[PATCH] ARM SMP: TLB implementations only affect local CPU
[linux-2.6] / arch / i386 / kernel / io_apic.c
1 /*
2  *      Intel IO-APIC support for multi-Pentium hosts.
3  *
4  *      Copyright (C) 1997, 1998, 1999, 2000 Ingo Molnar, Hajnalka Szabo
5  *
6  *      Many thanks to Stig Venaas for trying out countless experimental
7  *      patches and reporting/debugging problems patiently!
8  *
9  *      (c) 1999, Multiple IO-APIC support, developed by
10  *      Ken-ichi Yaku <yaku@css1.kbnes.nec.co.jp> and
11  *      Hidemi Kishimoto <kisimoto@css1.kbnes.nec.co.jp>,
12  *      further tested and cleaned up by Zach Brown <zab@redhat.com>
13  *      and Ingo Molnar <mingo@redhat.com>
14  *
15  *      Fixes
16  *      Maciej W. Rozycki       :       Bits for genuine 82489DX APICs;
17  *                                      thanks to Eric Gilmore
18  *                                      and Rolf G. Tews
19  *                                      for testing these extensively
20  *      Paul Diefenbaugh        :       Added full ACPI support
21  */
22
23 #include <linux/mm.h>
24 #include <linux/irq.h>
25 #include <linux/interrupt.h>
26 #include <linux/init.h>
27 #include <linux/delay.h>
28 #include <linux/sched.h>
29 #include <linux/config.h>
30 #include <linux/smp_lock.h>
31 #include <linux/mc146818rtc.h>
32 #include <linux/compiler.h>
33 #include <linux/acpi.h>
34 #include <linux/module.h>
35 #include <linux/sysdev.h>
36 #include <asm/io.h>
37 #include <asm/smp.h>
38 #include <asm/desc.h>
39 #include <asm/timer.h>
40
41 #include <mach_apic.h>
42
43 #include "io_ports.h"
44
45 int (*ioapic_renumber_irq)(int ioapic, int irq);
46 atomic_t irq_mis_count;
47
48 static DEFINE_SPINLOCK(ioapic_lock);
49
50 /*
51  *      Is the SiS APIC rmw bug present ?
52  *      -1 = don't know, 0 = no, 1 = yes
53  */
54 int sis_apic_bug = -1;
55
56 /*
57  * # of IRQ routing registers
58  */
59 int nr_ioapic_registers[MAX_IO_APICS];
60
61 /*
62  * Rough estimation of how many shared IRQs there are, can
63  * be changed anytime.
64  */
65 #define MAX_PLUS_SHARED_IRQS NR_IRQS
66 #define PIN_MAP_SIZE (MAX_PLUS_SHARED_IRQS + NR_IRQS)
67
68 /*
69  * This is performance-critical, we want to do it O(1)
70  *
71  * the indexing order of this array favors 1:1 mappings
72  * between pins and IRQs.
73  */
74
75 static struct irq_pin_list {
76         int apic, pin, next;
77 } irq_2_pin[PIN_MAP_SIZE];
78
79 int vector_irq[NR_VECTORS] = { [0 ... NR_VECTORS - 1] = -1};
80 #ifdef CONFIG_PCI_MSI
81 #define vector_to_irq(vector)   \
82         (platform_legacy_irq(vector) ? vector : vector_irq[vector])
83 #else
84 #define vector_to_irq(vector)   (vector)
85 #endif
86
87 /*
88  * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
89  * shared ISA-space IRQs, so we have to support them. We are super
90  * fast in the common case, and fast for shared ISA-space IRQs.
91  */
92 static void add_pin_to_irq(unsigned int irq, int apic, int pin)
93 {
94         static int first_free_entry = NR_IRQS;
95         struct irq_pin_list *entry = irq_2_pin + irq;
96
97         while (entry->next)
98                 entry = irq_2_pin + entry->next;
99
100         if (entry->pin != -1) {
101                 entry->next = first_free_entry;
102                 entry = irq_2_pin + entry->next;
103                 if (++first_free_entry >= PIN_MAP_SIZE)
104                         panic("io_apic.c: whoops");
105         }
106         entry->apic = apic;
107         entry->pin = pin;
108 }
109
110 /*
111  * Reroute an IRQ to a different pin.
112  */
113 static void __init replace_pin_at_irq(unsigned int irq,
114                                       int oldapic, int oldpin,
115                                       int newapic, int newpin)
116 {
117         struct irq_pin_list *entry = irq_2_pin + irq;
118
119         while (1) {
120                 if (entry->apic == oldapic && entry->pin == oldpin) {
121                         entry->apic = newapic;
122                         entry->pin = newpin;
123                 }
124                 if (!entry->next)
125                         break;
126                 entry = irq_2_pin + entry->next;
127         }
128 }
129
130 static void __modify_IO_APIC_irq (unsigned int irq, unsigned long enable, unsigned long disable)
131 {
132         struct irq_pin_list *entry = irq_2_pin + irq;
133         unsigned int pin, reg;
134
135         for (;;) {
136                 pin = entry->pin;
137                 if (pin == -1)
138                         break;
139                 reg = io_apic_read(entry->apic, 0x10 + pin*2);
140                 reg &= ~disable;
141                 reg |= enable;
142                 io_apic_modify(entry->apic, 0x10 + pin*2, reg);
143                 if (!entry->next)
144                         break;
145                 entry = irq_2_pin + entry->next;
146         }
147 }
148
149 /* mask = 1 */
150 static void __mask_IO_APIC_irq (unsigned int irq)
151 {
152         __modify_IO_APIC_irq(irq, 0x00010000, 0);
153 }
154
155 /* mask = 0 */
156 static void __unmask_IO_APIC_irq (unsigned int irq)
157 {
158         __modify_IO_APIC_irq(irq, 0, 0x00010000);
159 }
160
161 /* mask = 1, trigger = 0 */
162 static void __mask_and_edge_IO_APIC_irq (unsigned int irq)
163 {
164         __modify_IO_APIC_irq(irq, 0x00010000, 0x00008000);
165 }
166
167 /* mask = 0, trigger = 1 */
168 static void __unmask_and_level_IO_APIC_irq (unsigned int irq)
169 {
170         __modify_IO_APIC_irq(irq, 0x00008000, 0x00010000);
171 }
172
173 static void mask_IO_APIC_irq (unsigned int irq)
174 {
175         unsigned long flags;
176
177         spin_lock_irqsave(&ioapic_lock, flags);
178         __mask_IO_APIC_irq(irq);
179         spin_unlock_irqrestore(&ioapic_lock, flags);
180 }
181
182 static void unmask_IO_APIC_irq (unsigned int irq)
183 {
184         unsigned long flags;
185
186         spin_lock_irqsave(&ioapic_lock, flags);
187         __unmask_IO_APIC_irq(irq);
188         spin_unlock_irqrestore(&ioapic_lock, flags);
189 }
190
191 static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
192 {
193         struct IO_APIC_route_entry entry;
194         unsigned long flags;
195         
196         /* Check delivery_mode to be sure we're not clearing an SMI pin */
197         spin_lock_irqsave(&ioapic_lock, flags);
198         *(((int*)&entry) + 0) = io_apic_read(apic, 0x10 + 2 * pin);
199         *(((int*)&entry) + 1) = io_apic_read(apic, 0x11 + 2 * pin);
200         spin_unlock_irqrestore(&ioapic_lock, flags);
201         if (entry.delivery_mode == dest_SMI)
202                 return;
203
204         /*
205          * Disable it in the IO-APIC irq-routing table:
206          */
207         memset(&entry, 0, sizeof(entry));
208         entry.mask = 1;
209         spin_lock_irqsave(&ioapic_lock, flags);
210         io_apic_write(apic, 0x10 + 2 * pin, *(((int *)&entry) + 0));
211         io_apic_write(apic, 0x11 + 2 * pin, *(((int *)&entry) + 1));
212         spin_unlock_irqrestore(&ioapic_lock, flags);
213 }
214
215 static void clear_IO_APIC (void)
216 {
217         int apic, pin;
218
219         for (apic = 0; apic < nr_ioapics; apic++)
220                 for (pin = 0; pin < nr_ioapic_registers[apic]; pin++)
221                         clear_IO_APIC_pin(apic, pin);
222 }
223
224 static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t cpumask)
225 {
226         unsigned long flags;
227         int pin;
228         struct irq_pin_list *entry = irq_2_pin + irq;
229         unsigned int apicid_value;
230         
231         apicid_value = cpu_mask_to_apicid(cpumask);
232         /* Prepare to do the io_apic_write */
233         apicid_value = apicid_value << 24;
234         spin_lock_irqsave(&ioapic_lock, flags);
235         for (;;) {
236                 pin = entry->pin;
237                 if (pin == -1)
238                         break;
239                 io_apic_write(entry->apic, 0x10 + 1 + pin*2, apicid_value);
240                 if (!entry->next)
241                         break;
242                 entry = irq_2_pin + entry->next;
243         }
244         spin_unlock_irqrestore(&ioapic_lock, flags);
245 }
246
247 #if defined(CONFIG_IRQBALANCE)
248 # include <asm/processor.h>     /* kernel_thread() */
249 # include <linux/kernel_stat.h> /* kstat */
250 # include <linux/slab.h>                /* kmalloc() */
251 # include <linux/timer.h>       /* time_after() */
252  
253 # ifdef CONFIG_BALANCED_IRQ_DEBUG
254 #  define TDprintk(x...) do { printk("<%ld:%s:%d>: ", jiffies, __FILE__, __LINE__); printk(x); } while (0)
255 #  define Dprintk(x...) do { TDprintk(x); } while (0)
256 # else
257 #  define TDprintk(x...) 
258 #  define Dprintk(x...) 
