[deliverable/linux.git] / arch / ia64 / xen / irq_xen.c

/******************************************************************************
 * arch/ia64/xen/irq_xen.c
 *
 * Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
 *                    VA Linux Systems Japan K.K.
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/cpu.h>

#include <xen/interface/xen.h>
#include <xen/interface/callback.h>
#include <xen/events.h>

#include <asm/xen/privop.h>

#include "irq_xen.h"

/***************************************************************************
 * pv_irq_ops
 * irq operations
 */

static int
xen_assign_irq_vector(int irq)
{
	struct physdev_irq irq_op;

	irq_op.irq = irq;
	if (HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op))
		return -ENOSPC;

	return irq_op.vector;
}

static void
xen_free_irq_vector(int vector)
{
	struct physdev_irq irq_op;

	if (vector < IA64_FIRST_DEVICE_VECTOR ||
	    vector > IA64_LAST_DEVICE_VECTOR)
		return;

	irq_op.vector = vector;
	if (HYPERVISOR_physdev_op(PHYSDEVOP_free_irq_vector, &irq_op))
		printk(KERN_WARNING "%s: xen_free_irq_vecotr fail vector=%d\n",
		       __func__, vector);
}


static DEFINE_PER_CPU(int, timer_irq) = -1;
static DEFINE_PER_CPU(int, ipi_irq) = -1;
static DEFINE_PER_CPU(int, resched_irq) = -1;
static DEFINE_PER_CPU(int, cmc_irq) = -1;
static DEFINE_PER_CPU(int, cmcp_irq) = -1;
static DEFINE_PER_CPU(int, cpep_irq) = -1;
#define NAME_SIZE	15
static DEFINE_PER_CPU(char[NAME_SIZE], timer_name);
static DEFINE_PER_CPU(char[NAME_SIZE], ipi_name);
static DEFINE_PER_CPU(char[NAME_SIZE], resched_name);
static DEFINE_PER_CPU(char[NAME_SIZE], cmc_name);
static DEFINE_PER_CPU(char[NAME_SIZE], cmcp_name);
static DEFINE_PER_CPU(char[NAME_SIZE], cpep_name);
#undef NAME_SIZE

struct saved_irq {
	unsigned int irq;
	struct irqaction *action;
};
/* 16 should be far optimistic value, since only several percpu irqs
 * are registered early.
 */
#define MAX_LATE_IRQ	16
static struct saved_irq saved_percpu_irqs[MAX_LATE_IRQ];
static unsigned short late_irq_cnt;
static unsigned short saved_irq_cnt;
static int xen_slab_ready;

#ifdef CONFIG_SMP
/* Dummy stub. Though we may check XEN_RESCHEDULE_VECTOR before __do_IRQ,
 * it ends up to issue several memory accesses upon percpu data and
 * thus adds unnecessary traffic to other paths.
 */
static irqreturn_t
xen_dummy_handler(int irq, void *dev_id)
{

	return IRQ_HANDLED;
}

static struct irqaction xen_ipi_irqaction = {
	.handler =	handle_IPI,
	.flags =	IRQF_DISABLED,
	.name =		"IPI"
};

static struct irqaction xen_resched_irqaction = {
	.handler =	xen_dummy_handler,
	.flags =	IRQF_DISABLED,
	.name =		"resched"
};

static struct irqaction xen_tlb_irqaction = {
	.handler =	xen_dummy_handler,
	.flags =	IRQF_DISABLED,
	.name =		"tlb_flush"
};
#endif

