Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright 2011 IBM Corporation.
4 */
5#include <linux/types.h>
6#include <linux/threads.h>
7#include <linux/kernel.h>
8#include <linux/irq.h>
9#include <linux/irqdomain.h>
10#include <linux/debugfs.h>
11#include <linux/smp.h>
12#include <linux/interrupt.h>
13#include <linux/seq_file.h>
14#include <linux/init.h>
15#include <linux/cpu.h>
16#include <linux/of.h>
17#include <linux/slab.h>
18#include <linux/spinlock.h>
19#include <linux/delay.h>
20
21#include <asm/io.h>
22#include <asm/smp.h>
23#include <asm/machdep.h>
24#include <asm/irq.h>
25#include <asm/errno.h>
26#include <asm/rtas.h>
27#include <asm/xics.h>
28#include <asm/firmware.h>
29
30/* Globals common to all ICP/ICS implementations */
31const struct icp_ops *icp_ops;
32
33unsigned int xics_default_server = 0xff;
34unsigned int xics_default_distrib_server = 0;
35unsigned int xics_interrupt_server_size = 8;
36
37DEFINE_PER_CPU(struct xics_cppr, xics_cppr);
38
39struct irq_domain *xics_host;
40
41static struct ics *xics_ics;
42
43void xics_update_irq_servers(void)
44{
45 int i, j;
46 struct device_node *np;
47 u32 ilen;
48 const __be32 *ireg;
49 u32 hcpuid;
50
51 /* Find the server numbers for the boot cpu. */
52 np = of_get_cpu_node(boot_cpuid, NULL);
53 BUG_ON(!np);
54
55 hcpuid = get_hard_smp_processor_id(boot_cpuid);
56 xics_default_server = xics_default_distrib_server = hcpuid;
57
58 pr_devel("xics: xics_default_server = 0x%x\n", xics_default_server);
59
60 ireg = of_get_property(np, "ibm,ppc-interrupt-gserver#s", &ilen);
61 if (!ireg) {
62 of_node_put(np);
63 return;
64 }
65
66 i = ilen / sizeof(int);
67
68 /* Global interrupt distribution server is specified in the last
69 * entry of "ibm,ppc-interrupt-gserver#s" property. Get the last
70 * entry fom this property for current boot cpu id and use it as
71 * default distribution server
72 */
73 for (j = 0; j < i; j += 2) {
74 if (be32_to_cpu(ireg[j]) == hcpuid) {
75 xics_default_distrib_server = be32_to_cpu(ireg[j+1]);
76 break;
77 }
78 }
79 pr_devel("xics: xics_default_distrib_server = 0x%x\n",
80 xics_default_distrib_server);
81 of_node_put(np);
82}
83
84/* GIQ stuff, currently only supported on RTAS setups, will have
85 * to be sorted properly for bare metal
86 */
87void xics_set_cpu_giq(unsigned int gserver, unsigned int join)
88{
89#ifdef CONFIG_PPC_RTAS
90 int index;
91 int status;
92
93 if (!rtas_indicator_present(GLOBAL_INTERRUPT_QUEUE, NULL))
94 return;
95
96 index = (1UL << xics_interrupt_server_size) - 1 - gserver;
97
98 status = rtas_set_indicator_fast(GLOBAL_INTERRUPT_QUEUE, index, join);
99
100 WARN(status < 0, "set-indicator(%d, %d, %u) returned %d\n",
101 GLOBAL_INTERRUPT_QUEUE, index, join, status);
102#endif
103}
104
105void xics_setup_cpu(void)
106{
107 icp_ops->set_priority(LOWEST_PRIORITY);
108
109 xics_set_cpu_giq(xics_default_distrib_server, 1);
110}
111
112void xics_mask_unknown_vec(unsigned int vec)
113{
114 pr_err("Interrupt 0x%x (real) is invalid, disabling it.\n", vec);
115
116 if (WARN_ON(!xics_ics))
117 return;
118 xics_ics->mask_unknown(xics_ics, vec);
119}
120
121
122#ifdef CONFIG_SMP
123
124static void __init xics_request_ipi(void)
125{
126 unsigned int ipi;
127
128 ipi = irq_create_mapping(xics_host, XICS_IPI);
129 BUG_ON(!ipi);
130
131 /*
132 * IPIs are marked IRQF_PERCPU. The handler was set in map.
