[IA64] sparse cleanups
[linux-2.6.git] / 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 cpuphys;
121         int64_t bridge;
122         int local_widget, status;
123         nasid_t local_nasid;
124         struct sn_irq_info *new_irq_info;
125         struct sn_pcibus_provider *pci_provider;
126
127         new_irq_info = kmalloc(sizeof(struct sn_irq_info), GFP_ATOMIC);
128         if (new_irq_info == NULL)
129                 return NULL;
130
131         memcpy(new_irq_info, sn_irq_info, sizeof(struct sn_irq_info));
132
133         bridge = (u64) new_irq_info->irq_bridge;
134         if (!bridge) {
135                 kfree(new_irq_info);
136                 return NULL; /* irq is not a device interrupt */
137         }
138
139         local_nasid = NASID_GET(bridge);
140
141         if (local_nasid & 1)
142                 local_widget = TIO_SWIN_WIDGETNUM(bridge);
143         else
144                 local_widget = SWIN_WIDGETNUM(bridge);
145
146         vector = sn_irq_info->irq_irq;
147         /* Free the old PROM new_irq_info structure */
148         sn_intr_free(local_nasid, local_widget, new_irq_info);
149         /* Update kernels new_irq_info with new target info */
150         unregister_intr_pda(new_irq_info);
151
152         /* allocate a new PROM new_irq_info struct */
153         status = sn_intr_alloc(local_nasid, local_widget,
154                                new_irq_info, vector,
155                                nasid, slice);
156
157         /* SAL call failed */
158         if (status) {
159                 kfree(new_irq_info);
160                 return NULL;
161         }
162
163         cpuphys = nasid_slice_to_cpuid(nasid, slice);
164         new_irq_info->irq_cpuid = cpuphys;
165         register_intr_pda(new_irq_info);
166
167         pci_provider = sn_pci_provider[new_irq_info->irq_bridge_type];
168
169         /*
170          * If this represents a line interrupt, target it.  If it's
171          * an msi (irq_int_bit < 0), it's already targeted.
172          */
173         if (new_irq_info->irq_int_bit >= 0 &&
174             pci_provider && pci_provider->target_interrupt)
175                 (pci_provider->target_interrupt)(new_irq_info);
176
177         spin_lock(&sn_irq_info_lock);
178         list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
179         spin_unlock(&sn_irq_info_lock);
180         call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
181
182 #ifdef CONFIG_SMP
183         set_irq_affinity_info((vector & 0xff), cpuphys, 0);
184 #endif
185
186         return new_irq_info;
187 }
188
189 static void sn_set_affinity_irq(unsigned int irq, cpumask_t mask)
190 {
191         struct sn_irq_info *sn_irq_info, *sn_irq_info_safe;
192         nasid_t nasid;
193         int slice;
194
195         nasid = cpuid_to_nasid(first_cpu(mask));
196         slice = cpuid_to_slice(first_cpu(mask));
197
198         list_for_each_entry_safe(sn_irq_info, sn_irq_info_safe,
199                                  sn_irq_lh[irq], list)
200                 (void)sn_retarget_vector(sn_irq_info, nasid, slice);
201 }
202
203 struct hw_interrupt_type irq_type_sn = {
204         .name           = "SN hub",
205         .startup        = sn_startup_irq,
206         .shutdown       = sn_shutdown_irq,
207         .enable         = sn_enable_irq,
208         .disable        = sn_disable_irq,
209         .ack            = sn_ack_irq,
210         .end            = sn_end_irq,
211         .set_affinity   = sn_set_affinity_irq
212 };
213
214 unsigned int sn_local_vector_to_irq(u8 vector)
215 {
216         return (CPU_VECTOR_TO_IRQ(smp_processor_id(), vector));
217 }
218
219 void sn_irq_init(void)
220 {
221         int i;
222         irq_desc_t *base_desc = irq_desc;
223
224         ia64_first_device_vector = IA64_SN2_FIRST_DEVICE_VECTOR;
225         ia64_last_device_vector = IA64_SN2_LAST_DEVICE_VECTOR;
226
227         for (i = 0; i < NR_IRQS; i++) {
228                 if (base_desc[i].chip == &no_irq_type) {
