aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/i8259_64.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/i8259_64.c')
-rw-r--r--arch/x86/kernel/i8259_64.c544
1 files changed, 544 insertions, 0 deletions
diff --git a/arch/x86/kernel/i8259_64.c b/arch/x86/kernel/i8259_64.c
new file mode 100644
index 000000000000..948cae646099
--- /dev/null
+++ b/arch/x86/kernel/i8259_64.c
@@ -0,0 +1,544 @@
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/init.h>
11#include <linux/kernel_stat.h>
12#include <linux/sysdev.h>
13#include <linux/bitops.h>
14
15#include <asm/acpi.h>
16#include <asm/atomic.h>
17#include <asm/system.h>
18#include <asm/io.h>
19#include <asm/hw_irq.h>
20#include <asm/pgtable.h>
21#include <asm/delay.h>
22#include <asm/desc.h>
23#include <asm/apic.h>
24
25/*
26 * Common place to define all x86 IRQ vectors
27 *
28 * This builds up the IRQ handler stubs using some ugly macros in irq.h
29 *
30 * These macros create the low-level assembly IRQ routines that save
31 * register context and call do_IRQ(). do_IRQ() then does all the
32 * operations that are needed to keep the AT (or SMP IOAPIC)
33 * interrupt-controller happy.
34 */
35
36#define BI(x,y) \
37 BUILD_IRQ(x##y)
38
39#define BUILD_16_IRQS(x) \
40 BI(x,0) BI(x,1) BI(x,2) BI(x,3) \
41 BI(x,4) BI(x,5) BI(x,6) BI(x,7) \
42 BI(x,8) BI(x,9) BI(x,a) BI(x,b) \
43 BI(x,c) BI(x,d) BI(x,e) BI(x,f)
44
45/*
46 * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
47 * (these are usually mapped to vectors 0x30-0x3f)
48 */
49
50/*
51 * The IO-APIC gives us many more interrupt sources. Most of these
52 * are unused but an SMP system is supposed to have enough memory ...
53 * sometimes (mostly wrt. hw bugs) we get corrupted vectors all
54 * across the spectrum, so we really want to be prepared to get all
55 * of these. Plus, more powerful systems might have more than 64
56 * IO-APIC registers.
57 *
58 * (these are usually mapped into the 0x30-0xff vector range)
59 */
60 BUILD_16_IRQS(0x2) BUILD_16_IRQS(0x3)
61BUILD_16_IRQS(0x4) BUILD_16_IRQS(0x5) BUILD_16_IRQS(0x6) BUILD_16_IRQS(0x7)
62BUILD_16_IRQS(0x8) BUILD_16_IRQS(0x9) BUILD_16_IRQS(0xa) BUILD_16_IRQS(0xb)
63BUILD_16_IRQS(0xc) BUILD_16_IRQS(0xd) BUILD_16_IRQS(0xe) BUILD_16_IRQS(0xf)
64
65#undef BUILD_16_IRQS
66#undef BI
67
68
69#define IRQ(x,y) \
70 IRQ##x##y##_interrupt
71
72#define IRQLIST_16(x) \
73 IRQ(x,0), IRQ(x,1), IRQ(x,2), IRQ(x,3), \
74 IRQ(x,4), IRQ(x,5), IRQ(x,6), IRQ(x,7), \
75 IRQ(x,8), IRQ(x,9), IRQ(x,a), IRQ(x,b), \
76 IRQ(x,c), IRQ(x,d), IRQ(x,e), IRQ(x,f)
77
78/* for the irq vectors */
79static void (*interrupt[NR_VECTORS - FIRST_EXTERNAL_VECTOR])(void) = {
80 IRQLIST_16(0x2), IRQLIST_16(0x3),
81 IRQLIST_16(0x4), IRQLIST_16(0x5), IRQLIST_16(0x6), IRQLIST_16(0x7),
82 IRQLIST_16(0x8), IRQLIST_16(0x9), IRQLIST_16(0xa), IRQLIST_16(0xb),
83 IRQLIST_16(0xc), IRQLIST_16(0xd), IRQLIST_16(0xe), IRQLIST_16(0xf)
84};
85
86#undef IRQ
87#undef IRQLIST_16
88
89/*
90 * This is the 'legacy' 8259A Programmable Interrupt Controller,
91 * present in the majority of PC/AT boxes.