133 */
134 BUG_ON(request_irq(ipi, icp_ops->ipi_action,
135 IRQF_NO_DEBUG | IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL));
136}
137
138void __init xics_smp_probe(void)
139{
140 /* Register all the IPIs */
141 xics_request_ipi();
142
143 /* Setup cause_ipi callback based on which ICP is used */
144 smp_ops->cause_ipi = icp_ops->cause_ipi;
145}
146
147#endif /* CONFIG_SMP */
148
149noinstr void xics_teardown_cpu(void)
150{
151 struct xics_cppr *os_cppr = this_cpu_ptr(&xics_cppr);
152
153 /*
154 * we have to reset the cppr index to 0 because we're
155 * not going to return from the IPI
156 */
157 os_cppr->index = 0;
158 icp_ops->set_priority(0);
159 icp_ops->teardown_cpu();
160}
161
162noinstr void xics_kexec_teardown_cpu(int secondary)
163{
164 xics_teardown_cpu();
165
166 icp_ops->flush_ipi();
167
168 /*
169 * Some machines need to have at least one cpu in the GIQ,
170 * so leave the master cpu in the group.
171 */
172 if (secondary)
173 xics_set_cpu_giq(xics_default_distrib_server, 0);
174}
175
176
177#ifdef CONFIG_HOTPLUG_CPU
178
179/* Interrupts are disabled. */
180void xics_migrate_irqs_away(void)
181{
182 int cpu = smp_processor_id(), hw_cpu = hard_smp_processor_id();
183 unsigned int irq, virq;
184 struct irq_desc *desc;
185
186 pr_debug("%s: CPU %u\n", __func__, cpu);
187
188 /* If we used to be the default server, move to the new "boot_cpuid" */
189 if (hw_cpu == xics_default_server)
190 xics_update_irq_servers();
191
192 /* Reject any interrupt that was queued to us... */
193 icp_ops->set_priority(0);
194
195 /* Remove ourselves from the global interrupt queue */
196 xics_set_cpu_giq(xics_default_distrib_server, 0);
197
198 for_each_irq_desc(virq, desc) {
199 struct irq_chip *chip;
200 long server;
201 unsigned long flags;
202 struct irq_data *irqd;
203
204 /* We can't set affinity on ISA interrupts */
205 if (virq < NR_IRQS_LEGACY)
206 continue;
207 /* We only need to migrate enabled IRQS */
208 if (!desc->action)
209 continue;
210 /* We need a mapping in the XICS IRQ domain */
211 irqd = irq_domain_get_irq_data(xics_host, virq);
212 if (!irqd)
213 continue;
214 irq = irqd_to_hwirq(irqd);
215 /* We need to get IPIs still. */
216 if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
217 continue;
218 chip = irq_desc_get_chip(desc);
219 if (!chip || !chip->irq_set_affinity)
220 continue;
221
222 raw_spin_lock_irqsave(&desc->lock, flags);
223
224 /* Locate interrupt server */
225 server = xics_ics->get_server(xics_ics, irq);
226 if (server < 0) {
227 pr_err("%s: Can't find server for irq %d/%x\n",
228 __func__, virq, irq);
229 goto unlock;
230 }
231
232 /* We only support delivery to all cpus or to one cpu.
233 * The irq has to be migrated only in the single cpu
234 * case.