259 # endif
260
261 cpumask_t __cacheline_aligned pending_irq_balance_cpumask[NR_IRQS];
262
263 #define IRQBALANCE_CHECK_ARCH -999
264 static int irqbalance_disabled = IRQBALANCE_CHECK_ARCH;
265 static int physical_balance = 0;
266
267 static struct irq_cpu_info {
268         unsigned long * last_irq;
269         unsigned long * irq_delta;
270         unsigned long irq;
271 } irq_cpu_data[NR_CPUS];
272
273 #define CPU_IRQ(cpu)            (irq_cpu_data[cpu].irq)
274 #define LAST_CPU_IRQ(cpu,irq)   (irq_cpu_data[cpu].last_irq[irq])
275 #define IRQ_DELTA(cpu,irq)      (irq_cpu_data[cpu].irq_delta[irq])
276
277 #define IDLE_ENOUGH(cpu,now) \
278         (idle_cpu(cpu) && ((now) - per_cpu(irq_stat, (cpu)).idle_timestamp > 1))
279
280 #define IRQ_ALLOWED(cpu, allowed_mask)  cpu_isset(cpu, allowed_mask)
281
282 #define CPU_TO_PACKAGEINDEX(i) (first_cpu(cpu_sibling_map[i]))
283
284 #define MAX_BALANCED_IRQ_INTERVAL       (5*HZ)
285 #define MIN_BALANCED_IRQ_INTERVAL       (HZ/2)
286 #define BALANCED_IRQ_MORE_DELTA         (HZ/10)
287 #define BALANCED_IRQ_LESS_DELTA         (HZ)
288
289 static long balanced_irq_interval = MAX_BALANCED_IRQ_INTERVAL;
290
291 static unsigned long move(int curr_cpu, cpumask_t allowed_mask,
292                         unsigned long now, int direction)
293 {
294         int search_idle = 1;
295         int cpu = curr_cpu;
296
297         goto inside;
298
299         do {
300                 if (unlikely(cpu == curr_cpu))
301                         search_idle = 0;
302 inside:
303                 if (direction == 1) {
304                         cpu++;
305                         if (cpu >= NR_CPUS)
306                                 cpu = 0;
307                 } else {
308                         cpu--;
309                         if (cpu == -1)
310                                 cpu = NR_CPUS-1;
311                 }
312         } while (!cpu_online(cpu) || !IRQ_ALLOWED(cpu,allowed_mask) ||
313                         (search_idle && !IDLE_ENOUGH(cpu,now)));
314
315         return cpu;
316 }
317
318 static inline void balance_irq(int cpu, int irq)
319 {
320         unsigned long now = jiffies;
321         cpumask_t allowed_mask;
322         unsigned int new_cpu;
323                 
324         if (irqbalance_disabled)
325                 return; 
326
327         cpus_and(allowed_mask, cpu_online_map, irq_affinity[irq]);
328         new_cpu = move(cpu, allowed_mask, now, 1);
329         if (cpu != new_cpu) {
330                 irq_desc_t *desc = irq_desc + irq;
331                 unsigned long flags;
332
333                 spin_lock_irqsave(&desc->lock, flags);
334                 pending_irq_balance_cpumask[irq] = cpumask_of_cpu(new_cpu);
335                 spin_unlock_irqrestore(&desc->lock, flags);
336         }
337 }
338
339 static inline void rotate_irqs_among_cpus(unsigned long useful_load_threshold)
340 {
341         int i, j;
342         Dprintk("Rotating IRQs among CPUs.\n");
343         for (i = 0; i < NR_CPUS; i++) {
344                 for (j = 0; cpu_online(i) && (j < NR_IRQS); j++) {
345                         if (!irq_desc[j].action)
346                                 continue;
347                         /* Is it a significant load ?  */
348                         if (IRQ_DELTA(CPU_TO_PACKAGEINDEX(i),j) <
349                                                 useful_load_threshold)
350                                 continue;
351                         balance_irq(i, j);
352                 }
353         }
354         balanced_irq_interval = max((long)MIN_BALANCED_IRQ_INTERVAL,
355                 balanced_irq_interval - BALANCED_IRQ_LESS_DELTA);       
356         return;
357 }
358
359 static void do_irq_balance(void)
360 {
361         int i, j;
362         unsigned long max_cpu_irq = 0, min_cpu_irq = (~0);
363         unsigned long move_this_load = 0;
364         int max_loaded = 0, min_loaded = 0;
365         int load;
366         unsigned long useful_load_threshold = balanced_irq_interval + 10;
367         int selected_irq;
368         int tmp_loaded, first_attempt = 1;
369         unsigned long tmp_cpu_irq;
370         unsigned long imbalance = 0;
371         cpumask_t allowed_mask, target_cpu_mask, tmp;
372
373         for (i = 0; i < NR_CPUS; i++) {
374                 int package_index;
375                 CPU_IRQ(i) = 0;
376                 if (!cpu_online(i))
377                         continue;
378                 package_index = CPU_TO_PACKAGEINDEX(i);
379                 for (j = 0; j < NR_IRQS; j++) {
380                         unsigned long value_now, delta;
381                         /* Is this an active IRQ? */
382                         if (!irq_desc[j].action)
383                                 continue;
384                         if ( package_index == i )
385                                 IRQ_DELTA(package_index,j) = 0;
386                         /* Determine the total count per processor per IRQ */
387                         value_now = (unsigned long) kstat_cpu(i).irqs[j];
388
389                         /* Determine the activity per processor per IRQ */
390                         delta = value_now - LAST_CPU_IRQ(i,j);
391
392                         /* Update last_cpu_irq[][] for the next time */
393                         LAST_CPU_IRQ(i,j) = value_now;
394
395                         /* Ignore IRQs whose rate is less than the clock */
396                         if (delta < useful_load_threshold)
397                                 continue;
398                         /* update the load for the processor or package total */
399                         IRQ_DELTA(package_index,j) += delta;
400
401                         /* Keep track of the higher numbered sibling as well */
402                         if (i != package_index)
403                                 CPU_IRQ(i) += delta;
404                         /*
405                          * We have sibling A and sibling B in the package
406                          *
407                          * cpu_irq[A] = load for cpu A + load for cpu B
408                          * cpu_irq[B] = load for cpu B
409                          */
410                         CPU_IRQ(package_index) += delta;
411                 }
412         }
413         /* Find the least loaded processor package */
414         for (i = 0; i < NR_CPUS; i++) {
415                 if (!cpu_online(i))
416                         continue;
417                 if (i != CPU_TO_PACKAGEINDEX(i))
418                         continue;
419                 if (min_cpu_irq > CPU_IRQ(i)) {
420                         min_cpu_irq = CPU_IRQ(i);
421                         min_loaded = i;
422                 }
423         }
424         max_cpu_irq = ULONG_MAX;
425
426 tryanothercpu:
427         /* Look for heaviest loaded processor.
428          * We may come back to get the next heaviest loaded processor.
429          * Skip processors with trivial loads.
430          */
431         tmp_cpu_irq = 0;
432         tmp_loaded = -1;
433         for (i = 0; i < NR_CPUS; i++) {
434                 if (!cpu_online(i))
435                         continue;
436                 if (i != CPU_TO_PACKAGEINDEX(i))
437                         continue;
438                 if (max_cpu_irq <= CPU_IRQ(i)) 
439                         continue;
440                 if (tmp_cpu_irq < CPU_IRQ(i)) {
441                         tmp_cpu_irq = CPU_IRQ(i);
442                         tmp_loaded = i;
443                 }
444         }
445
446         if (tmp_loaded == -1) {
447          /* In the case of small number of heavy interrupt sources, 
448           * loading some of the cpus too much. We use Ingo's original 
449           * approach to rotate them around.
450           */
451                 if (!first_attempt && imbalance >= useful_load_threshold) {
452                         rotate_irqs_among_cpus(useful_load_threshold);
453                         return;
454                 }
455                 goto not_worth_the_effort;
456         }
457         
458         first_attempt = 0;              /* heaviest search */
459         max_cpu_irq = tmp_cpu_irq;      /* load */
460         max_loaded = tmp_loaded;        /* processor */
461         imbalance = (max_cpu_irq - min_cpu_irq) / 2;
462         
463         Dprintk("max_loaded cpu = %d\n", max_loaded);
464         Dprintk("min_loaded cpu = %d\n", min_loaded);
465         Dprintk("max_cpu_irq load = %ld\n", max_cpu_irq);
466         Dprintk("min_cpu_irq load = %ld\n", min_cpu_irq);
467         Dprintk("load imbalance = %lu\n", imbalance);
468
469         /* if imbalance is less than approx 10% of max load, then
470          * observe diminishing returns action. - quit
471          */
472         if (imbalance < (max_cpu_irq >> 3)) {
473                 Dprintk("Imbalance too trivial\n");
474                 goto not_worth_the_effort;
475         }
476
477 tryanotherirq:
478         /* if we select an IRQ to move that can't go where we want, then
479          * see if there is another one to try.
480          */
481         move_this_load = 0;
482         selected_irq = -1;
483         for (j = 0; j < NR_IRQS; j++) {
484                 /* Is this an active IRQ? */
485                 if (!irq_desc[j].action)
486                         continue;
487                 if (imbalance <= IRQ_DELTA(max_loaded,j))
488                         continue;
489                 /* Try to find the IRQ that is closest to the imbalance
490                  * without going over.
491                  */
492                 if (move_this_load < IRQ_DELTA(max_loaded,j)) {
493                         move_this_load = IRQ_DELTA(max_loaded,j);
494                         selected_irq = j;
495                 }
496         }
497         if (selected_irq == -1) {
498                 goto tryanothercpu;
499         }
500
501         imbalance = move_this_load;
502         
503         /* For physical_balance case, we accumlated both load
504          * values in the one of the siblings cpu_irq[],
505          * to use the same code for physical and logical processors
506          * as much as possible. 
507          *
508          * NOTE: the cpu_irq[] array holds the sum of the load for
509          * sibling A and sibling B in the slot for the lowest numbered
510          * sibling (A), _AND_ the load for sibling B in the slot for
511          * the higher numbered sibling.
512          *
513          * We seek the least loaded sibling by making the comparison
514          * (A+B)/2 vs B
515          */
516         load = CPU_IRQ(min_loaded) >> 1;
517         for_each_cpu_mask(j, cpu_sibling_map[min_loaded]) {
518                 if (load > CPU_IRQ(j)) {
519                         /* This won't change cpu_sibling_map[min_loaded] */
520                         load = CPU_IRQ(j);
521                         min_loaded = j;
522                 }
523         }
524
525         cpus_and(allowed_mask, cpu_online_map, irq_affinity[selected_irq]);
526         target_cpu_mask = cpumask_of_cpu(min_loaded);
527         cpus_and(tmp, target_cpu_mask, allowed_mask);
528
529         if (!cpus_empty(tmp)) {
530                 irq_desc_t *desc = irq_desc + selected_irq;
531                 unsigned long flags;
532
533                 Dprintk("irq = %d moved to cpu = %d\n",
534                                 selected_irq, min_loaded);
535                 /* mark for change destination */
536                 spin_lock_irqsave(&desc->lock, flags);
537                 pending_irq_balance_cpumask[selected_irq] =
538                                         cpumask_of_cpu(min_loaded);
539                 spin_unlock_irqrestore(&desc->lock, flags);
540                 /* Since we made a change, come back sooner to 
541                  * check for more variation.
542                  */
543                 balanced_irq_interval = max((long)MIN_BALANCED_IRQ_INTERVAL,
544                         balanced_irq_interval - BALANCED_IRQ_LESS_DELTA);       
545                 return;
546         }
547         goto tryanotherirq;
548
549 not_worth_the_effort:
550         /*
551          * if we did not find an IRQ to move, then adjust the time interval
552          * upward
553          */
554         balanced_irq_interval = min((long)MAX_BALANCED_IRQ_INTERVAL,
555                 balanced_irq_interval + BALANCED_IRQ_MORE_DELTA);       
556         Dprintk("IRQ worth rotating not found\n");
557         return;
558 }
559
560 static int balanced_irq(void *unused)
561 {
562         int i;
563         unsigned long prev_balance_time = jiffies;
564         long time_remaining = balanced_irq_interval;
565
566         daemonize("kirqd");
567         
568         /* push everything to CPU 0 to give us a starting point.  */
569         for (i = 0 ; i < NR_IRQS ; i++) {
570                 pending_irq_balance_cpumask[i] = cpumask_of_cpu(0);
571         }
572
573         for ( ; ; ) {
574                 set_current_state(TASK_INTERRUPTIBLE);
575                 time_remaining = schedule_timeout(time_remaining);
576                 try_to_freeze();
577                 if (time_after(jiffies,
578                                 prev_balance_time+balanced_irq_interval)) {
579                         preempt_disable();
580                         do_irq_balance();
581                         prev_balance_time = jiffies;
582                         time_remaining = balanced_irq_interval;
583                         preempt_enable();
584                 }
585         }
586         return 0;
587 }
588
589 static int __init balanced_irq_init(void)
590 {
591         int i;
592         struct cpuinfo_x86 *c;
593         cpumask_t tmp;
594
595         cpus_shift_right(tmp, cpu_online_map, 2);
596         c = &boot_cpu_data;
597         /* When not overwritten by the command line ask subarchitecture. */
598         if (irqbalance_disabled == IRQBALANCE_CHECK_ARCH)
599                 irqbalance_disabled = NO_BALANCE_IRQ;
600         if (irqbalance_disabled)
601                 return 0;
602         
603          /* disable irqbalance completely if there is only one processor online */
604         if (num_online_cpus() < 2) {
605                 irqbalance_disabled = 1;
606                 return 0;
607         }
608         /*
609          * Enable physical balance only if more than 1 physical processor
610          * is present
611          */
612         if (smp_num_siblings > 1 && !cpus_empty(tmp))
613                 physical_balance = 1;
614
615         for (i = 0; i < NR_CPUS; i++) {
616                 if (!cpu_online(i))
617                         continue;
618                 irq_cpu_data[i].irq_delta = kmalloc(sizeof(unsigned long) * NR_IRQS, GFP_KERNEL);
619                 irq_cpu_data[i].last_irq = kmalloc(sizeof(unsigned long) * NR_IRQS, GFP_KERNEL);
620                 if (irq_cpu_data[i].irq_delta == NULL || irq_cpu_data[i].last_irq == NULL) {
621                         printk(KERN_ERR "balanced_irq_init: out of memory");
622                         goto failed;
623                 }
624                 memset(irq_cpu_data[i].irq_delta,0,sizeof(unsigned long) * NR_IRQS);
625                 memset(irq_cpu_data[i].last_irq,0,sizeof(unsigned long) * NR_IRQS);
626         }
627         
628         printk(KERN_INFO "Starting balanced_irq\n");
629         if (kernel_thread(balanced_irq, NULL, CLONE_KERNEL) >= 0) 
630                 return 0;
631         else 
632                 printk(KERN_ERR "balanced_irq_init: failed to spawn balanced_irq");
633 failed:
634         for (i = 0; i < NR_CPUS; i++) {
635                 kfree(irq_cpu_data[i].irq_delta);
636                 kfree(irq_cpu_data[i].last_irq);
637         }
638         return 0;
639 }
640
641 int __init irqbalance_disable(char *str)
642 {
643         irqbalance_disabled = 1;
644         return 0;
645 }
646
647 __setup("noirqbalance", irqbalance_disable);
648
649 static inline void move_irq(int irq)
650 {
651         /* note - we hold the desc->lock */
652         if (unlikely(!cpus_empty(pending_irq_balance_cpumask[irq]))) {
653                 set_ioapic_affinity_irq(irq, pending_irq_balance_cpumask[irq]);
654                 cpus_clear(pending_irq_balance_cpumask[irq]);
655         }
656 }
657
658 late_initcall(balanced_irq_init);
659
660 #else /* !CONFIG_IRQBALANCE */
661 static inline void move_irq(int irq) { }
662 #endif /* CONFIG_IRQBALANCE */
663
664 #ifndef CONFIG_SMP
665 void fastcall send_IPI_self(int vector)
666 {
667         unsigned int cfg;
668
669         /*
670          * Wait for idle.
