[linux-2.6-block.git] / arch / powerpc / sysdev / xics / xics-common.c

/*
 * Copyright 2011 IBM Corporation.
 *
 *  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.
 *
 */
#include <linux/types.h>
#include <linux/threads.h>
#include <linux/kernel.h>
#include <linux/irq.h>
#include <linux/debugfs.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/spinlock.h>

#include <asm/prom.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/machdep.h>
#include <asm/irq.h>
#include <asm/errno.h>
#include <asm/rtas.h>
#include <asm/xics.h>
#include <asm/firmware.h>

/* Globals common to all ICP/ICS implementations */
const struct icp_ops	*icp_ops;

unsigned int xics_default_server		= 0xff;
unsigned int xics_default_distrib_server	= 0;
unsigned int xics_interrupt_server_size		= 8;

DEFINE_PER_CPU(struct xics_cppr, xics_cppr);

struct irq_host *xics_host;

static LIST_HEAD(ics_list);

void xics_update_irq_servers(void)
{
	int i, j;
	struct device_node *np;
	u32 ilen;
	const u32 *ireg;
	u32 hcpuid;

	/* Find the server numbers for the boot cpu. */
	np = of_get_cpu_node(boot_cpuid, NULL);
	BUG_ON(!np);

	hcpuid = get_hard_smp_processor_id(boot_cpuid);
	xics_default_server = xics_default_distrib_server = hcpuid;

	pr_devel("xics: xics_default_server = 0x%x\n", xics_default_server);

	ireg = of_get_property(np, "ibm,ppc-interrupt-gserver#s", &ilen);
	if (!ireg) {
		of_node_put(np);
		return;
	}

	i = ilen / sizeof(int);

	/* Global interrupt distribution server is specified in the last
	 * entry of "ibm,ppc-interrupt-gserver#s" property. Get the last
	 * entry fom this property for current boot cpu id and use it as
	 * default distribution server
	 */
	for (j = 0; j < i; j += 2) {
		if (ireg[j] == hcpuid) {
			xics_default_distrib_server = ireg[j+1];
			break;
		}
	}
	pr_devel("xics: xics_default_distrib_server = 0x%x\n",
		 xics_default_distrib_server);
	of_node_put(np);
}

/* GIQ stuff, currently only supported on RTAS setups, will have
 * to be sorted properly for bare metal
 */
void xics_set_cpu_giq(unsigned int gserver, unsigned int join)
{
#ifdef CONFIG_PPC_RTAS
	int index;
	int status;

	if (!rtas_indicator_present(GLOBAL_INTERRUPT_QUEUE, NULL))
		return;

	index = (1UL << xics_interrupt_server_size) - 1 - gserver;

	status = rtas_set_indicator_fast(GLOBAL_INTERRUPT_QUEUE, index, join);

	WARN(status < 0, "set-indicator(%d, %d, %u) returned %d\n",
	     GLOBAL_INTERRUPT_QUEUE, index, join, status);
#endif
}

void xics_setup_cpu(void)
{
	icp_ops->set_priority(LOWEST_PRIORITY);

	xics_set_cpu_giq(xics_default_distrib_server, 1);
}

void xics_mask_unknown_vec(unsigned int vec)
{
	struct ics *ics;

	pr_err("Interrupt 0x%x (real) is invalid, disabling it.\n", vec);

	list_for_each_entry(ics, &ics_list, link)
		ics->mask_unknown(ics, vec);
}


#ifdef CONFIG_SMP

static void xics_request_ipi(void)
{
	unsigned int ipi;

	ipi = irq_create_mapping(xics_host, XICS_IPI);
	BUG_ON(ipi == NO_IRQ);

	/*
	 * IPIs are marked IRQF_DISABLED as they must run with irqs
	 * disabled
	 */
	irq_set_handler(ipi, handle_percpu_irq);
	BUG_ON(request_irq(ipi, icp_ops->ipi_action,
			   IRQF_DISABLED|IRQF_PERCPU, "IPI", NULL));
}

int __init xics_smp_probe(void)
{
	/* Setup cause_ipi callback  based on which ICP is used */
	smp_ops->cause_ipi = icp_ops->cause_ipi;

