Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
[linux-2.6] / arch / powerpc / platforms / pseries / xics.c
1 /*
2  * arch/powerpc/platforms/pseries/xics.c
3  *
4  * Copyright 2000 IBM Corporation.
5  *
6  *  This program is free software; you can redistribute it and/or
7  *  modify it under the terms of the GNU General Public License
8  *  as published by the Free Software Foundation; either version
9  *  2 of the License, or (at your option) any later version.
10  */
11
12 #undef DEBUG
13
14 #include <linux/types.h>
15 #include <linux/threads.h>
16 #include <linux/kernel.h>
17 #include <linux/irq.h>
18 #include <linux/smp.h>
19 #include <linux/interrupt.h>
20 #include <linux/signal.h>
21 #include <linux/init.h>
22 #include <linux/gfp.h>
23 #include <linux/radix-tree.h>
24 #include <linux/cpu.h>
25
26 #include <asm/firmware.h>
27 #include <asm/prom.h>
28 #include <asm/io.h>
29 #include <asm/pgtable.h>
30 #include <asm/smp.h>
31 #include <asm/rtas.h>
32 #include <asm/hvcall.h>
33 #include <asm/machdep.h>
34 #include <asm/i8259.h>
35
36 #include "xics.h"
37 #include "plpar_wrappers.h"
38
39 #define XICS_IPI                2
40 #define XICS_IRQ_SPURIOUS       0
41
42 /* Want a priority other than 0.  Various HW issues require this. */
43 #define DEFAULT_PRIORITY        5
44
45 /*
46  * Mark IPIs as higher priority so we can take them inside interrupts that
47  * arent marked IRQF_DISABLED
48  */
49 #define IPI_PRIORITY            4
50
51 struct xics_ipl {
52         union {
53                 u32 word;
54                 u8 bytes[4];
55         } xirr_poll;
56         union {
57                 u32 word;
58                 u8 bytes[4];
59         } xirr;
60         u32 dummy;
61         union {
62                 u32 word;
63                 u8 bytes[4];
64         } qirr;
65 };
66
67 static struct xics_ipl __iomem *xics_per_cpu[NR_CPUS];
68
69 static unsigned int default_server = 0xFF;
70 static unsigned int default_distrib_server = 0;
71 static unsigned int interrupt_server_size = 8;
72
73 static struct irq_host *xics_host;
74
75 /*
76  * XICS only has a single IPI, so encode the messages per CPU
77  */
78 struct xics_ipi_struct xics_ipi_message[NR_CPUS] __cacheline_aligned;
79
80 /* RTAS service tokens */
81 static int ibm_get_xive;
82 static int ibm_set_xive;
83 static int ibm_int_on;
84 static int ibm_int_off;
85
86
87 /* Direct HW low level accessors */
88
89
90 static inline unsigned int direct_xirr_info_get(int n_cpu)
91 {
92         return in_be32(&xics_per_cpu[n_cpu]->xirr.word);
93 }
94
95 static inline void direct_xirr_info_set(int n_cpu, int value)
96 {
97         out_be32(&xics_per_cpu[n_cpu]->xirr.word, value);
98 }
99
100 static inline void direct_cppr_info(int n_cpu, u8 value)
101 {
102         out_8(&xics_per_cpu[n_cpu]->xirr.bytes[0], value);
103 }
104
105 static inline void direct_qirr_info(int n_cpu, u8 value)
106 {
107         out_8(&xics_per_cpu[n_cpu]->qirr.bytes[0], value);
108 }
109
110
111 /* LPAR low level accessors */
112
113
114 static inline unsigned int lpar_xirr_info_get(int n_cpu)
115 {
116         unsigned long lpar_rc;
117         unsigned long return_value;
118
119         lpar_rc = plpar_xirr(&return_value);
120         if (lpar_rc != H_SUCCESS)
121                 panic(" bad return code xirr - rc = %lx \n", lpar_rc);
122         return (unsigned int)return_value;
123 }
124
125 static inline void lpar_xirr_info_set(int n_cpu, int value)
126 {
127         unsigned long lpar_rc;
128         unsigned long val64 = value & 0xffffffff;
129
130         lpar_rc = plpar_eoi(val64);
131         if (lpar_rc != H_SUCCESS)
132                 panic("bad return code EOI - rc = %ld, value=%lx\n", lpar_rc,
133                       val64);
134 }
135
136 static inline void lpar_cppr_info(int n_cpu, u8 value)
137 {
138         unsigned long lpar_rc;
139
140         lpar_rc = plpar_cppr(value);
141         if (lpar_rc != H_SUCCESS)
142                 panic("bad return code cppr - rc = %lx\n", lpar_rc);
143 }
144
145 static inline void lpar_qirr_info(int n_cpu , u8 value)
146 {
147         unsigned long lpar_rc;
148
149         lpar_rc = plpar_ipi(get_hard_smp_processor_id(n_cpu), value);
150         if (lpar_rc != H_SUCCESS)
151                 panic("bad return code qirr - rc = %lx\n", lpar_rc);
152 }
153
154
155 /* High level handlers and init code */
156
157