671          */
672         apic_wait_icr_idle();
673         cfg = APIC_DM_FIXED | APIC_DEST_SELF | vector | APIC_DEST_LOGICAL;
674         /*
675          * Send the IPI. The write to APIC_ICR fires this off.
676          */
677         apic_write_around(APIC_ICR, cfg);
678 }
679 #endif /* !CONFIG_SMP */
680
681
682 /*
683  * support for broken MP BIOSs, enables hand-redirection of PIRQ0-7 to
684  * specific CPU-side IRQs.
685  */
686
687 #define MAX_PIRQS 8
688 static int pirq_entries [MAX_PIRQS];
689 static int pirqs_enabled;
690 int skip_ioapic_setup;
691
692 static int __init ioapic_setup(char *str)
693 {
694         skip_ioapic_setup = 1;
695         return 1;
696 }
697
698 __setup("noapic", ioapic_setup);
699
700 static int __init ioapic_pirq_setup(char *str)
701 {
702         int i, max;
703         int ints[MAX_PIRQS+1];
704
705         get_options(str, ARRAY_SIZE(ints), ints);
706
707         for (i = 0; i < MAX_PIRQS; i++)
708                 pirq_entries[i] = -1;
709
710         pirqs_enabled = 1;
711         apic_printk(APIC_VERBOSE, KERN_INFO
712                         "PIRQ redirection, working around broken MP-BIOS.\n");
713         max = MAX_PIRQS;
714         if (ints[0] < MAX_PIRQS)
715                 max = ints[0];
716
717         for (i = 0; i < max; i++) {
718                 apic_printk(APIC_VERBOSE, KERN_DEBUG
719                                 "... PIRQ%d -> IRQ %d\n", i, ints[i+1]);
720                 /*
721                  * PIRQs are mapped upside down, usually.
722                  */
723                 pirq_entries[MAX_PIRQS-i-1] = ints[i+1];
724         }
725         return 1;
726 }
727
728 __setup("pirq=", ioapic_pirq_setup);
729
730 /*
731  * Find the IRQ entry number of a certain pin.
732  */
733 static int find_irq_entry(int apic, int pin, int type)
734 {
735         int i;
736
737         for (i = 0; i < mp_irq_entries; i++)
738                 if (mp_irqs[i].mpc_irqtype == type &&
739                     (mp_irqs[i].mpc_dstapic == mp_ioapics[apic].mpc_apicid ||
740                      mp_irqs[i].mpc_dstapic == MP_APIC_ALL) &&
741                     mp_irqs[i].mpc_dstirq == pin)
742                         return i;
743
744         return -1;
745 }
746
747 /*
748  * Find the pin to which IRQ[irq] (ISA) is connected
749  */
750 static int find_isa_irq_pin(int irq, int type)
751 {
752         int i;
753
754         for (i = 0; i < mp_irq_entries; i++) {
755                 int lbus = mp_irqs[i].mpc_srcbus;
756
757                 if ((mp_bus_id_to_type[lbus] == MP_BUS_ISA ||
758                      mp_bus_id_to_type[lbus] == MP_BUS_EISA ||
759                      mp_bus_id_to_type[lbus] == MP_BUS_MCA ||
760                      mp_bus_id_to_type[lbus] == MP_BUS_NEC98
761                     ) &&
762                     (mp_irqs[i].mpc_irqtype == type) &&
763                     (mp_irqs[i].mpc_srcbusirq == irq))
764
765                         return mp_irqs[i].mpc_dstirq;
766         }
767         return -1;
768 }
769
770 /*
771  * Find a specific PCI IRQ entry.
772  * Not an __init, possibly needed by modules
773  */
774 static int pin_2_irq(int idx, int apic, int pin);
775
776 int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
777 {
778         int apic, i, best_guess = -1;
779
780         apic_printk(APIC_DEBUG, "querying PCI -> IRQ mapping bus:%d, "
781                 "slot:%d, pin:%d.\n", bus, slot, pin);
782         if (mp_bus_id_to_pci_bus[bus] == -1) {
783                 printk(KERN_WARNING "PCI BIOS passed nonexistent PCI bus %d!\n", bus);
784                 return -1;
785         }
786         for (i = 0; i < mp_irq_entries; i++) {
787                 int lbus = mp_irqs[i].mpc_srcbus;
788
789                 for (apic = 0; apic < nr_ioapics; apic++)
790                         if (mp_ioapics[apic].mpc_apicid == mp_irqs[i].mpc_dstapic ||
791                             mp_irqs[i].mpc_dstapic == MP_APIC_ALL)
792                                 break;
793
794                 if ((mp_bus_id_to_type[lbus] == MP_BUS_PCI) &&
795                     !mp_irqs[i].mpc_irqtype &&
796                     (bus == lbus) &&
797                     (slot == ((mp_irqs[i].mpc_srcbusirq >> 2) & 0x1f))) {
798                         int irq = pin_2_irq(i,apic,mp_irqs[i].mpc_dstirq);
799
800                         if (!(apic || IO_APIC_IRQ(irq)))
801                                 continue;
802
803                         if (pin == (mp_irqs[i].mpc_srcbusirq & 3))
804                                 return irq;
805                         /*
806                          * Use the first all-but-pin matching entry as a
807                          * best-guess fuzzy result for broken mptables.
808                          */
809                         if (best_guess < 0)
810                                 best_guess = irq;
811                 }
812         }
813         return best_guess;
814 }
815 EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);
816
817 /*
818  * This function currently is only a helper for the i386 smp boot process where 
819  * we need to reprogram the ioredtbls to cater for the cpus which have come online
820  * so mask in all cases should simply be TARGET_CPUS
821  */
822 void __init setup_ioapic_dest(void)
823 {
824         int pin, ioapic, irq, irq_entry;
825
826         if (skip_ioapic_setup == 1)
827                 return;
828
829         for (ioapic = 0; ioapic < nr_ioapics; ioapic++) {
830                 for (pin = 0; pin < nr_ioapic_registers[ioapic]; pin++) {
831                         irq_entry = find_irq_entry(ioapic, pin, mp_INT);
832                         if (irq_entry == -1)
833                                 continue;
834                         irq = pin_2_irq(irq_entry, ioapic, pin);
835                         set_ioapic_affinity_irq(irq, TARGET_CPUS);
836                 }
837
838         }
839 }
840
841 /*
842  * EISA Edge/Level control register, ELCR
843  */
844 static int EISA_ELCR(unsigned int irq)
845 {
846         if (irq < 16) {
847                 unsigned int port = 0x4d0 + (irq >> 3);
848                 return (inb(port) >> (irq & 7)) & 1;
849         }
850         apic_printk(APIC_VERBOSE, KERN_INFO
851                         "Broken MPtable reports ISA irq %d\n", irq);
852         return 0;
853 }
854
855 /* EISA interrupts are always polarity zero and can be edge or level
856  * trigger depending on the ELCR value.  If an interrupt is listed as
857  * EISA conforming in the MP table, that means its trigger type must
858  * be read in from the ELCR */
859
860 #define default_EISA_trigger(idx)       (EISA_ELCR(mp_irqs[idx].mpc_srcbusirq))
861 #define default_EISA_polarity(idx)      (0)
862
863 /* ISA interrupts are always polarity zero edge triggered,
864  * when listed as conforming in the MP table. */
865
866 #define default_ISA_trigger(idx)        (0)
867 #define default_ISA_polarity(idx)       (0)
868
869 /* PCI interrupts are always polarity one level triggered,
870  * when listed as conforming in the MP table. */
871
872 #define default_PCI_trigger(idx)        (1)
873 #define default_PCI_polarity(idx)       (1)
874
875 /* MCA interrupts are always polarity zero level triggered,
876  * when listed as conforming in the MP table. */
877
878 #define default_MCA_trigger(idx)        (1)
879 #define default_MCA_polarity(idx)       (0)
880
881 /* NEC98 interrupts are always polarity zero edge triggered,
882  * when listed as conforming in the MP table. */
883
884 #define default_NEC98_trigger(idx)     (0)
885 #define default_NEC98_polarity(idx)    (0)
886
887 static int __init MPBIOS_polarity(int idx)
888 {
889         int bus = mp_irqs[idx].mpc_srcbus;
890         int polarity;
891
892         /*
893          * Determine IRQ line polarity (high active or low active):
894          */
895         switch (mp_irqs[idx].mpc_irqflag & 3)
896         {
897                 case 0: /* conforms, ie. bus-type dependent polarity */
898                 {
899                         switch (mp_bus_id_to_type[bus])
900                         {
901                                 case MP_BUS_ISA: /* ISA pin */
902                                 {
903                                         polarity = default_ISA_polarity(idx);
904                                         break;
905                                 }
906                                 case MP_BUS_EISA: /* EISA pin */
907                                 {
908                                         polarity = default_EISA_polarity(idx);
909                                         break;
910                                 }
911                                 case MP_BUS_PCI: /* PCI pin */
912                                 {
913                                         polarity = default_PCI_polarity(idx);
914                                         break;
915                                 }
916                                 case MP_BUS_MCA: /* MCA pin */
917                                 {
918                                         polarity = default_MCA_polarity(idx);
919                                         break;
920                                 }
921                                 case MP_BUS_NEC98: /* NEC 98 pin */
922                                 {
923                                         polarity = default_NEC98_polarity(idx);
924                                         break;
925                                 }
926                                 default:
927                                 {
928                                         printk(KERN_WARNING "broken BIOS!!\n");
929                                         polarity = 1;
930                                         break;
931                                 }
932                         }
933                         break;
934                 }
935                 case 1: /* high active */
936                 {
937                         polarity = 0;
938                         break;
939                 }
940                 case 2: /* reserved */
941                 {
942                         printk(KERN_WARNING "broken BIOS!!\n");
943                         polarity = 1;
944                         break;
945                 }
946                 case 3: /* low active */
947                 {
948                         polarity = 1;
949                         break;
950                 }
951                 default: /* invalid */
952                 {
953                         printk(KERN_WARNING "broken BIOS!!\n");
954                         polarity = 1;
955                         break;
956                 }
957         }
958         return polarity;
959 }
960
961 static int MPBIOS_trigger(int idx)
962 {
963         int bus = mp_irqs[idx].mpc_srcbus;
964         int trigger;
965
966         /*
967          * Determine IRQ trigger mode (edge or level sensitive):
968          */
969         switch ((mp_irqs[idx].mpc_irqflag>>2) & 3)
970         {
971                 case 0: /* conforms, ie. bus-type dependent */
972                 {
973                         switch (mp_bus_id_to_type[bus])
974                         {
975                                 case MP_BUS_ISA: /* ISA pin */
976                                 {
977                                         trigger = default_ISA_trigger(idx);
978                                         break;
979                                 }
980                                 case MP_BUS_EISA: /* EISA pin */
981                                 {
982                                         trigger = default_EISA_trigger(idx);
983                                         break;
984                                 }
985                                 case MP_BUS_PCI: /* PCI pin */
986                                 {
987                                         trigger = default_PCI_trigger(idx);
988                                         break;
989                                 }
990                                 case MP_BUS_MCA: /* MCA pin */
991                                 {
992                                         trigger = default_MCA_trigger(idx);
993                                         break;
994                                 }
995                                 case MP_BUS_NEC98: /* NEC 98 pin */
996                                 {
997                                         trigger = default_NEC98_trigger(idx);
998                                         break;
999                                 }
1000                                 default:
1001                                 {
1002                                         printk(KERN_WARNING "broken BIOS!!\n");
1003                                         trigger = 1;
1004                                         break;
1005                                 }
1006                         }
1007                         break;
1008                 }
1009                 case 1: /* edge */
1010                 {
1011                         trigger = 0;
1012                         break;
1013                 }
1014                 case 2: /* reserved */
1015                 {
1016                         printk(KERN_WARNING "broken BIOS!!\n");
1017                         trigger = 1;
1018                         break;
1019                 }
1020                 case 3: /* level */
1021                 {
1022                         trigger = 1;
1023                         break;
1024                 }
1025                 default: /* invalid */
1026                 {
1027                         printk(KERN_WARNING "broken BIOS!!\n");
1028                         trigger = 0;
1029                         break;
1030                 }
1031         }
1032         return trigger;
1033 }
1034
1035 static inline int irq_polarity(int idx)
1036 {
1037         return MPBIOS_polarity(idx);
1038 }
1039
1040 static inline int irq_trigger(int idx)
1041 {
1042         return MPBIOS_trigger(idx);
1043 }
1044
1045 static int pin_2_irq(int idx, int apic, int pin)
1046 {
1047         int irq, i;
1048         int bus = mp_irqs[idx].mpc_srcbus;
1049
1050         /*
1051          * Debugging check, we are in big trouble if this message pops up!