	/* Register all the IPIs */
	xics_request_ipi();

	return cpumask_weight(cpu_possible_mask);
}

#endif /* CONFIG_SMP */

void xics_teardown_cpu(void)
{
	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);

	/*
	 * we have to reset the cppr index to 0 because we're
	 * not going to return from the IPI
	 */
	os_cppr->index = 0;
	icp_ops->set_priority(0);
	icp_ops->teardown_cpu();
}

void xics_kexec_teardown_cpu(int secondary)
{
	xics_teardown_cpu();

	icp_ops->flush_ipi();

	/*
	 * Some machines need to have at least one cpu in the GIQ,
	 * so leave the master cpu in the group.
	 */
	if (secondary)
		xics_set_cpu_giq(xics_default_distrib_server, 0);
}


#ifdef CONFIG_HOTPLUG_CPU

/* Interrupts are disabled. */
void xics_migrate_irqs_away(void)
{
	int cpu = smp_processor_id(), hw_cpu = hard_smp_processor_id();
	unsigned int irq, virq;

	/* If we used to be the default server, move to the new "boot_cpuid" */
	if (hw_cpu == xics_default_server)
		xics_update_irq_servers();

	/* Reject any interrupt that was queued to us... */
	icp_ops->set_priority(0);

	/* Remove ourselves from the global interrupt queue */
	xics_set_cpu_giq(xics_default_distrib_server, 0);

	/* Allow IPIs again... */
	icp_ops->set_priority(DEFAULT_PRIORITY);

	for_each_irq(virq) {
		struct irq_desc *desc;
		struct irq_chip *chip;
		long server;
		unsigned long flags;
		struct ics *ics;

		/* We can't set affinity on ISA interrupts */
		if (virq < NUM_ISA_INTERRUPTS)
			continue;
		if (virq_to_host(virq) != xics_host)
			continue;
		irq = (unsigned int)virq_to_hw(virq);
		/* We need to get IPIs still. */
		if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
			continue;
		desc = irq_to_desc(virq);
		/* We only need to migrate enabled IRQS */
		if (!desc || !desc->action)
			continue;
		chip = irq_desc_get_chip(desc);
		if (!chip || !chip->irq_set_affinity)
			continue;

		raw_spin_lock_irqsave(&desc->lock, flags);

		/* Locate interrupt server */
		server = -1;
		ics = irq_get_chip_data(virq);
		if (ics)
			server = ics->get_server(ics, irq);
		if (server < 0) {
			printk(KERN_ERR "%s: Can't find server for irq %d\n",
			       __func__, irq);
			goto unlock;
		}

		/* We only support delivery to all cpus or to one cpu.
		 * The irq has to be migrated only in the single cpu
		 * case.
		 */
		if (server != hw_cpu)
			goto unlock;

		/* This is expected during cpu offline. */
		if (cpu_online(cpu))
			pr_warning("IRQ %u affinity broken off cpu %u\n",
			       virq, cpu);

		/* Reset affinity to all cpus */
		raw_spin_unlock_irqrestore(&desc->lock, flags);
		irq_set_affinity(virq, cpu_all_mask);
		continue;
unlock:
		raw_spin_unlock_irqrestore(&desc->lock, flags);
	}
}
#endif /* CONFIG_HOTPLUG_CPU */

#ifdef CONFIG_SMP
/*
 * For the moment we only implement delivery to all cpus or one cpu.
 *
 * If the requested affinity is cpu_all_mask, we set global affinity.
 * If not we set it to the first cpu in the mask, even if multiple cpus
 * are set. This is so things like irqbalance (which set core and package
 * wide affinities) do the right thing.
 *
 * We need to fix this to implement support for the links
 */
int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
			unsigned int strict_check)
{

	if (!distribute_irqs)
		return xics_default_server;

	if (!cpumask_subset(cpu_possible_mask, cpumask)) {
		int server = cpumask_first_and(cpu_online_mask, cpumask);

		if (server < nr_cpu_ids)
			return get_hard_smp_processor_id(server);

