summaryrefslogtreecommitdiffstats
path: root/arch/ia64/kernel/irq_ia64.c
blob: 155ee66b7525ff8e8ff57b6f23674735d8387507 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
/*
 * linux/arch/ia64/kernel/irq.c
 *
 * Copyright (C) 1998-2000 Hewlett-Packard Co
 * Copyright (C) 1998, 1999 Stephane Eranian <eranian@hpl.hp.com>
 * Copyright (C) 1999-2000 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.
 */

#include <linux/config.h>

#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/kernel_stat.h>
#include <linux/malloc.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 <asm/bitops.h>
#include <asm/delay.h>
#include <asm/io.h>
#include <asm/hw_irq.h>
#include <asm/machvec.h>
#include <asm/pgtable.h>
#include <asm/system.h>

#define IRQ_DEBUG	0

/* default base addr of IPI table */
unsigned long ipi_base_addr = (__IA64_UNCACHED_OFFSET | 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
};

int
ia64_alloc_irq (void)
{
	static int next_irq = FIRST_DEVICE_IRQ;

	if (next_irq > LAST_DEVICE_IRQ)
		/* XXX could look for sharable vectors instead of panic'ing... */
		panic("ia64_alloc_irq: out of interrupt vectors!");
	return next_irq++;
}

/*
 * 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 (unsigned long vector, struct pt_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.
		 */
		asm ("mov %0=ar.bsp" : "=r"(bsp));
		asm ("mov %0=sp" : "=r"(sp));

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

			if (count > 5 && 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).
	 */
	saved_tpr = ia64_get_tpr();
	ia64_srlz_d();
	do {
		if (vector >= NR_IRQS) {
			printk("handle_irq: invalid vector %lu\n", vector);
			ia64_set_tpr(saved_tpr);
			ia64_srlz_d();
			return;
		}
		ia64_set_tpr(vector);
		ia64_srlz_d();

		if ((irq_desc[vector].status & IRQ_PER_CPU) != 0)
			do_IRQ_per_cpu(vector, regs);
		else
			do_IRQ(vector, regs);

		/*
		 * Disable interrupts and send EOI:
		 */
		local_irq_disable();
		ia64_set_tpr(saved_tpr);
		ia64_eoi();
		vector = ia64_get_ivr();
	} while (vector != IA64_SPURIOUS_INT);
}

#ifdef CONFIG_SMP

extern void handle_IPI (int irq, void *dev_id, struct pt_regs *regs);

static struct irqaction ipi_irqaction = {
	handler:	handle_IPI,
	flags:		SA_INTERRUPT,
	name:		"IPI"
};
#endif

void __init
init_IRQ (void)
{
	/*
	 * Disable all local interrupts
	 */
	ia64_set_itv(0, 1);
	ia64_set_lrr0(0, 1);
	ia64_set_lrr1(0, 1);

	irq_desc[IA64_SPURIOUS_INT].handler = &irq_type_ia64_sapic;
#ifdef CONFIG_SMP
	/* 
	 * Configure the IPI vector and handler
	 */
	irq_desc[IPI_IRQ].status |= IRQ_PER_CPU;
	irq_desc[IPI_IRQ].handler = &irq_type_ia64_sapic;
	setup_irq(IPI_IRQ, &ipi_irqaction);
#endif

	ia64_set_pmv(1 << 16);
	ia64_set_cmcv(CMC_IRQ);			/* XXX fix me */

	platform_irq_init();

	/* clear TPR to enable all interrupt classes: */
	ia64_set_tpr(0);
}

void
ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
{
	unsigned long 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_get_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);
}