/*
 * This is xen version percpu irq registration, which needs bind
 * to xen specific evtchn sub-system. One trick here is that xen
 * evtchn binding interface depends on kmalloc because related
 * port needs to be freed at device/cpu down. So we cache the
 * registration on BSP before slab is ready and then deal them
 * at later point. For rest instances happening after slab ready,
 * we hook them to xen evtchn immediately.
 *
 * FIXME: MCA is not supported by far, and thus "nomca" boot param is
 * required.
 */
static void
__xen_register_percpu_irq(unsigned int cpu, unsigned int vec,
			struct irqaction *action, int save)
{
	struct irq_desc *desc;
	int irq = 0;

	if (xen_slab_ready) {
		switch (vec) {
		case IA64_TIMER_VECTOR:
			snprintf(per_cpu(timer_name, cpu),
				 sizeof(per_cpu(timer_name, cpu)),
				 "%s%d", action->name, cpu);
			irq = bind_virq_to_irqhandler(VIRQ_ITC, cpu,
				action->handler, action->flags,
				per_cpu(timer_name, cpu), action->dev_id);
			per_cpu(timer_irq, cpu) = irq;
			break;
		case IA64_IPI_RESCHEDULE:
			snprintf(per_cpu(resched_name, cpu),
				 sizeof(per_cpu(resched_name, cpu)),
				 "%s%d", action->name, cpu);
			irq = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR, cpu,
				action->handler, action->flags,
				per_cpu(resched_name, cpu), action->dev_id);
			per_cpu(resched_irq, cpu) = irq;
			break;
		case IA64_IPI_VECTOR:
			snprintf(per_cpu(ipi_name, cpu),
				 sizeof(per_cpu(ipi_name, cpu)),
				 "%s%d", action->name, cpu);
			irq = bind_ipi_to_irqhandler(XEN_IPI_VECTOR, cpu,
				action->handler, action->flags,
				per_cpu(ipi_name, cpu), action->dev_id);
			per_cpu(ipi_irq, cpu) = irq;
			break;
		case IA64_CMC_VECTOR:
			snprintf(per_cpu(cmc_name, cpu),
				 sizeof(per_cpu(cmc_name, cpu)),
				 "%s%d", action->name, cpu);
			irq = bind_virq_to_irqhandler(VIRQ_MCA_CMC, cpu,
						      action->handler,
						      action->flags,
						      per_cpu(cmc_name, cpu),
						      action->dev_id);
			per_cpu(cmc_irq, cpu) = irq;
			break;
		case IA64_CMCP_VECTOR:
			snprintf(per_cpu(cmcp_name, cpu),
				 sizeof(per_cpu(cmcp_name, cpu)),
				 "%s%d", action->name, cpu);
			irq = bind_ipi_to_irqhandler(XEN_CMCP_VECTOR, cpu,
						     action->handler,
						     action->flags,
						     per_cpu(cmcp_name, cpu),
						     action->dev_id);
			per_cpu(cmcp_irq, cpu) = irq;
			break;
		case IA64_CPEP_VECTOR:
			snprintf(per_cpu(cpep_name, cpu),
				 sizeof(per_cpu(cpep_name, cpu)),
				 "%s%d", action->name, cpu);
			irq = bind_ipi_to_irqhandler(XEN_CPEP_VECTOR, cpu,
						     action->handler,
						     action->flags,
						     per_cpu(cpep_name, cpu),
						     action->dev_id);
			per_cpu(cpep_irq, cpu) = irq;
			break;
		case IA64_CPE_VECTOR:
		case IA64_MCA_RENDEZ_VECTOR:
		case IA64_PERFMON_VECTOR:
		case IA64_MCA_WAKEUP_VECTOR:
		case IA64_SPURIOUS_INT_VECTOR:
			/* No need to complain, these aren't supported. */
			break;
		default:
			printk(KERN_WARNING "Percpu irq %d is unsupported "
			       "by xen!\n", vec);
			break;
		}
		BUG_ON(irq < 0);

		if (irq > 0) {
			/*
			 * Mark percpu.  Without this, migrate_irqs() will
			 * mark the interrupt for migrations and trigger it
			 * on cpu hotplug.
			 */
			desc = irq_desc + irq;
			desc->status |= IRQ_PER_CPU;
		}
	}