158 #ifdef CONFIG_SMP
159 static int get_irq_server(unsigned int virq)
160 {
161         unsigned int server;
162         /* For the moment only implement delivery to all cpus or one cpu */
163         cpumask_t cpumask = irq_desc[virq].affinity;
164         cpumask_t tmp = CPU_MASK_NONE;
165
166         if (!distribute_irqs)
167                 return default_server;
168
169         if (cpus_equal(cpumask, CPU_MASK_ALL)) {
170                 server = default_distrib_server;
171         } else {
172                 cpus_and(tmp, cpu_online_map, cpumask);
173
174                 if (cpus_empty(tmp))
175                         server = default_distrib_server;
176                 else
177                         server = get_hard_smp_processor_id(first_cpu(tmp));
178         }
179
180         return server;
181
182 }
183 #else
184 static int get_irq_server(unsigned int virq)
185 {
186         return default_server;
187 }
188 #endif
189
190
191 static void xics_unmask_irq(unsigned int virq)
192 {
193         unsigned int irq;
194         int call_status;
195         unsigned int server;
196
197         pr_debug("xics: unmask virq %d\n", virq);
198
199         irq = (unsigned int)irq_map[virq].hwirq;
200         pr_debug(" -> map to hwirq 0x%x\n", irq);
201         if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
202                 return;
203
204         server = get_irq_server(virq);
205
206         call_status = rtas_call(ibm_set_xive, 3, 1, NULL, irq, server,
207                                 DEFAULT_PRIORITY);
208         if (call_status != 0) {
209                 printk(KERN_ERR "xics_enable_irq: irq=%u: ibm_set_xive "
210                        "returned %d\n", irq, call_status);
211                 printk("set_xive %x, server %x\n", ibm_set_xive, server);
212                 return;
213         }
214
215         /* Now unmask the interrupt (often a no-op) */
216         call_status = rtas_call(ibm_int_on, 1, 1, NULL, irq);
217         if (call_status != 0) {
218                 printk(KERN_ERR "xics_enable_irq: irq=%u: ibm_int_on "
219                        "returned %d\n", irq, call_status);
220                 return;
221         }
222 }
223
224 static void xics_mask_real_irq(unsigned int irq)
225 {
226         int call_status;
227
228         if (irq == XICS_IPI)
229                 return;
230
231         call_status = rtas_call(ibm_int_off, 1, 1, NULL, irq);
232         if (call_status != 0) {
233                 printk(KERN_ERR "xics_disable_real_irq: irq=%u: "
234                        "ibm_int_off returned %d\n", irq, call_status);
235                 return;
236         }
237
238         /* Have to set XIVE to 0xff to be able to remove a slot */
239         call_status = rtas_call(ibm_set_xive, 3, 1, NULL, irq,
240                                 default_server, 0xff);
241         if (call_status != 0) {
242                 printk(KERN_ERR "xics_disable_irq: irq=%u: ibm_set_xive(0xff)"
243                        " returned %d\n", irq, call_status);
244                 return;
245         }
246 }
247
248 static void xics_mask_irq(unsigned int virq)
249 {
250         unsigned int irq;
251
252         pr_debug("xics: mask virq %d\n", virq);
253
254         irq = (unsigned int)irq_map[virq].hwirq;
255         if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
256                 return;
257         xics_mask_real_irq(irq);
258 }
259
260 static unsigned int xics_startup(unsigned int virq)
261 {
262         unsigned int irq;
263
264         /* force a reverse mapping of the interrupt so it gets in the cache */
265         irq = (unsigned int)irq_map[virq].hwirq;
266         irq_radix_revmap(xics_host, irq);
267
268         /* unmask it */
269         xics_unmask_irq(virq);
270         return 0;
271 }
272
273 static void xics_eoi_direct(unsigned int virq)
274 {
275         int cpu = smp_processor_id();
276         unsigned int irq = (unsigned int)irq_map[virq].hwirq;
277
278         iosync();
279         direct_xirr_info_set(cpu, (0xff << 24) | irq);
280 }
281
282
283 static void xics_eoi_lpar(unsigned int virq)
284 {
285         int cpu = smp_processor_id();
286         unsigned int irq = (unsigned int)irq_map[virq].hwirq;
287
288         iosync();
289         lpar_xirr_info_set(cpu, (0xff << 24) | irq);
290 }
291
292 static inline unsigned int xics_remap_irq(unsigned int vec)