92 * plus some generic x86 specific things if generic specifics makes
93 * any sense at all.
94 * this file should become arch/i386/kernel/irq.c when the old irq.c
95 * moves to arch independent land
96 */
97
98static int i8259A_auto_eoi;
99DEFINE_SPINLOCK(i8259A_lock);
100static void mask_and_ack_8259A(unsigned int);
101
102static struct irq_chip i8259A_chip = {
103 .name = "XT-PIC",
104 .mask = disable_8259A_irq,
105 .disable = disable_8259A_irq,
106 .unmask = enable_8259A_irq,
107 .mask_ack = mask_and_ack_8259A,
108};
109
110/*
111 * 8259A PIC functions to handle ISA devices:
112 */
113
114/*
115 * This contains the irq mask for both 8259A irq controllers,
116 */
117static unsigned int cached_irq_mask = 0xffff;
118
119#define __byte(x,y) (((unsigned char *)&(y))[x])
120#define cached_21 (__byte(0,cached_irq_mask))
121#define cached_A1 (__byte(1,cached_irq_mask))
122
123/*
124 * Not all IRQs can be routed through the IO-APIC, eg. on certain (older)
125 * boards the timer interrupt is not really connected to any IO-APIC pin,
126 * it's fed to the master 8259A's IR0 line only.
127 *
128 * Any '1' bit in this mask means the IRQ is routed through the IO-APIC.
129 * this 'mixed mode' IRQ handling costs nothing because it's only used
130 * at IRQ setup time.
131 */
132unsigned long io_apic_irqs;
133
134void disable_8259A_irq(unsigned int irq)
135{
136 unsigned int mask = 1 << irq;
137 unsigned long flags;
138
139 spin_lock_irqsave(&i8259A_lock, flags);
140 cached_irq_mask |= mask;
141 if (irq & 8)
142 outb(cached_A1,0xA1);
143 else
144 outb(cached_21,0x21);
145 spin_unlock_irqrestore(&i8259A_lock, flags);
146}
147
148void enable_8259A_irq(unsigned int irq)
149{
150 unsigned int mask = ~(1 << irq);
151 unsigned long flags;
152
153 spin_lock_irqsave(&i8259A_lock, flags);
154 cached_irq_mask &= mask;
155 if (irq & 8)
156 outb(cached_A1,0xA1);
157 else
158 outb(cached_21,0x21);
159 spin_unlock_irqrestore(&i8259A_lock, flags);
160}
161
162int i8259A_irq_pending(unsigned int irq)
163{
164 unsigned int mask = 1<<irq;
165 unsigned long flags;
166 int ret;
167
168 spin_lock_irqsave(&i8259A_lock, flags);
169 if (irq < 8)
170 ret = inb(0x20) & mask;
171 else
172 ret = inb(0xA0) & (mask >> 8);
173 spin_unlock_irqrestore(&i8259A_lock, flags);
174
175 return ret;
176}
177
178void make_8259A_irq(unsigned int irq)
179{
180 disable_irq_nosync(irq);
181 io_apic_irqs &= ~(1<<irq);
182 set_irq_chip_and_handler_name(irq, &i8259A_chip, handle_level_irq,
183 "XT");
184 enable_irq(irq);
185}
186
187/*
188 * This function assumes to be called rarely. Switching between
189 * 8259A registers is slow.
190 * This has to be protected by the irq controller spinlock
191 * before being called.
192 */
193static inline int i8259A_irq_real(unsigned int irq)
194{
195 int value;
196 int irqmask = 1<<irq;
197
198 if (irq < 8) {
199 outb(0x0B,0x20); /* ISR register */
200 value = inb(0x20) & irqmask;
201 outb(0x0A,0x20); /* back to the IRR register */
202 return value;
203 }
204 outb(0x0B,0xA0); /* ISR register */
205 value = inb(0xA0) & (irqmask >> 8);
206 outb(0x0A,0xA0); /* back to the IRR register */
207 return value;
208}
209
210/*
211 * Careful! The 8259A is a fragile beast, it pretty
212 * much _has_ to be done exactly like this (mask it
213 * first, _then_ send the EOI, and the order of EOI
214 * to the two 8259s is important!
