Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / arch / ia64 / sn / kernel / irq.c
1 /*
2  * Platform dependent support for SGI SN
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (c) 2000-2006 Silicon Graphics, Inc.  All Rights Reserved.
9  */
10
11 #include <linux/irq.h>
12 #include <linux/spinlock.h>
13 #include <linux/init.h>
14 #include <asm/sn/addrs.h>
15 #include <asm/sn/arch.h>
16 #include <asm/sn/intr.h>
17 #include <asm/sn/pcibr_provider.h>
18 #include <asm/sn/pcibus_provider_defs.h>
19 #include <asm/sn/pcidev.h>
20 #include <asm/sn/shub_mmr.h>
21 #include <asm/sn/sn_sal.h>
22
23 static void force_interrupt(int irq);
24 static void register_intr_pda(struct sn_irq_info *sn_irq_info);
25 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info);
26
27 int sn_force_interrupt_flag = 1;
28 extern int sn_ioif_inited;
29 struct list_head **sn_irq_lh;
30 static DEFINE_SPINLOCK(sn_irq_info_lock); /* non-IRQ lock */
31
32 u64 sn_intr_alloc(nasid_t local_nasid, int local_widget,
33                                      struct sn_irq_info *sn_irq_info,
34                                      int req_irq, nasid_t req_nasid,
35                                      int req_slice)
36 {
37         struct ia64_sal_retval ret_stuff;
38         ret_stuff.status = 0;
39         ret_stuff.v0 = 0;
40
41         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
42                         (u64) SAL_INTR_ALLOC, (u64) local_nasid,
43                         (u64) local_widget, __pa(sn_irq_info), (u64) req_irq,
44                         (u64) req_nasid, (u64) req_slice);
45
46         return ret_stuff.status;
47 }
48
49 void sn_intr_free(nasid_t local_nasid, int local_widget,
50                                 struct sn_irq_info *sn_irq_info)
51 {
52         struct ia64_sal_retval ret_stuff;
53         ret_stuff.status = 0;
54         ret_stuff.v0 = 0;
55
56         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
57                         (u64) SAL_INTR_FREE, (u64) local_nasid,
58                         (u64) local_widget, (u64) sn_irq_info->irq_irq,
59                         (u64) sn_irq_info->irq_cookie, 0, 0);
60 }
61
62 static unsigned int sn_startup_irq(unsigned int irq)
63 {
64         return 0;
65 }
66
67 static void sn_shutdown_irq(unsigned int irq)
68 {
69 }
70
71 static void sn_disable_irq(unsigned int irq)
72 {
73 }
74
75 static void sn_enable_irq(unsigned int irq)
76 {
77 }
78
79 static void sn_ack_irq(unsigned int irq)
80 {
81         u64 event_occurred, mask;
82
83         irq = irq & 0xff;
84         event_occurred = HUB_L((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED));
85         mask = event_occurred & SH_ALL_INT_MASK;
86         HUB_S((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS), mask);
87         __set_bit(irq, (volatile void *)pda->sn_in_service_ivecs);
88
89         move_native_irq(irq);
90 }
91
92 static void sn_end_irq(unsigned int irq)
93 {
94         int ivec;
95         u64 event_occurred;
96
97         ivec = irq & 0xff;
98         if (ivec == SGI_UART_VECTOR) {
99                 event_occurred = HUB_L((u64*)LOCAL_MMR_ADDR (SH_EVENT_OCCURRED));
100                 /* If the UART bit is set here, we may have received an
101                  * interrupt from the UART that the driver missed.  To
102                  * make sure, we IPI ourselves to force us to look again.