293 {
294         unsigned int irq;
295
296         vec &= 0x00ffffff;
297
298         if (vec == XICS_IRQ_SPURIOUS)
299                 return NO_IRQ;
300         irq = irq_radix_revmap(xics_host, vec);
301         if (likely(irq != NO_IRQ))
302                 return irq;
303
304         printk(KERN_ERR "Interrupt %u (real) is invalid,"
305                " disabling it.\n", vec);
306         xics_mask_real_irq(vec);
307         return NO_IRQ;
308 }
309
310 static unsigned int xics_get_irq_direct(void)
311 {
312         unsigned int cpu = smp_processor_id();
313
314         return xics_remap_irq(direct_xirr_info_get(cpu));
315 }
316
317 static unsigned int xics_get_irq_lpar(void)
318 {
319         unsigned int cpu = smp_processor_id();
320
321         return xics_remap_irq(lpar_xirr_info_get(cpu));
322 }
323
324 #ifdef CONFIG_SMP
325
326 static irqreturn_t xics_ipi_dispatch(int cpu)
327 {
328         WARN_ON(cpu_is_offline(cpu));
329
330         while (xics_ipi_message[cpu].value) {
331                 if (test_and_clear_bit(PPC_MSG_CALL_FUNCTION,
332                                        &xics_ipi_message[cpu].value)) {
333                         mb();
334                         smp_message_recv(PPC_MSG_CALL_FUNCTION);
335                 }
336                 if (test_and_clear_bit(PPC_MSG_RESCHEDULE,
337                                        &xics_ipi_message[cpu].value)) {
338                         mb();
339                         smp_message_recv(PPC_MSG_RESCHEDULE);
340                 }
341 #if 0
342                 if (test_and_clear_bit(PPC_MSG_MIGRATE_TASK,
343                                        &xics_ipi_message[cpu].value)) {
344                         mb();
345                         smp_message_recv(PPC_MSG_MIGRATE_TASK);
346                 }
347 #endif
348 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
349                 if (test_and_clear_bit(PPC_MSG_DEBUGGER_BREAK,
350                                        &xics_ipi_message[cpu].value)) {
351                         mb();
352                         smp_message_recv(PPC_MSG_DEBUGGER_BREAK);
353                 }
354 #endif
355         }
356         return IRQ_HANDLED;
357 }
358
359 static irqreturn_t xics_ipi_action_direct(int irq, void *dev_id)
360 {
361         int cpu = smp_processor_id();
362
363         direct_qirr_info(cpu, 0xff);
364
365         return xics_ipi_dispatch(cpu);
366 }
367
368 static irqreturn_t xics_ipi_action_lpar(int irq, void *dev_id)
369 {
370         int cpu = smp_processor_id();
371
372         lpar_qirr_info(cpu, 0xff);
373
374         return xics_ipi_dispatch(cpu);
375 }
376
377 void xics_cause_IPI(int cpu)
378 {
379         if (firmware_has_feature(FW_FEATURE_LPAR))
380                 lpar_qirr_info(cpu, IPI_PRIORITY);
381         else
382                 direct_qirr_info(cpu, IPI_PRIORITY);
383 }
384
385 #endif /* CONFIG_SMP */
386
387 static void xics_set_cpu_priority(int cpu, unsigned char cppr)
388 {
389         if (firmware_has_feature(FW_FEATURE_LPAR))
390                 lpar_cppr_info(cpu, cppr);
391         else
392                 direct_cppr_info(cpu, cppr);
393         iosync();
394 }
395
396 static void xics_set_affinity(unsigned int virq, cpumask_t cpumask)
397 {
398         unsigned int irq;
399         int status;
400         int xics_status[2];
401         unsigned long newmask;
402         cpumask_t tmp = CPU_MASK_NONE;
403
404         irq = (unsigned int)irq_map[virq].hwirq;
405         if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
406                 return;
407
408         status = rtas_call(ibm_get_xive, 1, 3, xics_status, irq);
409
410         if (status) {
411                 printk(KERN_ERR "xics_set_affinity: irq=%u ibm,get-xive "
412                        "returns %d\n", irq, status);
413                 return;
414         }
415
416         /* For the moment only implement delivery to all cpus or one cpu */
417         if (cpus_equal(cpumask, CPU_MASK_ALL)) {
418                 newmask = default_distrib_server;
419         } else {
420                 cpus_and(tmp, cpu_online_map, cpumask);
421                 if (cpus_empty(tmp))
422                         return;
423                 newmask = get_hard_smp_processor_id(first_cpu(tmp));
424         }
425
426         status = rtas_call(ibm_set_xive, 3, 1, NULL,