215 */
216static void mask_and_ack_8259A(unsigned int irq)
217{
218 unsigned int irqmask = 1 << irq;
219 unsigned long flags;
220
221 spin_lock_irqsave(&i8259A_lock, flags);
222 /*
223 * Lightweight spurious IRQ detection. We do not want
224 * to overdo spurious IRQ handling - it's usually a sign
225 * of hardware problems, so we only do the checks we can
226 * do without slowing down good hardware unnecessarily.
227 *
228 * Note that IRQ7 and IRQ15 (the two spurious IRQs
229 * usually resulting from the 8259A-1|2 PICs) occur
230 * even if the IRQ is masked in the 8259A. Thus we
231 * can check spurious 8259A IRQs without doing the
232 * quite slow i8259A_irq_real() call for every IRQ.
233 * This does not cover 100% of spurious interrupts,
234 * but should be enough to warn the user that there
235 * is something bad going on ...
236 */
237 if (cached_irq_mask & irqmask)
238 goto spurious_8259A_irq;
239 cached_irq_mask |= irqmask;
240
241handle_real_irq:
242 if (irq & 8) {
243 inb(0xA1); /* DUMMY - (do we need this?) */
244 outb(cached_A1,0xA1);
245 outb(0x60+(irq&7),0xA0);/* 'Specific EOI' to slave */
246 outb(0x62,0x20); /* 'Specific EOI' to master-IRQ2 */
247 } else {
248 inb(0x21); /* DUMMY - (do we need this?) */
249 outb(cached_21,0x21);
250 outb(0x60+irq,0x20); /* 'Specific EOI' to master */
251 }
252 spin_unlock_irqrestore(&i8259A_lock, flags);
253 return;
254
255spurious_8259A_irq:
256 /*
257 * this is the slow path - should happen rarely.
258 */
259 if (i8259A_irq_real(irq))
260 /*
261 * oops, the IRQ _is_ in service according to the
262 * 8259A - not spurious, go handle it.
263 */
264 goto handle_real_irq;
265
266 {
267 static int spurious_irq_mask;
268 /*
269 * At this point we can be sure the IRQ is spurious,
270 * lets ACK and report it. [once per IRQ]
271 */
272 if (!(spurious_irq_mask & irqmask)) {
273 printk(KERN_DEBUG "spurious 8259A interrupt: IRQ%d.\n", irq);
274 spurious_irq_mask |= irqmask;
275 }
276 atomic_inc(&irq_err_count);
277 /*
278 * Theoretically we do not have to handle this IRQ,
279 * but in Linux this does not cause problems and is
280 * simpler for us.
281 */
282 goto handle_real_irq;
283 }
284}
285
286void init_8259A(int auto_eoi)
287{
288 unsigned long flags;
289
290 i8259A_auto_eoi = auto_eoi;
291
292 spin_lock_irqsave(&i8259A_lock, flags);
293
294 outb(0xff, 0x21); /* mask all of 8259A-1 */
295 outb(0xff, 0xA1); /* mask all of 8259A-2 */
296
297 /*
298 * outb_p - this has to work on a wide range of PC hardware.
299 */
300 outb_p(0x11, 0x20); /* ICW1: select 8259A-1 init */
301 outb_p(IRQ0_VECTOR, 0x21); /* ICW2: 8259A-1 IR0-7 mapped to 0x30-0x37 */
302 outb_p(0x04, 0x21); /* 8259A-1 (the master) has a slave on IR2 */
303 if (auto_eoi)
304 outb_p(0x03, 0x21); /* master does Auto EOI */
305 else
306 outb_p(0x01, 0x21); /* master expects normal EOI */
307
308 outb_p(0x11, 0xA0); /* ICW1: select 8259A-2 init */
309 outb_p(IRQ8_VECTOR, 0xA1); /* ICW2: 8259A-2 IR0-7 mapped to 0x38-0x3f */
310 outb_p(0x02, 0xA1); /* 8259A-2 is a slave on master's IR2 */
311 outb_p(0x01, 0xA1); /* (slave's support for AEOI in flat mode
312 is to be investigated) */
313
314 if (auto_eoi)
315 /*
316 * in AEOI mode we just have to mask the interrupt
317 * when acking.