235 */
236 if (server != hw_cpu)
237 goto unlock;
238
239 /* This is expected during cpu offline. */
240 if (cpu_online(cpu))
241 pr_warn("IRQ %u affinity broken off cpu %u\n",
242 virq, cpu);
243
244 /* Reset affinity to all cpus */
245 raw_spin_unlock_irqrestore(&desc->lock, flags);
246 irq_set_affinity(virq, cpu_all_mask);
247 continue;
248unlock:
249 raw_spin_unlock_irqrestore(&desc->lock, flags);
250 }
251
252 /* Allow "sufficient" time to drop any inflight IRQ's */
253 mdelay(5);
254
255 /*
256 * Allow IPIs again. This is done at the very end, after migrating all
257 * interrupts, the expectation is that we'll only get woken up by an IPI
258 * interrupt beyond this point, but leave externals masked just to be
259 * safe. If we're using icp-opal this may actually allow all
260 * interrupts anyway, but that should be OK.
261 */
262 icp_ops->set_priority(DEFAULT_PRIORITY);
263
264}
265#endif /* CONFIG_HOTPLUG_CPU */
266
267#ifdef CONFIG_SMP
268/*
269 * For the moment we only implement delivery to all cpus or one cpu.
270 *
271 * If the requested affinity is cpu_all_mask, we set global affinity.
272 * If not we set it to the first cpu in the mask, even if multiple cpus
273 * are set. This is so things like irqbalance (which set core and package
274 * wide affinities) do the right thing.
275 *
276 * We need to fix this to implement support for the links
277 */
278int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
279 unsigned int strict_check)
280{
281
282 if (!distribute_irqs)
283 return xics_default_server;
284
285 if (!cpumask_subset(cpu_possible_mask, cpumask)) {
286 int server = cpumask_first_and(cpu_online_mask, cpumask);
287
288 if (server < nr_cpu_ids)
289 return get_hard_smp_processor_id(server);
290
291 if (strict_check)
292 return -1;
293 }
294
295 /*
296 * Workaround issue with some versions of JS20 firmware that
297 * deliver interrupts to cpus which haven't been started. This
298 * happens when using the maxcpus= boot option.
299 */
300 if (cpumask_equal(cpu_online_mask, cpu_present_mask))
301 return xics_default_distrib_server;
302
303 return xics_default_server;
304}
305#endif /* CONFIG_SMP */
306
307static int xics_host_match(struct irq_domain *h, struct device_node *node,
308 enum irq_domain_bus_token bus_token)
309{
310 if (WARN_ON(!xics_ics))
311 return 0;
312 return xics_ics->host_match(xics_ics, node) ? 1 : 0;
313}
314
315/* Dummies */
316static void xics_ipi_unmask(struct irq_data *d) { }
317static void xics_ipi_mask(struct irq_data *d) { }
318
319static struct irq_chip xics_ipi_chip = {
320 .name = "XICS",
321 .irq_eoi = NULL, /* Patched at init time */
322 .irq_mask = xics_ipi_mask,
323 .irq_unmask = xics_ipi_unmask,
324};
325
326static int xics_host_map(struct irq_domain *domain, unsigned int virq,
327 irq_hw_number_t hwirq)
328{
329 pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hwirq);
330
331 /*
332 * Mark interrupts as edge sensitive by default so that resend
333 * actually works. The device-tree parsing will turn the LSIs
334 * back to level.
335 */
336 irq_clear_status_flags(virq, IRQ_LEVEL);
337
338 /* Don't call into ICS for IPIs */
339 if (hwirq == XICS_IPI) {
340 irq_set_chip_and_handler(virq, &xics_ipi_chip,
341 handle_percpu_irq);
342 return 0;
343 }
344
345 if (WARN_ON(!xics_ics))
346 return -EINVAL;
347
348 if (xics_ics->check(xics_ics, hwirq))
349 return -EINVAL;
350
351 /* Let the ICS be the chip data for the XICS domain. For ICS native */
352 irq_domain_set_info(domain, virq, hwirq, xics_ics->chip,
353 xics_ics, handle_fasteoi_irq, NULL, NULL);
354
355 return 0;
356}
357
358static int xics_host_xlate(struct irq_domain *h, struct device_node *ct,
359 const u32 *intspec, unsigned int intsize,
360 irq_hw_number_t *out_hwirq, unsigned int *out_flags)
361
362{
363 *out_hwirq = intspec[0];
364
365 /*
366 * If intsize is at least 2, we look for the type in the second cell,
367 * we assume the LSB indicates a level interrupt.