1052          */
1053         if (mp_irqs[idx].mpc_dstirq != pin)
1054                 printk(KERN_ERR "broken BIOS or MPTABLE parser, ayiee!!\n");
1055
1056         switch (mp_bus_id_to_type[bus])
1057         {
1058                 case MP_BUS_ISA: /* ISA pin */
1059                 case MP_BUS_EISA:
1060                 case MP_BUS_MCA:
1061                 case MP_BUS_NEC98:
1062                 {
1063                         irq = mp_irqs[idx].mpc_srcbusirq;
1064                         break;
1065                 }
1066                 case MP_BUS_PCI: /* PCI pin */
1067                 {
1068                         /*
1069                          * PCI IRQs are mapped in order
1070                          */
1071                         i = irq = 0;
1072                         while (i < apic)
1073                                 irq += nr_ioapic_registers[i++];
1074                         irq += pin;
1075
1076                         /*
1077                          * For MPS mode, so far only needed by ES7000 platform
1078                          */
1079                         if (ioapic_renumber_irq)
1080                                 irq = ioapic_renumber_irq(apic, irq);
1081
1082                         break;
1083                 }
1084                 default:
1085                 {
1086                         printk(KERN_ERR "unknown bus type %d.\n",bus); 
1087                         irq = 0;
1088                         break;
1089                 }
1090         }
1091
1092         /*
1093          * PCI IRQ command line redirection. Yes, limits are hardcoded.
1094          */
1095         if ((pin >= 16) && (pin <= 23)) {
1096                 if (pirq_entries[pin-16] != -1) {
1097                         if (!pirq_entries[pin-16]) {
1098                                 apic_printk(APIC_VERBOSE, KERN_DEBUG
1099                                                 "disabling PIRQ%d\n", pin-16);
1100                         } else {
1101                                 irq = pirq_entries[pin-16];
1102                                 apic_printk(APIC_VERBOSE, KERN_DEBUG
1103                                                 "using PIRQ%d -> IRQ %d\n",
1104                                                 pin-16, irq);
1105                         }
1106                 }
1107         }
1108         return irq;
1109 }
1110
1111 static inline int IO_APIC_irq_trigger(int irq)
1112 {
1113         int apic, idx, pin;
1114
1115         for (apic = 0; apic < nr_ioapics; apic++) {
1116                 for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
1117                         idx = find_irq_entry(apic,pin,mp_INT);
1118                         if ((idx != -1) && (irq == pin_2_irq(idx,apic,pin)))
1119                                 return irq_trigger(idx);
1120                 }
1121         }
1122         /*
1123          * nonexistent IRQs are edge default
1124          */
1125         return 0;
1126 }
1127
1128 /* irq_vectors is indexed by the sum of all RTEs in all I/O APICs. */
1129 u8 irq_vector[NR_IRQ_VECTORS] = { FIRST_DEVICE_VECTOR , 0 };
1130
1131 int assign_irq_vector(int irq)
1132 {
1133         static int current_vector = FIRST_DEVICE_VECTOR, offset = 0;
1134
1135         BUG_ON(irq >= NR_IRQ_VECTORS);
1136         if (irq != AUTO_ASSIGN && IO_APIC_VECTOR(irq) > 0)
1137                 return IO_APIC_VECTOR(irq);
1138 next:
1139         current_vector += 8;
1140         if (current_vector == SYSCALL_VECTOR)
1141                 goto next;
1142
1143         if (current_vector >= FIRST_SYSTEM_VECTOR) {
1144                 offset++;
1145                 if (!(offset%8))
1146                         return -ENOSPC;
1147                 current_vector = FIRST_DEVICE_VECTOR + offset;
1148         }
1149
1150         vector_irq[current_vector] = irq;
1151         if (irq != AUTO_ASSIGN)
1152                 IO_APIC_VECTOR(irq) = current_vector;
1153
1154         return current_vector;
1155 }
1156
1157 static struct hw_interrupt_type ioapic_level_type;
1158 static struct hw_interrupt_type ioapic_edge_type;
1159
1160 #define IOAPIC_AUTO     -1
1161 #define IOAPIC_EDGE     0
1162 #define IOAPIC_LEVEL    1
1163
1164 static inline void ioapic_register_intr(int irq, int vector, unsigned long trigger)
1165 {
1166         if (use_pci_vector() && !platform_legacy_irq(irq)) {
1167                 if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
1168                                 trigger == IOAPIC_LEVEL)
1169                         irq_desc[vector].handler = &ioapic_level_type;
1170                 else
1171                         irq_desc[vector].handler = &ioapic_edge_type;
1172                 set_intr_gate(vector, interrupt[vector]);
1173         } else  {
1174                 if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
1175                                 trigger == IOAPIC_LEVEL)
1176                         irq_desc[irq].handler = &ioapic_level_type;
1177                 else
1178                         irq_desc[irq].handler = &ioapic_edge_type;
1179                 set_intr_gate(vector, interrupt[irq]);
1180         }
1181 }
1182
1183 static void __init setup_IO_APIC_irqs(void)
1184 {
1185         struct IO_APIC_route_entry entry;
1186         int apic, pin, idx, irq, first_notcon = 1, vector;
1187         unsigned long flags;
1188
1189         apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");
1190
1191         for (apic = 0; apic < nr_ioapics; apic++) {
1192         for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
1193
1194                 /*
1195                  * add it to the IO-APIC irq-routing table:
1196                  */
1197                 memset(&entry,0,sizeof(entry));
1198
1199                 entry.delivery_mode = INT_DELIVERY_MODE;
1200                 entry.dest_mode = INT_DEST_MODE;
1201                 entry.mask = 0;                         /* enable IRQ */
1202                 entry.dest.logical.logical_dest = 
1203                                         cpu_mask_to_apicid(TARGET_CPUS);
1204
1205                 idx = find_irq_entry(apic,pin,mp_INT);
1206                 if (idx == -1) {
1207                         if (first_notcon) {
1208                                 apic_printk(APIC_VERBOSE, KERN_DEBUG
1209                                                 " IO-APIC (apicid-pin) %d-%d",
1210                                                 mp_ioapics[apic].mpc_apicid,
1211                                                 pin);
1212                                 first_notcon = 0;
1213                         } else
1214                                 apic_printk(APIC_VERBOSE, ", %d-%d",
1215                                         mp_ioapics[apic].mpc_apicid, pin);
1216                         continue;
1217                 }
1218
1219                 entry.trigger = irq_trigger(idx);
1220                 entry.polarity = irq_polarity(idx);
1221
1222                 if (irq_trigger(idx)) {
1223                         entry.trigger = 1;
1224                         entry.mask = 1;
1225                 }
1226
1227                 irq = pin_2_irq(idx, apic, pin);
1228                 /*
1229                  * skip adding the timer int on secondary nodes, which causes
1230                  * a small but painful rift in the time-space continuum
1231                  */
1232                 if (multi_timer_check(apic, irq))
1233                         continue;
1234                 else
1235                         add_pin_to_irq(irq, apic, pin);
1236
1237                 if (!apic && !IO_APIC_IRQ(irq))
1238                         continue;
1239
1240                 if (IO_APIC_IRQ(irq)) {
1241                         vector = assign_irq_vector(irq);
1242                         entry.vector = vector;
1243                         ioapic_register_intr(irq, vector, IOAPIC_AUTO);
1244                 
1245                         if (!apic && (irq < 16))
1246                                 disable_8259A_irq(irq);
1247                 }
1248                 spin_lock_irqsave(&ioapic_lock, flags);
1249                 io_apic_write(apic, 0x11+2*pin, *(((int *)&entry)+1));
1250                 io_apic_write(apic, 0x10+2*pin, *(((int *)&entry)+0));
1251                 spin_unlock_irqrestore(&ioapic_lock, flags);
1252         }
1253         }
1254
1255         if (!first_notcon)
1256                 apic_printk(APIC_VERBOSE, " not connected.\n");
1257 }
1258
1259 /*
1260  * Set up the 8259A-master output pin:
1261  */
1262 static void __init setup_ExtINT_IRQ0_pin(unsigned int pin, int vector)
1263 {
1264         struct IO_APIC_route_entry entry;
1265         unsigned long flags;
1266
1267         memset(&entry,0,sizeof(entry));
1268
1269         disable_8259A_irq(0);
1270
1271         /* mask LVT0 */
1272         apic_write_around(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
1273
1274         /*
1275          * We use logical delivery to get the timer IRQ
1276          * to the first CPU.
1277          */
1278         entry.dest_mode = INT_DEST_MODE;
1279         entry.mask = 0;                                 /* unmask IRQ now */
1280         entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS);
1281         entry.delivery_mode = INT_DELIVERY_MODE;
1282         entry.polarity = 0;
1283         entry.trigger = 0;
1284         entry.vector = vector;
1285
1286         /*
1287          * The timer IRQ doesn't have to know that behind the
1288          * scene we have a 8259A-master in AEOI mode ...
1289          */
1290         irq_desc[0].handler = &ioapic_edge_type;
1291
1292         /*
1293          * Add it to the IO-APIC irq-routing table:
1294          */
1295         spin_lock_irqsave(&ioapic_lock, flags);
1296         io_apic_write(0, 0x11+2*pin, *(((int *)&entry)+1));
1297         io_apic_write(0, 0x10+2*pin, *(((int *)&entry)+0));
1298         spin_unlock_irqrestore(&ioapic_lock, flags);
1299
1300         enable_8259A_irq(0);
1301 }
1302
1303 static inline void UNEXPECTED_IO_APIC(void)
1304 {
1305 }
1306
1307 void __init print_IO_APIC(void)
1308 {
1309         int apic, i;
1310         union IO_APIC_reg_00 reg_00;
1311         union IO_APIC_reg_01 reg_01;
1312         union IO_APIC_reg_02 reg_02;
1313         union IO_APIC_reg_03 reg_03;
1314         unsigned long flags;
1315
1316         if (apic_verbosity == APIC_QUIET)
1317                 return;
1318
1319         printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
1320         for (i = 0; i < nr_ioapics; i++)
1321                 printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
1322                        mp_ioapics[i].mpc_apicid, nr_ioapic_registers[i]);
1323
1324         /*
1325          * We are a bit conservative about what we expect.  We have to
1326          * know about every hardware change ASAP.