		if (strict_check)
			return -1;
	}

	/*
	 * Workaround issue with some versions of JS20 firmware that
	 * deliver interrupts to cpus which haven't been started. This
	 * happens when using the maxcpus= boot option.
	 */
	if (cpumask_equal(cpu_online_mask, cpu_present_mask))
		return xics_default_distrib_server;

	return xics_default_server;
}
#endif /* CONFIG_SMP */

static int xics_host_match(struct irq_host *h, struct device_node *node)
{
	struct ics *ics;

	list_for_each_entry(ics, &ics_list, link)
		if (ics->host_match(ics, node))
			return 1;

	return 0;
}

/* Dummies */
static void xics_ipi_unmask(struct irq_data *d) { }
static void xics_ipi_mask(struct irq_data *d) { }

static struct irq_chip xics_ipi_chip = {
	.name = "XICS",
	.irq_eoi = NULL, /* Patched at init time */
	.irq_mask = xics_ipi_mask,
	.irq_unmask = xics_ipi_unmask,
};

static int xics_host_map(struct irq_host *h, unsigned int virq,
			 irq_hw_number_t hw)
{
	struct ics *ics;

	pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hw);

	/* Insert the interrupt mapping into the radix tree for fast lookup */
	irq_radix_revmap_insert(xics_host, virq, hw);

	/* They aren't all level sensitive but we just don't really know */
	irq_set_status_flags(virq, IRQ_LEVEL);

	/* Don't call into ICS for IPIs */
	if (hw == XICS_IPI) {
		irq_set_chip_and_handler(virq, &xics_ipi_chip,
					 handle_fasteoi_irq);
		return 0;
	}

	/* Let the ICS setup the chip data */
	list_for_each_entry(ics, &ics_list, link)
		if (ics->map(ics, virq) == 0)
			break;
	return 0;
}

static int xics_host_xlate(struct irq_host *h, struct device_node *ct,
			   const u32 *intspec, unsigned int intsize,
			   irq_hw_number_t *out_hwirq, unsigned int *out_flags)

{
	/* Current xics implementation translates everything
	 * to level. It is not technically right for MSIs but this
	 * is irrelevant at this point. We might get smarter in the future
	 */
	*out_hwirq = intspec[0];
	*out_flags = IRQ_TYPE_LEVEL_LOW;

	return 0;
}

static struct irq_host_ops xics_host_ops = {
	.match = xics_host_match,
	.map = xics_host_map,
	.xlate = xics_host_xlate,
};

static void __init xics_init_host(void)
{
	xics_host = irq_alloc_host(NULL, IRQ_HOST_MAP_TREE, 0, &xics_host_ops,
				   XICS_IRQ_SPURIOUS);
	BUG_ON(xics_host == NULL);
	irq_set_default_host(xics_host);
}

void __init xics_register_ics(struct ics *ics)
{
	list_add(&ics->link, &ics_list);
}

static void __init xics_get_server_size(void)
{
	struct device_node *np;
	const u32 *isize;

	/* We fetch the interrupt server size from the first ICS node
	 * we find if any
	 */
	np = of_find_compatible_node(NULL, NULL, "ibm,ppc-xics");
	if (!np)
		return;
	isize = of_get_property(np, "ibm,interrupt-server#-size", NULL);
	if (!isize)
		return;
	xics_interrupt_server_size = *isize;
	of_node_put(np);
}

void __init xics_init(void)
{
	int rc = -1;

	/* Fist locate ICP */
#ifdef CONFIG_PPC_ICP_HV
	if (firmware_has_feature(FW_FEATURE_LPAR))
		rc = icp_hv_init();
#endif
#ifdef CONFIG_PPC_ICP_NATIVE
	if (rc < 0)
		rc = icp_native_init();
#endif
	if (rc < 0) {
		pr_warning("XICS: Cannot find a Presentation Controller !\n");
		return;
	}

	/* Copy get_irq callback over to ppc_md */
	ppc_md.get_irq = icp_ops->get_irq;

	/* Patch up IPI chip EOI */
	xics_ipi_chip.irq_eoi = icp_ops->eoi;