368 */
369 if (intsize > 1) {
370 if (intspec[1] & 1)
371 *out_flags = IRQ_TYPE_LEVEL_LOW;
372 else
373 *out_flags = IRQ_TYPE_EDGE_RISING;
374 } else
375 *out_flags = IRQ_TYPE_LEVEL_LOW;
376
377 return 0;
378}
379
380int xics_set_irq_type(struct irq_data *d, unsigned int flow_type)
381{
382 /*
383 * We only support these. This has really no effect other than setting
384 * the corresponding descriptor bits mind you but those will in turn
385 * affect the resend function when re-enabling an edge interrupt.
386 *
387 * Set set the default to edge as explained in map().
388 */
389 if (flow_type == IRQ_TYPE_DEFAULT || flow_type == IRQ_TYPE_NONE)
390 flow_type = IRQ_TYPE_EDGE_RISING;
391
392 if (flow_type != IRQ_TYPE_EDGE_RISING &&
393 flow_type != IRQ_TYPE_LEVEL_LOW)
394 return -EINVAL;
395
396 irqd_set_trigger_type(d, flow_type);
397
398 return IRQ_SET_MASK_OK_NOCOPY;
399}
400
401int xics_retrigger(struct irq_data *data)
402{
403 /*
404 * We need to push a dummy CPPR when retriggering, since the subsequent
405 * EOI will try to pop it. Passing 0 works, as the function hard codes
406 * the priority value anyway.
407 */
408 xics_push_cppr(0);
409
410 /* Tell the core to do a soft retrigger */
411 return 0;
412}
413
414#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
415static int xics_host_domain_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
416 unsigned long *hwirq, unsigned int *type)
417{
418 return xics_host_xlate(d, to_of_node(fwspec->fwnode), fwspec->param,
419 fwspec->param_count, hwirq, type);
420}
421
422static int xics_host_domain_alloc(struct irq_domain *domain, unsigned int virq,
423 unsigned int nr_irqs, void *arg)
424{
425 struct irq_fwspec *fwspec = arg;
426 irq_hw_number_t hwirq;
427 unsigned int type = IRQ_TYPE_NONE;
428 int i, rc;
429
430 rc = xics_host_domain_translate(domain, fwspec, &hwirq, &type);
431 if (rc)
432 return rc;
433
434 pr_debug("%s %d/%lx #%d\n", __func__, virq, hwirq, nr_irqs);
435
436 for (i = 0; i < nr_irqs; i++)
437 irq_domain_set_info(domain, virq + i, hwirq + i, xics_ics->chip,
438 xics_ics, handle_fasteoi_irq, NULL, NULL);
439
440 return 0;
441}
442
443static void xics_host_domain_free(struct irq_domain *domain,
444 unsigned int virq, unsigned int nr_irqs)
445{
446 pr_debug("%s %d #%d\n", __func__, virq, nr_irqs);
447}
448#endif
449
450static const struct irq_domain_ops xics_host_ops = {
451#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
452 .alloc = xics_host_domain_alloc,
453 .free = xics_host_domain_free,
454 .translate = xics_host_domain_translate,
455#endif
456 .match = xics_host_match,
457 .map = xics_host_map,
458 .xlate = xics_host_xlate,
459};
460
461static int __init xics_allocate_domain(void)
462{
463 struct fwnode_handle *fn;
464
465 fn = irq_domain_alloc_named_fwnode("XICS");
466 if (!fn)
467 return -ENOMEM;
468
469 xics_host = irq_domain_create_tree(fn, &xics_host_ops, NULL);
470 if (!xics_host) {
471 irq_domain_free_fwnode(fn);
472 return -ENOMEM;
473 }
474
475 irq_set_default_host(xics_host);
476 return 0;
477}
478
479void __init xics_register_ics(struct ics *ics)
480{
481 if (WARN_ONCE(xics_ics, "XICS: Source Controller is already defined !"))
