Merge linux-2.6 into linux-acpi-2.6 test
[linux-3.10.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) 2000-2005 Silicon Graphics, Inc.  All Rights Reserved.
9  */
10
11 #include <linux/irq.h>
12 #include <linux/spinlock.h>
13 #include <asm/sn/addrs.h>
14 #include <asm/sn/arch.h>
15 #include <asm/sn/intr.h>
16 #include <asm/sn/pcibr_provider.h>
17 #include <asm/sn/pcibus_provider_defs.h>
18 #include <asm/sn/pcidev.h>
19 #include <asm/sn/shub_mmr.h>
20 #include <asm/sn/sn_sal.h>
21
22 static void force_interrupt(int irq);
23 static void register_intr_pda(struct sn_irq_info *sn_irq_info);
24 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info);
25
26 int sn_force_interrupt_flag = 1;
27 extern int sn_ioif_inited;
28 static struct list_head **sn_irq_lh;
29 static spinlock_t sn_irq_info_lock = SPIN_LOCK_UNLOCKED; /* non-IRQ lock */
30
31 static inline uint64_t sn_intr_alloc(nasid_t local_nasid, int local_widget,
32                                      u64 sn_irq_info,
33                                      int req_irq, nasid_t req_nasid,
34                                      int req_slice)
35 {
36         struct ia64_sal_retval ret_stuff;
37         ret_stuff.status = 0;
38         ret_stuff.v0 = 0;
39
40         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
41                         (u64) SAL_INTR_ALLOC, (u64) local_nasid,
42                         (u64) local_widget, (u64) sn_irq_info, (u64) req_irq,
43                         (u64) req_nasid, (u64) req_slice);
44         return ret_stuff.status;
45 }
46
47 static inline void sn_intr_free(nasid_t local_nasid, int local_widget,
48                                 struct sn_irq_info *sn_irq_info)
49 {
50         struct ia64_sal_retval ret_stuff;
51         ret_stuff.status = 0;
52         ret_stuff.v0 = 0;
53
54         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
55                         (u64) SAL_INTR_FREE, (u64) local_nasid,
56                         (u64) local_widget, (u64) sn_irq_info->irq_irq,
57                         (u64) sn_irq_info->irq_cookie, 0, 0);
58 }
59
60 static unsigned int sn_startup_irq(unsigned int irq)
61 {
62         return 0;
63 }
64
65 static void sn_shutdown_irq(unsigned int irq)
66 {
67 }
68
69 static void sn_disable_irq(unsigned int irq)
70 {
71 }
72
73 static void sn_enable_irq(unsigned int irq)
74 {
75 }
76
77 static void sn_ack_irq(unsigned int irq)
78 {
79         u64 event_occurred, mask = 0;
80
81         irq = irq & 0xff;
82         event_occurred =
83             HUB_L((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED));
84         mask = event_occurred & SH_ALL_INT_MASK;
85         HUB_S((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS),
86               mask);
87         __set_bit(irq, (volatile void *)pda->sn_in_service_ivecs);
88
89         move_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 static void sn_set_affinity_irq(unsigned int irq, cpumask_t mask)
117 {
118         struct sn_irq_info *sn_irq_info, *sn_irq_info_safe;
119         int cpuid, cpuphys;
120
121         cpuid = first_cpu(mask);
122         cpuphys = cpu_physical_id(cpuid);
123
124         list_for_each_entry_safe(sn_irq_info, sn_irq_info_safe,
125                                  sn_irq_lh[irq], list) {
126                 uint64_t bridge;
127                 int local_widget, status;
128                 nasid_t local_nasid;
129                 struct sn_irq_info *new_irq_info;
130                 struct sn_pcibus_provider *pci_provider;
131
132                 new_irq_info = kmalloc(sizeof(struct sn_irq_info), GFP_ATOMIC);
133                 if (new_irq_info == NULL)
134                         break;
135                 memcpy(new_irq_info, sn_irq_info, sizeof(struct sn_irq_info));
136
137                 bridge = (uint64_t) new_irq_info->irq_bridge;
138                 if (!bridge) {
139                         kfree(new_irq_info);
140                         break; /* irq is not a device interrupt */
141                 }
142
143                 local_nasid = NASID_GET(bridge);
144
145                 if (local_nasid & 1)
146                         local_widget = TIO_SWIN_WIDGETNUM(bridge);
147                 else
148                         local_widget = SWIN_WIDGETNUM(bridge);
149
150                 /* Free the old PROM new_irq_info structure */
151                 sn_intr_free(local_nasid, local_widget, new_irq_info);
152                 /* Update kernels new_irq_info with new target info */
153                 unregister_intr_pda(new_irq_info);
154
155                 /* allocate a new PROM new_irq_info struct */
156                 status = sn_intr_alloc(local_nasid, local_widget,
157                                        __pa(new_irq_info), irq,
158                                        cpuid_to_nasid(cpuid),
159                                        cpuid_to_slice(cpuid));
160
161                 /* SAL call failed */
162                 if (status) {
163                         kfree(new_irq_info);