	/* Now locate ICS */
#ifdef CONFIG_PPC_ICS_RTAS
	rc = ics_rtas_init();
#endif
	if (rc < 0)
		pr_warning("XICS: Cannot find a Source Controller !\n");

	/* Initialize common bits */
	xics_get_server_size();
	xics_update_irq_servers();
	xics_init_host();
	xics_setup_cpu();
}
Commit	Line	Data
0b05ac6e BH	1	/*
	2	* Copyright 2011 IBM Corporation.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation; either version
	7	* 2 of the License, or (at your option) any later version.
	8	*
	9	*/
	10	#include <linux/types.h>
	11	#include <linux/threads.h>
	12	#include <linux/kernel.h>
	13	#include <linux/irq.h>
	14	#include <linux/debugfs.h>
	15	#include <linux/smp.h>
	16	#include <linux/interrupt.h>
	17	#include <linux/seq_file.h>
	18	#include <linux/init.h>
	19	#include <linux/cpu.h>
	20	#include <linux/of.h>
	21	#include <linux/slab.h>
	22	#include <linux/spinlock.h>
	23
	24	#include <asm/prom.h>
	25	#include <asm/io.h>
	26	#include <asm/smp.h>
	27	#include <asm/machdep.h>
	28	#include <asm/irq.h>
	29	#include <asm/errno.h>
	30	#include <asm/rtas.h>
	31	#include <asm/xics.h>
	32	#include <asm/firmware.h>
	33
	34	/* Globals common to all ICP/ICS implementations */
	35	const struct icp_ops *icp_ops;
	36
	37	unsigned int xics_default_server = 0xff;
	38	unsigned int xics_default_distrib_server = 0;
	39	unsigned int xics_interrupt_server_size = 8;
	40
	41	DEFINE_PER_CPU(struct xics_cppr, xics_cppr);
	42
	43	struct irq_host *xics_host;
	44
	45	static LIST_HEAD(ics_list);
	46
	47	void xics_update_irq_servers(void)
	48	{
	49	int i, j;
	50	struct device_node *np;
	51	u32 ilen;
	52	const u32 *ireg;
	53	u32 hcpuid;
	54
	55	/* Find the server numbers for the boot cpu. */
	56	np = of_get_cpu_node(boot_cpuid, NULL);
	57	BUG_ON(!np);
	58
	59	hcpuid = get_hard_smp_processor_id(boot_cpuid);
f6e17f9b BH	60	xics_default_server = xics_default_distrib_server = hcpuid;
	61
	62	pr_devel("xics: xics_default_server = 0x%x\n", xics_default_server);
0b05ac6e BH	63
	64	ireg = of_get_property(np, "ibm,ppc-interrupt-gserver#s", &ilen);
	65	if (!ireg) {
	66	of_node_put(np);
	67	return;
	68	}
	69
	70	i = ilen / sizeof(int);
	71
	72	/* Global interrupt distribution server is specified in the last
	73	* entry of "ibm,ppc-interrupt-gserver#s" property. Get the last
	74	* entry fom this property for current boot cpu id and use it as
	75	* default distribution server
	76	*/
	77	for (j = 0; j < i; j += 2) {
	78	if (ireg[j] == hcpuid) {
	79	xics_default_distrib_server = ireg[j+1];
f6e17f9b	80	break;
0b05ac6e BH	81	}
0b05ac6e BH	82	}
f6e17f9b BH	83	pr_devel("xics: xics_default_distrib_server = 0x%x\n",
f6e17f9b BH	84	xics_default_distrib_server);
0b05ac6e BH	85	of_node_put(np);
	86	}
	87
	88	/* GIQ stuff, currently only supported on RTAS setups, will have
	89	* to be sorted properly for bare metal
	90	*/
	91	void xics_set_cpu_giq(unsigned int gserver, unsigned int join)
	92	{
	93	#ifdef CONFIG_PPC_RTAS
	94	int index;
	95	int status;
	96
	97	if (!rtas_indicator_present(GLOBAL_INTERRUPT_QUEUE, NULL))
	98	return;
	99
	100	index = (1UL << xics_interrupt_server_size) - 1 - gserver;
	101
