[deliverable/linux.git] / arch / ia64 / kernel / irq_ia64.c

/*
 * linux/arch/ia64/kernel/irq_ia64.c
 *
 * Copyright (C) 1998-2001 Hewlett-Packard Co
 *	Stephane Eranian <eranian@hpl.hp.com>
 *	David Mosberger-Tang <davidm@hpl.hp.com>
 *
 *  6/10/99: Updated to bring in sync with x86 version to facilitate
 *	     support for SMP and different interrupt controllers.
 *
 * 09/15/00 Goutham Rao <goutham.rao@intel.com> Implemented pci_irq_to_vector
 *                      PCI to vector allocation routine.
 * 04/14/2004 Ashok Raj <ashok.raj@intel.com>
 *						Added CPU Hotplug handling for IPF.
 */

#include <linux/module.h>

#include <linux/jiffies.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/kernel_stat.h>
#include <linux/slab.h>
#include <linux/ptrace.h>
#include <linux/random.h>	/* for rand_initialize_irq() */
#include <linux/signal.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/threads.h>
#include <linux/bitops.h>
#include <linux/irq.h>

#include <asm/delay.h>
#include <asm/intrinsics.h>
#include <asm/io.h>
#include <asm/hw_irq.h>
#include <asm/machvec.h>
#include <asm/pgtable.h>
#include <asm/system.h>

#ifdef CONFIG_PERFMON
# include <asm/perfmon.h>
#endif

#define IRQ_DEBUG	0

/* These can be overridden in platform_irq_init */
int ia64_first_device_vector = IA64_DEF_FIRST_DEVICE_VECTOR;
int ia64_last_device_vector = IA64_DEF_LAST_DEVICE_VECTOR;

/* default base addr of IPI table */
void __iomem *ipi_base_addr = ((void __iomem *)
			       (__IA64_UNCACHED_OFFSET | IA64_IPI_DEFAULT_BASE_ADDR));

/*
 * Legacy IRQ to IA-64 vector translation table.
 */
__u8 isa_irq_to_vector_map[16] = {
	/* 8259 IRQ translation, first 16 entries */
	0x2f, 0x20, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x29,
	0x28, 0x27, 0x26, 0x25, 0x24, 0x23, 0x22, 0x21
};
EXPORT_SYMBOL(isa_irq_to_vector_map);

static unsigned long ia64_vector_mask[BITS_TO_LONGS(IA64_MAX_DEVICE_VECTORS)];

int
assign_irq_vector (int irq)
{
	int pos, vector;
 again:
	pos = find_first_zero_bit(ia64_vector_mask, IA64_NUM_DEVICE_VECTORS);
	vector = IA64_FIRST_DEVICE_VECTOR + pos;
	if (vector > IA64_LAST_DEVICE_VECTOR)
		return -ENOSPC;
	if (test_and_set_bit(pos, ia64_vector_mask))
		goto again;
	return vector;
}

void
free_irq_vector (int vector)
{
	int pos;

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

	pos = vector - IA64_FIRST_DEVICE_VECTOR;
	if (!test_and_clear_bit(pos, ia64_vector_mask))
		printk(KERN_WARNING "%s: double free!\n", __FUNCTION__);
}

int
reserve_irq_vector (int vector)
{
	int pos;

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

	pos = vector - IA64_FIRST_DEVICE_VECTOR;
	return test_and_set_bit(pos, ia64_vector_mask);
}

/*
 * Dynamic irq allocate and deallocation for MSI
 */
int create_irq(void)
{
	int vector = assign_irq_vector(AUTO_ASSIGN);

	if (vector >= 0)
		dynamic_irq_init(vector);

	return vector;
}

void destroy_irq(unsigned int irq)
{
	dynamic_irq_cleanup(irq);
	free_irq_vector(irq);
}

#ifdef CONFIG_SMP
#	define IS_RESCHEDULE(vec)	(vec == IA64_IPI_RESCHEDULE)
#else
#	define IS_RESCHEDULE(vec)	(0)
#endif
/*
 * That's where the IVT branches when we get an external
 * interrupt. This branches to the correct hardware IRQ handler via
 * function ptr.
 */
void
ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
{
	struct pt_regs *old_regs = set_irq_regs(regs);
	unsigned long saved_tpr;

#if IRQ_DEBUG
	{
		unsigned long bsp, sp;

