aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/irqinit.c
blob: f3be5e974275cb0c92a60f980233547c058fcac2 (plain) (blame)
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
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
#include <linux/linkage.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/timex.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/init.h>
#include <linux/kernel_stat.h>
#include <linux/sysdev.h>
#include <linux/bitops.h>
#include <linux/acpi.h>
#include <linux/io.h>
#include <linux/delay.h>

#include <asm/atomic.h>
#include <asm/system.h>
#include <asm/timer.h>
#include <asm/hw_irq.h>
#include <asm/pgtable.h>
#include <asm/desc.h>
#include <asm/apic.h>
#include <asm/setup.h>
#include <asm/i8259.h>
#include <asm/traps.h>

/*
 * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
 * (these are usually mapped to vectors 0x30-0x3f)
 */

/*
 * The IO-APIC gives us many more interrupt sources. Most of these
 * are unused but an SMP system is supposed to have enough memory ...
 * sometimes (mostly wrt. hw bugs) we get corrupted vectors all
 * across the spectrum, so we really want to be prepared to get all
 * of these. Plus, more powerful systems might have more than 64
 * IO-APIC registers.
 *
 * (these are usually mapped into the 0x30-0xff vector range)
 */

#ifdef CONFIG_X86_32
/*
 * Note that on a 486, we don't want to do a SIGFPE on an irq13
 * as the irq is unreliable, and exception 16 works correctly
 * (ie as explained in the intel literature). On a 386, you
 * can't use exception 16 due to bad IBM design, so we have to
 * rely on the less exact irq13.
 *
 * Careful.. Not only is IRQ13 unreliable, but it is also
 * leads to races. IBM designers who came up with it should
 * be shot.
 */

static irqreturn_t math_error_irq(int cpl, void *dev_id)
{
	outb(0, 0xF0);
	if (ignore_fpu_irq || !boot_cpu_data.hard_math)
		return IRQ_NONE;
	math_error((void __user *)get_irq_regs()->ip);
	return IRQ_HANDLED;
}

/*
 * New motherboards sometimes make IRQ 13 be a PCI interrupt,
 * so allow interrupt sharing.
 */
static struct irqaction fpu_irq = {
	.handler = math_error_irq,
	.name = "fpu",
};
#endif

/*
 * IRQ2 is cascade interrupt to second interrupt controller
 */
static struct irqaction irq2 = {
	.handler = no_action,
	.name = "cascade",
};

DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
	[0 ... IRQ0_VECTOR - 1] = -1,
	[IRQ0_VECTOR] = 0,
	[IRQ1_VECTOR] = 1,
	[IRQ2_VECTOR] = 2,
	[IRQ3_VECTOR] = 3,
	[IRQ4_VECTOR] = 4,
	[IRQ5_VECTOR] = 5,
	[IRQ6_VECTOR] = 6,
	[IRQ7_VECTOR] = 7,
	[IRQ8_VECTOR] = 8,
	[IRQ9_VECTOR] = 9,
	[IRQ10_VECTOR] = 10,
	[IRQ11_VECTOR] = 11,
	[IRQ12_VECTOR] = 12,
	[IRQ13_VECTOR] = 13,
	[IRQ14_VECTOR] = 14,
	[IRQ15_VECTOR] = 15,
	[IRQ15_VECTOR + 1 ... NR_VECTORS - 1] = -1
};

int vector_used_by_percpu_irq(unsigned int vector)
{
	int cpu;

	for_each_online_cpu(cpu) {
		if (per_cpu(vector_irq, cpu)[vector] != -1)
			return 1;
	}

	return 0;
}

static void __init init_ISA_irqs(void)
{
	int i;

#if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
	init_bsp_APIC();
#endif
	init_8259A(0);

	/*
	 * 16 old-style INTA-cycle interrupts:
	 */
	for (i = 0; i < NR_IRQS_LEGACY; i++) {
		struct irq_desc *desc = irq_to_desc(i);

		desc->status = IRQ_DISABLED;
		desc->action = NULL;
		desc->depth = 1;

		set_irq_chip_and_handler_name(i, &i8259A_chip,
					      handle_level_irq, "XT");
	}
}