	/* For BSP, we cache registered percpu irqs, and then re-walk
	 * them when initializing APs
	 */
	if (!cpu && save) {
		BUG_ON(saved_irq_cnt == MAX_LATE_IRQ);
		saved_percpu_irqs[saved_irq_cnt].irq = vec;
		saved_percpu_irqs[saved_irq_cnt].action = action;
		saved_irq_cnt++;
		if (!xen_slab_ready)
			late_irq_cnt++;
	}
}

static void
xen_register_percpu_irq(ia64_vector vec, struct irqaction *action)
{
	__xen_register_percpu_irq(smp_processor_id(), vec, action, 1);
}

static void
xen_bind_early_percpu_irq(void)
{
	int i;

	xen_slab_ready = 1;
	/* There's no race when accessing this cached array, since only
	 * BSP will face with such step shortly
	 */
	for (i = 0; i < late_irq_cnt; i++)
		__xen_register_percpu_irq(smp_processor_id(),
					  saved_percpu_irqs[i].irq,
					  saved_percpu_irqs[i].action, 0);
}

/* FIXME: There's no obvious point to check whether slab is ready. So
 * a hack is used here by utilizing a late time hook.
 */

#ifdef CONFIG_HOTPLUG_CPU
static int __devinit
unbind_evtchn_callback(struct notifier_block *nfb,
		       unsigned long action, void *hcpu)
{
	unsigned int cpu = (unsigned long)hcpu;

	if (action == CPU_DEAD) {
		/* Unregister evtchn.  */
		if (per_cpu(cpep_irq, cpu) >= 0) {
			unbind_from_irqhandler(per_cpu(cpep_irq, cpu), NULL);
			per_cpu(cpep_irq, cpu) = -1;
		}
		if (per_cpu(cmcp_irq, cpu) >= 0) {
			unbind_from_irqhandler(per_cpu(cmcp_irq, cpu), NULL);
			per_cpu(cmcp_irq, cpu) = -1;
		}
		if (per_cpu(cmc_irq, cpu) >= 0) {
			unbind_from_irqhandler(per_cpu(cmc_irq, cpu), NULL);
			per_cpu(cmc_irq, cpu) = -1;
		}
		if (per_cpu(ipi_irq, cpu) >= 0) {
			unbind_from_irqhandler(per_cpu(ipi_irq, cpu), NULL);
			per_cpu(ipi_irq, cpu) = -1;
		}
		if (per_cpu(resched_irq, cpu) >= 0) {
			unbind_from_irqhandler(per_cpu(resched_irq, cpu),
						NULL);
			per_cpu(resched_irq, cpu) = -1;
		}
		if (per_cpu(timer_irq, cpu) >= 0) {
			unbind_from_irqhandler(per_cpu(timer_irq, cpu), NULL);
			per_cpu(timer_irq, cpu) = -1;
		}
	}
	return NOTIFY_OK;
}

static struct notifier_block unbind_evtchn_notifier = {
	.notifier_call = unbind_evtchn_callback,
	.priority = 0
};
#endif

void xen_smp_intr_init_early(unsigned int cpu)
{
#ifdef CONFIG_SMP
	unsigned int i;

	for (i = 0; i < saved_irq_cnt; i++)
		__xen_register_percpu_irq(cpu, saved_percpu_irqs[i].irq,
					  saved_percpu_irqs[i].action, 0);
#endif
}

void xen_smp_intr_init(void)
{
#ifdef CONFIG_SMP
	unsigned int cpu = smp_processor_id();
	struct callback_register event = {
		.type = CALLBACKTYPE_event,
		.address = { .ip = (unsigned long)&xen_event_callback },
	};

	if (cpu == 0) {
		/* Initialization was already done for boot cpu.  */
#ifdef CONFIG_HOTPLUG_CPU
		/* Register the notifier only once.  */
		register_cpu_notifier(&unbind_evtchn_notifier);
#endif
		return;
	}

