irq(irq);
+}
+
+/**
+ *	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)
+{
+	irq_desc_t *desc = irq_desc(irq);
+	unsigned long flags;
+
+	spin_lock_irqsave(&desc->lock, flags);
+	switch (desc->depth) {
+	case 1: {
+		unsigned int status = desc->status & ~IRQ_DISABLED;
+		desc->status = status;
+		if ((status & (IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) {
+			desc->status = status | IRQ_REPLAY;
+			hw_resend_irq(desc->handler, irq);
+		}
+		desc->handler->enable(irq);
+		/* fall-through */
+	}
+	default:
+		desc->depth--;
+		break;
+	case 0:
+		printk(KERN_ERR "enable_irq(%u) unbalanced from %p\n",
+		       irq, __builtin_return_address(0));
+	}
+	spin_unlock_irqrestore(&desc->lock, flags);
+}
+
+/**
+ *	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, 
+		void (*handler)(int, void *, struct pt_regs *),
+		unsigned long irqflags, 
+		const char *devname,
+		void *dev_id)
+{
+	int retval;
+	struct irqaction *action;
+
+	/*
+	 * 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(KERN_ERR "Bad boy: %s (at %p) called us " \
+				"without a dev_id!\n", devname,
+				__builtin_return_address(0));
+	}
+
+	if (!irq_valid(irq) || !handler)
+		return -EINVAL;
+
+	action = kmalloc(sizeof(struct irqaction), GFP_ATOMIC);
+	if (!action)
+		return -ENOMEM;
+
+	action->handler = handler;
+	action->flags = irqflags;
+	action->mask = 0;
+	action->name = devname;
+	action->next = NULL;
+	action->dev_id = dev_id;
+
+	retval = setup_irq(irq, action);
+	if (retval)
+		kfree(action);
+	return retval;
+}
+
+#ifndef HAVE_ARCH_IRQ_PROC
+void register_irq_proc(unsigned int irq);
+#endif
+
+int setup_irq(unsigned int irq, struct irqaction *new)
+{
+	int shared = 0;
+	unsigned long flags;
+	struct irqaction *old, **p;
+	irq_desc_t *desc = irq_desc(irq);
+
+	/*
+	 * 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);
+	}
+
+	arch_setup_irq(irq, desc, new);
+
+	/*
+	 * The following block of code has to be executed atomically
+	 */
+	spin_lock_irqsave(&desc->lock, flags);
+	p = &desc->action;
+	if ((old = *p) != NULL) {
+		/* Can't share interrupts unless both agree to */
+		if (!(old->flags & new->flags & SA_SHIRQ)) {
+			spin_unlock_irqrestore(&desc->lock, flags);
+			return -EBUSY;
+		}
+
+		/* add new interrupt at end of irq queue */
+		do {
+			p = &old->next;
+			old = *p;
+		} while (old);
+		shared = 1;
+	}
+
+	*p = new;
+
+	if (!shared) {
+		desc->depth = 0;
+		desc->status &= ARCH_NONSHARED_IRQ_MASK;
+		startup_irq(irq);
+	}
+	spin_unlock_irqrestore(&desc->lock, flags);
+
+	register_irq_proc(irq);
+
+	return 0;
+}
+
+/**
+ *	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 must not be called from interrupt context. 
+ */
+void free_irq(unsigned int irq, void *dev_id)
+{
+	irq_desc_t *desc;
+	struct irqaction **p;
+	unsigned long flags;
+
+	if (!irq_valid(irq)) {
+		printk(KERN_CRIT "Trying to free IRQ%d\n", irq);
+		return;
+	}
+
+	desc = irq_desc(irq);
+	spin_lock_irqsave(&desc->lock, flags);
+	p = &desc->action;
+	for (;;) {
+		struct irqaction * action = *p;
+		if (action) {
+			struct irqaction **pp = p;
+			p = &action->next;
+			if (action->dev_id != dev_id)
+				continue;
+
+			/* Found it - now remove it from the list of entries */
+			*pp = action->next;
+			if (!desc->action) {
+				desc->status |= IRQ_DISABLED;
+				shutdown_irq(irq);
+			}
+			spin_unlock_irqrestore(&desc->lock, flags);
+
+			/* Wait to make sure it's not being used on another CPU */