229                         base_desc[i].chip = &irq_type_sn;
230                 }
231         }
232 }
233
234 static void register_intr_pda(struct sn_irq_info *sn_irq_info)
235 {
236         int irq = sn_irq_info->irq_irq;
237         int cpu = sn_irq_info->irq_cpuid;
238
239         if (pdacpu(cpu)->sn_last_irq < irq) {
240                 pdacpu(cpu)->sn_last_irq = irq;
241         }
242
243         if (pdacpu(cpu)->sn_first_irq == 0 || pdacpu(cpu)->sn_first_irq > irq)
244                 pdacpu(cpu)->sn_first_irq = irq;
245 }
246
247 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
248 {
249         int irq = sn_irq_info->irq_irq;
250         int cpu = sn_irq_info->irq_cpuid;
251         struct sn_irq_info *tmp_irq_info;
252         int i, foundmatch;
253
254         rcu_read_lock();
255         if (pdacpu(cpu)->sn_last_irq == irq) {
256                 foundmatch = 0;
257                 for (i = pdacpu(cpu)->sn_last_irq - 1;
258                      i && !foundmatch; i--) {
259                         list_for_each_entry_rcu(tmp_irq_info,
260                                                 sn_irq_lh[i],
261                                                 list) {
262                                 if (tmp_irq_info->irq_cpuid == cpu) {
263                                         foundmatch = 1;
264                                         break;
265                                 }
266                         }
267                 }
268                 pdacpu(cpu)->sn_last_irq = i;
269         }
270
271         if (pdacpu(cpu)->sn_first_irq == irq) {
272                 foundmatch = 0;
273                 for (i = pdacpu(cpu)->sn_first_irq + 1;
274                      i < NR_IRQS && !foundmatch; i++) {
275                         list_for_each_entry_rcu(tmp_irq_info,
276                                                 sn_irq_lh[i],
277                                                 list) {
278                                 if (tmp_irq_info->irq_cpuid == cpu) {
279                                         foundmatch = 1;
280                                         break;
281                                 }
282                         }
283                 }
284                 pdacpu(cpu)->sn_first_irq = ((i == NR_IRQS) ? 0 : i);
285         }
286         rcu_read_unlock();
287 }
288
289 static void sn_irq_info_free(struct rcu_head *head)
290 {
291         struct sn_irq_info *sn_irq_info;
292
293         sn_irq_info = container_of(head, struct sn_irq_info, rcu);
294         kfree(sn_irq_info);
295 }
296
297 void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
298 {
299         nasid_t nasid = sn_irq_info->irq_nasid;
300         int slice = sn_irq_info->irq_slice;
301         int cpu = nasid_slice_to_cpuid(nasid, slice);
302
303         pci_dev_get(pci_dev);
304         sn_irq_info->irq_cpuid = cpu;
305         sn_irq_info->irq_pciioinfo = SN_PCIDEV_INFO(pci_dev);
306
307         /* link it into the sn_irq[irq] list */
308         spin_lock(&sn_irq_info_lock);
309         list_add_rcu(&sn_irq_info->list, sn_irq_lh[sn_irq_info->irq_irq]);
310         reserve_irq_vector(sn_irq_info->irq_irq);
311         spin_unlock(&sn_irq_info_lock);
312
313         register_intr_pda(sn_irq_info);
314 }
315
316 void sn_irq_unfixup(struct pci_dev *pci_dev)
317 {
318         struct sn_irq_info *sn_irq_info;
319
320         /* Only cleanup IRQ stuff if this device has a host bus context */
321         if (!SN_PCIDEV_BUSSOFT(pci_dev))
322                 return;
323
324         sn_irq_info = SN_PCIDEV_INFO(pci_dev)->pdi_sn_irq_info;
325         if (!sn_irq_info)
326                 return;
327         if (!sn_irq_info->irq_irq) {
328                 kfree(sn_irq_info);
329                 return;
330         }
331
332         unregister_intr_pda(sn_irq_info);
333         spin_lock(&sn_irq_info_lock);
334         list_del_rcu(&sn_irq_info->list);
335         spin_unlock(&sn_irq_info_lock);
336         if (list_empty(sn_irq_lh[sn_irq_info->irq_irq]))