	/* This should be piggyback when setup vcpu guest context */
	BUG_ON(HYPERVISOR_callback_op(CALLBACKOP_register, &event));
#endif /* CONFIG_SMP */
}

void __init
xen_irq_init(void)
{
	struct callback_register event = {
		.type = CALLBACKTYPE_event,
		.address = { .ip = (unsigned long)&xen_event_callback },
	};

	xen_init_IRQ();
	BUG_ON(HYPERVISOR_callback_op(CALLBACKOP_register, &event));
	late_time_init = xen_bind_early_percpu_irq;
}

void
xen_platform_send_ipi(int cpu, int vector, int delivery_mode, int redirect)
{
#ifdef CONFIG_SMP
	/* TODO: we need to call vcpu_up here */
	if (unlikely(vector == ap_wakeup_vector)) {
		/* XXX
		 * This should be in __cpu_up(cpu) in ia64 smpboot.c
		 * like x86. But don't want to modify it,
		 * keep it untouched.
		 */
		xen_smp_intr_init_early(cpu);

		xen_send_ipi(cpu, vector);
		/* vcpu_prepare_and_up(cpu); */
		return;
	}
#endif

	switch (vector) {
	case IA64_IPI_VECTOR:
		xen_send_IPI_one(cpu, XEN_IPI_VECTOR);
		break;
	case IA64_IPI_RESCHEDULE:
		xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
		break;
	case IA64_CMCP_VECTOR:
		xen_send_IPI_one(cpu, XEN_CMCP_VECTOR);
		break;
	case IA64_CPEP_VECTOR:
		xen_send_IPI_one(cpu, XEN_CPEP_VECTOR);
		break;
	case IA64_TIMER_VECTOR: {
		/* this is used only once by check_sal_cache_flush()
		   at boot time */
		static int used = 0;
		if (!used) {
			xen_send_ipi(cpu, IA64_TIMER_VECTOR);
			used = 1;
			break;
		}
		/* fallthrough */
	}
	default:
		printk(KERN_WARNING "Unsupported IPI type 0x%x\n",
		       vector);
		notify_remote_via_irq(0); /* defaults to 0 irq */
		break;
	}
}

static void __init
xen_register_ipi(void)
{
#ifdef CONFIG_SMP
	register_percpu_irq(IA64_IPI_VECTOR, &xen_ipi_irqaction);
	register_percpu_irq(IA64_IPI_RESCHEDULE, &xen_resched_irqaction);
	register_percpu_irq(IA64_IPI_LOCAL_TLB_FLUSH, &xen_tlb_irqaction);
#endif
}

static void
xen_resend_irq(unsigned int vector)
{
	(void)resend_irq_on_evtchn(vector);
}

const struct pv_irq_ops xen_irq_ops __initdata = {
	.register_ipi = xen_register_ipi,

	.assign_irq_vector = xen_assign_irq_vector,
	.free_irq_vector = xen_free_irq_vector,
	.register_percpu_irq = xen_register_percpu_irq,