1327          */
1328         printk(KERN_INFO "testing the IO APIC.......................\n");
1329
1330         for (apic = 0; apic < nr_ioapics; apic++) {
1331
1332         spin_lock_irqsave(&ioapic_lock, flags);
1333         reg_00.raw = io_apic_read(apic, 0);
1334         reg_01.raw = io_apic_read(apic, 1);
1335         if (reg_01.bits.version >= 0x10)
1336                 reg_02.raw = io_apic_read(apic, 2);
1337         if (reg_01.bits.version >= 0x20)
1338                 reg_03.raw = io_apic_read(apic, 3);
1339         spin_unlock_irqrestore(&ioapic_lock, flags);
1340
1341         printk(KERN_DEBUG "IO APIC #%d......\n", mp_ioapics[apic].mpc_apicid);
1342         printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
1343         printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
1344         printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
1345         printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);
1346         if (reg_00.bits.ID >= get_physical_broadcast())
1347                 UNEXPECTED_IO_APIC();
1348         if (reg_00.bits.__reserved_1 || reg_00.bits.__reserved_2)
1349                 UNEXPECTED_IO_APIC();
1350
1351         printk(KERN_DEBUG ".... register #01: %08X\n", reg_01.raw);
1352         printk(KERN_DEBUG ".......     : max redirection entries: %04X\n", reg_01.bits.entries);
1353         if (    (reg_01.bits.entries != 0x0f) && /* older (Neptune) boards */
1354                 (reg_01.bits.entries != 0x17) && /* typical ISA+PCI boards */
1355                 (reg_01.bits.entries != 0x1b) && /* Compaq Proliant boards */
1356                 (reg_01.bits.entries != 0x1f) && /* dual Xeon boards */
1357                 (reg_01.bits.entries != 0x22) && /* bigger Xeon boards */
1358                 (reg_01.bits.entries != 0x2E) &&
1359                 (reg_01.bits.entries != 0x3F)
1360         )
1361                 UNEXPECTED_IO_APIC();
1362
1363         printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
1364         printk(KERN_DEBUG ".......     : IO APIC version: %04X\n", reg_01.bits.version);
1365         if (    (reg_01.bits.version != 0x01) && /* 82489DX IO-APICs */
1366                 (reg_01.bits.version != 0x10) && /* oldest IO-APICs */
1367                 (reg_01.bits.version != 0x11) && /* Pentium/Pro IO-APICs */
1368                 (reg_01.bits.version != 0x13) && /* Xeon IO-APICs */
1369                 (reg_01.bits.version != 0x20)    /* Intel P64H (82806 AA) */
1370         )
1371                 UNEXPECTED_IO_APIC();
1372         if (reg_01.bits.__reserved_1 || reg_01.bits.__reserved_2)
1373                 UNEXPECTED_IO_APIC();
1374
1375         /*
1376          * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
1377          * but the value of reg_02 is read as the previous read register
1378          * value, so ignore it if reg_02 == reg_01.
1379          */
1380         if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
1381                 printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
1382                 printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
1383                 if (reg_02.bits.__reserved_1 || reg_02.bits.__reserved_2)
1384                         UNEXPECTED_IO_APIC();
1385         }
1386
1387         /*
1388          * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
1389          * or reg_03, but the value of reg_0[23] is read as the previous read
1390          * register value, so ignore it if reg_03 == reg_0[12].
1391          */
1392         if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
1393             reg_03.raw != reg_01.raw) {
1394                 printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
1395                 printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
1396                 if (reg_03.bits.__reserved_1)
1397                         UNEXPECTED_IO_APIC();
1398         }
1399
1400         printk(KERN_DEBUG ".... IRQ redirection table:\n");
1401
1402         printk(KERN_DEBUG " NR Log Phy Mask Trig IRR Pol"
1403                           " Stat Dest Deli Vect:   \n");
1404
1405         for (i = 0; i <= reg_01.bits.entries; i++) {
1406                 struct IO_APIC_route_entry entry;
1407
1408                 spin_lock_irqsave(&ioapic_lock, flags);
1409                 *(((int *)&entry)+0) = io_apic_read(apic, 0x10+i*2);
1410                 *(((int *)&entry)+1) = io_apic_read(apic, 0x11+i*2);
1411                 spin_unlock_irqrestore(&ioapic_lock, flags);
1412
1413                 printk(KERN_DEBUG " %02x %03X %02X  ",
1414                         i,
1415                         entry.dest.logical.logical_dest,
1416                         entry.dest.physical.physical_dest
1417                 );
1418
1419                 printk("%1d    %1d    %1d   %1d   %1d    %1d    %1d    %02X\n",
1420                         entry.mask,
1421                         entry.trigger,
1422                         entry.irr,
1423                         entry.polarity,
1424                         entry.delivery_status,
1425                         entry.dest_mode,
1426                         entry.delivery_mode,
1427                         entry.vector
1428                 );
1429         }
1430         }
1431         if (use_pci_vector())
1432                 printk(KERN_INFO "Using vector-based indexing\n");
1433         printk(KERN_DEBUG "IRQ to pin mappings:\n");
1434         for (i = 0; i < NR_IRQS; i++) {
1435                 struct irq_pin_list *entry = irq_2_pin + i;
1436                 if (entry->pin < 0)
1437                         continue;
1438                 if (use_pci_vector() && !platform_legacy_irq(i))
1439                         printk(KERN_DEBUG "IRQ%d ", IO_APIC_VECTOR(i));
1440                 else
1441                         printk(KERN_DEBUG "IRQ%d ", i);
1442                 for (;;) {
1443                         printk("-> %d:%d", entry->apic, entry->pin);
1444                         if (!entry->next)
1445                                 break;
1446                         entry = irq_2_pin + entry->next;
1447                 }
1448                 printk("\n");
1449         }
1450
1451         printk(KERN_INFO ".................................... done.\n");
1452
1453         return;
1454 }
1455
1456 #if 0
1457
1458 static void print_APIC_bitfield (int base)
1459 {
1460         unsigned int v;
1461         int i, j;
1462
1463         if (apic_verbosity == APIC_QUIET)
1464                 return;
1465
1466         printk(KERN_DEBUG "0123456789abcdef0123456789abcdef\n" KERN_DEBUG);
1467         for (i = 0; i < 8; i++) {
1468                 v = apic_read(base + i*0x10);
1469                 for (j = 0; j < 32; j++) {
1470                         if (v & (1<<j))
1471                                 printk("1");
1472                         else
1473                                 printk("0");
1474                 }
1475                 printk("\n");
1476         }
1477 }
1478
1479 void /*__init*/ print_local_APIC(void * dummy)
1480 {
1481         unsigned int v, ver, maxlvt;
1482
1483         if (apic_verbosity == APIC_QUIET)
1484                 return;
1485
1486         printk("\n" KERN_DEBUG "printing local APIC contents on CPU#%d/%d:\n",
1487                 smp_processor_id(), hard_smp_processor_id());
1488         v = apic_read(APIC_ID);
1489         printk(KERN_INFO "... APIC ID:      %08x (%01x)\n", v, GET_APIC_ID(v));
1490         v = apic_read(APIC_LVR);
1491         printk(KERN_INFO "... APIC VERSION: %08x\n", v);
1492         ver = GET_APIC_VERSION(v);
1493         maxlvt = get_maxlvt();
1494
1495         v = apic_read(APIC_TASKPRI);
1496         printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
1497
1498         if (APIC_INTEGRATED(ver)) {                     /* !82489DX */
1499                 v = apic_read(APIC_ARBPRI);
1500                 printk(KERN_DEBUG "... APIC ARBPRI: %08x (%02x)\n", v,
1501                         v & APIC_ARBPRI_MASK);
1502                 v = apic_read(APIC_PROCPRI);
1503                 printk(KERN_DEBUG "... APIC PROCPRI: %08x\n", v);
1504         }
1505
1506         v = apic_read(APIC_EOI);
1507         printk(KERN_DEBUG "... APIC EOI: %08x\n", v);
1508         v = apic_read(APIC_RRR);
1509         printk(KERN_DEBUG "... APIC RRR: %08x\n", v);
1510         v = apic_read(APIC_LDR);
1511         printk(KERN_DEBUG "... APIC LDR: %08x\n", v);
1512         v = apic_read(APIC_DFR);
1513         printk(KERN_DEBUG "... APIC DFR: %08x\n", v);
1514         v = apic_read(APIC_SPIV);
1515         printk(KERN_DEBUG "... APIC SPIV: %08x\n", v);
1516
1517         printk(KERN_DEBUG "... APIC ISR field:\n");
1518         print_APIC_bitfield(APIC_ISR);
1519         printk(KERN_DEBUG "... APIC TMR field:\n");
1520         print_APIC_bitfield(APIC_TMR);
1521         printk(KERN_DEBUG "... APIC IRR field:\n");
1522         print_APIC_bitfield(APIC_IRR);
1523
1524         if (APIC_INTEGRATED(ver)) {             /* !82489DX */
1525                 if (maxlvt > 3)         /* Due to the Pentium erratum 3AP. */
1526                         apic_write(APIC_ESR, 0);
1527                 v = apic_read(APIC_ESR);
1528                 printk(KERN_DEBUG "... APIC ESR: %08x\n", v);
1529         }
1530
1531         v = apic_read(APIC_ICR);
1532         printk(KERN_DEBUG "... APIC ICR: %08x\n", v);
1533         v = apic_read(APIC_ICR2);
1534         printk(KERN_DEBUG "... APIC ICR2: %08x\n", v);
1535
1536         v = apic_read(APIC_LVTT);
1537         printk(KERN_DEBUG "... APIC LVTT: %08x\n", v);
1538
1539         if (maxlvt > 3) {                       /* PC is LVT#4. */
1540                 v = apic_read(APIC_LVTPC);
1541                 printk(KERN_DEBUG "... APIC LVTPC: %08x\n", v);
1542         }
1543         v = apic_read(APIC_LVT0);
1544         printk(KERN_DEBUG "... APIC LVT0: %08x\n", v);
1545         v = apic_read(APIC_LVT1);
1546         printk(KERN_DEBUG "... APIC LVT1: %08x\n", v);
1547
1548         if (maxlvt > 2) {                       /* ERR is LVT#3. */
1549                 v = apic_read(APIC_LVTERR);
1550                 printk(KERN_DEBUG "... APIC LVTERR: %08x\n", v);
1551         }
1552
1553         v = apic_read(APIC_TMICT);
1554         printk(KERN_DEBUG "... APIC TMICT: %08x\n", v);
1555         v = apic_read(APIC_TMCCT);
1556         printk(KERN_DEBUG "... APIC TMCCT: %08x\n", v);
1557         v = apic_read(APIC_TDCR);
1558         printk(KERN_DEBUG "... APIC TDCR: %08x\n", v);
1559         printk("\n");
1560 }
1561
1562 void print_all_local_APICs (void)
1563 {
1564         on_each_cpu(print_local_APIC, NULL, 1, 1);
1565 }
1566
1567 void /*__init*/ print_PIC(void)
1568 {
1569         extern spinlock_t i8259A_lock;
1570         unsigned int v;
1571         unsigned long flags;
1572
1573         if (apic_verbosity == APIC_QUIET)
1574                 return;
1575
1576         printk(KERN_DEBUG "\nprinting PIC contents\n");
1577
1578         spin_lock_irqsave(&i8259A_lock, flags);
1579
1580         v = inb(0xa1) << 8 | inb(0x21);
1581         printk(KERN_DEBUG "... PIC  IMR: %04x\n", v);
1582
1583         v = inb(0xa0) << 8 | inb(0x20);
1584         printk(KERN_DEBUG "... PIC  IRR: %04x\n", v);
1585
1586         outb(0x0b,0xa0);
1587         outb(0x0b,0x20);
1588         v = inb(0xa0) << 8 | inb(0x20);
1589         outb(0x0a,0xa0);
1590         outb(0x0a,0x20);
1591
1592         spin_unlock_irqrestore(&i8259A_lock, flags);
1593
1594         printk(KERN_DEBUG "... PIC  ISR: %04x\n", v);
1595
1596         v = inb(0x4d1) << 8 | inb(0x4d0);
1597         printk(KERN_DEBUG "... PIC ELCR: %04x\n", v);
1598 }
1599
1600 #endif  /*  0  */
1601
1602 static void __init enable_IO_APIC(void)
1603 {
1604         union IO_APIC_reg_01 reg_01;
1605         int i;
1606         unsigned long flags;
1607
1608         for (i = 0; i < PIN_MAP_SIZE; i++) {
1609                 irq_2_pin[i].pin = -1;
1610                 irq_2_pin[i].next = 0;
1611         }
1612         if (!pirqs_enabled)
1613                 for (i = 0; i < MAX_PIRQS; i++)
1614                         pirq_entries[i] = -1;
1615
1616         /*
1617          * The number of IO-APIC IRQ registers (== #pins):
1618          */
1619         for (i = 0; i < nr_ioapics; i++) {
1620                 spin_lock_irqsave(&ioapic_lock, flags);
1621                 reg_01.raw = io_apic_read(i, 1);
1622                 spin_unlock_irqrestore(&ioapic_lock, flags);
1623                 nr_ioapic_registers[i] = reg_01.bits.entries+1;
1624         }
1625
1626         /*
1627          * Do not trust the IO-APIC being empty at bootup
1628          */
1629         clear_IO_APIC();
1630 }
1631
1632 /*
1633  * Not an __init, needed by the reboot code
1634  */
1635 void disable_IO_APIC(void)
1636 {
1637         int pin;
1638         /*
1639          * Clear the IO-APIC before rebooting:
1640          */
1641         clear_IO_APIC();
1642
1643         /*
1644          * If the i82559 is routed through an IOAPIC
1645          * Put that IOAPIC in virtual wire mode
1646          * so legacy interrups can be delivered.
