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/random.h>
9 #include <linux/kprobes.h>
10 #include <linux/init.h>
11 #include <linux/kernel_stat.h>
12 #include <linux/device.h>
13 #include <linux/bitops.h>
14 #include <linux/acpi.h>
15 #include <linux/io.h>
16 #include <linux/delay.h>
17 
18 #include <linux/atomic.h>
19 #include <asm/timer.h>
20 #include <asm/hw_irq.h>
21 #include <asm/pgtable.h>
22 #include <asm/desc.h>
23 #include <asm/apic.h>
24 #include <asm/setup.h>
25 #include <asm/i8259.h>
26 #include <asm/traps.h>
27 #include <asm/prom.h>
28 
29 /*
30  * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
31  * (these are usually mapped to vectors 0x30-0x3f)
32  */
33 
34 /*
35  * The IO-APIC gives us many more interrupt sources. Most of these
36  * are unused but an SMP system is supposed to have enough memory ...
37  * sometimes (mostly wrt. hw bugs) we get corrupted vectors all
38  * across the spectrum, so we really want to be prepared to get all
39  * of these. Plus, more powerful systems might have more than 64
40  * IO-APIC registers.
41  *
42  * (these are usually mapped into the 0x30-0xff vector range)
43  */
44 
45 #ifdef CONFIG_X86_32
46 /*
47  * Note that on a 486, we don't want to do a SIGFPE on an irq13
48  * as the irq is unreliable, and exception 16 works correctly
49  * (ie as explained in the intel literature). On a 386, you
50  * can't use exception 16 due to bad IBM design, so we have to
51  * rely on the less exact irq13.
52  *
53  * Careful.. Not only is IRQ13 unreliable, but it is also
54  * leads to races. IBM designers who came up with it should
55  * be shot.
56  */
57 
math_error_irq(int cpl,void * dev_id)58 static irqreturn_t math_error_irq(int cpl, void *dev_id)
59 {
60 	outb(0, 0xF0);
61 	if (ignore_fpu_irq || !boot_cpu_data.hard_math)
62 		return IRQ_NONE;
63 	math_error(get_irq_regs(), 0, X86_TRAP_MF);
64 	return IRQ_HANDLED;
65 }
66 
67 /*
68  * New motherboards sometimes make IRQ 13 be a PCI interrupt,
69  * so allow interrupt sharing.
70  */
71 static struct irqaction fpu_irq = {
72 	.handler = math_error_irq,
73 	.name = "fpu",
74 	.flags = IRQF_NO_THREAD,
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 	.flags = IRQF_NO_THREAD,
85 };
86 
87 DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
88 	[0 ... NR_VECTORS - 1] = -1,
89 };
90 
vector_used_by_percpu_irq(unsigned int vector)91 int vector_used_by_percpu_irq(unsigned int vector)
92 {
93 	int cpu;
94 
95 	for_each_online_cpu(cpu) {
96 		if (per_cpu(vector_irq, cpu)[vector] != -1)
97 			return 1;
98 	}
99 
100 	return 0;
101 }
102 
init_ISA_irqs(void)103 void __init init_ISA_irqs(void)
104 {
105 	struct irq_chip *chip = legacy_pic->chip;
106 	const char *name = chip->name;
107 	int i;
108 
109 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
110 	init_bsp_APIC();
111 #endif
112 	legacy_pic->init(0);
113 
114 	for (i = 0; i < legacy_pic->nr_legacy_irqs; i++)
115 		irq_set_chip_and_handler_name(i, chip, handle_level_irq, name);
116 }
117 
init_IRQ(void)118 void __init init_IRQ(void)
119 {
120 	int i;
121 
122 	/*
123 	 * We probably need a better place for this, but it works for
124 	 * now ...
125 	 */
126 	x86_add_irq_domains();
127 
128 	/*
129 	 * On cpu 0, Assign IRQ0_VECTOR..IRQ15_VECTOR's to IRQ 0..15.
130 	 * If these IRQ's are handled by legacy interrupt-controllers like PIC,
131 	 * then this configuration will likely be static after the boot. If
132 	 * these IRQ's are handled by more mordern controllers like IO-APIC,
133 	 * then this vector space can be freed and re-used dynamically as the
134 	 * irq's migrate etc.
135 	 */
136 	for (i = 0; i < legacy_pic->nr_legacy_irqs; i++)
137 		per_cpu(vector_irq, 0)[IRQ0_VECTOR + i] = i;
138 
139 	x86_init.irqs.intr_init();
140 }
141 
142 /*
143  * Setup the vector to irq mappings.
144  */
setup_vector_irq(int cpu)145 void setup_vector_irq(int cpu)
146 {
147 #ifndef CONFIG_X86_IO_APIC
148 	int irq;
149 
150 	/*
151 	 * On most of the platforms, legacy PIC delivers the interrupts on the
152 	 * boot cpu. But there are certain platforms where PIC interrupts are
153 	 * delivered to multiple cpu's. If the legacy IRQ is handled by the
154 	 * legacy PIC, for the new cpu that is coming online, setup the static
155 	 * legacy vector to irq mapping:
156 	 */
157 	for (irq = 0; irq < legacy_pic->nr_legacy_irqs; irq++)
158 		per_cpu(vector_irq, cpu)[IRQ0_VECTOR + irq] = irq;
159 #endif
160 
161 	__setup_vector_irq(cpu);
162 }
163 
smp_intr_init(void)164 static void __init smp_intr_init(void)
165 {
166 #ifdef CONFIG_SMP
167 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
168 	/*
169 	 * The reschedule interrupt is a CPU-to-CPU reschedule-helper
170 	 * IPI, driven by wakeup.