+			synchronize_irq(irq);
+			kfree(action);
+			return;
+		}
+		printk(KERN_CRIT "Trying to free free IRQ%d\n", irq);
+		spin_unlock_irqrestore(&desc->lock, flags);
+		return;
+	}
+}
+
+#ifndef HAVE_ARCH_IRQ_PROBE
+
+/*
+ * IRQ autodetection code..
+ *
+ * This depends on the fact that any interrupt that
+ * comes in on to an unassigned handler will get stuck
+ * with "IRQ_WAITING" cleared and the interrupt
+ * disabled.
+ */
+
+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)
+{
+	unsigned int i;
+	irq_desc_t *desc;
+	unsigned long val;
+	unsigned long delay;
+
+	down(&probe_sem);
+	/* 
+	 * something may have generated an irq long ago and we want to
+	 * flush such a longstanding irq before considering it as spurious. 
+	 */
+	for (i = NR_IRQS - 1; i > 0; i--)  {
+		desc = irq_desc(i);
+
+		spin_lock_irq(&desc->lock);
+		if (!desc->action) 
+			startup_irq(i);
+		spin_unlock_irq(&desc->lock);
+	}
+
+	/* Wait for longstanding interrupts to trigger. */
+	for (delay = jiffies + HZ/50; time_after(delay, jiffies); )
+		/* about 20ms delay */ barrier();
+
+	/*
+	 * enable any unassigned irqs
+	 * (we must startup again here because if a longstanding irq
+	 * happened in the previous stage, it may have masked itself)
+	 */
+	for (i = NR_IRQS-1; i > 0; i--) {
+		desc = irq_desc(i);
+
+		spin_lock_irq(&desc->lock);
+		if (!desc->action) {
+			desc->status |= IRQ_AUTODETECT | IRQ_WAITING;
+			if (startup_irq(i))
+				desc->status |= IRQ_PENDING;
+		}
+		spin_unlock_irq(&desc->lock);
+	}
+
+	/*
+	 * Wait for spurious interrupts to trigger
+	 */
+	for (delay = jiffies + HZ/10; time_after(delay, jiffies); )
+		/* about 100ms delay */ barrier();
+
+	/*
+	 * Now filter out any obviously spurious interrupts
+	 */
+	val = 0;
+	for (i = 0; i < NR_IRQS; i++) {
+		irq_desc_t *desc = irq_desc(i);
+		unsigned int status;
+
+		spin_lock_irq(&desc->lock);
+		status = desc->status;
+
+		if (status & IRQ_AUTODETECT) {
+			/* It triggered already - consider it spurious. */
+			if (!(status & IRQ_WAITING)) {
+				desc->status = status & ~IRQ_AUTODETECT;
+				shutdown_irq(i);
+			} else
+				if (i < 32)
+					val |= 1 << i;
+		}
+		spin_unlock_irq(&desc->lock);
+	}
+
+	return val;
+}
+
+/**
+ *	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. This function can handle only 
+ *	legacy ISA interrupts
+ *
+ *	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 val)
+{
+	int i;
+	unsigned int mask;
+
+	mask = 0;
+	for (i = 0; i < NR_IRQS; i++) {
+		irq_desc_t *desc = irq_desc(i);
+		unsigned int status;
+
+		spin_lock_irq(&desc->lock);
+		status = desc->status;
+
+		if (status & IRQ_AUTODETECT) {
+			if (i < 16 && !(status & IRQ_WAITING))
+				mask |= 1 << i;
+
+			desc->status = status & ~IRQ_AUTODETECT;
+			shutdown_irq(i);
+		}
+		spin_unlock_irq(&desc->lock);
+	}
+	up(&probe_sem);
+
+	return mask & val;
+}
+
+/**
+ *	probe_irq_off	- end an interrupt autodetect
+ *	@val: 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. This function can handle any interrupt source.
+ *
+ *	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 val)
+{
+	int i, irq_found, nr_irqs;
+
+	nr_irqs = 0;
+	irq_found = 0;
+	for (i = 0; i < NR_IRQS; i++) {
+		irq_desc_t *desc = irq_desc(i);
+		unsigned int status;
+
+		spin_lock_irq(&desc->lock);
+		status = desc->status;
+
+		if (status & IRQ_AUTODETECT) {
+			if (!(status & IRQ_WAITING)) {
+				if (!nr_irqs)
+					irq_found = i;
+				nr_irqs++;
+			}