		/*
		 * Note: if the interrupt happened while executing in
		 * the context switch routine (ia64_switch_to), we may
		 * get a spurious stack overflow here.  This is
		 * because the register and the memory stack are not
		 * switched atomically.
		 */
		bsp = ia64_getreg(_IA64_REG_AR_BSP);
		sp = ia64_getreg(_IA64_REG_SP);

		if ((sp - bsp) < 1024) {
			static unsigned char count;
			static long last_time;

			if (jiffies - last_time > 5*HZ)
				count = 0;
			if (++count < 5) {
				last_time = jiffies;
				printk("ia64_handle_irq: DANGER: less than "
				       "1KB of free stack space!!\n"
				       "(bsp=0x%lx, sp=%lx)\n", bsp, sp);
			}
		}
	}
#endif /* IRQ_DEBUG */

	/*
	 * Always set TPR to limit maximum interrupt nesting depth to
	 * 16 (without this, it would be ~240, which could easily lead
	 * to kernel stack overflows).
	 */
	irq_enter();
	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
	ia64_srlz_d();
	while (vector != IA64_SPURIOUS_INT_VECTOR) {
		if (unlikely(IS_RESCHEDULE(vector)))
			 kstat_this_cpu.irqs[vector]++;
		else {
			ia64_setreg(_IA64_REG_CR_TPR, vector);
			ia64_srlz_d();

			generic_handle_irq(local_vector_to_irq(vector));

			/*
			 * Disable interrupts and send EOI:
			 */
			local_irq_disable();
			ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
		}
		ia64_eoi();
		vector = ia64_get_ivr();
	}
	/*
	 * This must be done *after* the ia64_eoi().  For example, the keyboard softirq
	 * handler needs to be able to wait for further keyboard interrupts, which can't
	 * come through until ia64_eoi() has been done.
	 */
	irq_exit();
	set_irq_regs(old_regs);
}

#ifdef CONFIG_HOTPLUG_CPU
/*
 * This function emulates a interrupt processing when a cpu is about to be
 * brought down.
 */
void ia64_process_pending_intr(void)
{
	ia64_vector vector;
	unsigned long saved_tpr;
	extern unsigned int vectors_in_migration[NR_IRQS];

	vector = ia64_get_ivr();

	 irq_enter();
	 saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
	 ia64_srlz_d();

	 /*
	  * Perform normal interrupt style processing
	  */
	while (vector != IA64_SPURIOUS_INT_VECTOR) {
		if (unlikely(IS_RESCHEDULE(vector)))
			 kstat_this_cpu.irqs[vector]++;
		else {
			struct pt_regs *old_regs = set_irq_regs(NULL);

			ia64_setreg(_IA64_REG_CR_TPR, vector);
			ia64_srlz_d();

			/*
			 * Now try calling normal ia64_handle_irq as it would have got called
			 * from a real intr handler. Try passing null for pt_regs, hopefully
			 * it will work. I hope it works!.
			 * Probably could shared code.
			 */
			vectors_in_migration[local_vector_to_irq(vector)]=0;
			generic_handle_irq(local_vector_to_irq(vector));
			set_irq_regs(old_regs);

			/*
			 * Disable interrupts and send EOI
			 */
			local_irq_disable();
			ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
		}
		ia64_eoi();
		vector = ia64_get_ivr();
	}
	irq_exit();
}
#endif


#ifdef CONFIG_SMP
extern irqreturn_t handle_IPI (int irq, void *dev_id);

static irqreturn_t dummy_handler (int irq, void *dev_id)
{
	BUG();
}

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

static struct irqaction resched_irqaction = {
	.handler =	dummy_handler,
	.flags =	SA_INTERRUPT,
	.name =		"resched"
};
#endif

void
register_percpu_irq (ia64_vector vec, struct irqaction *action)
{
	irq_desc_t *desc;
	unsigned int irq;

	for (irq = 0; irq < NR_IRQS; ++irq)
		if (irq_to_vector(irq) == vec) {
			desc = irq_desc + irq;
			desc->status |= IRQ_PER_CPU;
			desc->chip = &irq_type_ia64_lsapic;
			if (action)
				setup_irq(irq, action);
		}
}

void __init
init_IRQ (void)
{
	register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
#ifdef CONFIG_SMP
	register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
	register_percpu_irq(IA64_IPI_RESCHEDULE, &resched_irqaction);
#endif
#ifdef CONFIG_PERFMON
	pfm_init_percpu();
#endif
	platform_irq_init();
}

void
ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
{
	void __iomem *ipi_addr;
	unsigned long ipi_data;
	unsigned long phys_cpu_id;

