xref: /linux/arch/x86/kernel/irqinit.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
1 #include <linux/linkage.h>
2 #include <linux/errno.h>
3 #include <linux/signal.h>
4 #include <linux/sched.h>
5 #include <linux/ioport.h>
6 #include <linux/interrupt.h>
7 #include <linux/timex.h>
8 #include <linux/slab.h>
9 #include <linux/random.h>
10 #include <linux/kprobes.h>
11 #include <linux/init.h>
12 #include <linux/kernel_stat.h>
13 #include <linux/sysdev.h>
14 #include <linux/bitops.h>
15 #include <linux/acpi.h>
16 #include <linux/io.h>
17 #include <linux/delay.h>
18 
19 #include <asm/atomic.h>
20 #include <asm/system.h>
21 #include <asm/timer.h>
22 #include <asm/hw_irq.h>
23 #include <asm/pgtable.h>
24 #include <asm/desc.h>
25 #include <asm/apic.h>
26 #include <asm/setup.h>
27 #include <asm/i8259.h>
28 #include <asm/traps.h>
29 
30 /*
31  * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
32  * (these are usually mapped to vectors 0x30-0x3f)
33  */
34 
35 /*
36  * The IO-APIC gives us many more interrupt sources. Most of these
37  * are unused but an SMP system is supposed to have enough memory ...
38  * sometimes (mostly wrt. hw bugs) we get corrupted vectors all
39  * across the spectrum, so we really want to be prepared to get all
40  * of these. Plus, more powerful systems might have more than 64
41  * IO-APIC registers.
42  *
43  * (these are usually mapped into the 0x30-0xff vector range)
44  */
45 
46 #ifdef CONFIG_X86_32
47 /*
48  * Note that on a 486, we don't want to do a SIGFPE on an irq13
49  * as the irq is unreliable, and exception 16 works correctly
50  * (ie as explained in the intel literature). On a 386, you
51  * can't use exception 16 due to bad IBM design, so we have to
52  * rely on the less exact irq13.
53  *
54  * Careful.. Not only is IRQ13 unreliable, but it is also
55  * leads to races. IBM designers who came up with it should
56  * be shot.
57  */
58 
59 static irqreturn_t math_error_irq(int cpl, void *dev_id)
60 {
61 	outb(0, 0xF0);
62 	if (ignore_fpu_irq || !boot_cpu_data.hard_math)
63 		return IRQ_NONE;
64 	math_error((void __user *)get_irq_regs()->ip);
65 	return IRQ_HANDLED;
66 }
67 
68 /*
69  * New motherboards sometimes make IRQ 13 be a PCI interrupt,
70  * so allow interrupt sharing.
71  */
72 static struct irqaction fpu_irq = {
73 	.handler = math_error_irq,
74 	.name = "fpu",
75 };
76 #endif
77 
78 /*
79  * IRQ2 is cascade interrupt to second interrupt controller
80  */
81 static struct irqaction irq2 = {
82 	.handler = no_action,
83 	.name = "cascade",
84 };
85 
86 DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
87 	[0 ... IRQ0_VECTOR - 1] = -1,
88 	[IRQ0_VECTOR] = 0,
89 	[IRQ1_VECTOR] = 1,
90 	[IRQ2_VECTOR] = 2,
91 	[IRQ3_VECTOR] = 3,
92 	[IRQ4_VECTOR] = 4,
93 	[IRQ5_VECTOR] = 5,
94 	[IRQ6_VECTOR] = 6,
95 	[IRQ7_VECTOR] = 7,
96 	[IRQ8_VECTOR] = 8,
97 	[IRQ9_VECTOR] = 9,
98 	[IRQ10_VECTOR] = 10,
99 	[IRQ11_VECTOR] = 11,
100 	[IRQ12_VECTOR] = 12,
101 	[IRQ13_VECTOR] = 13,
102 	[IRQ14_VECTOR] = 14,
103 	[IRQ15_VECTOR] = 15,
104 	[IRQ15_VECTOR + 1 ... NR_VECTORS - 1] = -1
105 };
106 
107 int vector_used_by_percpu_irq(unsigned int vector)
108 {
109 	int cpu;
110 
111 	for_each_online_cpu(cpu) {
112 		if (per_cpu(vector_irq, cpu)[vector] != -1)
113 			return 1;
114 	}
115 
116 	return 0;
117 }
118 
119 static void __init init_ISA_irqs(void)
120 {
121 	int i;
122 
123 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
124 	init_bsp_APIC();
125 #endif
126 	init_8259A(0);
127 
128 	/*
129 	 * 16 old-style INTA-cycle interrupts:
130 	 */
131 	for (i = 0; i < NR_IRQS_LEGACY; i++) {
132 		struct irq_desc *desc = irq_to_desc(i);
133 
134 		desc->status = IRQ_DISABLED;
135 		desc->action = NULL;
136 		desc->depth = 1;
137 
138 		set_irq_chip_and_handler_name(i, &i8259A_chip,
139 					      handle_level_irq, "XT");
140 	}
141 }
142 
143 /* Overridden in paravirt.c */
144 void init_IRQ(void) __attribute__((weak, alias("native_init_IRQ")));
145 
146 static void __init smp_intr_init(void)
147 {
148 #ifdef CONFIG_SMP
149 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
150 	/*
151 	 * The reschedule interrupt is a CPU-to-CPU reschedule-helper
152 	 * IPI, driven by wakeup.