	.resend_irq = xen_resend_irq,
};
Commit	Line	Data
7477de98 IY	1	/******************************************************************************
	2	* arch/ia64/xen/irq_xen.c
	3	*
	4	* Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
	5	* VA Linux Systems Japan K.K.
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*
	21	*/
	22
	23	#include <linux/cpu.h>
	24
	25	#include <xen/interface/xen.h>
	26	#include <xen/interface/callback.h>
	27	#include <xen/events.h>
	28
	29	#include <asm/xen/privop.h>
	30
	31	#include "irq_xen.h"
	32
	33	/***************************************************************************
	34	* pv_irq_ops
	35	* irq operations
	36	*/
	37
	38	static int
	39	xen_assign_irq_vector(int irq)
	40	{
	41	struct physdev_irq irq_op;
	42
	43	irq_op.irq = irq;
	44	if (HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op))
	45	return -ENOSPC;
	46
	47	return irq_op.vector;
	48	}
	49
	50	static void
	51	xen_free_irq_vector(int vector)
	52	{
	53	struct physdev_irq irq_op;
	54
	55	if (vector < IA64_FIRST_DEVICE_VECTOR \|\|
	56	vector > IA64_LAST_DEVICE_VECTOR)
	57	return;
	58
	59	irq_op.vector = vector;
	60	if (HYPERVISOR_physdev_op(PHYSDEVOP_free_irq_vector, &irq_op))
	61	printk(KERN_WARNING "%s: xen_free_irq_vecotr fail vector=%d\n",
	62	__func__, vector);
	63	}
	64
65
66	static DEFINE_PER_CPU(int, timer_irq) = -1;
67	static DEFINE_PER_CPU(int, ipi_irq) = -1;
68	static DEFINE_PER_CPU(int, resched_irq) = -1;
69	static DEFINE_PER_CPU(int, cmc_irq) = -1;
70	static DEFINE_PER_CPU(int, cmcp_irq) = -1;
71	static DEFINE_PER_CPU(int, cpep_irq) = -1;
72	#define NAME_SIZE 15
73	static DEFINE_PER_CPU(char[NAME_SIZE], timer_name);
74	static DEFINE_PER_CPU(char[NAME_SIZE], ipi_name);
75	static DEFINE_PER_CPU(char[NAME_SIZE], resched_name);
76	static DEFINE_PER_CPU(char[NAME_SIZE], cmc_name);
77	static DEFINE_PER_CPU(char[NAME_SIZE], cmcp_name);
78	static DEFINE_PER_CPU(char[NAME_SIZE], cpep_name);
79	#undef NAME_SIZE
80
81	struct saved_irq {
82	unsigned int irq;
83	struct irqaction *action;
84	};
85	/* 16 should be far optimistic value, since only several percpu irqs
86	* are registered early.
87	*/
88	#define MAX_LATE_IRQ 16
89	static struct saved_irq saved_percpu_irqs[MAX_LATE_IRQ];
90	static unsigned short late_irq_cnt;
91	static unsigned short saved_irq_cnt;
92	static int xen_slab_ready;
93
94	#ifdef CONFIG_SMP
95	/* Dummy stub. Though we may check XEN_RESCHEDULE_VECTOR before __do_IRQ,
96	* it ends up to issue several memory accesses upon percpu data and
97	* thus adds unnecessary traffic to other paths.
98	*/
99	static irqreturn_t
100	xen_dummy_handler(int irq, void *dev_id)
101	{
102
103	return IRQ_HANDLED;
104	}
105
106	static struct irqaction xen_ipi_irqaction = {
107	.handler = handle_IPI,
108	.flags = IRQF_DISABLED,
109	.name = "IPI"
110	};
111
112	static struct irqaction xen_resched_irqaction = {
113	.handler = xen_dummy_handler,
114	.flags = IRQF_DISABLED,
115	.name = "resched"
116	};
117
118	static struct irqaction xen_tlb_irqaction = {