318 */
319 i8259A_chip.mask_ack = disable_8259A_irq;
320 else
321 i8259A_chip.mask_ack = mask_and_ack_8259A;
322
323 udelay(100); /* wait for 8259A to initialize */
324
325 outb(cached_21, 0x21); /* restore master IRQ mask */
326 outb(cached_A1, 0xA1); /* restore slave IRQ mask */
327
328 spin_unlock_irqrestore(&i8259A_lock, flags);
329}
330
331static char irq_trigger[2];
332/**
333 * ELCR registers (0x4d0, 0x4d1) control edge/level of IRQ
334 */
335static void restore_ELCR(char *trigger)
336{
337 outb(trigger[0], 0x4d0);
338 outb(trigger[1], 0x4d1);
339}
340
341static void save_ELCR(char *trigger)
342{
343 /* IRQ 0,1,2,8,13 are marked as reserved */
344 trigger[0] = inb(0x4d0) & 0xF8;
345 trigger[1] = inb(0x4d1) & 0xDE;
346}
347
348static int i8259A_resume(struct sys_device *dev)
349{
350 init_8259A(i8259A_auto_eoi);
351 restore_ELCR(irq_trigger);
352 return 0;
353}
354
355static int i8259A_suspend(struct sys_device *dev, pm_message_t state)
356{
357 save_ELCR(irq_trigger);
358 return 0;
359}
360
361static int i8259A_shutdown(struct sys_device *dev)
362{
363 /* Put the i8259A into a quiescent state that
364 * the kernel initialization code can get it
365 * out of.
366 */
367 outb(0xff, 0x21); /* mask all of 8259A-1 */
368 outb(0xff, 0xA1); /* mask all of 8259A-1 */
369 return 0;
370}
371
372static struct sysdev_class i8259_sysdev_class = {
373 set_kset_name("i8259"),
374 .suspend = i8259A_suspend,
375 .resume = i8259A_resume,
376 .shutdown = i8259A_shutdown,
377};
378
379static struct sys_device device_i8259A = {
380 .id = 0,
381 .cls = &i8259_sysdev_class,
382};
383
384static int __init i8259A_init_sysfs(void)
385{
386 int error = sysdev_class_register(&i8259_sysdev_class);
387 if (!error)
388 error = sysdev_register(&device_i8259A);
389 return error;
390}
391
392device_initcall(i8259A_init_sysfs);
393
394/*
395 * IRQ2 is cascade interrupt to second interrupt controller
396 */
397
398static struct irqaction irq2 = { no_action, 0, CPU_MASK_NONE, "cascade", NULL, NULL};
399DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
400 [0 ... IRQ0_VECTOR - 1] = -1,
401 [IRQ0_VECTOR] = 0,
402 [IRQ1_VECTOR] = 1,
403 [IRQ2_VECTOR] = 2,
404 [IRQ3_VECTOR] = 3,
405 [IRQ4_VECTOR] = 4,
406 [IRQ5_VECTOR] = 5,
407 [IRQ6_VECTOR] = 6,
408 [IRQ7_VECTOR] = 7,
409 [IRQ8_VECTOR] = 8,
410 [IRQ9_VECTOR] = 9,
411 [IRQ10_VECTOR] = 10,
412 [IRQ11_VECTOR] = 11,
413 [IRQ12_VECTOR] = 12,
414 [IRQ13_VECTOR] = 13,
415 [IRQ14_VECTOR] = 14,
416 [IRQ15_VECTOR] = 15,
417 [IRQ15_VECTOR + 1 ... NR_VECTORS - 1] = -1
418};
419
420void __init init_ISA_irqs (void)
421{
422 int i;
423
424 init_bsp_APIC();
425 init_8259A(0);
426
427 for (i = 0; i < NR_IRQS; i++) {
428 irq_desc[i].status = IRQ_DISABLED;
429 irq_desc[i].action = NULL;
430 irq_desc[i].depth = 1;
431
432 if (i < 16) {
433 /*
434 * 16 old-style INTA-cycle interrupts:
435 */
436 set_irq_chip_and_handler_name(i, &i8259A_chip,
437 handle_level_irq, "XT");
438 } else {
439 /*
440 * 'high' PCI IRQs filled in on demand
441 */