1647          */
1648         pin = find_isa_irq_pin(0, mp_ExtINT);
1649         if (pin != -1) {
1650                 struct IO_APIC_route_entry entry;
1651                 unsigned long flags;
1652
1653                 memset(&entry, 0, sizeof(entry));
1654                 entry.mask            = 0; /* Enabled */
1655                 entry.trigger         = 0; /* Edge */
1656                 entry.irr             = 0;
1657                 entry.polarity        = 0; /* High */
1658                 entry.delivery_status = 0;
1659                 entry.dest_mode       = 0; /* Physical */
1660                 entry.delivery_mode   = 7; /* ExtInt */
1661                 entry.vector          = 0;
1662                 entry.dest.physical.physical_dest = 0;
1663
1664
1665                 /*
1666                  * Add it to the IO-APIC irq-routing table:
1667                  */
1668                 spin_lock_irqsave(&ioapic_lock, flags);
1669                 io_apic_write(0, 0x11+2*pin, *(((int *)&entry)+1));
1670                 io_apic_write(0, 0x10+2*pin, *(((int *)&entry)+0));
1671                 spin_unlock_irqrestore(&ioapic_lock, flags);
1672         }
1673         disconnect_bsp_APIC(pin != -1);
1674 }
1675
1676 /*
1677  * function to set the IO-APIC physical IDs based on the
1678  * values stored in the MPC table.
1679  *
1680  * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
1681  */
1682
1683 #ifndef CONFIG_X86_NUMAQ
1684 static void __init setup_ioapic_ids_from_mpc(void)
1685 {
1686         union IO_APIC_reg_00 reg_00;
1687         physid_mask_t phys_id_present_map;
1688         int apic;
1689         int i;
1690         unsigned char old_id;
1691         unsigned long flags;
1692
1693         /*
1694          * Don't check I/O APIC IDs for xAPIC systems.  They have
1695          * no meaning without the serial APIC bus.
1696          */
1697         if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && boot_cpu_data.x86 < 15))
1698                 return;
1699         /*
1700          * This is broken; anything with a real cpu count has to
1701          * circumvent this idiocy regardless.
1702          */
1703         phys_id_present_map = ioapic_phys_id_map(phys_cpu_present_map);
1704
1705         /*
1706          * Set the IOAPIC ID to the value stored in the MPC table.
1707          */
1708         for (apic = 0; apic < nr_ioapics; apic++) {
1709
1710                 /* Read the register 0 value */
1711                 spin_lock_irqsave(&ioapic_lock, flags);
1712                 reg_00.raw = io_apic_read(apic, 0);
1713                 spin_unlock_irqrestore(&ioapic_lock, flags);
1714                 
1715                 old_id = mp_ioapics[apic].mpc_apicid;
1716
1717                 if (mp_ioapics[apic].mpc_apicid >= get_physical_broadcast()) {
1718                         printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
1719                                 apic, mp_ioapics[apic].mpc_apicid);
1720                         printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1721                                 reg_00.bits.ID);
1722                         mp_ioapics[apic].mpc_apicid = reg_00.bits.ID;
1723                 }
1724
1725                 /*
1726                  * Sanity check, is the ID really free? Every APIC in a
1727                  * system must have a unique ID or we get lots of nice
1728                  * 'stuck on smp_invalidate_needed IPI wait' messages.
1729                  */
1730                 if (check_apicid_used(phys_id_present_map,
1731                                         mp_ioapics[apic].mpc_apicid)) {
1732                         printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
1733                                 apic, mp_ioapics[apic].mpc_apicid);
1734                         for (i = 0; i < get_physical_broadcast(); i++)
1735                                 if (!physid_isset(i, phys_id_present_map))
1736                                         break;
1737                         if (i >= get_physical_broadcast())
1738                                 panic("Max APIC ID exceeded!\n");
1739                         printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1740                                 i);
1741                         physid_set(i, phys_id_present_map);
1742                         mp_ioapics[apic].mpc_apicid = i;
1743                 } else {
1744                         physid_mask_t tmp;
1745                         tmp = apicid_to_cpu_present(mp_ioapics[apic].mpc_apicid);
1746                         apic_printk(APIC_VERBOSE, "Setting %d in the "
1747                                         "phys_id_present_map\n",
1748                                         mp_ioapics[apic].mpc_apicid);
1749                         physids_or(phys_id_present_map, phys_id_present_map, tmp);
1750                 }
1751
1752
1753                 /*
1754                  * We need to adjust the IRQ routing table
1755                  * if the ID changed.
1756                  */
1757                 if (old_id != mp_ioapics[apic].mpc_apicid)
1758                         for (i = 0; i < mp_irq_entries; i++)
1759                                 if (mp_irqs[i].mpc_dstapic == old_id)
1760                                         mp_irqs[i].mpc_dstapic
1761                                                 = mp_ioapics[apic].mpc_apicid;
1762
1763                 /*
1764                  * Read the right value from the MPC table and
1765                  * write it into the ID register.
1766                  */
1767                 apic_printk(APIC_VERBOSE, KERN_INFO
1768                         "...changing IO-APIC physical APIC ID to %d ...",
1769                         mp_ioapics[apic].mpc_apicid);
1770
1771                 reg_00.bits.ID = mp_ioapics[apic].mpc_apicid;
1772                 spin_lock_irqsave(&ioapic_lock, flags);
1773                 io_apic_write(apic, 0, reg_00.raw);
1774                 spin_unlock_irqrestore(&ioapic_lock, flags);
1775
1776                 /*
1777                  * Sanity check
1778                  */
1779                 spin_lock_irqsave(&ioapic_lock, flags);
1780                 reg_00.raw = io_apic_read(apic, 0);
1781                 spin_unlock_irqrestore(&ioapic_lock, flags);
1782                 if (reg_00.bits.ID != mp_ioapics[apic].mpc_apicid)
1783                         printk("could not set ID!\n");
1784                 else
1785                         apic_printk(APIC_VERBOSE, " ok.\n");
1786         }
1787 }
1788 #else
1789 static void __init setup_ioapic_ids_from_mpc(void) { }
1790 #endif
1791
1792 /*
1793  * There is a nasty bug in some older SMP boards, their mptable lies
1794  * about the timer IRQ. We do the following to work around the situation:
1795  *
1796  *      - timer IRQ defaults to IO-APIC IRQ
1797  *      - if this function detects that timer IRQs are defunct, then we fall
1798  *        back to ISA timer IRQs
1799  */
1800 static int __init timer_irq_works(void)
1801 {
1802         unsigned long t1 = jiffies;
1803
1804         local_irq_enable();
1805         /* Let ten ticks pass... */
1806         mdelay((10 * 1000) / HZ);
1807
1808         /*
1809          * Expect a few ticks at least, to be sure some possible
1810          * glue logic does not lock up after one or two first
1811          * ticks in a non-ExtINT mode.  Also the local APIC
1812          * might have cached one ExtINT interrupt.  Finally, at
1813          * least one tick may be lost due to delays.
1814          */
1815         if (jiffies - t1 > 4)
1816                 return 1;
1817
1818         return 0;
1819 }
1820
1821 /*
1822  * In the SMP+IOAPIC case it might happen that there are an unspecified
1823  * number of pending IRQ events unhandled. These cases are very rare,
1824  * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
1825  * better to do it this way as thus we do not have to be aware of
1826  * 'pending' interrupts in the IRQ path, except at this point.
1827  */
1828 /*
1829  * Edge triggered needs to resend any interrupt
1830  * that was delayed but this is now handled in the device
1831  * independent code.
1832  */
1833
1834 /*
1835  * Starting up a edge-triggered IO-APIC interrupt is
1836  * nasty - we need to make sure that we get the edge.
1837  * If it is already asserted for some reason, we need
1838  * return 1 to indicate that is was pending.
1839  *
1840  * This is not complete - we should be able to fake
1841  * an edge even if it isn't on the 8259A...
1842  */
1843 static unsigned int startup_edge_ioapic_irq(unsigned int irq)
1844 {
1845         int was_pending = 0;
1846         unsigned long flags;
1847
1848         spin_lock_irqsave(&ioapic_lock, flags);
1849         if (irq < 16) {
1850                 disable_8259A_irq(irq);
1851                 if (i8259A_irq_pending(irq))
1852                         was_pending = 1;
1853         }
1854         __unmask_IO_APIC_irq(irq);
1855         spin_unlock_irqrestore(&ioapic_lock, flags);
1856
1857         return was_pending;
1858 }
1859
1860 /*
1861  * Once we have recorded IRQ_PENDING already, we can mask the
1862  * interrupt for real. This prevents IRQ storms from unhandled
1863  * devices.
1864  */
1865 static void ack_edge_ioapic_irq(unsigned int irq)
1866 {
1867         move_irq(irq);
1868         if ((irq_desc[irq].status & (IRQ_PENDING | IRQ_DISABLED))
1869                                         == (IRQ_PENDING | IRQ_DISABLED))
1870                 mask_IO_APIC_irq(irq);
1871         ack_APIC_irq();
1872 }
1873
1874 /*
1875  * Level triggered interrupts can just be masked,
1876  * and shutting down and starting up the interrupt
1877  * is the same as enabling and disabling them -- except
1878  * with a startup need to return a "was pending" value.
1879  *
1880  * Level triggered interrupts are special because we
1881  * do not touch any IO-APIC register while handling
1882  * them. We ack the APIC in the end-IRQ handler, not
1883  * in the start-IRQ-handler. Protection against reentrance
1884  * from the same interrupt is still provided, both by the
1885  * generic IRQ layer and by the fact that an unacked local
1886  * APIC does not accept IRQs.
1887  */
1888 static unsigned int startup_level_ioapic_irq (unsigned int irq)
1889 {
1890         unmask_IO_APIC_irq(irq);
1891
1892         return 0; /* don't check for pending */
1893 }
1894
1895 static void end_level_ioapic_irq (unsigned int irq)
1896 {
1897         unsigned long v;
1898         int i;
1899
1900         move_irq(irq);
1901 /*
1902  * It appears there is an erratum which affects at least version 0x11
1903  * of I/O APIC (that's the 82093AA and cores integrated into various
1904  * chipsets).  Under certain conditions a level-triggered interrupt is
1905  * erroneously delivered as edge-triggered one but the respective IRR
1906  * bit gets set nevertheless.  As a result the I/O unit expects an EOI
1907  * message but it will never arrive and further interrupts are blocked
1908  * from the source.  The exact reason is so far unknown, but the
1909  * phenomenon was observed when two consecutive interrupt requests
1910  * from a given source get delivered to the same CPU and the source is
1911  * temporarily disabled in between.
1912  *
1913  * A workaround is to simulate an EOI message manually.  We achieve it
1914  * by setting the trigger mode to edge and then to level when the edge
1915  * trigger mode gets detected in the TMR of a local APIC for a
1916  * level-triggered interrupt.  We mask the source for the time of the
1917  * operation to prevent an edge-triggered interrupt escaping meanwhile.