+			desc->status = status & ~IRQ_AUTODETECT;
+			shutdown_irq(i);
+		}
+		spin_unlock_irq(&desc->lock);
+	}
+	up(&probe_sem);
+
+	if (nr_irqs > 1)
+		irq_found = -irq_found;
+	return irq_found;
+}
+
+#endif	/* HAVE_ARCH_IRQ_PROBE */
+
+#ifndef HAVE_ARCH_IRQ_PROC
+
+unsigned int parse_hex_value(const char *buffer, unsigned long count, 
+			     unsigned long *ret)
+{
+	unsigned char hexnum[ARCH_AFFINITY_WIDTH];
+	unsigned long value, i;
+
+	if (!count)
+		return -EINVAL;
+	if (count > ARCH_AFFINITY_WIDTH)
+		count = ARCH_AFFINITY_WIDTH;
+	if (copy_from_user(hexnum, buffer, count))
+		return -EFAULT;
+
+	/*
+	 * Parse the first ARCH_AFFINITY_WIDTH 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;
+}
+
+#define MAX_NAMELEN 10
+
+struct proc_dir_entry *root_irq_dir;
+static struct proc_dir_entry *irq_dir[NR_IRQS];
+
+#ifdef CONFIG_SMP
+static struct proc_dir_entry *smp_affinity_entry[NR_IRQS];
+
+unsigned long irq_affinity[NR_IRQS] = { 
+	[0 ... NR_IRQS - 1] = ARCH_DEFAULT_IRQ_AFFINITY
+};
+#endif
+
+static int irq_affinity_read_proc(char *page, char **start, off_t off,
+				  int count, int *eof, void *data)
+{
+	if (count < ARCH_AFFINITY_WIDTH + 1)
+		return -EINVAL;
+	return sprintf (page, "%0" __stringify(ARCH_AFFINITY_WIDTH) "lx\n",
+			irq_affinity[(long)data]);
+}
+
+static int irq_affinity_write_proc(struct file *file, const char *buffer,
+				   unsigned long count, void *data)
+{
+	int irq = (long) data, full_count = count, err;
+	unsigned long new_value;
+
+	if (!irq_desc(irq)->handler->set_affinity)
+		return -EIO;
+
+	err = parse_hex_value(buffer, count, &new_value);
+
+	/*
+	 * Do not allow disabling IRQs completely - it's a too easy
+	 * way to make the system unusable accidentally :-) At least
+	 * one online CPU still has to be targeted.
+	 */
+	if (!(new_value & cpu_online_map))
+		return -EINVAL;
+
+	irq_affinity[irq] = new_value;
+	irq_desc(irq)->handler->set_affinity(irq, new_value);
+
+	return full_count;
+}
+
+void register_irq_proc(unsigned int irq)
+{
+	char name[MAX_NAMELEN];
+
+	if (!root_irq_dir || (irq_desc(irq)->handler == &no_irq_type) ||
+			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);
+
+#if CONFIG_SMP
+	if (irq_desc(irq)->handler->set_affinity) {
+		struct proc_dir_entry *entry;
+
+		/* create /proc/irq/1234/smp_affinity */
+		entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]);
+
+		if (entry) {
+			entry->nlink = 1;
+			entry->data = (void *)(long)irq;
+			entry->read_proc = irq_affinity_read_proc;
+			entry->write_proc = irq_affinity_write_proc;
+		}
+
+		smp_affinity_entry[irq] = entry;
+	}
+#endif
+}
+
+unsigned long prof_cpu_mask = ~0UL;
+
+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 < ARCH_AFFINITY_WIDTH + 1)
+		return -EINVAL;
+	return sprintf (page, "%0" __stringify(ARCH_AFFINITY_WIDTH) "lx\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;
+
+	err = parse_hex_value(buffer, count, &new_value);
+	if (err)
+		return err;
+
+	*mask = new_value;
+	return full_count;
+}
+
+void init_irq_proc(void)
+{
+	int i;
+
+	/* create /proc/irq */
+	root_irq_dir = proc_mkdir("irq", 0);
+
+#ifdef CONFIG_SMP
+	{
+		struct proc_dir_entry *entry;
+
+		/* 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;
+	}
+#endif
+
+	/*
+	 * Create entries for all existing IRQs.
+	 */
+	if (arch_can_create_irq_proc())
+		for (i = 0; irq_valid(i); i++)
+			if (irq_desc(i)->handler != &no_irq_type)
+				register_irq_proc(i);
+}
+
+#endif	/* HAVE_ARCH_IRQ_PROC */