#ifdef CONFIG_SMP
	phys_cpu_id = cpu_physical_id(cpu);
#else
	phys_cpu_id = (ia64_getreg(_IA64_REG_CR_LID) >> 16) & 0xffff;
#endif

	/*
	 * cpu number is in 8bit ID and 8bit EID
	 */

	ipi_data = (delivery_mode << 8) | (vector & 0xff);
	ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) | ((redirect & 1) << 3));

	writeq(ipi_data, ipi_addr);
}
Commit	Line	Data
1da177e4	1	/*
f30c2269	2	* linux/arch/ia64/kernel/irq_ia64.c
1da177e4 LT	3	*
	4	* Copyright (C) 1998-2001 Hewlett-Packard Co
	5	* Stephane Eranian <eranian@hpl.hp.com>
	6	* David Mosberger-Tang <davidm@hpl.hp.com>
	7	*
	8	* 6/10/99: Updated to bring in sync with x86 version to facilitate
	9	* support for SMP and different interrupt controllers.
	10	*
	11	* 09/15/00 Goutham Rao <goutham.rao@intel.com> Implemented pci_irq_to_vector
	12	* PCI to vector allocation routine.
	13	* 04/14/2004 Ashok Raj <ashok.raj@intel.com>
	14	* Added CPU Hotplug handling for IPF.
	15	*/
	16
1da177e4 LT	17	#include <linux/module.h>
	18
	19	#include <linux/jiffies.h>
	20	#include <linux/errno.h>
	21	#include <linux/init.h>
	22	#include <linux/interrupt.h>
	23	#include <linux/ioport.h>
	24	#include <linux/kernel_stat.h>
	25	#include <linux/slab.h>
	26	#include <linux/ptrace.h>
	27	#include <linux/random.h> /* for rand_initialize_irq() */
	28	#include <linux/signal.h>
	29	#include <linux/smp.h>
	30	#include <linux/smp_lock.h>
	31	#include <linux/threads.h>
	32	#include <linux/bitops.h>
b6cf2583	33	#include <linux/irq.h>
1da177e4 LT	34
	35	#include <asm/delay.h>
	36	#include <asm/intrinsics.h>
	37	#include <asm/io.h>
	38	#include <asm/hw_irq.h>
	39	#include <asm/machvec.h>
	40	#include <asm/pgtable.h>
	41	#include <asm/system.h>
	42
	43	#ifdef CONFIG_PERFMON
	44	# include <asm/perfmon.h>
	45	#endif
	46
	47	#define IRQ_DEBUG 0
	48
10083072 MM	49	/* These can be overridden in platform_irq_init */
	50	int ia64_first_device_vector = IA64_DEF_FIRST_DEVICE_VECTOR;
	51	int ia64_last_device_vector = IA64_DEF_LAST_DEVICE_VECTOR;
	52
1da177e4 LT	53	/* default base addr of IPI table */
	54	void __iomem ipi_base_addr = ((void __iomem )
	55	(__IA64_UNCACHED_OFFSET \| IA64_IPI_DEFAULT_BASE_ADDR));
	56
	57	/*
	58	* Legacy IRQ to IA-64 vector translation table.
	59	*/
	60	__u8 isa_irq_to_vector_map[16] = {
	61	/* 8259 IRQ translation, first 16 entries */
	62	0x2f, 0x20, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x29,
	63	0x28, 0x27, 0x26, 0x25, 0x24, 0x23, 0x22, 0x21
	64	};
	65	EXPORT_SYMBOL(isa_irq_to_vector_map);
	66
10083072	67	static unsigned long ia64_vector_mask[BITS_TO_LONGS(IA64_MAX_DEVICE_VECTORS)];
1da177e4 LT	68
1da177e4 LT	69	int
3b5cc090	70	assign_irq_vector (int irq)
1da177e4 LT	71	{
	72	int pos, vector;
	73	again:
	74	pos = find_first_zero_bit(ia64_vector_mask, IA64_NUM_DEVICE_VECTORS);
	75	vector = IA64_FIRST_DEVICE_VECTOR + pos;
	76	if (vector > IA64_LAST_DEVICE_VECTOR)
3b5cc090	77	return -ENOSPC;
1da177e4 LT	78	if (test_and_set_bit(pos, ia64_vector_mask))
	79	goto again;
	80	return vector;
	81	}
	82
	83	void
	84	free_irq_vector (int vector)
	85	{
	86	int pos;
	87
	88	if (vector < IA64_FIRST_DEVICE_VECTOR \|\| vector > IA64_LAST_DEVICE_VECTOR)
	89	return;
	90
	91	pos = vector - IA64_FIRST_DEVICE_VECTOR;
	92	if (!test_and_clear_bit(pos, ia64_vector_mask))
	93	printk(KERN_WARNING "%s: double free!\n", __FUNCTION__);