119	.handler = xen_dummy_handler,
120	.flags = IRQF_DISABLED,
121	.name = "tlb_flush"
122	};
123	#endif
124
125	/*
126	* This is xen version percpu irq registration, which needs bind
127	* to xen specific evtchn sub-system. One trick here is that xen
128	* evtchn binding interface depends on kmalloc because related
129	* port needs to be freed at device/cpu down. So we cache the
130	* registration on BSP before slab is ready and then deal them
131	* at later point. For rest instances happening after slab ready,
132	* we hook them to xen evtchn immediately.
133	*
134	* FIXME: MCA is not supported by far, and thus "nomca" boot param is
135	* required.
136	*/
137	static void
138	__xen_register_percpu_irq(unsigned int cpu, unsigned int vec,
139	struct irqaction *action, int save)
140	{
86bc3dfe	141	struct irq_desc *desc;
7477de98 IY	142	int irq = 0;
	143
	144	if (xen_slab_ready) {
	145	switch (vec) {
	146	case IA64_TIMER_VECTOR:
	147	snprintf(per_cpu(timer_name, cpu),
	148	sizeof(per_cpu(timer_name, cpu)),
	149	"%s%d", action->name, cpu);
	150	irq = bind_virq_to_irqhandler(VIRQ_ITC, cpu,
	151	action->handler, action->flags,
	152	per_cpu(timer_name, cpu), action->dev_id);
	153	per_cpu(timer_irq, cpu) = irq;
	154	break;
	155	case IA64_IPI_RESCHEDULE:
	156	snprintf(per_cpu(resched_name, cpu),
	157	sizeof(per_cpu(resched_name, cpu)),
	158	"%s%d", action->name, cpu);
	159	irq = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR, cpu,
	160	action->handler, action->flags,
	161	per_cpu(resched_name, cpu), action->dev_id);
	162	per_cpu(resched_irq, cpu) = irq;
	163	break;
	164	case IA64_IPI_VECTOR:
	165	snprintf(per_cpu(ipi_name, cpu),
	166	sizeof(per_cpu(ipi_name, cpu)),
	167	"%s%d", action->name, cpu);
	168	irq = bind_ipi_to_irqhandler(XEN_IPI_VECTOR, cpu,
	169	action->handler, action->flags,
	170	per_cpu(ipi_name, cpu), action->dev_id);
	171	per_cpu(ipi_irq, cpu) = irq;
	172	break;
	173	case IA64_CMC_VECTOR:
	174	snprintf(per_cpu(cmc_name, cpu),
	175	sizeof(per_cpu(cmc_name, cpu)),
	176	"%s%d", action->name, cpu);
	177	irq = bind_virq_to_irqhandler(VIRQ_MCA_CMC, cpu,
	178	action->handler,
	179	action->flags,
	180	per_cpu(cmc_name, cpu),
	181	action->dev_id);
	182	per_cpu(cmc_irq, cpu) = irq;
	183	break;
	184	case IA64_CMCP_VECTOR:
	185	snprintf(per_cpu(cmcp_name, cpu),
	186	sizeof(per_cpu(cmcp_name, cpu)),
	187	"%s%d", action->name, cpu);
	188	irq = bind_ipi_to_irqhandler(XEN_CMCP_VECTOR, cpu,
	189	action->handler,
	190	action->flags,
	191	per_cpu(cmcp_name, cpu),
	192	action->dev_id);
	193	per_cpu(cmcp_irq, cpu) = irq;
	194	break;
	195	case IA64_CPEP_VECTOR:
	196	snprintf(per_cpu(cpep_name, cpu),
	197	sizeof(per_cpu(cpep_name, cpu)),
	198	"%s%d", action->name, cpu);
	199	irq = bind_ipi_to_irqhandler(XEN_CPEP_VECTOR, cpu,
	200	action->handler,
	201	action->flags,
	202	per_cpu(cpep_name, cpu),
	203	action->dev_id);
	204	per_cpu(cpep_irq, cpu) = irq;
	205	break;
206	case IA64_CPE_VECTOR:
207	case IA64_MCA_RENDEZ_VECTOR:
208	case IA64_PERFMON_VECTOR:
209	case IA64_MCA_WAKEUP_VECTOR:
210	case IA64_SPURIOUS_INT_VECTOR:
211	/* No need to complain, these aren't supported. */
212	break;
213	default:
214	printk(KERN_WARNING "Percpu irq %d is unsupported "
215	"by xen!\n", vec);
216	break;
217	}
218	BUG_ON(irq < 0);
219
220	if (irq > 0) {
221	/*
222	* Mark percpu. Without this, migrate_irqs() will
223	* mark the interrupt for migrations and trigger it
224	* on cpu hotplug.
225	*/
226	desc = irq_desc + irq;
227	desc->status \|= IRQ_PER_CPU;
228	}
229	}
230
231	/* For BSP, we cache registered percpu irqs, and then re-walk
232	* them when initializing APs
233	*/
234	if (!cpu && save) {
235	BUG_ON(saved_irq_cnt == MAX_LATE_IRQ);
236	saved_percpu_irqs[saved_irq_cnt].irq = vec;
237	saved_percpu_irqs[saved_irq_cnt].action = action;
238	saved_irq_cnt++;
239	if (!xen_slab_ready)
240	late_irq_cnt++;
241	}
242	}
243
244	static void
245	xen_register_percpu_irq(ia64_vector vec, struct irqaction *action)
246	{
247	__xen_register_percpu_irq(smp_processor_id(), vec, action, 1);
248	}
249
250	static void
251	xen_bind_early_percpu_irq(void)
252	{
253	int i;
254
255	xen_slab_ready = 1;
256	/* There's no race when accessing this cached array, since only
257	* BSP will face with such step shortly
258	*/
259	for (i = 0; i < late_irq_cnt; i++)
260	__xen_register_percpu_irq(smp_processor_id(),
261	saved_percpu_irqs[i].irq,
262	saved_percpu_irqs[i].action, 0);
263	}
264
265	/* FIXME: There's no obvious point to check whether slab is ready. So
266	* a hack is used here by utilizing a late time hook.
267	*/
268
269	#ifdef CONFIG_HOTPLUG_CPU
270	static int __devinit
271	unbind_evtchn_callback(struct notifier_block *nfb,
272	unsigned long action, void *hcpu)
273	{
274	unsigned int cpu = (unsigned long)hcpu;
275
276	if (action == CPU_DEAD) {
277	/* Unregister evtchn. */
278	if (per_cpu(cpep_irq, cpu) >= 0) {
279	unbind_from_irqhandler(per_cpu(cpep_irq, cpu), NULL);
280	per_cpu(cpep_irq, cpu) = -1;
281	}
282	if (per_cpu(cmcp_irq, cpu) >= 0) {
283	unbind_from_irqhandler(per_cpu(cmcp_irq, cpu), NULL);
284	per_cpu(cmcp_irq, cpu) = -1;
285	}
286	if (per_cpu(cmc_irq, cpu) >= 0) {
287	unbind_from_irqhandler(per_cpu(cmc_irq, cpu), NULL);
288	per_cpu(cmc_irq, cpu) = -1;
289	}
290	if (per_cpu(ipi_irq, cpu) >= 0) {
291	unbind_from_irqhandler(per_cpu(ipi_irq, cpu), NULL);
292	per_cpu(ipi_irq, cpu) = -1;
293	}
294	if (per_cpu(resched_irq, cpu) >= 0) {
295	unbind_from_irqhandler(per_cpu(resched_irq, cpu),
296	NULL);
297	per_cpu(resched_irq, cpu) = -1;
298	}
299	if (per_cpu(timer_irq, cpu) >= 0) {
300	unbind_from_irqhandler(per_cpu(timer_irq, cpu), NULL);
301	per_cpu(timer_irq, cpu) = -1;
302	}
303	}
304	return NOTIFY_OK;
305	}
306
307	static struct notifier_block unbind_evtchn_notifier = {
308	.notifier_call = unbind_evtchn_callback,
309	.priority = 0
310	};
311	#endif
312
313	void xen_smp_intr_init_early(unsigned int cpu)
314	{
315	#ifdef CONFIG_SMP
316	unsigned int i;
317
318	for (i = 0; i < saved_irq_cnt; i++)
319	__xen_register_percpu_irq(cpu, saved_percpu_irqs[i].irq,