427                                 irq, newmask, xics_status[1]);
428
429         if (status) {
430                 printk(KERN_ERR "xics_set_affinity: irq=%u ibm,set-xive "
431                        "returns %d\n", irq, status);
432                 return;
433         }
434 }
435
436 void xics_setup_cpu(void)
437 {
438         int cpu = smp_processor_id();
439
440         xics_set_cpu_priority(cpu, 0xff);
441
442         /*
443          * Put the calling processor into the GIQ.  This is really only
444          * necessary from a secondary thread as the OF start-cpu interface
445          * performs this function for us on primary threads.
446          *
447          * XXX: undo of teardown on kexec needs this too, as may hotplug
448          */
449         rtas_set_indicator_fast(GLOBAL_INTERRUPT_QUEUE,
450                 (1UL << interrupt_server_size) - 1 - default_distrib_server, 1);
451 }
452
453
454 static struct irq_chip xics_pic_direct = {
455         .typename = " XICS     ",
456         .startup = xics_startup,
457         .mask = xics_mask_irq,
458         .unmask = xics_unmask_irq,
459         .eoi = xics_eoi_direct,
460         .set_affinity = xics_set_affinity
461 };
462
463
464 static struct irq_chip xics_pic_lpar = {
465         .typename = " XICS     ",
466         .startup = xics_startup,
467         .mask = xics_mask_irq,
468         .unmask = xics_unmask_irq,
469         .eoi = xics_eoi_lpar,
470         .set_affinity = xics_set_affinity
471 };
472
473
474 static int xics_host_match(struct irq_host *h, struct device_node *node)
475 {
476         /* IBM machines have interrupt parents of various funky types for things
477          * like vdevices, events, etc... The trick we use here is to match
478          * everything here except the legacy 8259 which is compatible "chrp,iic"
479          */
480         return !of_device_is_compatible(node, "chrp,iic");
481 }
482
483 static int xics_host_map_direct(struct irq_host *h, unsigned int virq,
484                                 irq_hw_number_t hw)
485 {
486         pr_debug("xics: map_direct virq %d, hwirq 0x%lx\n", virq, hw);
487
488         get_irq_desc(virq)->status |= IRQ_LEVEL;
489         set_irq_chip_and_handler(virq, &xics_pic_direct, handle_fasteoi_irq);
490         return 0;
491 }
492
493 static int xics_host_map_lpar(struct irq_host *h, unsigned int virq,
494                               irq_hw_number_t hw)
495 {
496         pr_debug("xics: map_direct virq %d, hwirq 0x%lx\n", virq, hw);
497
498         get_irq_desc(virq)->status |= IRQ_LEVEL;
499         set_irq_chip_and_handler(virq, &xics_pic_lpar, handle_fasteoi_irq);
500         return 0;
501 }
502
503 static int xics_host_xlate(struct irq_host *h, struct device_node *ct,
504                            u32 *intspec, unsigned int intsize,
505                            irq_hw_number_t *out_hwirq, unsigned int *out_flags)
506
507 {
508         /* Current xics implementation translates everything
509          * to level. It is not technically right for MSIs but this
510          * is irrelevant at this point. We might get smarter in the future
511          */
512         *out_hwirq = intspec[0];
513         *out_flags = IRQ_TYPE_LEVEL_LOW;
514
515         return 0;
516 }
517
518 static struct irq_host_ops xics_host_direct_ops = {
519         .match = xics_host_match,
520         .map = xics_host_map_direct,
521         .xlate = xics_host_xlate,
522 };
523
524 static struct irq_host_ops xics_host_lpar_ops = {
525         .match = xics_host_match,
526         .map = xics_host_map_lpar,
527         .xlate = xics_host_xlate,
528 };
529
530 static void __init xics_init_host(void)
531 {
532         struct irq_host_ops *ops;
533
534         if (firmware_has_feature(FW_FEATURE_LPAR))
535                 ops = &xics_host_lpar_ops;
536         else
537                 ops = &xics_host_direct_ops;
538         xics_host = irq_alloc_host(IRQ_HOST_MAP_TREE, 0, ops,
539                                    XICS_IRQ_SPURIOUS);
540         BUG_ON(xics_host == NULL);
541         irq_set_default_host(xics_host);
542 }
543
544 static void __init xics_map_one_cpu(int hw_id, unsigned long addr,
545                                      unsigned long size)
546 {
547 #ifdef CONFIG_SMP
548         int i;
549
550         /* This may look gross but it's good enough for now, we don't quite