	94	}
	95
10083072 MM	96	int
	97	reserve_irq_vector (int vector)
	98	{
	99	int pos;
	100
	101	if (vector < IA64_FIRST_DEVICE_VECTOR \|\|
	102	vector > IA64_LAST_DEVICE_VECTOR)
	103	return -EINVAL;
	104
	105	pos = vector - IA64_FIRST_DEVICE_VECTOR;
	106	return test_and_set_bit(pos, ia64_vector_mask);
	107	}
	108
b6cf2583 EB	109	/*
	110	* Dynamic irq allocate and deallocation for MSI
	111	*/
	112	int create_irq(void)
	113	{
	114	int vector = assign_irq_vector(AUTO_ASSIGN);
	115
	116	if (vector >= 0)
	117	dynamic_irq_init(vector);
	118
	119	return vector;
	120	}
	121
	122	void destroy_irq(unsigned int irq)
	123	{
	124	dynamic_irq_cleanup(irq);
	125	free_irq_vector(irq);
	126	}
	127
1da177e4 LT	128	#ifdef CONFIG_SMP
	129	# define IS_RESCHEDULE(vec) (vec == IA64_IPI_RESCHEDULE)
	130	#else
	131	# define IS_RESCHEDULE(vec) (0)
	132	#endif
	133	/*
	134	* That's where the IVT branches when we get an external
	135	* interrupt. This branches to the correct hardware IRQ handler via
	136	* function ptr.
	137	*/
	138	void
	139	ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
	140	{
7d12e780	141	struct pt_regs *old_regs = set_irq_regs(regs);
1da177e4 LT	142	unsigned long saved_tpr;
	143
	144	#if IRQ_DEBUG
	145	{
	146	unsigned long bsp, sp;
	147
	148	/*
	149	* Note: if the interrupt happened while executing in
	150	* the context switch routine (ia64_switch_to), we may
	151	* get a spurious stack overflow here. This is
	152	* because the register and the memory stack are not
	153	* switched atomically.
	154	*/
	155	bsp = ia64_getreg(_IA64_REG_AR_BSP);
	156	sp = ia64_getreg(_IA64_REG_SP);
	157
	158	if ((sp - bsp) < 1024) {
	159	static unsigned char count;
	160	static long last_time;
	161
	162	if (jiffies - last_time > 5*HZ)
	163	count = 0;
	164	if (++count < 5) {
	165	last_time = jiffies;
	166	printk("ia64_handle_irq: DANGER: less than "
	167	"1KB of free stack space!!\n"
	168	"(bsp=0x%lx, sp=%lx)\n", bsp, sp);
	169	}
	170	}
	171	}
	172	#endif /* IRQ_DEBUG */
	173
	174	/*
	175	* Always set TPR to limit maximum interrupt nesting depth to
	176	* 16 (without this, it would be ~240, which could easily lead
	177	* to kernel stack overflows).
	178	*/
	179	irq_enter();
	180	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
	181	ia64_srlz_d();
	182	while (vector != IA64_SPURIOUS_INT_VECTOR) {
9b3377f9 JS	183	if (unlikely(IS_RESCHEDULE(vector)))
	184	kstat_this_cpu.irqs[vector]++;
	185	else {
1da177e4 LT	186	ia64_setreg(_IA64_REG_CR_TPR, vector);
	187	ia64_srlz_d();
	188
5fbb004a	189	generic_handle_irq(local_vector_to_irq(vector));
1da177e4 LT	190
	191	/*
	192	* Disable interrupts and send EOI:
	193	*/
	194	local_irq_disable();
	195	ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
	196	}
	197	ia64_eoi();
	198	vector = ia64_get_ivr();
	199	}
	200	/*
	201	* This must be done after the ia64_eoi(). For example, the keyboard softirq
	202	* handler needs to be able to wait for further keyboard interrupts, which can't
	203	* come through until ia64_eoi() has been done.
	204	*/
	205	irq_exit();
7d12e780	206	set_irq_regs(old_regs);
1da177e4 LT	207	}
	208
	209	#ifdef CONFIG_HOTPLUG_CPU
	210	/*
	211	* This function emulates a interrupt processing when a cpu is about to be
	212	* brought down.
	213	*/
	214	void ia64_process_pending_intr(void)