320	saved_percpu_irqs[i].action, 0);
321	#endif
322	}
323
324	void xen_smp_intr_init(void)
325	{
326	#ifdef CONFIG_SMP
327	unsigned int cpu = smp_processor_id();
328	struct callback_register event = {
329	.type = CALLBACKTYPE_event,
330	.address = { .ip = (unsigned long)&xen_event_callback },
331	};
332
333	if (cpu == 0) {
334	/* Initialization was already done for boot cpu. */
335	#ifdef CONFIG_HOTPLUG_CPU
336	/* Register the notifier only once. */
337	register_cpu_notifier(&unbind_evtchn_notifier);
338	#endif
339	return;
340	}
341
342	/* This should be piggyback when setup vcpu guest context */
343	BUG_ON(HYPERVISOR_callback_op(CALLBACKOP_register, &event));
344	#endif /* CONFIG_SMP */
345	}
346
347	void __init
348	xen_irq_init(void)
349	{
350	struct callback_register event = {
351	.type = CALLBACKTYPE_event,
352	.address = { .ip = (unsigned long)&xen_event_callback },
353	};
354
355	xen_init_IRQ();
356	BUG_ON(HYPERVISOR_callback_op(CALLBACKOP_register, &event));
357	late_time_init = xen_bind_early_percpu_irq;
358	}
359
360	void
361	xen_platform_send_ipi(int cpu, int vector, int delivery_mode, int redirect)
362	{
363	#ifdef CONFIG_SMP
364	/* TODO: we need to call vcpu_up here */
365	if (unlikely(vector == ap_wakeup_vector)) {
366	/* XXX
367	* This should be in __cpu_up(cpu) in ia64 smpboot.c
368	* like x86. But don't want to modify it,
369	* keep it untouched.
370	*/
371	xen_smp_intr_init_early(cpu);
372
373	xen_send_ipi(cpu, vector);
374	/* vcpu_prepare_and_up(cpu); */
375	return;
376	}
377	#endif
378
379	switch (vector) {
380	case IA64_IPI_VECTOR:
381	xen_send_IPI_one(cpu, XEN_IPI_VECTOR);
382	break;
383	case IA64_IPI_RESCHEDULE:
384	xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
385	break;
386	case IA64_CMCP_VECTOR:
387	xen_send_IPI_one(cpu, XEN_CMCP_VECTOR);
388	break;
389	case IA64_CPEP_VECTOR:
390	xen_send_IPI_one(cpu, XEN_CPEP_VECTOR);
391	break;
392	case IA64_TIMER_VECTOR: {
393	/* this is used only once by check_sal_cache_flush()
394	at boot time */
395	static int used = 0;
396	if (!used) {
397	xen_send_ipi(cpu, IA64_TIMER_VECTOR);
398	used = 1;
399	break;
400	}
401	/* fallthrough */
402	}
403	default:
404	printk(KERN_WARNING "Unsupported IPI type 0x%x\n",
405	vector);
406	notify_remote_via_irq(0); /* defaults to 0 irq */
407	break;
408	}
409	}
410
411	static void __init
412	xen_register_ipi(void)
413	{
414	#ifdef CONFIG_SMP
415	register_percpu_irq(IA64_IPI_VECTOR, &xen_ipi_irqaction);
416	register_percpu_irq(IA64_IPI_RESCHEDULE, &xen_resched_irqaction);
417	register_percpu_irq(IA64_IPI_LOCAL_TLB_FLUSH, &xen_tlb_irqaction);
418	#endif
419	}
420
421	static void
422	xen_resend_irq(unsigned int vector)
423	{
424	(void)resend_irq_on_evtchn(vector);
425	}
426
427	const struct pv_irq_ops xen_irq_ops __initdata = {
428	.register_ipi = xen_register_ipi,
429
430	.assign_irq_vector = xen_assign_irq_vector,
431	.free_irq_vector = xen_free_irq_vector,
432	.register_percpu_irq = xen_register_percpu_irq,
433
434	.resend_irq = xen_resend_irq,
435	};