^ permalink raw reply	[flat|nested] 9+ messages in thread
* [PATCH] irq handling code consolidation (v850 part)
@ 2003-03-13 13:29 Andrey Panin
  2003-03-14  4:13 ` Miles Bader
  0 siblings, 1 reply; 9+ messages in thread
From: Andrey Panin @ 2003-03-13 13:29 UTC (permalink / raw)
  To: linux-kernel; +Cc: Linus Torvalds, miles

[-- Attachment #1: Type: text/plain, Size: 216 bytes --]

Hi,

irq handling code consolidation continues.

v850 specific patch attached. Untested.

Best regards.

-- 
Andrey Panin		| Embedded systems software developer
pazke@orbita1.ru	| PGP key: wwwkeys.pgp.net

[-- Attachment #2: patch-irq-v850-2.5.64 --]
[-- Type: text/plain, Size: 16657 bytes --]

diff --minimal -urN -X /usr/share/dontdiff linux-2.5.64.vanilla/arch/v850/Kconfig linux-2.5.64/arch/v850/Kconfig
--- linux-2.5.64.vanilla/arch/v850/Kconfig	Mon Mar 10 00:52:00 2003
+++ linux-2.5.64/arch/v850/Kconfig	Tue Mar 11 10:39:02 2003
@@ -16,6 +16,9 @@
 config UID16
 	bool
 	default n
+config GENERIC_IRQ
+	bool
+	default y
 config RWSEM_GENERIC_SPINLOCK
 	bool
 	default y
diff --minimal -urN -X /usr/share/dontdiff linux-2.5.64.vanilla/arch/v850/kernel/irq.c linux-2.5.64/arch/v850/kernel/irq.c
--- linux-2.5.64.vanilla/arch/v850/kernel/irq.c	Mon Mar 10 00:52:27 2003
+++ linux-2.5.64/arch/v850/kernel/irq.c	Tue Mar 11 10:39:02 2003
@@ -25,50 +25,9 @@
 
 #include <asm/system.h>
 
-/*
- * Controller mappings for all interrupt sources:
- */
-irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned =
-	{ [0 ... NR_IRQS-1] = { 0, &no_irq_type, NULL, 0, SPIN_LOCK_UNLOCKED}};
-
-/*
- * Special irq handlers.
- */
-
-void no_action(int cpl, void *dev_id, struct pt_regs *regs) { }
-
-/*
- * Generic no controller code
- */
-
-static void enable_none(unsigned int irq) { }
-static unsigned int startup_none(unsigned int irq) { return 0; }
-static void disable_none(unsigned int irq) { }
-static void ack_none(unsigned int irq)
-{
-	/*
-	 * 'what should we do if we get a hw irq event on an illegal vector'.
-	 * each architecture has to answer this themselves, it doesn't deserve
-	 * a generic callback i think.
-	 */
-	printk("received IRQ %d with unknown interrupt type\n", irq);
-}
-
-/* startup is the same as "enable", shutdown is same as "disable" */
-#define shutdown_none	disable_none
-#define end_none	enable_none
-
-struct hw_interrupt_type no_irq_type = {
-	"none",
-	startup_none,
-	shutdown_none,
-	enable_none,
-	disable_none,
-	ack_none,
-	end_none
-};
+extern atomic_t irq_err_count;
 