	102	status = rtas_set_indicator_fast(GLOBAL_INTERRUPT_QUEUE, index, join);
	103
	104	WARN(status < 0, "set-indicator(%d, %d, %u) returned %d\n",
	105	GLOBAL_INTERRUPT_QUEUE, index, join, status);
	106	#endif
	107	}
	108
	109	void xics_setup_cpu(void)
	110	{
	111	icp_ops->set_priority(LOWEST_PRIORITY);
	112
	113	xics_set_cpu_giq(xics_default_distrib_server, 1);
	114	}
	115
	116	void xics_mask_unknown_vec(unsigned int vec)
	117	{
	118	struct ics *ics;
	119
f6e17f9b	120	pr_err("Interrupt 0x%x (real) is invalid, disabling it.\n", vec);
0b05ac6e BH	121
	122	list_for_each_entry(ics, &ics_list, link)
	123	ics->mask_unknown(ics, vec);
	124	}
	125
	126
	127	#ifdef CONFIG_SMP
	128
0b05ac6e BH	129	static void xics_request_ipi(void)
	130	{
	131	unsigned int ipi;
	132
	133	ipi = irq_create_mapping(xics_host, XICS_IPI);
	134	BUG_ON(ipi == NO_IRQ);
	135
	136	/*
	137	* IPIs are marked IRQF_DISABLED as they must run with irqs
	138	* disabled
	139	*/
	140	irq_set_handler(ipi, handle_percpu_irq);
	141	BUG_ON(request_irq(ipi, icp_ops->ipi_action,
	142	IRQF_DISABLED\|IRQF_PERCPU, "IPI", NULL));
	143	}
	144
	145	int __init xics_smp_probe(void)
	146	{
23d72bfd MM	147	/* Setup cause_ipi callback based on which ICP is used */
23d72bfd MM	148	smp_ops->cause_ipi = icp_ops->cause_ipi;
0b05ac6e BH	149
	150	/* Register all the IPIs */
	151	xics_request_ipi();
	152
	153	return cpumask_weight(cpu_possible_mask);
	154	}
	155
	156	#endif /* CONFIG_SMP */
	157
	158	void xics_teardown_cpu(void)
	159	{
	160	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
	161
	162	/*
	163	* we have to reset the cppr index to 0 because we're
	164	* not going to return from the IPI
	165	*/
	166	os_cppr->index = 0;
	167	icp_ops->set_priority(0);
	168	icp_ops->teardown_cpu();
	169	}
	170
	171	void xics_kexec_teardown_cpu(int secondary)
	172	{
	173	xics_teardown_cpu();
	174
	175	icp_ops->flush_ipi();
	176
	177	/*
	178	* Some machines need to have at least one cpu in the GIQ,
	179	* so leave the master cpu in the group.
	180	*/
	181	if (secondary)
	182	xics_set_cpu_giq(xics_default_distrib_server, 0);
	183	}
	184
	185
	186	#ifdef CONFIG_HOTPLUG_CPU
	187
	188	/* Interrupts are disabled. */
	189	void xics_migrate_irqs_away(void)
	190	{
	191	int cpu = smp_processor_id(), hw_cpu = hard_smp_processor_id();
	192	unsigned int irq, virq;
	193
	194	/* If we used to be the default server, move to the new "boot_cpuid" */
	195	if (hw_cpu == xics_default_server)
	196	xics_update_irq_servers();
	197
	198	/* Reject any interrupt that was queued to us... */
	199	icp_ops->set_priority(0);
	200
	201	/* Remove ourselves from the global interrupt queue */
	202	xics_set_cpu_giq(xics_default_distrib_server, 0);
	203
	204	/* Allow IPIs again... */
	205	icp_ops->set_priority(DEFAULT_PRIORITY);
	206
	207	for_each_irq(virq) {
	208	struct irq_desc *desc;
	209	struct irq_chip *chip;
	210	long server;
	211	unsigned long flags;
	212	struct ics *ics;
213
214	/* We can't set affinity on ISA interrupts */
215	if (virq < NUM_ISA_INTERRUPTS)
216	continue;
476eb491	217	if (virq_to_host(virq) != xics_host)
0b05ac6e	218	continue;
476eb491	219	irq = (unsigned int)virq_to_hw(virq);