	215	{
	216	ia64_vector vector;
	217	unsigned long saved_tpr;
	218	extern unsigned int vectors_in_migration[NR_IRQS];
	219
	220	vector = ia64_get_ivr();
	221
	222	irq_enter();
	223	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
	224	ia64_srlz_d();
	225
	226	/*
	227	* Perform normal interrupt style processing
	228	*/
	229	while (vector != IA64_SPURIOUS_INT_VECTOR) {
9b3377f9 JS	230	if (unlikely(IS_RESCHEDULE(vector)))
	231	kstat_this_cpu.irqs[vector]++;
	232	else {
8c1addbc TL	233	struct pt_regs *old_regs = set_irq_regs(NULL);
8c1addbc TL	234
1da177e4 LT	235	ia64_setreg(_IA64_REG_CR_TPR, vector);
	236	ia64_srlz_d();
	237
	238	/*
	239	* Now try calling normal ia64_handle_irq as it would have got called
	240	* from a real intr handler. Try passing null for pt_regs, hopefully
	241	* it will work. I hope it works!.
	242	* Probably could shared code.
	243	*/
	244	vectors_in_migration[local_vector_to_irq(vector)]=0;
5fbb004a	245	generic_handle_irq(local_vector_to_irq(vector));
8c1addbc	246	set_irq_regs(old_regs);
1da177e4 LT	247
	248	/*
	249	* Disable interrupts and send EOI
	250	*/
	251	local_irq_disable();
	252	ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
	253	}
	254	ia64_eoi();
	255	vector = ia64_get_ivr();
	256	}
	257	irq_exit();
	258	}
	259	#endif
	260
	261
	262	#ifdef CONFIG_SMP
8c1addbc	263	extern irqreturn_t handle_IPI (int irq, void *dev_id);
1da177e4	264
9b3377f9 JS	265	static irqreturn_t dummy_handler (int irq, void *dev_id)
	266	{
	267	BUG();
	268	}
	269
1da177e4 LT	270	static struct irqaction ipi_irqaction = {
1da177e4 LT	271	.handler = handle_IPI,
121a4226	272	.flags = IRQF_DISABLED,
1da177e4 LT	273	.name = "IPI"
1da177e4 LT	274	};
9b3377f9 JS	275
	276	static struct irqaction resched_irqaction = {
	277	.handler = dummy_handler,
	278	.flags = SA_INTERRUPT,
	279	.name = "resched"
	280	};
1da177e4 LT	281	#endif
	282
	283	void
	284	register_percpu_irq (ia64_vector vec, struct irqaction *action)
	285	{
	286	irq_desc_t *desc;
	287	unsigned int irq;
	288
	289	for (irq = 0; irq < NR_IRQS; ++irq)
	290	if (irq_to_vector(irq) == vec) {
a8553acd	291	desc = irq_desc + irq;
1da177e4	292	desc->status \|= IRQ_PER_CPU;
d1bef4ed	293	desc->chip = &irq_type_ia64_lsapic;
1da177e4 LT	294	if (action)
	295	setup_irq(irq, action);
	296	}
	297	}
	298
	299	void __init
	300	init_IRQ (void)
	301	{
	302	register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
	303	#ifdef CONFIG_SMP
	304	register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
9b3377f9	305	register_percpu_irq(IA64_IPI_RESCHEDULE, &resched_irqaction);
1da177e4 LT	306	#endif
	307	#ifdef CONFIG_PERFMON
	308	pfm_init_percpu();
	309	#endif
	310	platform_irq_init();
	311	}
	312
	313	void
	314	ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
	315	{
	316	void __iomem *ipi_addr;
	317	unsigned long ipi_data;
	318	unsigned long phys_cpu_id;
	319
	320	#ifdef CONFIG_SMP
	321	phys_cpu_id = cpu_physical_id(cpu);
	322	#else
	323	phys_cpu_id = (ia64_getreg(_IA64_REG_CR_LID) >> 16) & 0xffff;
	324	#endif
	325
	326	/*
	327	* cpu number is in 8bit ID and 8bit EID
	328	*/
	329
	330	ipi_data = (delivery_mode << 8) \| (vector & 0xff);
	331	ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) \| ((redirect & 1) << 3));
	332
	333	writeq(ipi_data, ipi_addr);
	334	}