103                  */
104                 if (event_occurred & SH_EVENT_OCCURRED_UART_INT_MASK) {
105                         platform_send_ipi(smp_processor_id(), SGI_UART_VECTOR,
106                                           IA64_IPI_DM_INT, 0);
107                 }
108         }
109         __clear_bit(ivec, (volatile void *)pda->sn_in_service_ivecs);
110         if (sn_force_interrupt_flag)
111                 force_interrupt(irq);
112 }
113
114 static void sn_irq_info_free(struct rcu_head *head);
115
116 struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info,
117                                        nasid_t nasid, int slice)
118 {
119         int vector;
120         int cpuid;
121 #ifdef CONFIG_SMP
122         int cpuphys;
123 #endif
124         int64_t bridge;
125         int local_widget, status;
126         nasid_t local_nasid;
127         struct sn_irq_info *new_irq_info;
128         struct sn_pcibus_provider *pci_provider;
129
130         new_irq_info = kmalloc(sizeof(struct sn_irq_info), GFP_ATOMIC);
131         if (new_irq_info == NULL)
132                 return NULL;
133
134         memcpy(new_irq_info, sn_irq_info, sizeof(struct sn_irq_info));
135
136         bridge = (u64) new_irq_info->irq_bridge;
137         if (!bridge) {
138                 kfree(new_irq_info);
139                 return NULL; /* irq is not a device interrupt */
140         }
141
142         local_nasid = NASID_GET(bridge);
143
144         if (local_nasid & 1)
145                 local_widget = TIO_SWIN_WIDGETNUM(bridge);
146         else
147                 local_widget = SWIN_WIDGETNUM(bridge);
148
149         vector = sn_irq_info->irq_irq;
150         /* Free the old PROM new_irq_info structure */
151         sn_intr_free(local_nasid, local_widget, new_irq_info);
152         unregister_intr_pda(new_irq_info);
153
154         /* allocate a new PROM new_irq_info struct */
155         status = sn_intr_alloc(local_nasid, local_widget,
156                                new_irq_info, vector,
157                                nasid, slice);
158
159         /* SAL call failed */
160         if (status) {
161                 kfree(new_irq_info);
162                 return NULL;
163         }
164
165         /* Update kernels new_irq_info with new target info */
166         cpuid = nasid_slice_to_cpuid(new_irq_info->irq_nasid,
167                                      new_irq_info->irq_slice);
168         new_irq_info->irq_cpuid = cpuid;
169         register_intr_pda(new_irq_info);
170
171         pci_provider = sn_pci_provider[new_irq_info->irq_bridge_type];
172
173         /*
174          * If this represents a line interrupt, target it.  If it's
175          * an msi (irq_int_bit < 0), it's already targeted.
176          */
177         if (new_irq_info->irq_int_bit >= 0 &&
178             pci_provider && pci_provider->target_interrupt)
179                 (pci_provider->target_interrupt)(new_irq_info);
180
181         spin_lock(&sn_irq_info_lock);
182         list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
183         spin_unlock(&sn_irq_info_lock);
184         call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
185
186 #ifdef CONFIG_SMP
187         cpuphys = cpu_physical_id(cpuid);
188         set_irq_affinity_info((vector & 0xff), cpuphys, 0);
189 #endif
190
191         return new_irq_info;
192 }
193
194 static void sn_set_affinity_irq(unsigned int irq, cpumask_t mask)
195 {
196         struct sn_irq_info *sn_irq_info, *sn_irq_info_safe;
197         nasid_t nasid;
198         int slice;
199
200         nasid = cpuid_to_nasid(first_cpu(mask));
201         slice = cpuid_to_slice(first_cpu(mask));
202
203         list_for_each_entry_safe(sn_irq_info, sn_irq_info_safe,
204                                  sn_irq_lh[irq], list)
205                 (void)sn_retarget_vector(sn_irq_info, nasid, slice);
206 }
207
208 struct hw_interrupt_type irq_type_sn = {
209         .name           = "SN hub",
210         .startup        = sn_startup_irq,
211         .shutdown       = sn_shutdown_irq,
212         .enable         = sn_enable_irq,
213         .disable        = sn_disable_irq,
214         .ack            = sn_ack_irq,
215         .end            = sn_end_irq,
216         .set_affinity   = sn_set_affinity_irq
217 };
218
219 unsigned int sn_local_vector_to_irq(u8 vector)