171 	 */
172 	alloc_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
173 
174 	/* IPIs for invalidation */
175 #define ALLOC_INVTLB_VEC(NR) \
176 	alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+NR, \
177 		invalidate_interrupt##NR)
178 
179 	switch (NUM_INVALIDATE_TLB_VECTORS) {
180 	default:
181 		ALLOC_INVTLB_VEC(31);
182 	case 31:
183 		ALLOC_INVTLB_VEC(30);
184 	case 30:
185 		ALLOC_INVTLB_VEC(29);
186 	case 29:
187 		ALLOC_INVTLB_VEC(28);
188 	case 28:
189 		ALLOC_INVTLB_VEC(27);
190 	case 27:
191 		ALLOC_INVTLB_VEC(26);
192 	case 26:
193 		ALLOC_INVTLB_VEC(25);
194 	case 25:
195 		ALLOC_INVTLB_VEC(24);
196 	case 24:
197 		ALLOC_INVTLB_VEC(23);
198 	case 23:
199 		ALLOC_INVTLB_VEC(22);
200 	case 22:
201 		ALLOC_INVTLB_VEC(21);
202 	case 21:
203 		ALLOC_INVTLB_VEC(20);
204 	case 20:
205 		ALLOC_INVTLB_VEC(19);
206 	case 19:
207 		ALLOC_INVTLB_VEC(18);
208 	case 18:
209 		ALLOC_INVTLB_VEC(17);
210 	case 17:
211 		ALLOC_INVTLB_VEC(16);
212 	case 16:
213 		ALLOC_INVTLB_VEC(15);
214 	case 15:
215 		ALLOC_INVTLB_VEC(14);
216 	case 14:
217 		ALLOC_INVTLB_VEC(13);
218 	case 13:
219 		ALLOC_INVTLB_VEC(12);
220 	case 12:
221 		ALLOC_INVTLB_VEC(11);
222 	case 11:
223 		ALLOC_INVTLB_VEC(10);
224 	case 10:
225 		ALLOC_INVTLB_VEC(9);
226 	case 9:
227 		ALLOC_INVTLB_VEC(8);
228 	case 8:
229 		ALLOC_INVTLB_VEC(7);
230 	case 7:
231 		ALLOC_INVTLB_VEC(6);
232 	case 6:
233 		ALLOC_INVTLB_VEC(5);
234 	case 5:
235 		ALLOC_INVTLB_VEC(4);
236 	case 4:
237 		ALLOC_INVTLB_VEC(3);
238 	case 3:
239 		ALLOC_INVTLB_VEC(2);
240 	case 2:
241 		ALLOC_INVTLB_VEC(1);
242 	case 1:
243 		ALLOC_INVTLB_VEC(0);
244 		break;
245 	}
246 
247 	/* IPI for generic function call */
248 	alloc_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
249 
250 	/* IPI for generic single function call */
251 	alloc_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
252 			call_function_single_interrupt);
253 
254 	/* Low priority IPI to cleanup after moving an irq */
255 	set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
256 	set_bit(IRQ_MOVE_CLEANUP_VECTOR, used_vectors);
257 
258 	/* IPI used for rebooting/stopping */
259 	alloc_intr_gate(REBOOT_VECTOR, reboot_interrupt);
260 #endif
261 #endif /* CONFIG_SMP */
262 }
263 
apic_intr_init(void)264 static void __init apic_intr_init(void)
265 {
266 	smp_intr_init();
267 
268 #ifdef CONFIG_X86_THERMAL_VECTOR
269 	alloc_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
270 #endif
271 #ifdef CONFIG_X86_MCE_THRESHOLD
272 	alloc_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
273 #endif
274 
275 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
276 	/* self generated IPI for local APIC timer */
277 	alloc_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
278 
279 	/* IPI for X86 platform specific use */
280 	alloc_intr_gate(X86_PLATFORM_IPI_VECTOR, x86_platform_ipi);
281 
282 	/* IPI vectors for APIC spurious and error interrupts */
283 	alloc_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
284 	alloc_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
285 
286 	/* IRQ work interrupts: */
287 # ifdef CONFIG_IRQ_WORK
288 	alloc_intr_gate(IRQ_WORK_VECTOR, irq_work_interrupt);
289 # endif
290 
291 #endif
292 }
293 
native_init_IRQ(void)294 void __init native_init_IRQ(void)
295 {
296 	int i;
297 
298 	/* Execute any quirks before the call gates are initialised: */
299 	x86_init.irqs.pre_vector_init();
300 
301 	apic_intr_init();
302 
303 	/*
304 	 * Cover the whole vector space, no vector can escape
305 	 * us. (some of these will be overridden and become
306 	 * 'special' SMP interrupts)
307 	 */
308 	i = FIRST_EXTERNAL_VECTOR;
309 	for_each_clear_bit_from(i, used_vectors, NR_VECTORS) {
310 		/* IA32_SYSCALL_VECTOR could be used in trap_init already. */
311 		set_intr_gate(i, interrupt[i - FIRST_EXTERNAL_VECTOR]);
312 	}
313 
314 	if (!acpi_ioapic && !of_ioapic)
315 		setup_irq(2, &irq2);
316 
317 #ifdef CONFIG_X86_32
318 	/*
319 	 * External FPU? Set up irq13 if so, for
320 	 * original braindamaged IBM FERR coupling.
321 	 */
322 	if (boot_cpu_data.hard_math && !cpu_has_fpu)
323 		setup_irq(FPU_IRQ, &fpu_irq);
324 
325 	irq_ctx_init(smp_processor_id());
326 #endif
327 }
328