442 irq_desc[i].chip = &no_irq_chip;
443 }
444 }
445}
446
447static void setup_timer_hardware(void)
448{
449 outb_p(0x34,0x43); /* binary, mode 2, LSB/MSB, ch 0 */
450 udelay(10);
451 outb_p(LATCH & 0xff , 0x40); /* LSB */
452 udelay(10);
453 outb(LATCH >> 8 , 0x40); /* MSB */
454}
455
456static int timer_resume(struct sys_device *dev)
457{
458 setup_timer_hardware();
459 return 0;
460}
461
462void i8254_timer_resume(void)
463{
464 setup_timer_hardware();
465}
466
467static struct sysdev_class timer_sysclass = {
468 set_kset_name("timer_pit"),
469 .resume = timer_resume,
470};
471
472static struct sys_device device_timer = {
473 .id = 0,
474 .cls = &timer_sysclass,
475};
476
477static int __init init_timer_sysfs(void)
478{
479 int error = sysdev_class_register(&timer_sysclass);
480 if (!error)
481 error = sysdev_register(&device_timer);
482 return error;
483}
484
485device_initcall(init_timer_sysfs);
486
487void __init init_IRQ(void)
488{
489 int i;
490
491 init_ISA_irqs();
492 /*
493 * Cover the whole vector space, no vector can escape
494 * us. (some of these will be overridden and become
495 * 'special' SMP interrupts)
496 */
497 for (i = 0; i < (NR_VECTORS - FIRST_EXTERNAL_VECTOR); i++) {
498 int vector = FIRST_EXTERNAL_VECTOR + i;
499 if (vector != IA32_SYSCALL_VECTOR)
500 set_intr_gate(vector, interrupt[i]);
501 }
502
503#ifdef CONFIG_SMP
504 /*
505 * The reschedule interrupt is a CPU-to-CPU reschedule-helper
506 * IPI, driven by wakeup.
507 */
508 set_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
509
510 /* IPIs for invalidation */
511 set_intr_gate(INVALIDATE_TLB_VECTOR_START+0, invalidate_interrupt0);
512 set_intr_gate(INVALIDATE_TLB_VECTOR_START+1, invalidate_interrupt1);
513 set_intr_gate(INVALIDATE_TLB_VECTOR_START+2, invalidate_interrupt2);
514 set_intr_gate(INVALIDATE_TLB_VECTOR_START+3, invalidate_interrupt3);
515 set_intr_gate(INVALIDATE_TLB_VECTOR_START+4, invalidate_interrupt4);
516 set_intr_gate(INVALIDATE_TLB_VECTOR_START+5, invalidate_interrupt5);
517 set_intr_gate(INVALIDATE_TLB_VECTOR_START+6, invalidate_interrupt6);
518 set_intr_gate(INVALIDATE_TLB_VECTOR_START+7, invalidate_interrupt7);
519
520 /* IPI for generic function call */
521 set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
522
523 /* Low priority IPI to cleanup after moving an irq */
524 set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
525#endif
526 set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
527 set_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
528
529 /* self generated IPI for local APIC timer */
530 set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
531
532 /* IPI vectors for APIC spurious and error interrupts */
533 set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
534 set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
535
536 /*
537 * Set the clock to HZ Hz, we already have a valid
538 * vector now:
539 */
540 setup_timer_hardware();
541
542 if (!acpi_ioapic)
543 setup_irq(2, &irq2);
544}