-volatile unsigned long irq_err_count, spurious_count;
+volatile unsigned long spurious_count;
 
 /*
  * Generic, controller-independent functions:
@@ -114,122 +73,10 @@
 			seq_printf(p, ", %s", action->name);
 		seq_putc(p, '\n');
 	}
-	seq_printf(p, "ERR: %10lu\n", irq_err_count);
+	seq_printf(p, "ERR: %10lu\n", atomic_read(&irq_err_count));
 	return 0;
 }
 
-/*
- * This should really return information about whether
- * we should do bottom half handling etc. Right now we
- * end up _always_ checking the bottom half, which is a
- * waste of time and is not what some drivers would
- * prefer.
- */
-int handle_IRQ_event(unsigned int irq, struct pt_regs * regs, struct irqaction * action)
-{
-	int status = 1; /* Force the "do bottom halves" bit */
-
-	if (!(action->flags & SA_INTERRUPT))
-		local_irq_enable();
-
-	do {
-		status |= action->flags;
-		action->handler(irq, action->dev_id, regs);
-		action = action->next;
-	} while (action);
-	if (status & SA_SAMPLE_RANDOM)
-		add_interrupt_randomness(irq);
-	local_irq_disable();
-
-	return status;
-}
-
-/*
- * 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 of an interrupt
- *	stack. 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 inline disable_irq_nosync(unsigned int irq)
-{
-	irq_desc_t *desc = irq_desc + irq;
-	unsigned long flags;
-
-	spin_lock_irqsave(&desc->lock, flags);
-	if (!desc->depth++) {
-		desc->status |= IRQ_DISABLED;
-		desc->handler->disable(irq);
-	}
-	spin_unlock_irqrestore(&desc->lock, flags);
-}
-
-/**
- *	disable_irq - disable an irq and wait for completion
- *	@irq: Interrupt to disable
- *
- *	Disable the selected interrupt line. Disables of an interrupt
- *	stack. That is for two disables you need two enables. 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);
-	synchronize_irq(irq);
-}
-
-/**
- *	enable_irq - enable interrupt handling on an irq
- *	@irq: Interrupt to enable
- *
- *	Re-enables the processing of interrupts on this IRQ line
- *	providing no disable_irq calls are now in effect.
- *
- *	This function may be called from IRQ context.
- */
- 
-void enable_irq(unsigned int irq)
-{
-	irq_desc_t *desc = irq_desc + irq;
-	unsigned long flags;
-
-	spin_lock_irqsave(&desc->lock, flags);
-	switch (desc->depth) {
-	case 1: {
-		unsigned int status = desc->status & ~IRQ_DISABLED;
-		desc->status = status;
-		if ((status & (IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) {
-			desc->status = status | IRQ_REPLAY;
-			hw_resend_irq(desc->handler,irq);
-		}
-		desc->handler->enable(irq);
-		/* fall-through */
-	}
-	default:
-		desc->depth--;
-		break;
-	case 0:
-		printk("enable_irq(%u) unbalanced from %p\n", irq,
-		       __builtin_return_address(0));
-	}
-	spin_unlock_irqrestore(&desc->lock, flags);
-}
 
 /* Handle interrupt IRQ.  REGS are the registers at the time of ther
    interrupt.  */
@@ -314,388 +161,6 @@
 	irq_exit();
 