1918  * The idea is from Manfred Spraul.  --macro
1919  */
1920         i = IO_APIC_VECTOR(irq);
1921
1922         v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
1923
1924         ack_APIC_irq();
1925
1926         if (!(v & (1 << (i & 0x1f)))) {
1927                 atomic_inc(&irq_mis_count);
1928                 spin_lock(&ioapic_lock);
1929                 __mask_and_edge_IO_APIC_irq(irq);
1930                 __unmask_and_level_IO_APIC_irq(irq);
1931                 spin_unlock(&ioapic_lock);
1932         }
1933 }
1934
1935 #ifdef CONFIG_PCI_MSI
1936 static unsigned int startup_edge_ioapic_vector(unsigned int vector)
1937 {
1938         int irq = vector_to_irq(vector);
1939
1940         return startup_edge_ioapic_irq(irq);
1941 }
1942
1943 static void ack_edge_ioapic_vector(unsigned int vector)
1944 {
1945         int irq = vector_to_irq(vector);
1946
1947         ack_edge_ioapic_irq(irq);
1948 }
1949
1950 static unsigned int startup_level_ioapic_vector (unsigned int vector)
1951 {
1952         int irq = vector_to_irq(vector);
1953
1954         return startup_level_ioapic_irq (irq);
1955 }
1956
1957 static void end_level_ioapic_vector (unsigned int vector)
1958 {
1959         int irq = vector_to_irq(vector);
1960
1961         end_level_ioapic_irq(irq);
1962 }
1963
1964 static void mask_IO_APIC_vector (unsigned int vector)
1965 {
1966         int irq = vector_to_irq(vector);
1967
1968         mask_IO_APIC_irq(irq);
1969 }
1970
1971 static void unmask_IO_APIC_vector (unsigned int vector)
1972 {
1973         int irq = vector_to_irq(vector);
1974
1975         unmask_IO_APIC_irq(irq);
1976 }
1977
1978 static void set_ioapic_affinity_vector (unsigned int vector,
1979                                         cpumask_t cpu_mask)
1980 {
1981         int irq = vector_to_irq(vector);
1982
1983         set_ioapic_affinity_irq(irq, cpu_mask);
1984 }
1985 #endif
1986
1987 /*
1988  * Level and edge triggered IO-APIC interrupts need different handling,
1989  * so we use two separate IRQ descriptors. Edge triggered IRQs can be
1990  * handled with the level-triggered descriptor, but that one has slightly
1991  * more overhead. Level-triggered interrupts cannot be handled with the
1992  * edge-triggered handler, without risking IRQ storms and other ugly
1993  * races.
1994  */
1995 static struct hw_interrupt_type ioapic_edge_type = {
1996         .typename       = "IO-APIC-edge",
1997         .startup        = startup_edge_ioapic,
1998         .shutdown       = shutdown_edge_ioapic,
1999         .enable         = enable_edge_ioapic,
2000         .disable        = disable_edge_ioapic,
2001         .ack            = ack_edge_ioapic,
2002         .end            = end_edge_ioapic,
2003         .set_affinity   = set_ioapic_affinity,
2004 };
2005
2006 static struct hw_interrupt_type ioapic_level_type = {
2007         .typename       = "IO-APIC-level",
2008         .startup        = startup_level_ioapic,
2009         .shutdown       = shutdown_level_ioapic,
2010         .enable         = enable_level_ioapic,
2011         .disable        = disable_level_ioapic,
2012         .ack            = mask_and_ack_level_ioapic,
2013         .end            = end_level_ioapic,
2014         .set_affinity   = set_ioapic_affinity,
2015 };
2016
2017 static inline void init_IO_APIC_traps(void)
2018 {
2019         int irq;
2020
2021         /*
2022          * NOTE! The local APIC isn't very good at handling
2023          * multiple interrupts at the same interrupt level.
2024          * As the interrupt level is determined by taking the
2025          * vector number and shifting that right by 4, we
2026          * want to spread these out a bit so that they don't
2027          * all fall in the same interrupt level.
2028          *
2029          * Also, we've got to be careful not to trash gate
2030          * 0x80, because int 0x80 is hm, kind of importantish. ;)
2031          */
2032         for (irq = 0; irq < NR_IRQS ; irq++) {
2033                 int tmp = irq;
2034                 if (use_pci_vector()) {
2035                         if (!platform_legacy_irq(tmp))
2036                                 if ((tmp = vector_to_irq(tmp)) == -1)
2037                                         continue;
2038                 }
2039                 if (IO_APIC_IRQ(tmp) && !IO_APIC_VECTOR(tmp)) {
2040                         /*
2041                          * Hmm.. We don't have an entry for this,
2042                          * so default to an old-fashioned 8259
2043                          * interrupt if we can..
2044                          */
2045                         if (irq < 16)
2046                                 make_8259A_irq(irq);
2047                         else
2048                                 /* Strange. Oh, well.. */
2049                                 irq_desc[irq].handler = &no_irq_type;
2050                 }
2051         }
2052 }
2053
2054 static void enable_lapic_irq (unsigned int irq)
2055 {
2056         unsigned long v;
2057
2058         v = apic_read(APIC_LVT0);
2059         apic_write_around(APIC_LVT0, v & ~APIC_LVT_MASKED);
2060 }
2061
2062 static void disable_lapic_irq (unsigned int irq)
2063 {
2064         unsigned long v;
2065
2066         v = apic_read(APIC_LVT0);
2067         apic_write_around(APIC_LVT0, v | APIC_LVT_MASKED);
2068 }
2069
2070 static void ack_lapic_irq (unsigned int irq)
2071 {
2072         ack_APIC_irq();
2073 }
2074
2075 static void end_lapic_irq (unsigned int i) { /* nothing */ }
2076
2077 static struct hw_interrupt_type lapic_irq_type = {
2078         .typename       = "local-APIC-edge",
2079         .startup        = NULL, /* startup_irq() not used for IRQ0 */
2080         .shutdown       = NULL, /* shutdown_irq() not used for IRQ0 */
2081         .enable         = enable_lapic_irq,
2082         .disable        = disable_lapic_irq,
2083         .ack            = ack_lapic_irq,
2084         .end            = end_lapic_irq
2085 };
2086
2087 static void setup_nmi (void)
2088 {
2089         /*
2090          * Dirty trick to enable the NMI watchdog ...
2091          * We put the 8259A master into AEOI mode and
2092          * unmask on all local APICs LVT0 as NMI.
2093          *
2094          * The idea to use the 8259A in AEOI mode ('8259A Virtual Wire')
2095          * is from Maciej W. Rozycki - so we do not have to EOI from
2096          * the NMI handler or the timer interrupt.
2097          */ 
2098         apic_printk(APIC_VERBOSE, KERN_INFO "activating NMI Watchdog ...");
2099
2100         on_each_cpu(enable_NMI_through_LVT0, NULL, 1, 1);
2101
2102         apic_printk(APIC_VERBOSE, " done.\n");
2103 }
2104
2105 /*
2106  * This looks a bit hackish but it's about the only one way of sending
2107  * a few INTA cycles to 8259As and any associated glue logic.  ICR does
2108  * not support the ExtINT mode, unfortunately.  We need to send these
2109  * cycles as some i82489DX-based boards have glue logic that keeps the
2110  * 8259A interrupt line asserted until INTA.  --macro
2111  */
2112 static inline void unlock_ExtINT_logic(void)
2113 {
2114         int pin, i;
2115         struct IO_APIC_route_entry entry0, entry1;
2116         unsigned char save_control, save_freq_select;
2117         unsigned long flags;
2118
2119         pin = find_isa_irq_pin(8, mp_INT);
2120         if (pin == -1)
2121                 return;
2122
2123         spin_lock_irqsave(&ioapic_lock, flags);
2124         *(((int *)&entry0) + 1) = io_apic_read(0, 0x11 + 2 * pin);
2125         *(((int *)&entry0) + 0) = io_apic_read(0, 0x10 + 2 * pin);
2126         spin_unlock_irqrestore(&ioapic_lock, flags);
2127         clear_IO_APIC_pin(0, pin);
2128
2129         memset(&entry1, 0, sizeof(entry1));
2130
2131         entry1.dest_mode = 0;                   /* physical delivery */
2132         entry1.mask = 0;                        /* unmask IRQ now */
2133         entry1.dest.physical.physical_dest = hard_smp_processor_id();
2134         entry1.delivery_mode = dest_ExtINT;
2135         entry1.polarity = entry0.polarity;
2136         entry1.trigger = 0;
2137         entry1.vector = 0;
2138
2139         spin_lock_irqsave(&ioapic_lock, flags);
2140         io_apic_write(0, 0x11 + 2 * pin, *(((int *)&entry1) + 1));
2141         io_apic_write(0, 0x10 + 2 * pin, *(((int *)&entry1) + 0));
2142         spin_unlock_irqrestore(&ioapic_lock, flags);
2143
2144         save_control = CMOS_READ(RTC_CONTROL);
2145         save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
2146         CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
2147                    RTC_FREQ_SELECT);
2148         CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);
2149
2150         i = 100;
2151         while (i-- > 0) {
2152                 mdelay(10);
2153                 if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
2154                         i -= 10;
2155         }
2156
2157         CMOS_WRITE(save_control, RTC_CONTROL);
2158         CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
2159         clear_IO_APIC_pin(0, pin);
2160
2161         spin_lock_irqsave(&ioapic_lock, flags);
2162         io_apic_write(0, 0x11 + 2 * pin, *(((int *)&entry0) + 1));
2163         io_apic_write(0, 0x10 + 2 * pin, *(((int *)&entry0) + 0));
2164         spin_unlock_irqrestore(&ioapic_lock, flags);
2165 }
2166
2167 /*
2168  * This code may look a bit paranoid, but it's supposed to cooperate with
2169  * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
2170  * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
2171  * fanatically on his truly buggy board.
2172  */
2173 static inline void check_timer(void)
2174 {
2175         int pin1, pin2;
2176         int vector;
2177
2178         /*
2179          * get/set the timer IRQ vector:
2180          */
2181         disable_8259A_irq(0);
2182         vector = assign_irq_vector(0);
2183         set_intr_gate(vector, interrupt[0]);
2184
2185         /*
2186          * Subtle, code in do_timer_interrupt() expects an AEOI
2187          * mode for the 8259A whenever interrupts are routed
2188          * through I/O APICs.  Also IRQ0 has to be enabled in
2189          * the 8259A which implies the virtual wire has to be
2190          * disabled in the local APIC.
2191          */
2192         apic_write_around(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
2193         init_8259A(1);
2194         timer_ack = 1;
2195         enable_8259A_irq(0);
2196
2197         pin1 = find_isa_irq_pin(0, mp_INT);
2198         pin2 = find_isa_irq_pin(0, mp_ExtINT);
2199
2200         printk(KERN_INFO "..TIMER: vector=0x%02X pin1=%d pin2=%d\n", vector, pin1, pin2);
2201
2202         if (pin1 != -1) {
2203                 /*
2204                  * Ok, does IRQ0 through the IOAPIC work?
2205                  */
2206                 unmask_IO_APIC_irq(0);
2207                 if (timer_irq_works()) {
2208                         if (nmi_watchdog == NMI_IO_APIC) {
2209                                 disable_8259A_irq(0);
2210                                 setup_nmi();
2211                                 enable_8259A_irq(0);
2212                         }
2213                         return;
2214                 }
2215                 clear_IO_APIC_pin(0, pin1);
2216                 printk(KERN_ERR "..MP-BIOS bug: 8254 timer not connected to IO-APIC\n");
2217         }
2218
2219         printk(KERN_INFO "...trying to set up timer (IRQ0) through the 8259A ... ");
2220         if (pin2 != -1) {
2221                 printk("\n..... (found pin %d) ...", pin2);
2222                 /*
2223                  * legacy devices should be connected to IO APIC #0
2224                  */
2225                 setup_ExtINT_IRQ0_pin(pin2, vector);
2226                 if (timer_irq_works()) {
2227                         printk("works.\n");
2228                         if (pin1 != -1)
2229                                 replace_pin_at_irq(0, 0, pin1, 0, pin2);
2230                         else
2231                                 add_pin_to_irq(0, 0, pin2);
2232                         if (nmi_watchdog == NMI_IO_APIC) {
2233                                 setup_nmi();
2234                         }
2235                         return;
2236                 }
2237                 /*
2238                  * Cleanup, just in case ...
