pic.c

linux内核源码

		max_irqs = max_real_irqs = 32;
		level_mask[0] = OHARE_LEVEL_MASK;

		/* We might have a second cascaded ohare */
		slave = of_find_node_by_name(NULL, "pci106b,7");
		if (slave) {
			max_irqs = 64;
			level_mask[1] = OHARE_LEVEL_MASK;
		}
	} else if ((master = of_find_node_by_name(NULL, "mac-io")) != NULL) {
		max_irqs = max_real_irqs = 64;
		level_mask[0] = HEATHROW_LEVEL_MASK;
		level_mask[1] = 0;

		/* We might have a second cascaded heathrow */
		slave = of_find_node_by_name(master, "mac-io");

		/* Check ordering of master & slave */
		if (of_device_is_compatible(master, "gatwick")) {
			struct device_node *tmp;
			BUG_ON(slave == NULL);
			tmp = master;
			master = slave;
			slave = tmp;
		}

		/* We found a slave */
		if (slave) {
			max_irqs = 128;
			level_mask[2] = HEATHROW_LEVEL_MASK;
			level_mask[3] = 0;
		}
	}
	BUG_ON(master == NULL);

	/*
	 * Allocate an irq host
	 */
	pmac_pic_host = irq_alloc_host(master, IRQ_HOST_MAP_LINEAR, max_irqs,
				       &pmac_pic_host_ops,
				       max_irqs);
	BUG_ON(pmac_pic_host == NULL);
	irq_set_default_host(pmac_pic_host);

	/* Get addresses of first controller if we have a node for it */
	BUG_ON(of_address_to_resource(master, 0, &r));

	/* Map interrupts of primary controller */
	addr = (u8 __iomem *) ioremap(r.start, 0x40);
	i = 0;
	pmac_irq_hw[i++] = (volatile struct pmac_irq_hw __iomem *)
		(addr + 0x20);
	if (max_real_irqs > 32)
		pmac_irq_hw[i++] = (volatile struct pmac_irq_hw __iomem *)
			(addr + 0x10);
	of_node_put(master);

	printk(KERN_INFO "irq: Found primary Apple PIC %s for %d irqs\n",
	       master->full_name, max_real_irqs);

	/* Map interrupts of cascaded controller */
	if (slave && !of_address_to_resource(slave, 0, &r)) {
		addr = (u8 __iomem *)ioremap(r.start, 0x40);
		pmac_irq_hw[i++] = (volatile struct pmac_irq_hw __iomem *)
			(addr + 0x20);
		if (max_irqs > 64)
			pmac_irq_hw[i++] =
				(volatile struct pmac_irq_hw __iomem *)
				(addr + 0x10);
		pmac_irq_cascade = irq_of_parse_and_map(slave, 0);

		printk(KERN_INFO "irq: Found slave Apple PIC %s for %d irqs"
		       " cascade: %d\n", slave->full_name,
		       max_irqs - max_real_irqs, pmac_irq_cascade);
	}
	of_node_put(slave);

	/* Disable all interrupts in all controllers */
	for (i = 0; i * 32 < max_irqs; ++i)
		out_le32(&pmac_irq_hw[i]->enable, 0);

	/* Hookup cascade irq */
	if (slave && pmac_irq_cascade != NO_IRQ)
		setup_irq(pmac_irq_cascade, &gatwick_cascade_action);

	printk(KERN_INFO "irq: System has %d possible interrupts\n", max_irqs);
#ifdef CONFIG_XMON
	setup_irq(irq_create_mapping(NULL, 20), &xmon_action);
#endif
}
#endif /* CONFIG_PPC32 */

static void pmac_u3_cascade(unsigned int irq, struct irq_desc *desc)
{
	struct mpic *mpic = desc->handler_data;

	unsigned int cascade_irq = mpic_get_one_irq(mpic);
	if (cascade_irq != NO_IRQ)
		generic_handle_irq(cascade_irq);
	desc->chip->eoi(irq);
}