551          * have a hard -> linux processor id matching.
552          */
553         for_each_possible_cpu(i) {
554                 if (!cpu_present(i))
555                         continue;
556                 if (hw_id == get_hard_smp_processor_id(i)) {
557                         xics_per_cpu[i] = ioremap(addr, size);
558                         return;
559                 }
560         }
561 #else
562         if (hw_id != 0)
563                 return;
564         xics_per_cpu[0] = ioremap(addr, size);
565 #endif /* CONFIG_SMP */
566 }
567
568 static void __init xics_init_one_node(struct device_node *np,
569                                       unsigned int *indx)
570 {
571         unsigned int ilen;
572         const u32 *ireg;
573
574         /* This code does the theorically broken assumption that the interrupt
575          * server numbers are the same as the hard CPU numbers.
576          * This happens to be the case so far but we are playing with fire...
577          * should be fixed one of these days. -BenH.
578          */
579         ireg = of_get_property(np, "ibm,interrupt-server-ranges", NULL);
580
581         /* Do that ever happen ? we'll know soon enough... but even good'old
582          * f80 does have that property ..
583          */
584         WARN_ON(ireg == NULL);
585         if (ireg) {
586                 /*
587                  * set node starting index for this node
588                  */
589                 *indx = *ireg;
590         }
591         ireg = of_get_property(np, "reg", &ilen);
592         if (!ireg)
593                 panic("xics_init_IRQ: can't find interrupt reg property");
594
595         while (ilen >= (4 * sizeof(u32))) {
596                 unsigned long addr, size;
597
598                 /* XXX Use proper OF parsing code here !!! */
599                 addr = (unsigned long)*ireg++ << 32;
600                 ilen -= sizeof(u32);
601                 addr |= *ireg++;
602                 ilen -= sizeof(u32);
603                 size = (unsigned long)*ireg++ << 32;
604                 ilen -= sizeof(u32);
605                 size |= *ireg++;
606                 ilen -= sizeof(u32);
607                 xics_map_one_cpu(*indx, addr, size);
608                 (*indx)++;
609         }
610 }
611
612
613 static void __init xics_setup_8259_cascade(void)
614 {
615         struct device_node *np, *old, *found = NULL;
616         int cascade, naddr;
617         const u32 *addrp;
618         unsigned long intack = 0;
619
620         for_each_node_by_type(np, "interrupt-controller")
621                 if (of_device_is_compatible(np, "chrp,iic")) {
622                         found = np;
623                         break;
624                 }
625         if (found == NULL) {
626                 printk(KERN_DEBUG "xics: no ISA interrupt controller\n");
627                 return;
628         }
629         cascade = irq_of_parse_and_map(found, 0);
630         if (cascade == NO_IRQ) {
631                 printk(KERN_ERR "xics: failed to map cascade interrupt");
632                 return;
633         }
634         pr_debug("xics: cascade mapped to irq %d\n", cascade);
635
636         for (old = of_node_get(found); old != NULL ; old = np) {
637                 np = of_get_parent(old);
638                 of_node_put(old);
639                 if (np == NULL)
640                         break;
641                 if (strcmp(np->name, "pci") != 0)
642                         continue;
643                 addrp = of_get_property(np, "8259-interrupt-acknowledge", NULL);
644                 if (addrp == NULL)
645                         continue;
646                 naddr = of_n_addr_cells(np);
647                 intack = addrp[naddr-1];
648                 if (naddr > 1)
649                         intack |= ((unsigned long)addrp[naddr-2]) << 32;
650         }
651         if (intack)
652                 printk(KERN_DEBUG "xics: PCI 8259 intack at 0x%016lx\n", intack);
653         i8259_init(found, intack);
654         of_node_put(found);
655         set_irq_chained_handler(cascade, pseries_8259_cascade);
656 }
657
658 static struct device_node *cpuid_to_of_node(int cpu)
659 {
660         struct device_node *np;
661         u32 hcpuid = get_hard_smp_processor_id(cpu);
662
663         for_each_node_by_type(np, "cpu") {
664                 int i, len;