337                 free_irq_vector(sn_irq_info->irq_irq);
338         call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
339         pci_dev_put(pci_dev);
340
341 }
342
343 static inline void
344 sn_call_force_intr_provider(struct sn_irq_info *sn_irq_info)
345 {
346         struct sn_pcibus_provider *pci_provider;
347
348         pci_provider = sn_pci_provider[sn_irq_info->irq_bridge_type];
349         if (pci_provider && pci_provider->force_interrupt)
350                 (*pci_provider->force_interrupt)(sn_irq_info);
351 }
352
353 static void force_interrupt(int irq)
354 {
355         struct sn_irq_info *sn_irq_info;
356
357         if (!sn_ioif_inited)
358                 return;
359
360         rcu_read_lock();
361         list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[irq], list)
362                 sn_call_force_intr_provider(sn_irq_info);
363
364         rcu_read_unlock();
365 }
366
367 /*
368  * Check for lost interrupts.  If the PIC int_status reg. says that
369  * an interrupt has been sent, but not handled, and the interrupt
370  * is not pending in either the cpu irr regs or in the soft irr regs,
371  * and the interrupt is not in service, then the interrupt may have
372  * been lost.  Force an interrupt on that pin.  It is possible that
373  * the interrupt is in flight, so we may generate a spurious interrupt,
374  * but we should never miss a real lost interrupt.
375  */
376 static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
377 {
378         u64 regval;
379         struct pcidev_info *pcidev_info;
380         struct pcibus_info *pcibus_info;
381
382         /*
383          * Bridge types attached to TIO (anything but PIC) do not need this WAR
384          * since they do not target Shub II interrupt registers.  If that
385          * ever changes, this check needs to accomodate.
386          */
387         if (sn_irq_info->irq_bridge_type != PCIIO_ASIC_TYPE_PIC)
388                 return;
389
390         pcidev_info = (struct pcidev_info *)sn_irq_info->irq_pciioinfo;
391         if (!pcidev_info)
392                 return;
393
394         pcibus_info =
395             (struct pcibus_info *)pcidev_info->pdi_host_pcidev_info->
396             pdi_pcibus_info;
397         regval = pcireg_intr_status_get(pcibus_info);
398
399         if (!ia64_get_irr(irq_to_vector(irq))) {
400                 if (!test_bit(irq, pda->sn_in_service_ivecs)) {
401                         regval &= 0xff;
402                         if (sn_irq_info->irq_int_bit & regval &
403                             sn_irq_info->irq_last_intr) {
404                                 regval &= ~(sn_irq_info->irq_int_bit & regval);
405                                 sn_call_force_intr_provider(sn_irq_info);
406                         }
407                 }
408         }
409         sn_irq_info->irq_last_intr = regval;
410 }
411
412 void sn_lb_int_war_check(void)
413 {
414         struct sn_irq_info *sn_irq_info;
415         int i;
416
417         if (!sn_ioif_inited || pda->sn_first_irq == 0)
418                 return;
419
420         rcu_read_lock();
421         for (i = pda->sn_first_irq; i <= pda->sn_last_irq; i++) {
422                 list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[i], list) {
423                         sn_check_intr(i, sn_irq_info);
424                 }
425         }
426         rcu_read_unlock();
427 }
428
429 void __init sn_irq_lh_init(void)
430 {
431         int i;
432
433         sn_irq_lh = kmalloc(sizeof(struct list_head *) * NR_IRQS, GFP_KERNEL);
434         if (!sn_irq_lh)
435                 panic("SN PCI INIT: Failed to allocate memory for PCI init\n");
436
437         for (i = 0; i < NR_IRQS; i++) {
438                 sn_irq_lh[i] = kmalloc(sizeof(struct list_head), GFP_KERNEL);
439                 if (!sn_irq_lh[i])
440                         panic("SN PCI INIT: Failed IRQ memory allocation\n");
441
442                 INIT_LIST_HEAD(sn_irq_lh[i]);
443         }
444 }