164                         break;
165                 }
166
167                 new_irq_info->irq_cpuid = cpuid;
168                 register_intr_pda(new_irq_info);
169
170                 pci_provider = sn_pci_provider[new_irq_info->irq_bridge_type];
171                 if (pci_provider && pci_provider->target_interrupt)
172                         (pci_provider->target_interrupt)(new_irq_info);
173
174                 spin_lock(&sn_irq_info_lock);
175                 list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
176                 spin_unlock(&sn_irq_info_lock);
177                 call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
178
179 #ifdef CONFIG_SMP
180                 set_irq_affinity_info((irq & 0xff), cpuphys, 0);
181 #endif
182         }
183 }
184
185 struct hw_interrupt_type irq_type_sn = {
186         .typename       = "SN hub",
187         .startup        = sn_startup_irq,
188         .shutdown       = sn_shutdown_irq,
189         .enable         = sn_enable_irq,
190         .disable        = sn_disable_irq,
191         .ack            = sn_ack_irq,
192         .end            = sn_end_irq,
193         .set_affinity   = sn_set_affinity_irq
194 };
195
196 unsigned int sn_local_vector_to_irq(u8 vector)
197 {
198         return (CPU_VECTOR_TO_IRQ(smp_processor_id(), vector));
199 }
200
201 void sn_irq_init(void)
202 {
203         int i;
204         irq_desc_t *base_desc = irq_desc;
205
206         for (i = 0; i < NR_IRQS; i++) {
207                 if (base_desc[i].handler == &no_irq_type) {
208                         base_desc[i].handler = &irq_type_sn;
209                 }
210         }
211 }
212
213 static void register_intr_pda(struct sn_irq_info *sn_irq_info)
214 {
215         int irq = sn_irq_info->irq_irq;
216         int cpu = sn_irq_info->irq_cpuid;
217
218         if (pdacpu(cpu)->sn_last_irq < irq) {
219                 pdacpu(cpu)->sn_last_irq = irq;
220         }
221
222         if (pdacpu(cpu)->sn_first_irq == 0 || pdacpu(cpu)->sn_first_irq > irq) {
223                 pdacpu(cpu)->sn_first_irq = irq;
224         }
225 }
226
227 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
228 {
229         int irq = sn_irq_info->irq_irq;
230         int cpu = sn_irq_info->irq_cpuid;
231         struct sn_irq_info *tmp_irq_info;
232         int i, foundmatch;
233
234         rcu_read_lock();
235         if (pdacpu(cpu)->sn_last_irq == irq) {
236                 foundmatch = 0;
237                 for (i = pdacpu(cpu)->sn_last_irq - 1;
238                      i && !foundmatch; i--) {
239                         list_for_each_entry_rcu(tmp_irq_info,
240                                                 sn_irq_lh[i],
241                                                 list) {
242                                 if (tmp_irq_info->irq_cpuid == cpu) {
243                                         foundmatch = 1;
244                                         break;
245                                 }
246                         }
247                 }
248                 pdacpu(cpu)->sn_last_irq = i;
249         }
250
251         if (pdacpu(cpu)->sn_first_irq == irq) {
252                 foundmatch = 0;
253                 for (i = pdacpu(cpu)->sn_first_irq + 1;
254                      i < NR_IRQS && !foundmatch; i++) {
255                         list_for_each_entry_rcu(tmp_irq_info,
256                                                 sn_irq_lh[i],
257                                                 list) {
258                                 if (tmp_irq_info->irq_cpuid == cpu) {
259                                         foundmatch = 1;
260                                         break;
261                                 }
262                         }
263                 }
264                 pdacpu(cpu)->sn_first_irq = ((i == NR_IRQS) ? 0 : i);
265         }
266         rcu_read_unlock();
267 }
268
269 static void sn_irq_info_free(struct rcu_head *head)
270 {
271         struct sn_irq_info *sn_irq_info;
272
273         sn_irq_info = container_of(head, struct sn_irq_info, rcu);
274         kfree(sn_irq_info);
275 }
276
277 void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
278 {
279         nasid_t nasid = sn_irq_info->irq_nasid;
280         int slice = sn_irq_info->irq_slice;
281         int cpu = nasid_slice_to_cpuid(nasid, slice);
282
283         pci_dev_get(pci_dev);
284         sn_irq_info->irq_cpuid = cpu;
285         sn_irq_info->irq_pciioinfo = SN_PCIDEV_INFO(pci_dev);
286
287         /* link it into the sn_irq[irq] list */
288         spin_lock(&sn_irq_info_lock);
289         list_add_rcu(&sn_irq_info->list, sn_irq_lh[sn_irq_info->irq_irq]);
290         spin_unlock(&sn_irq_info_lock);
291
292         (void)register_intr_pda(sn_irq_info);
293 }
294
295 void sn_irq_unfixup(struct pci_dev *pci_dev)
296 {
297         struct sn_irq_info *sn_irq_info;
298
299         /* Only cleanup IRQ stuff if this device has a host bus context */
300         if (!SN_PCIDEV_BUSSOFT(pci_dev))