665                 const u32 *intserv;
666
667                 intserv = of_get_property(np, "ibm,ppc-interrupt-server#s",
668                                         &len);
669
670                 if (!intserv)
671                         intserv = of_get_property(np, "reg", &len);
672
673                 i = len / sizeof(u32);
674
675                 while (i--)
676                         if (intserv[i] == hcpuid)
677                                 return np;
678         }
679
680         return NULL;
681 }
682
683 void __init xics_init_IRQ(void)
684 {
685         int i, j;
686         struct device_node *np;
687         u32 ilen, indx = 0;
688         const u32 *ireg, *isize;
689         int found = 0;
690         u32 hcpuid;
691
692         ppc64_boot_msg(0x20, "XICS Init");
693
694         ibm_get_xive = rtas_token("ibm,get-xive");
695         ibm_set_xive = rtas_token("ibm,set-xive");
696         ibm_int_on  = rtas_token("ibm,int-on");
697         ibm_int_off = rtas_token("ibm,int-off");
698
699         for_each_node_by_type(np, "PowerPC-External-Interrupt-Presentation") {
700                 found = 1;
701                 if (firmware_has_feature(FW_FEATURE_LPAR))
702                         break;
703                 xics_init_one_node(np, &indx);
704         }
705         if (found == 0)
706                 return;
707
708         xics_init_host();
709
710         /* Find the server numbers for the boot cpu. */
711         np = cpuid_to_of_node(boot_cpuid);
712         BUG_ON(!np);
713         ireg = of_get_property(np, "ibm,ppc-interrupt-gserver#s", &ilen);
714         if (!ireg)
715                 goto skip_gserver_check;
716         i = ilen / sizeof(int);
717         hcpuid = get_hard_smp_processor_id(boot_cpuid);
718
719         /* Global interrupt distribution server is specified in the last
720          * entry of "ibm,ppc-interrupt-gserver#s" property. Get the last
721          * entry fom this property for current boot cpu id and use it as
722          * default distribution server
723          */
724         for (j = 0; j < i; j += 2) {
725                 if (ireg[j] == hcpuid) {
726                         default_server = hcpuid;
727                         default_distrib_server = ireg[j+1];
728
729                         isize = of_get_property(np,
730                                         "ibm,interrupt-server#-size", NULL);
731                         if (isize)
732                                 interrupt_server_size = *isize;
733                 }
734         }
735 skip_gserver_check:
736         of_node_put(np);
737
738         if (firmware_has_feature(FW_FEATURE_LPAR))
739                 ppc_md.get_irq = xics_get_irq_lpar;
740         else
741                 ppc_md.get_irq = xics_get_irq_direct;
742
743         xics_setup_cpu();
744
745         xics_setup_8259_cascade();
746
747         ppc64_boot_msg(0x21, "XICS Done");
748 }
749
750
751 #ifdef CONFIG_SMP
752 void xics_request_IPIs(void)
753 {
754         unsigned int ipi;
755         int rc;
756
757         ipi = irq_create_mapping(xics_host, XICS_IPI);
758         BUG_ON(ipi == NO_IRQ);
759
760         /*
761          * IPIs are marked IRQF_DISABLED as they must run with irqs
762          * disabled
763          */
764         set_irq_handler(ipi, handle_percpu_irq);
765         if (firmware_has_feature(FW_FEATURE_LPAR))
766                 rc = request_irq(ipi, xics_ipi_action_lpar, IRQF_DISABLED,
767                                 "IPI", NULL);
768         else
769                 rc = request_irq(ipi, xics_ipi_action_direct, IRQF_DISABLED,
770                                 "IPI", NULL);
771         BUG_ON(rc);
772 }
773 #endif /* CONFIG_SMP */
774
775 void xics_teardown_cpu(int secondary)
776 {
777         int cpu = smp_processor_id();
778         unsigned int ipi;
779         struct irq_desc *desc;
780
781         xics_set_cpu_priority(cpu, 0);
782
783         /*
784          * Clear IPI
785          */
786         if (firmware_has_feature(FW_FEATURE_LPAR))
787                 lpar_qirr_info(cpu, 0xff);
788         else
789                 direct_qirr_info(cpu, 0xff);
790
791         /*
792          * we need to EOI the IPI if we got here from kexec down IPI
793          *
794          * probably need to check all the other interrupts too
795          * should we be flagging idle loop instead?