 	return 1;
-}
-
-/**
- *	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, 
-		void (*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_IRQS)
-		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 = 0;
-	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)
-{
-	irq_desc_t *desc;
-	struct irqaction **p;
-	unsigned long flags;
-
-	if (irq >= NR_IRQS)
-		return;
-
-	desc = irq_desc + irq;
-	spin_lock_irqsave(&desc->lock,flags);
-	p = &desc->action;
-	for (;;) {
-		struct irqaction * action = *p;
-		if (action) {
-			struct irqaction **pp = p;
-			p = &action->next;
-			if (action->dev_id != dev_id)
-				continue;
-
-			/* Found it - now remove it from the list of entries */
-			*pp = action->next;
-			if (!desc->action) {
-				desc->status |= IRQ_DISABLED;
-				desc->handler->shutdown(irq);
-			}
-			spin_unlock_irqrestore(&desc->lock,flags);
-
-			synchronize_irq(irq);
-			kfree(action);
-			return;
-		}
-		printk("Trying to free free IRQ%d\n",irq);
-		spin_unlock_irqrestore(&desc->lock,flags);
-		return;
-	}
-}
-
-/*
- * IRQ autodetection code..
- *
- * This depends on the fact that any interrupt that
- * comes in on to an unassigned handler will get stuck
- * with "IRQ_WAITING" cleared and the interrupt
- * disabled.
- */
-
-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)
-{
-	unsigned int i;
-	irq_desc_t *desc;
-	unsigned long val;
-	unsigned long delay;
-
-	down(&probe_sem);
-	/* 
-	 * something may have generated an irq long ago and we want to
-	 * flush such a longstanding irq before considering it as spurious. 
-	 */
-	for (i = NR_IRQS-1; i > 0; i--)  {
-		desc = irq_desc + i;
-
-		spin_lock_irq(&desc->lock);
-		if (!irq_desc[i].action) 
-			irq_desc[i].handler->startup(i);
-		spin_unlock_irq(&desc->lock);
-	}
-
-	/* Wait for longstanding interrupts to trigger. */
-	for (delay = jiffies + HZ/50; time_after(delay, jiffies); )
-		/* about 20ms delay */ barrier();
-
-	/*
-	 * enable any unassigned irqs
-	 * (we must startup again here because if a longstanding irq
-	 * happened in the previous stage, it may have masked itself)
-	 */
-	for (i = NR_IRQS-1; i > 0; i--) {
-		desc = irq_desc + i;
-
-		spin_lock_irq(&desc->lock);
-		if (!desc->action) {
-			desc->status |= IRQ_AUTODETECT | IRQ_WAITING;
-			if (desc->handler->startup(i))
-				desc->status |= IRQ_PENDING;
-		}
-		spin_unlock_irq(&desc->lock);
-	}
-
-	/*
-	 * Wait for spurious interrupts to trigger
-	 */
-	for (delay = jiffies + HZ/10; time_after(delay, jiffies); )
-		/* about 100ms delay */ barrier();
-
-	/*
-	 * Now filter out any obviously spurious interrupts
-	 */
-	val = 0;
-	for (i = 0; i < NR_IRQS; i++) {
-		irq_desc_t *desc = irq_desc + i;
-		unsigned int status;
-
-		spin_lock_irq(&desc->lock);
-		status = desc->status;
-
-		if (status & IRQ_AUTODETECT) {
-			/* It triggered already - consider it spurious. */
-			if (!(status & IRQ_WAITING)) {
-				desc->status = status & ~IRQ_AUTODETECT;
-				desc->handler->shutdown(i);
-			} else
-				if (i < 32)
-					val |= 1 << i;
-		}
-		spin_unlock_irq(&desc->lock);
-	}
-
-	return val;
-}
-
-/*
- * 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 val)
-{
-	int i;
-	unsigned int mask;
-
-	mask = 0;
-	for (i = 0; i < NR_IRQS; i++) {
-		irq_desc_t *desc = irq_desc + i;
-		unsigned int status;
-
-		spin_lock_irq(&desc->lock);
-		status = desc->status;
-
-		if (status & IRQ_AUTODETECT) {
-			if (i < 16 && !(status & IRQ_WAITING))
-				mask |= 1 << i;
-
-			desc->status = status & ~IRQ_AUTODETECT;
-			desc->handler->shutdown(i);
-		}
-		spin_unlock_irq(&desc->lock);
-	}
-	up(&probe_sem);
-
-	return mask & val;
-}
-
-/*
- * Return the one interrupt that triggered (this can
- * handle any interrupt source).
- */
-
-/**
- *	probe_irq_off	- end an interrupt autodetect
- *	@val: 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 val)
-{
-	int i, irq_found, nr_irqs;
-
-	nr_irqs = 0;
-	irq_found = 0;
-	for (i = 0; i < NR_IRQS; i++) {
-		irq_desc_t *desc = irq_desc + i;
-		unsigned int status;
-
-		spin_lock_irq(&desc->lock);
-		status = desc->status;
-
-		if (status & IRQ_AUTODETECT) {
-			if (!(status & IRQ_WAITING)) {
-				if (!nr_irqs)
-					irq_found = i;
-				nr_irqs++;
-			}
-			desc->status = status & ~IRQ_AUTODETECT;
-			desc->handler->shutdown(i);
-		}
-		spin_unlock_irq(&desc->lock);
-	}
-	up(&probe_sem);
-
-	if (nr_irqs > 1)
-		irq_found = -irq_found;
-	return irq_found;
-}
-
-/* this was setup_x86_irq but it seems pretty generic */
-int setup_irq(unsigned int irq, struct irqaction * new)
-{
-	int shared = 0;
-	unsigned long flags;
-	struct irqaction *old, **p;
-	irq_desc_t *desc = irq_desc + irq;
-
-	/*
-	 * 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);
-	}
-
-	/*
-	 * The following block of code has to be executed atomically
-	 */
-	spin_lock_irqsave(&desc->lock,flags);
-	p = &desc->action;
-	if ((old = *p) != NULL) {
-		/* Can't share interrupts unless both agree to */
-		if (!(old->flags & new->flags & SA_SHIRQ)) {
-			spin_unlock_irqrestore(&desc->lock,flags);
-			return -EBUSY;
-		}
-
-		/* add new interrupt at end of irq queue */
-		do {
-			p = &old->next;
-			old = *p;
-		} while (old);
-		shared = 1;
-	}
-
-	*p = new;
-
-	if (!shared) {
-		desc->depth = 0;
-		desc->status &= ~(IRQ_DISABLED | IRQ_AUTODETECT | IRQ_WAITING | IRQ_INPROGRESS);
-		desc->handler->startup(irq);
-	}
-	spin_unlock_irqrestore(&desc->lock,flags);
-
-	/* register_irq_proc(irq); */
-	return 0;
 }
 