0b05ac6e BH	220	/* We need to get IPIs still. */
	221	if (irq == XICS_IPI \|\| irq == XICS_IRQ_SPURIOUS)
	222	continue;
	223	desc = irq_to_desc(virq);
	224	/* We only need to migrate enabled IRQS */
	225	if (!desc \|\| !desc->action)
	226	continue;
	227	chip = irq_desc_get_chip(desc);
	228	if (!chip \|\| !chip->irq_set_affinity)
	229	continue;
	230
	231	raw_spin_lock_irqsave(&desc->lock, flags);
	232
	233	/* Locate interrupt server */
	234	server = -1;
	235	ics = irq_get_chip_data(virq);
	236	if (ics)
	237	server = ics->get_server(ics, irq);
	238	if (server < 0) {
	239	printk(KERN_ERR "%s: Can't find server for irq %d\n",
	240	__func__, irq);
	241	goto unlock;
	242	}
	243
	244	/* We only support delivery to all cpus or to one cpu.
	245	* The irq has to be migrated only in the single cpu
	246	* case.
	247	*/
	248	if (server != hw_cpu)
	249	goto unlock;
	250
	251	/* This is expected during cpu offline. */
	252	if (cpu_online(cpu))
	253	pr_warning("IRQ %u affinity broken off cpu %u\n",
	254	virq, cpu);
	255
	256	/* Reset affinity to all cpus */
	257	raw_spin_unlock_irqrestore(&desc->lock, flags);
	258	irq_set_affinity(virq, cpu_all_mask);
	259	continue;
	260	unlock:
	261	raw_spin_unlock_irqrestore(&desc->lock, flags);
	262	}
	263	}
	264	#endif /* CONFIG_HOTPLUG_CPU */
	265
	266	#ifdef CONFIG_SMP
	267	/*
	268	* For the moment we only implement delivery to all cpus or one cpu.
	269	*
	270	* If the requested affinity is cpu_all_mask, we set global affinity.
	271	* If not we set it to the first cpu in the mask, even if multiple cpus
	272	* are set. This is so things like irqbalance (which set core and package
	273	* wide affinities) do the right thing.
f6e17f9b BH	274	*
f6e17f9b BH	275	* We need to fix this to implement support for the links
0b05ac6e BH	276	*/
	277	int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
	278	unsigned int strict_check)
	279	{
	280
	281	if (!distribute_irqs)
	282	return xics_default_server;
	283
	284	if (!cpumask_subset(cpu_possible_mask, cpumask)) {
	285	int server = cpumask_first_and(cpu_online_mask, cpumask);
	286
	287	if (server < nr_cpu_ids)
	288	return get_hard_smp_processor_id(server);
	289
	290	if (strict_check)
	291	return -1;
	292	}
	293
	294	/*
	295	* Workaround issue with some versions of JS20 firmware that
	296	* deliver interrupts to cpus which haven't been started. This
	297	* happens when using the maxcpus= boot option.
	298	*/
	299	if (cpumask_equal(cpu_online_mask, cpu_present_mask))
	300	return xics_default_distrib_server;
	301
	302	return xics_default_server;
	303	}
	304	#endif /* CONFIG_SMP */
	305
	306	static int xics_host_match(struct irq_host h, struct device_node node)
	307	{
5ca12376 ME	308	struct ics *ics;
	309
	310	list_for_each_entry(ics, &ics_list, link)
	311	if (ics->host_match(ics, node))
	312	return 1;
	313
	314	return 0;
0b05ac6e BH	315	}
	316
	317	/* Dummies */
	318	static void xics_ipi_unmask(struct irq_data *d) { }
	319	static void xics_ipi_mask(struct irq_data *d) { }
	320
	321	static struct irq_chip xics_ipi_chip = {
	322	.name = "XICS",
	323	.irq_eoi = NULL, /* Patched at init time */
	324	.irq_mask = xics_ipi_mask,