220 {
221         return (CPU_VECTOR_TO_IRQ(smp_processor_id(), vector));
222 }
223
224 void sn_irq_init(void)
225 {
226         int i;
227         irq_desc_t *base_desc = irq_desc;
228
229         ia64_first_device_vector = IA64_SN2_FIRST_DEVICE_VECTOR;
230         ia64_last_device_vector = IA64_SN2_LAST_DEVICE_VECTOR;
231
232         for (i = 0; i < NR_IRQS; i++) {
233                 if (base_desc[i].chip == &no_irq_type) {
234                         base_desc[i].chip = &irq_type_sn;
235                 }
236         }
237 }
238
239 static void register_intr_pda(struct sn_irq_info *sn_irq_info)
240 {
241         int irq = sn_irq_info->irq_irq;
242         int cpu = sn_irq_info->irq_cpuid;
243
244         if (pdacpu(cpu)->sn_last_irq < irq) {
245                 pdacpu(cpu)->sn_last_irq = irq;
246         }
247
248         if (pdacpu(cpu)->sn_first_irq == 0 || pdacpu(cpu)->sn_first_irq > irq)
249                 pdacpu(cpu)->sn_first_irq = irq;
250 }
251
252 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
253 {
254         int irq = sn_irq_info->irq_irq;
255         int cpu = sn_irq_info->irq_cpuid;
256         struct sn_irq_info *tmp_irq_info;
257         int i, foundmatch;
258
259         rcu_read_lock();
260         if (pdacpu(cpu)->sn_last_irq == irq) {
261                 foundmatch = 0;
262                 for (i = pdacpu(cpu)->sn_last_irq - 1;
263                      i && !foundmatch; i--) {
264                         list_for_each_entry_rcu(tmp_irq_info,
265                                                 sn_irq_lh[i],
266                                                 list) {
267                                 if (tmp_irq_info->irq_cpuid == cpu) {
268                                         foundmatch = 1;
269                                         break;
270                                 }
271                         }
272                 }
273                 pdacpu(cpu)->sn_last_irq = i;
274         }
275
276         if (pdacpu(cpu)->sn_first_irq == irq) {
277                 foundmatch = 0;
278                 for (i = pdacpu(cpu)->sn_first_irq + 1;
279                      i < NR_IRQS && !foundmatch; i++) {
280                         list_for_each_entry_rcu(tmp_irq_info,
281                                                 sn_irq_lh[i],
282                                                 list) {
283                                 if (tmp_irq_info->irq_cpuid == cpu) {
284                                         foundmatch = 1;
285                                         break;
286                                 }
287                         }
288                 }
289                 pdacpu(cpu)->sn_first_irq = ((i == NR_IRQS) ? 0 : i);
290         }
291         rcu_read_unlock();
292 }
293
294 static void sn_irq_info_free(struct rcu_head *head)
295 {
296         struct sn_irq_info *sn_irq_info;
297
298         sn_irq_info = container_of(head, struct sn_irq_info, rcu);
299         kfree(sn_irq_info);
300 }
301
302 void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
303 {
304         nasid_t nasid = sn_irq_info->irq_nasid;
305         int slice = sn_irq_info->irq_slice;
306         int cpu = nasid_slice_to_cpuid(nasid, slice);
307 #ifdef CONFIG_SMP
308         int cpuphys;
309 #endif
310
311         pci_dev_get(pci_dev);
312         sn_irq_info->irq_cpuid = cpu;
313         sn_irq_info->irq_pciioinfo = SN_PCIDEV_INFO(pci_dev);
314
315         /* link it into the sn_irq[irq] list */
316         spin_lock(&sn_irq_info_lock);
317         list_add_rcu(&sn_irq_info->list, sn_irq_lh[sn_irq_info->irq_irq]);
318         reserve_irq_vector(sn_irq_info->irq_irq);
319         spin_unlock(&sn_irq_info_lock);
320
321         register_intr_pda(sn_irq_info);
322 #ifdef CONFIG_SMP
323         cpuphys = cpu_physical_id(cpu);
324         set_irq_affinity_info(sn_irq_info->irq_irq, cpuphys, 0);
325 #endif
326 }
327
328 void sn_irq_unfixup(struct pci_dev *pci_dev)
329 {
330         struct sn_irq_info *sn_irq_info;
331
332         /* Only cleanup IRQ stuff if this device has a host bus context */
333         if (!SN_PCIDEV_BUSSOFT(pci_dev))
334                 return;
335
336         sn_irq_info = SN_PCIDEV_INFO(pci_dev)->pdi_sn_irq_info;
337         if (!sn_irq_info)
338                 return;
339         if (!sn_irq_info->irq_irq) {