 /* Initialize irq handling for IRQs.
diff --minimal -urN -X /usr/share/dontdiff linux-2.5.64.vanilla/include/asm-v850/hw_irq.h linux-2.5.64/include/asm-v850/hw_irq.h
--- linux-2.5.64.vanilla/include/asm-v850/hw_irq.h	Thu Nov 28 01:36:18 2002
+++ linux-2.5.64/include/asm-v850/hw_irq.h	Tue Mar 11 10:39:02 2003
@@ -5,4 +5,23 @@
 {
 }
 
+#define arch_ack_bad_irq(irq) do { } while (0)
+
+/* Return a pointer to the irq descriptor for IRQ.  */
+#define irq_desc(irq) (irq_desc + (irq))
+
+/* Check irq number */
+#define irq_valid(irq) ((irq) < NR_IRQS)
+
+/* Arch specific hook for setup_irq() */
+#define arch_setup_irq(irq, desc, irqaction) do { } while (0)
+
+/* Used in setup_irq() */
+#define ARCH_NONSHARED_IRQ_MASK \
+	~(IRQ_DISABLED | IRQ_AUTODETECT | IRQ_WAITING | IRQ_INPROGRESS)
+
+#define HAVE_ARCH_IRQ_PROC
+
+#define register_irq_proc(irq) do { } while (0)
+
 #endif /* __V850_HW_IRQ_H__ */

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2003-03-14  4:02 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2003-01-21 10:45 [PATCH] irq handling code consolidation (common part) Andrey Panin
2003-01-21 10:51 ` [PATCH] irq handling code consolidation (i386 part) Andrey Panin
2003-01-21 10:57 ` [PATCH] irq handling code consolidation (alpha part) Andrey Panin
2003-01-21 10:59 ` [PATCH] irq handling code consolidation (ppc part) Andrey Panin
2003-01-21 11:05 ` [PATCH] irq handling code consolidation (v850 part) Andrey Panin
2003-01-22  6:04   ` Miles Bader
2003-01-21 11:07 ` [PATCH] irq handling code consolidation (x8_64 part) Andrey Panin
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2003-03-13 13:29 [PATCH] irq handling code consolidation (v850 part) Andrey Panin
2003-03-14  4:13 ` Miles Bader

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