	325	.irq_unmask = xics_ipi_unmask,
	326	};
	327
	328	static int xics_host_map(struct irq_host *h, unsigned int virq,
	329	irq_hw_number_t hw)
	330	{
	331	struct ics *ics;
	332
	333	pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hw);
	334
	335	/* Insert the interrupt mapping into the radix tree for fast lookup */
	336	irq_radix_revmap_insert(xics_host, virq, hw);
	337
	338	/* They aren't all level sensitive but we just don't really know */
	339	irq_set_status_flags(virq, IRQ_LEVEL);
	340
	341	/* Don't call into ICS for IPIs */
	342	if (hw == XICS_IPI) {
	343	irq_set_chip_and_handler(virq, &xics_ipi_chip,
	344	handle_fasteoi_irq);
	345	return 0;
	346	}
	347
	348	/* Let the ICS setup the chip data */
	349	list_for_each_entry(ics, &ics_list, link)
	350	if (ics->map(ics, virq) == 0)
	351	break;
	352	return 0;
	353	}
	354
	355	static int xics_host_xlate(struct irq_host h, struct device_node ct,
	356	const u32 *intspec, unsigned int intsize,
	357	irq_hw_number_t out_hwirq, unsigned int out_flags)
	358
	359	{
	360	/* Current xics implementation translates everything
	361	* to level. It is not technically right for MSIs but this
	362	* is irrelevant at this point. We might get smarter in the future
	363	*/
	364	*out_hwirq = intspec[0];
	365	*out_flags = IRQ_TYPE_LEVEL_LOW;
	366
	367	return 0;
	368	}
	369
	370	static struct irq_host_ops xics_host_ops = {
	371	.match = xics_host_match,
	372	.map = xics_host_map,
	373	.xlate = xics_host_xlate,
	374	};
	375
	376	static void __init xics_init_host(void)
	377	{
	378	xics_host = irq_alloc_host(NULL, IRQ_HOST_MAP_TREE, 0, &xics_host_ops,
379	XICS_IRQ_SPURIOUS);
380	BUG_ON(xics_host == NULL);
381	irq_set_default_host(xics_host);
382	}
383
384	void __init xics_register_ics(struct ics *ics)
385	{
386	list_add(&ics->link, &ics_list);
387	}
388
389	static void __init xics_get_server_size(void)
390	{
391	struct device_node *np;
392	const u32 *isize;
393
394	/* We fetch the interrupt server size from the first ICS node
395	* we find if any
396	*/
397	np = of_find_compatible_node(NULL, NULL, "ibm,ppc-xics");
398	if (!np)
399	return;
400	isize = of_get_property(np, "ibm,interrupt-server#-size", NULL);
401	if (!isize)
402	return;
403	xics_interrupt_server_size = *isize;
404	of_node_put(np);
405	}
406
407	void __init xics_init(void)
408	{
409	int rc = -1;
410
411	/* Fist locate ICP */
412	#ifdef CONFIG_PPC_ICP_HV
413	if (firmware_has_feature(FW_FEATURE_LPAR))
414	rc = icp_hv_init();
415	#endif
416	#ifdef CONFIG_PPC_ICP_NATIVE
417	if (rc < 0)
418	rc = icp_native_init();
419	#endif
420	if (rc < 0) {
421	pr_warning("XICS: Cannot find a Presentation Controller !\n");
422	return;
423	}
424
425	/* Copy get_irq callback over to ppc_md */
426	ppc_md.get_irq = icp_ops->get_irq;
427
428	/* Patch up IPI chip EOI */
429	xics_ipi_chip.irq_eoi = icp_ops->eoi;
430
431	/* Now locate ICS */
432	#ifdef CONFIG_PPC_ICS_RTAS
433	rc = ics_rtas_init();
434	#endif
435	if (rc < 0)
436	pr_warning("XICS: Cannot find a Source Controller !\n");
437
438	/* Initialize common bits */
439	xics_get_server_size();
440	xics_update_irq_servers();
441	xics_init_host();
442	xics_setup_cpu();
443	}