static void __init pmac_pic_setup_mpic_nmi(struct mpic *mpic)
{
#if defined(CONFIG_XMON) && defined(CONFIG_PPC32)
	struct device_node* pswitch;
	int nmi_irq;

	pswitch = of_find_node_by_name(NULL, "programmer-switch");
	if (pswitch) {
		nmi_irq = irq_of_parse_and_map(pswitch, 0);
		if (nmi_irq != NO_IRQ) {
			mpic_irq_set_priority(nmi_irq, 9);
			setup_irq(nmi_irq, &xmon_action);
		}
		of_node_put(pswitch);
	}
#endif	/* defined(CONFIG_XMON) && defined(CONFIG_PPC32) */
}

static struct mpic * __init pmac_setup_one_mpic(struct device_node *np,
						int master)
{
	const char *name = master ? " MPIC 1   " : " MPIC 2   ";
	struct resource r;
	struct mpic *mpic;
	unsigned int flags = master ? MPIC_PRIMARY : 0;
	int rc;

	rc = of_address_to_resource(np, 0, &r);
	if (rc)
		return NULL;

	pmac_call_feature(PMAC_FTR_ENABLE_MPIC, np, 0, 0);

	flags |= MPIC_WANTS_RESET;
	if (of_get_property(np, "big-endian", NULL))
		flags |= MPIC_BIG_ENDIAN;

	/* Primary Big Endian means HT interrupts. This is quite dodgy
	 * but works until I find a better way
	 */
	if (master && (flags & MPIC_BIG_ENDIAN))
		flags |= MPIC_U3_HT_IRQS;

	mpic = mpic_alloc(np, r.start, flags, 0, 0, name);
	if (mpic == NULL)
		return NULL;

	mpic_init(mpic);

	return mpic;
 }

static int __init pmac_pic_probe_mpic(void)
{
	struct mpic *mpic1, *mpic2;
	struct device_node *np, *master = NULL, *slave = NULL;
	unsigned int cascade;

	/* We can have up to 2 MPICs cascaded */
	for (np = NULL; (np = of_find_node_by_type(np, "open-pic"))
		     != NULL;) {
		if (master == NULL &&
		    of_get_property(np, "interrupts", NULL) == NULL)
			master = of_node_get(np);
		else if (slave == NULL)
			slave = of_node_get(np);
		if (master && slave)
			break;
	}

	/* Check for bogus setups */
	if (master == NULL && slave != NULL) {
		master = slave;
		slave = NULL;
	}

	/* Not found, default to good old pmac pic */
	if (master == NULL)
		return -ENODEV;

	/* Set master handler */
	ppc_md.get_irq = mpic_get_irq;

	/* Setup master */
	mpic1 = pmac_setup_one_mpic(master, 1);
	BUG_ON(mpic1 == NULL);

	/* Install NMI if any */
	pmac_pic_setup_mpic_nmi(mpic1);

	of_node_put(master);

	/* No slave, let's go out */
	if (slave == NULL)
		return 0;

	/* Get/Map slave interrupt */
	cascade = irq_of_parse_and_map(slave, 0);
	if (cascade == NO_IRQ) {
		printk(KERN_ERR "Failed to map cascade IRQ\n");
		return 0;
	}

	mpic2 = pmac_setup_one_mpic(slave, 0);
	if (mpic2 == NULL) {
		printk(KERN_ERR "Failed to setup slave MPIC\n");
		of_node_put(slave);
		return 0;
	}
	set_irq_data(cascade, mpic2);
	set_irq_chained_handler(cascade, pmac_u3_cascade);

	of_node_put(slave);
	return 0;
}


void __init pmac_pic_init(void)
{
	unsigned int flags = 0;

	/* We configure the OF parsing based on our oldworld vs. newworld
	 * platform type and wether we were booted by BootX.
	 */
#ifdef CONFIG_PPC32
	if (!pmac_newworld)
		flags |= OF_IMAP_OLDWORLD_MAC;
	if (of_get_property(of_chosen, "linux,bootx", NULL) != NULL)
		flags |= OF_IMAP_NO_PHANDLE;
#endif /* CONFIG_PPC_32 */

	of_irq_map_init(flags);