2239                  */
2240                 clear_IO_APIC_pin(0, pin2);
2241         }
2242         printk(" failed.\n");
2243
2244         if (nmi_watchdog == NMI_IO_APIC) {
2245                 printk(KERN_WARNING "timer doesn't work through the IO-APIC - disabling NMI Watchdog!\n");
2246                 nmi_watchdog = 0;
2247         }
2248
2249         printk(KERN_INFO "...trying to set up timer as Virtual Wire IRQ...");
2250
2251         disable_8259A_irq(0);
2252         irq_desc[0].handler = &lapic_irq_type;
2253         apic_write_around(APIC_LVT0, APIC_DM_FIXED | vector);   /* Fixed mode */
2254         enable_8259A_irq(0);
2255
2256         if (timer_irq_works()) {
2257                 printk(" works.\n");
2258                 return;
2259         }
2260         apic_write_around(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | vector);
2261         printk(" failed.\n");
2262
2263         printk(KERN_INFO "...trying to set up timer as ExtINT IRQ...");
2264
2265         timer_ack = 0;
2266         init_8259A(0);
2267         make_8259A_irq(0);
2268         apic_write_around(APIC_LVT0, APIC_DM_EXTINT);
2269
2270         unlock_ExtINT_logic();
2271
2272         if (timer_irq_works()) {
2273                 printk(" works.\n");
2274                 return;
2275         }
2276         printk(" failed :(.\n");
2277         panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
2278                 "report.  Then try booting with the 'noapic' option");
2279 }
2280
2281 /*
2282  *
2283  * IRQ's that are handled by the PIC in the MPS IOAPIC case.
2284  * - IRQ2 is the cascade IRQ, and cannot be a io-apic IRQ.
2285  *   Linux doesn't really care, as it's not actually used
2286  *   for any interrupt handling anyway.
2287  */
2288 #define PIC_IRQS        (1 << PIC_CASCADE_IR)
2289
2290 void __init setup_IO_APIC(void)
2291 {
2292         enable_IO_APIC();
2293
2294         if (acpi_ioapic)
2295                 io_apic_irqs = ~0;      /* all IRQs go through IOAPIC */
2296         else
2297                 io_apic_irqs = ~PIC_IRQS;
2298
2299         printk("ENABLING IO-APIC IRQs\n");
2300
2301         /*
2302          * Set up IO-APIC IRQ routing.
2303          */
2304         if (!acpi_ioapic)
2305                 setup_ioapic_ids_from_mpc();
2306         sync_Arb_IDs();
2307         setup_IO_APIC_irqs();
2308         init_IO_APIC_traps();
2309         check_timer();
2310         if (!acpi_ioapic)
2311                 print_IO_APIC();
2312 }
2313
2314 /*
2315  *      Called after all the initialization is done. If we didnt find any
2316  *      APIC bugs then we can allow the modify fast path
2317  */
2318  
2319 static int __init io_apic_bug_finalize(void)
2320 {
2321         if(sis_apic_bug == -1)
2322                 sis_apic_bug = 0;
2323         return 0;
2324 }
2325
2326 late_initcall(io_apic_bug_finalize);
2327
2328 struct sysfs_ioapic_data {
2329         struct sys_device dev;
2330         struct IO_APIC_route_entry entry[0];
2331 };
2332 static struct sysfs_ioapic_data * mp_ioapic_data[MAX_IO_APICS];
2333
2334 static int ioapic_suspend(struct sys_device *dev, pm_message_t state)
2335 {
2336         struct IO_APIC_route_entry *entry;
2337         struct sysfs_ioapic_data *data;
2338         unsigned long flags;
2339         int i;
2340         
2341         data = container_of(dev, struct sysfs_ioapic_data, dev);
2342         entry = data->entry;
2343         spin_lock_irqsave(&ioapic_lock, flags);
2344         for (i = 0; i < nr_ioapic_registers[dev->id]; i ++, entry ++ ) {
2345                 *(((int *)entry) + 1) = io_apic_read(dev->id, 0x11 + 2 * i);
2346                 *(((int *)entry) + 0) = io_apic_read(dev->id, 0x10 + 2 * i);
2347         }
2348         spin_unlock_irqrestore(&ioapic_lock, flags);
2349
2350         return 0;
2351 }
2352
2353 static int ioapic_resume(struct sys_device *dev)
2354 {
2355         struct IO_APIC_route_entry *entry;
2356         struct sysfs_ioapic_data *data;
2357         unsigned long flags;
2358         union IO_APIC_reg_00 reg_00;
2359         int i;
2360         
2361         data = container_of(dev, struct sysfs_ioapic_data, dev);
2362         entry = data->entry;
2363
2364         spin_lock_irqsave(&ioapic_lock, flags);
2365         reg_00.raw = io_apic_read(dev->id, 0);
2366         if (reg_00.bits.ID != mp_ioapics[dev->id].mpc_apicid) {
2367                 reg_00.bits.ID = mp_ioapics[dev->id].mpc_apicid;
2368                 io_apic_write(dev->id, 0, reg_00.raw);
2369         }
2370         for (i = 0; i < nr_ioapic_registers[dev->id]; i ++, entry ++ ) {
2371                 io_apic_write(dev->id, 0x11+2*i, *(((int *)entry)+1));
2372                 io_apic_write(dev->id, 0x10+2*i, *(((int *)entry)+0));
2373         }
2374         spin_unlock_irqrestore(&ioapic_lock, flags);
2375
2376         return 0;
2377 }
2378
2379 static struct sysdev_class ioapic_sysdev_class = {
2380         set_kset_name("ioapic"),
2381         .suspend = ioapic_suspend,
2382         .resume = ioapic_resume,
2383 };
2384
2385 static int __init ioapic_init_sysfs(void)
2386 {
2387         struct sys_device * dev;
2388         int i, size, error = 0;
2389
2390         error = sysdev_class_register(&ioapic_sysdev_class);
2391         if (error)
2392                 return error;
2393
2394         for (i = 0; i < nr_ioapics; i++ ) {
2395                 size = sizeof(struct sys_device) + nr_ioapic_registers[i] 
2396                         * sizeof(struct IO_APIC_route_entry);
2397                 mp_ioapic_data[i] = kmalloc(size, GFP_KERNEL);
2398                 if (!mp_ioapic_data[i]) {
2399                         printk(KERN_ERR "Can't suspend/resume IOAPIC %d\n", i);
2400                         continue;
2401                 }
2402                 memset(mp_ioapic_data[i], 0, size);
2403                 dev = &mp_ioapic_data[i]->dev;
2404                 dev->id = i; 
2405                 dev->cls = &ioapic_sysdev_class;
2406                 error = sysdev_register(dev);
2407                 if (error) {
2408                         kfree(mp_ioapic_data[i]);
2409                         mp_ioapic_data[i] = NULL;
2410                         printk(KERN_ERR "Can't suspend/resume IOAPIC %d\n", i);
2411                         continue;
2412                 }
2413         }
2414
2415         return 0;
2416 }
2417
2418 device_initcall(ioapic_init_sysfs);
2419
2420 /* --------------------------------------------------------------------------
2421                           ACPI-based IOAPIC Configuration
2422    -------------------------------------------------------------------------- */
2423
2424 #ifdef CONFIG_ACPI_BOOT
2425
2426 int __init io_apic_get_unique_id (int ioapic, int apic_id)
2427 {
2428         union IO_APIC_reg_00 reg_00;
2429         static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
2430         physid_mask_t tmp;
2431         unsigned long flags;
2432         int i = 0;
2433
2434         /*
2435          * The P4 platform supports up to 256 APIC IDs on two separate APIC 
2436          * buses (one for LAPICs, one for IOAPICs), where predecessors only 
2437          * supports up to 16 on one shared APIC bus.
2438          * 
2439          * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
2440          *      advantage of new APIC bus architecture.
2441          */
2442
2443         if (physids_empty(apic_id_map))
2444                 apic_id_map = ioapic_phys_id_map(phys_cpu_present_map);
2445
2446         spin_lock_irqsave(&ioapic_lock, flags);
2447         reg_00.raw = io_apic_read(ioapic, 0);
2448         spin_unlock_irqrestore(&ioapic_lock, flags);
2449
2450         if (apic_id >= get_physical_broadcast()) {
2451                 printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
2452                         "%d\n", ioapic, apic_id, reg_00.bits.ID);
2453                 apic_id = reg_00.bits.ID;
2454         }
2455
2456         /*
2457          * Every APIC in a system must have a unique ID or we get lots of nice 
2458          * 'stuck on smp_invalidate_needed IPI wait' messages.
2459          */
2460         if (check_apicid_used(apic_id_map, apic_id)) {
2461
2462                 for (i = 0; i < get_physical_broadcast(); i++) {
2463                         if (!check_apicid_used(apic_id_map, i))
2464                                 break;
2465                 }
2466
2467                 if (i == get_physical_broadcast())
2468                         panic("Max apic_id exceeded!\n");
2469
2470                 printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
2471                         "trying %d\n", ioapic, apic_id, i);
2472
2473                 apic_id = i;
2474         } 
2475
2476         tmp = apicid_to_cpu_present(apic_id);
2477         physids_or(apic_id_map, apic_id_map, tmp);
2478
2479         if (reg_00.bits.ID != apic_id) {
2480                 reg_00.bits.ID = apic_id;
2481
2482                 spin_lock_irqsave(&ioapic_lock, flags);
2483                 io_apic_write(ioapic, 0, reg_00.raw);
2484                 reg_00.raw = io_apic_read(ioapic, 0);
2485                 spin_unlock_irqrestore(&ioapic_lock, flags);
2486
2487                 /* Sanity check */
2488                 if (reg_00.bits.ID != apic_id)
2489                         panic("IOAPIC[%d]: Unable change apic_id!\n", ioapic);
2490         }
2491
2492         apic_printk(APIC_VERBOSE, KERN_INFO
2493                         "IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
2494
2495         return apic_id;
2496 }
2497
2498
2499 int __init io_apic_get_version (int ioapic)
2500 {
2501         union IO_APIC_reg_01    reg_01;
2502         unsigned long flags;
2503
2504         spin_lock_irqsave(&ioapic_lock, flags);
2505         reg_01.raw = io_apic_read(ioapic, 1);
2506         spin_unlock_irqrestore(&ioapic_lock, flags);
2507
2508         return reg_01.bits.version;
2509 }
2510
2511
2512 int __init io_apic_get_redir_entries (int ioapic)
2513 {
2514         union IO_APIC_reg_01    reg_01;
2515         unsigned long flags;
2516
2517         spin_lock_irqsave(&ioapic_lock, flags);
2518         reg_01.raw = io_apic_read(ioapic, 1);
2519         spin_unlock_irqrestore(&ioapic_lock, flags);
2520
2521         return reg_01.bits.entries;
2522 }
2523
2524
2525 int io_apic_set_pci_routing (int ioapic, int pin, int irq, int edge_level, int active_high_low)
2526 {
2527         struct IO_APIC_route_entry entry;
2528         unsigned long flags;
2529
2530         if (!IO_APIC_IRQ(irq)) {
2531                 printk(KERN_ERR "IOAPIC[%d]: Invalid reference to IRQ 0\n",
2532                         ioapic);
2533                 return -EINVAL;
2534         }
2535
2536         /*
2537          * Generate a PCI IRQ routing entry and program the IOAPIC accordingly.
2538          * Note that we mask (disable) IRQs now -- these get enabled when the
2539          * corresponding device driver registers for this IRQ.
2540          */
2541
2542         memset(&entry,0,sizeof(entry));
2543
2544         entry.delivery_mode = INT_DELIVERY_MODE;
2545         entry.dest_mode = INT_DEST_MODE;
2546         entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS);
2547         entry.trigger = edge_level;
2548         entry.polarity = active_high_low;
2549         entry.mask  = 1;
2550
2551         /*
2552          * IRQs < 16 are already in the irq_2_pin[] map
2553          */
2554         if (irq >= 16)
2555                 add_pin_to_irq(irq, ioapic, pin);
2556
2557         entry.vector = assign_irq_vector(irq);
2558
2559         apic_printk(APIC_DEBUG, KERN_DEBUG "IOAPIC[%d]: Set PCI routing entry "
2560                 "(%d-%d -> 0x%x -> IRQ %d Mode:%i Active:%i)\n", ioapic,
2561                 mp_ioapics[ioapic].mpc_apicid, pin, entry.vector, irq,
2562                 edge_level, active_high_low);
2563
2564         ioapic_register_intr(irq, entry.vector, edge_level);
2565
2566         if (!ioapic && (irq < 16))
2567                 disable_8259A_irq(irq);
2568
2569         spin_lock_irqsave(&ioapic_lock, flags);
2570         io_apic_write(ioapic, 0x11+2*pin, *(((int *)&entry)+1));
2571         io_apic_write(ioapic, 0x10+2*pin, *(((int *)&entry)+0));
2572         spin_unlock_irqrestore(&ioapic_lock, flags);
2573
2574         return 0;
2575 }
2576
2577 #endif /*CONFIG_ACPI_BOOT*/