301                 return;
302
303         sn_irq_info = SN_PCIDEV_INFO(pci_dev)->pdi_sn_irq_info;
304         if (!sn_irq_info || !sn_irq_info->irq_irq) {
305                 kfree(sn_irq_info);
306                 return;
307         }
308
309         unregister_intr_pda(sn_irq_info);
310         spin_lock(&sn_irq_info_lock);
311         list_del_rcu(&sn_irq_info->list);
312         spin_unlock(&sn_irq_info_lock);
313         call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
314         pci_dev_put(pci_dev);
315 }
316
317 static inline void
318 sn_call_force_intr_provider(struct sn_irq_info *sn_irq_info)
319 {
320         struct sn_pcibus_provider *pci_provider;
321
322         pci_provider = sn_pci_provider[sn_irq_info->irq_bridge_type];
323         if (pci_provider && pci_provider->force_interrupt)
324                 (*pci_provider->force_interrupt)(sn_irq_info);
325 }
326
327 static void force_interrupt(int irq)
328 {
329         struct sn_irq_info *sn_irq_info;
330
331         if (!sn_ioif_inited)
332                 return;
333
334         rcu_read_lock();
335         list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[irq], list)
336                 sn_call_force_intr_provider(sn_irq_info);
337
338         rcu_read_unlock();
339 }
340
341 /*
342  * Check for lost interrupts.  If the PIC int_status reg. says that
343  * an interrupt has been sent, but not handled, and the interrupt
344  * is not pending in either the cpu irr regs or in the soft irr regs,
345  * and the interrupt is not in service, then the interrupt may have
346  * been lost.  Force an interrupt on that pin.  It is possible that
347  * the interrupt is in flight, so we may generate a spurious interrupt,
348  * but we should never miss a real lost interrupt.
349  */
350 static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
351 {
352         uint64_t regval;
353         int irr_reg_num;
354         int irr_bit;
355         uint64_t irr_reg;
356         struct pcidev_info *pcidev_info;
357         struct pcibus_info *pcibus_info;
358
359         /*
360          * Bridge types attached to TIO (anything but PIC) do not need this WAR
361          * since they do not target Shub II interrupt registers.  If that
362          * ever changes, this check needs to accomodate.
363          */
364         if (sn_irq_info->irq_bridge_type != PCIIO_ASIC_TYPE_PIC)
365                 return;
366
367         pcidev_info = (struct pcidev_info *)sn_irq_info->irq_pciioinfo;
368         if (!pcidev_info)
369                 return;
370
371         pcibus_info =
372             (struct pcibus_info *)pcidev_info->pdi_host_pcidev_info->
373             pdi_pcibus_info;
374         regval = pcireg_intr_status_get(pcibus_info);
375
376         irr_reg_num = irq_to_vector(irq) / 64;
377         irr_bit = irq_to_vector(irq) % 64;
378         switch (irr_reg_num) {
379         case 0:
380                 irr_reg = ia64_getreg(_IA64_REG_CR_IRR0);
381                 break;
382         case 1:
383                 irr_reg = ia64_getreg(_IA64_REG_CR_IRR1);
384                 break;
385         case 2:
386                 irr_reg = ia64_getreg(_IA64_REG_CR_IRR2);
387                 break;
388         case 3:
389                 irr_reg = ia64_getreg(_IA64_REG_CR_IRR3);
390                 break;
391         }
392         if (!test_bit(irr_bit, &irr_reg)) {
393                 if (!test_bit(irq, pda->sn_in_service_ivecs)) {
394                         regval &= 0xff;
395                         if (sn_irq_info->irq_int_bit & regval &
396                             sn_irq_info->irq_last_intr) {
397                                 regval &= ~(sn_irq_info->irq_int_bit & regval);
398                                 sn_call_force_intr_provider(sn_irq_info);
399                         }
400                 }
401         }
402         sn_irq_info->irq_last_intr = regval;
403 }
404
405 void sn_lb_int_war_check(void)
406 {
407         struct sn_irq_info *sn_irq_info;
408         int i;
409
410         if (!sn_ioif_inited || pda->sn_first_irq == 0)
411                 return;
412
413         rcu_read_lock();
414         for (i = pda->sn_first_irq; i <= pda->sn_last_irq; i++) {
415                 list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[i], list) {
416                         sn_check_intr(i, sn_irq_info);
417                 }
418         }
419         rcu_read_unlock();
420 }
421
422 void sn_irq_lh_init(void)
423 {
424         int i;
425
426         sn_irq_lh = kmalloc(sizeof(struct list_head *) * NR_IRQS, GFP_KERNEL);
427         if (!sn_irq_lh)
428                 panic("SN PCI INIT: Failed to allocate memory for PCI init\n");
429
430         for (i = 0; i < NR_IRQS; i++) {
431                 sn_irq_lh[i] = kmalloc(sizeof(struct list_head), GFP_KERNEL);
432                 if (!sn_irq_lh[i])
433                         panic("SN PCI INIT: Failed IRQ memory allocation\n");
434
435                 INIT_LIST_HEAD(sn_irq_lh[i]);
436         }
437
438 }