/* Overridden in paravirt.c */
void init_IRQ(void) __attribute__((weak, alias("native_init_IRQ")));

static void __init smp_intr_init(void)
{
#ifdef CONFIG_SMP
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
	/*
	 * The reschedule interrupt is a CPU-to-CPU reschedule-helper
	 * IPI, driven by wakeup.
	 */
	alloc_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);

	/* IPIs for invalidation */
	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+0, invalidate_interrupt0);
	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+1, invalidate_interrupt1);
	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+2, invalidate_interrupt2);
	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+3, invalidate_interrupt3);
	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+4, invalidate_interrupt4);
	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+5, invalidate_interrupt5);
	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+6, invalidate_interrupt6);
	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+7, invalidate_interrupt7);

	/* IPI for generic function call */
	alloc_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);

	/* IPI for generic single function call */
	alloc_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
			call_function_single_interrupt);

	/* Low priority IPI to cleanup after moving an irq */
	set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
	set_bit(IRQ_MOVE_CLEANUP_VECTOR, used_vectors);
#endif
#endif /* CONFIG_SMP */
}

static void __init apic_intr_init(void)
{
	smp_intr_init();

#ifdef CONFIG_X86_64
	alloc_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
	alloc_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
#endif

#if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
	/* self generated IPI for local APIC timer */
	alloc_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);

	/* generic IPI for platform specific use */
	alloc_intr_gate(GENERIC_INTERRUPT_VECTOR, generic_interrupt);

	/* IPI vectors for APIC spurious and error interrupts */
	alloc_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
	alloc_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
#endif

#ifdef CONFIG_X86_32
#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_MCE_P4THERMAL)
	/* thermal monitor LVT interrupt */
	alloc_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
#endif
#endif
}

#ifdef CONFIG_X86_32
/**
 * x86_quirk_pre_intr_init - initialisation prior to setting up interrupt vectors
 *
 * Description:
 *	Perform any necessary interrupt initialisation prior to setting up
 *	the "ordinary" interrupt call gates.  For legacy reasons, the ISA
 *	interrupts should be initialised here if the machine emulates a PC
 *	in any way.
 **/
static void __init x86_quirk_pre_intr_init(void)
{
	if (x86_quirks->arch_pre_intr_init) {
		if (x86_quirks->arch_pre_intr_init())
			return;
	}
	init_ISA_irqs();
}
#endif

void __init native_init_IRQ(void)
{
	int i;

#ifdef CONFIG_X86_32
	/* Execute any quirks before the call gates are initialised: */
	x86_quirk_pre_intr_init();
#else
	init_ISA_irqs();
#endif

	/*
	 * Cover the whole vector space, no vector can escape
	 * us. (some of these will be overridden and become
	 * 'special' SMP interrupts)
	 */
	for (i = FIRST_EXTERNAL_VECTOR; i < NR_VECTORS; i++) {
#ifdef CONFIG_X86_32
		/* SYSCALL_VECTOR was reserved in trap_init. */
		if (i != SYSCALL_VECTOR)
			set_intr_gate(i, interrupt[i-FIRST_EXTERNAL_VECTOR]);
#else
		/* IA32_SYSCALL_VECTOR was reserved in trap_init. */
		if (i != IA32_SYSCALL_VECTOR)
			set_intr_gate(i, interrupt[i-FIRST_EXTERNAL_VECTOR]);
#endif
	}

	apic_intr_init();

	if (!acpi_ioapic)
		setup_irq(2, &irq2);

#ifdef CONFIG_X86_32
	/*
	 * Call quirks after call gates are initialised (usually add in
	 * the architecture specific gates):
	 */
	x86_quirk_intr_init();

	/*
	 * External FPU? Set up irq13 if so, for
	 * original braindamaged IBM FERR coupling.
	 */
	if (boot_cpu_data.hard_math && !cpu_has_fpu)
		setup_irq(FPU_IRQ, &fpu_irq);

	irq_ctx_init(smp_processor_id());
#endif
}