796          * or creating some task to be scheduled?
797          */
798
799         ipi = irq_find_mapping(xics_host, XICS_IPI);
800         if (ipi == XICS_IRQ_SPURIOUS)
801                 return;
802         desc = get_irq_desc(ipi);
803         if (desc->chip && desc->chip->eoi)
804                 desc->chip->eoi(ipi);
805
806         /*
807          * Some machines need to have at least one cpu in the GIQ,
808          * so leave the master cpu in the group.
809          */
810         if (secondary)
811                 rtas_set_indicator_fast(GLOBAL_INTERRUPT_QUEUE,
812                                    (1UL << interrupt_server_size) - 1 -
813                                    default_distrib_server, 0);
814 }
815
816 #ifdef CONFIG_HOTPLUG_CPU
817
818 /* Interrupts are disabled. */
819 void xics_migrate_irqs_away(void)
820 {
821         int status;
822         unsigned int irq, virq, cpu = smp_processor_id();
823
824         /* Reject any interrupt that was queued to us... */
825         xics_set_cpu_priority(cpu, 0);
826
827         /* remove ourselves from the global interrupt queue */
828         status = rtas_set_indicator_fast(GLOBAL_INTERRUPT_QUEUE,
829                 (1UL << interrupt_server_size) - 1 - default_distrib_server, 0);
830         WARN_ON(status < 0);
831
832         /* Allow IPIs again... */
833         xics_set_cpu_priority(cpu, DEFAULT_PRIORITY);
834
835         for_each_irq(virq) {
836                 struct irq_desc *desc;
837                 int xics_status[2];
838                 unsigned long flags;
839
840                 /* We cant set affinity on ISA interrupts */
841                 if (virq < NUM_ISA_INTERRUPTS)
842                         continue;
843                 if (irq_map[virq].host != xics_host)
844                         continue;
845                 irq = (unsigned int)irq_map[virq].hwirq;
846                 /* We need to get IPIs still. */
847                 if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
848                         continue;
849                 desc = get_irq_desc(virq);
850
851                 /* We only need to migrate enabled IRQS */
852                 if (desc == NULL || desc->chip == NULL
853                     || desc->action == NULL
854                     || desc->chip->set_affinity == NULL)
855                         continue;
856
857                 spin_lock_irqsave(&desc->lock, flags);
858
859                 status = rtas_call(ibm_get_xive, 1, 3, xics_status, irq);
860                 if (status) {
861                         printk(KERN_ERR "migrate_irqs_away: irq=%u "
862                                         "ibm,get-xive returns %d\n",
863                                         virq, status);
864                         goto unlock;
865                 }
866
867                 /*
868                  * We only support delivery to all cpus or to one cpu.
869                  * The irq has to be migrated only in the single cpu
870                  * case.
871                  */
872                 if (xics_status[0] != get_hard_smp_processor_id(cpu))
873                         goto unlock;
874
875                 printk(KERN_WARNING "IRQ %u affinity broken off cpu %u\n",
876                        virq, cpu);
877
878                 /* Reset affinity to all cpus */
879                 desc->chip->set_affinity(virq, CPU_MASK_ALL);
880                 irq_desc[irq].affinity = CPU_MASK_ALL;
881 unlock:
882                 spin_unlock_irqrestore(&desc->lock, flags);
883         }
884 }
885 #endif