340                 kfree(sn_irq_info);
341                 return;
342         }
343
344         unregister_intr_pda(sn_irq_info);
345         spin_lock(&sn_irq_info_lock);
346         list_del_rcu(&sn_irq_info->list);
347         spin_unlock(&sn_irq_info_lock);
348         if (list_empty(sn_irq_lh[sn_irq_info->irq_irq]))
349                 free_irq_vector(sn_irq_info->irq_irq);
350         call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
351         pci_dev_put(pci_dev);
352
353 }
354
355 static inline void
356 sn_call_force_intr_provider(struct sn_irq_info *sn_irq_info)
357 {
358         struct sn_pcibus_provider *pci_provider;
359
360         pci_provider = sn_pci_provider[sn_irq_info->irq_bridge_type];
361         if (pci_provider && pci_provider->force_interrupt)
362                 (*pci_provider->force_interrupt)(sn_irq_info);
363 }
364
365 static void force_interrupt(int irq)
366 {
367         struct sn_irq_info *sn_irq_info;
368
369         if (!sn_ioif_inited)
370                 return;
371
372         rcu_read_lock();
373         list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[irq], list)
374                 sn_call_force_intr_provider(sn_irq_info);
375
376         rcu_read_unlock();
377 }
378
379 /*
380  * Check for lost interrupts.  If the PIC int_status reg. says that
381  * an interrupt has been sent, but not handled, and the interrupt
382  * is not pending in either the cpu irr regs or in the soft irr regs,
383  * and the interrupt is not in service, then the interrupt may have
384  * been lost.  Force an interrupt on that pin.  It is possible that
385  * the interrupt is in flight, so we may generate a spurious interrupt,
386  * but we should never miss a real lost interrupt.
387  */
388 static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
389 {
390         u64 regval;
391         struct pcidev_info *pcidev_info;
392         struct pcibus_info *pcibus_info;
393
394         /*
395          * Bridge types attached to TIO (anything but PIC) do not need this WAR
396          * since they do not target Shub II interrupt registers.  If that
397          * ever changes, this check needs to accomodate.
398          */
399         if (sn_irq_info->irq_bridge_type != PCIIO_ASIC_TYPE_PIC)
400                 return;
401
402         pcidev_info = (struct pcidev_info *)sn_irq_info->irq_pciioinfo;
403         if (!pcidev_info)
404                 return;
405
406         pcibus_info =
407             (struct pcibus_info *)pcidev_info->pdi_host_pcidev_info->
408             pdi_pcibus_info;
409         regval = pcireg_intr_status_get(pcibus_info);
410
411         if (!ia64_get_irr(irq_to_vector(irq))) {
412                 if (!test_bit(irq, pda->sn_in_service_ivecs)) {
413                         regval &= 0xff;
414                         if (sn_irq_info->irq_int_bit & regval &
415                             sn_irq_info->irq_last_intr) {
416                                 regval &= ~(sn_irq_info->irq_int_bit & regval);
417                                 sn_call_force_intr_provider(sn_irq_info);
418                         }
419                 }
420         }
421         sn_irq_info->irq_last_intr = regval;
422 }
423
424 void sn_lb_int_war_check(void)
425 {
426         struct sn_irq_info *sn_irq_info;
427         int i;
428
429         if (!sn_ioif_inited || pda->sn_first_irq == 0)
430                 return;
431
432         rcu_read_lock();
433         for (i = pda->sn_first_irq; i <= pda->sn_last_irq; i++) {
434                 list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[i], list) {
435                         sn_check_intr(i, sn_irq_info);
436                 }
437         }
438         rcu_read_unlock();
439 }
440
441 void __init sn_irq_lh_init(void)
442 {
443         int i;
444
445         sn_irq_lh = kmalloc(sizeof(struct list_head *) * NR_IRQS, GFP_KERNEL);
446         if (!sn_irq_lh)
447                 panic("SN PCI INIT: Failed to allocate memory for PCI init\n");
448
449         for (i = 0; i < NR_IRQS; i++) {
450                 sn_irq_lh[i] = kmalloc(sizeof(struct list_head), GFP_KERNEL);
451                 if (!sn_irq_lh[i])
452                         panic("SN PCI INIT: Failed IRQ memory allocation\n");
453
454                 INIT_LIST_HEAD(sn_irq_lh[i]);
455         }
456 }