	/* We first try to detect Apple's new Core99 chipset, since mac-io
	 * is quite different on those machines and contains an IBM MPIC2.
	 */
	if (pmac_pic_probe_mpic() == 0)
		return;

#ifdef CONFIG_PPC32
	pmac_pic_probe_oldstyle();
#endif
}

#if defined(CONFIG_PM) && defined(CONFIG_PPC32)
/*
 * These procedures are used in implementing sleep on the powerbooks.
 * sleep_save_intrs() saves the states of all interrupt enables
 * and disables all interrupts except for the nominated one.
 * sleep_restore_intrs() restores the states of all interrupt enables.
 */
unsigned long sleep_save_mask[2];

/* This used to be passed by the PMU driver but that link got
 * broken with the new driver model. We use this tweak for now...
 * We really want to do things differently though...
 */
static int pmacpic_find_viaint(void)
{
	int viaint = -1;

#ifdef CONFIG_ADB_PMU
	struct device_node *np;

	if (pmu_get_model() != PMU_OHARE_BASED)
		goto not_found;
	np = of_find_node_by_name(NULL, "via-pmu");
	if (np == NULL)
		goto not_found;
	viaint = irq_of_parse_and_map(np, 0);;
#endif /* CONFIG_ADB_PMU */

not_found:
	return viaint;
}

static int pmacpic_suspend(struct sys_device *sysdev, pm_message_t state)
{
	int viaint = pmacpic_find_viaint();

	sleep_save_mask[0] = ppc_cached_irq_mask[0];
	sleep_save_mask[1] = ppc_cached_irq_mask[1];
	ppc_cached_irq_mask[0] = 0;
	ppc_cached_irq_mask[1] = 0;
	if (viaint > 0)
		set_bit(viaint, ppc_cached_irq_mask);
	out_le32(&pmac_irq_hw[0]->enable, ppc_cached_irq_mask[0]);
	if (max_real_irqs > 32)
		out_le32(&pmac_irq_hw[1]->enable, ppc_cached_irq_mask[1]);
	(void)in_le32(&pmac_irq_hw[0]->event);
	/* make sure mask gets to controller before we return to caller */
	mb();
        (void)in_le32(&pmac_irq_hw[0]->enable);

        return 0;
}

static int pmacpic_resume(struct sys_device *sysdev)
{
	int i;

	out_le32(&pmac_irq_hw[0]->enable, 0);
	if (max_real_irqs > 32)
		out_le32(&pmac_irq_hw[1]->enable, 0);
	mb();
	for (i = 0; i < max_real_irqs; ++i)
		if (test_bit(i, sleep_save_mask))
			pmac_unmask_irq(i);

	return 0;
}

#endif /* CONFIG_PM && CONFIG_PPC32 */

static struct sysdev_class pmacpic_sysclass = {
	set_kset_name("pmac_pic"),
};

static struct sys_device device_pmacpic = {
	.id		= 0,
	.cls		= &pmacpic_sysclass,
};

static struct sysdev_driver driver_pmacpic = {
#if defined(CONFIG_PM) && defined(CONFIG_PPC32)
	.suspend	= &pmacpic_suspend,
	.resume		= &pmacpic_resume,
#endif /* CONFIG_PM && CONFIG_PPC32 */
};

static int __init init_pmacpic_sysfs(void)
{
#ifdef CONFIG_PPC32
	if (max_irqs == 0)
		return -ENODEV;
#endif
	printk(KERN_DEBUG "Registering pmac pic with sysfs...\n");
	sysdev_class_register(&pmacpic_sysclass);
	sysdev_register(&device_pmacpic);
	sysdev_driver_register(&pmacpic_sysclass, &driver_pmacpic);
	return 0;
}

subsys_initcall(init_pmacpic_sysfs);