153 	 */
154 	alloc_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
155 
156 	/* IPIs for invalidation */
157 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+0, invalidate_interrupt0);
158 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+1, invalidate_interrupt1);
159 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+2, invalidate_interrupt2);
160 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+3, invalidate_interrupt3);
161 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+4, invalidate_interrupt4);
162 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+5, invalidate_interrupt5);
163 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+6, invalidate_interrupt6);
164 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+7, invalidate_interrupt7);
165 
166 	/* IPI for generic function call */
167 	alloc_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
168 
169 	/* IPI for generic single function call */
170 	alloc_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
171 			call_function_single_interrupt);
172 
173 	/* Low priority IPI to cleanup after moving an irq */
174 	set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
175 	set_bit(IRQ_MOVE_CLEANUP_VECTOR, used_vectors);
176 
177 	/* IPI used for rebooting/stopping */
178 	alloc_intr_gate(REBOOT_VECTOR, reboot_interrupt);
179 #endif
180 #endif /* CONFIG_SMP */
181 }
182 
183 static void __init apic_intr_init(void)
184 {
185 	smp_intr_init();
186 
187 #ifdef CONFIG_X86_THERMAL_VECTOR
188 	alloc_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
189 #endif
190 #ifdef CONFIG_X86_THRESHOLD
191 	alloc_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
192 #endif
193 #if defined(CONFIG_X86_NEW_MCE) && defined(CONFIG_X86_LOCAL_APIC)
194 	alloc_intr_gate(MCE_SELF_VECTOR, mce_self_interrupt);
195 #endif
196 
197 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
198 	/* self generated IPI for local APIC timer */
199 	alloc_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
200 
201 	/* generic IPI for platform specific use */
202 	alloc_intr_gate(GENERIC_INTERRUPT_VECTOR, generic_interrupt);
203 
204 	/* IPI vectors for APIC spurious and error interrupts */
205 	alloc_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
206 	alloc_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
207 
208 	/* Performance monitoring interrupts: */
209 # ifdef CONFIG_PERF_COUNTERS
210 	alloc_intr_gate(LOCAL_PENDING_VECTOR, perf_pending_interrupt);
211 # endif
212 
213 #endif
214 }
215 
216 /**
217  * x86_quirk_pre_intr_init - initialisation prior to setting up interrupt vectors
218  *
219  * Description:
220  *	Perform any necessary interrupt initialisation prior to setting up
221  *	the "ordinary" interrupt call gates.  For legacy reasons, the ISA
222  *	interrupts should be initialised here if the machine emulates a PC
223  *	in any way.
224  **/
225 static void __init x86_quirk_pre_intr_init(void)
226 {
227 #ifdef CONFIG_X86_32
228 	if (x86_quirks->arch_pre_intr_init) {
229 		if (x86_quirks->arch_pre_intr_init())
230 			return;
231 	}
232 #endif
233 	init_ISA_irqs();
234 }
235 
236 void __init native_init_IRQ(void)
237 {
238 	int i;
239 
240 	/* Execute any quirks before the call gates are initialised: */
241 	x86_quirk_pre_intr_init();
242 
243 	apic_intr_init();
244 
245 	/*
246 	 * Cover the whole vector space, no vector can escape
247 	 * us. (some of these will be overridden and become
248 	 * 'special' SMP interrupts)
249 	 */
250 	for (i = FIRST_EXTERNAL_VECTOR; i < NR_VECTORS; i++) {
251 		/* IA32_SYSCALL_VECTOR could be used in trap_init already. */
252 		if (!test_bit(i, used_vectors))
253 			set_intr_gate(i, interrupt[i-FIRST_EXTERNAL_VECTOR]);
254 	}
255 
256 	if (!acpi_ioapic)
257 		setup_irq(2, &irq2);
258 
259 #ifdef CONFIG_X86_32
260 	/*
261 	 * Call quirks after call gates are initialised (usually add in
262 	 * the architecture specific gates):
263 	 */
264 	x86_quirk_intr_init();
265 
266 	/*
267 	 * External FPU? Set up irq13 if so, for
268 	 * original braindamaged IBM FERR coupling.
269 	 */
270 	if (boot_cpu_data.hard_math && !cpu_has_fpu)
271 		setup_irq(FPU_IRQ, &fpu_irq);
272 
273 	irq_ctx_init(smp_processor_id());
274 #endif
275 }
276