482 return;
483 xics_ics = ics;
484}
485
486static void __init xics_get_server_size(void)
487{
488 struct device_node *np;
489 const __be32 *isize;
490
491 /* We fetch the interrupt server size from the first ICS node
492 * we find if any
493 */
494 np = of_find_compatible_node(NULL, NULL, "ibm,ppc-xics");
495 if (!np)
496 return;
497
498 isize = of_get_property(np, "ibm,interrupt-server#-size", NULL);
499 if (isize)
500 xics_interrupt_server_size = be32_to_cpu(*isize);
501
502 of_node_put(np);
503}
504
505void __init xics_init(void)
506{
507 int rc = -1;
508
509 /* Fist locate ICP */
510 if (firmware_has_feature(FW_FEATURE_LPAR))
511 rc = icp_hv_init();
512 if (rc < 0) {
513 rc = icp_native_init();
514 if (rc == -ENODEV)
515 rc = icp_opal_init();
516 }
517 if (rc < 0) {
518 pr_warn("XICS: Cannot find a Presentation Controller !\n");
519 return;
520 }
521
522 /* Copy get_irq callback over to ppc_md */
523 ppc_md.get_irq = icp_ops->get_irq;
524
525 /* Patch up IPI chip EOI */
526 xics_ipi_chip.irq_eoi = icp_ops->eoi;
527
528 /* Now locate ICS */
529 rc = ics_rtas_init();
530 if (rc < 0)
531 rc = ics_opal_init();
532 if (rc < 0)
533 rc = ics_native_init();
534 if (rc < 0)
535 pr_warn("XICS: Cannot find a Source Controller !\n");
536
537 /* Initialize common bits */
538 xics_get_server_size();
539 xics_update_irq_servers();
540 rc = xics_allocate_domain();
541 if (rc < 0)
542 pr_err("XICS: Failed to create IRQ domain");
543 xics_setup_cpu();
544}
1/*
2 * Copyright 2011 IBM Corporation.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 */
10#include <linux/types.h>
11#include <linux/threads.h>
12#include <linux/kernel.h>
13#include <linux/irq.h>
14#include <linux/debugfs.h>
15#include <linux/smp.h>
16#include <linux/interrupt.h>
17#include <linux/seq_file.h>
18#include <linux/init.h>
19#include <linux/cpu.h>
20#include <linux/of.h>
21#include <linux/slab.h>
22#include <linux/spinlock.h>
23#include <linux/delay.h>
24
25#include <asm/prom.h>
26#include <asm/io.h>
27#include <asm/smp.h>
28#include <asm/machdep.h>
29#include <asm/irq.h>
30#include <asm/errno.h>
31#include <asm/rtas.h>
32#include <asm/xics.h>
33#include <asm/firmware.h>
34
35/* Globals common to all ICP/ICS implementations */
36const struct icp_ops *icp_ops;
37
38unsigned int xics_default_server = 0xff;
39unsigned int xics_default_distrib_server = 0;
40unsigned int xics_interrupt_server_size = 8;
41
42DEFINE_PER_CPU(struct xics_cppr, xics_cppr);
43
44struct irq_domain *xics_host;
45
46static LIST_HEAD(ics_list);
47
48void xics_update_irq_servers(void)
49{
50 int i, j;
51 struct device_node *np;
52 u32 ilen;
53 const __be32 *ireg;
54 u32 hcpuid;
55
56 /* Find the server numbers for the boot cpu. */
57 np = of_get_cpu_node(boot_cpuid, NULL);
58 BUG_ON(!np);
59
60 hcpuid = get_hard_smp_processor_id(boot_cpuid);
61 xics_default_server = xics_default_distrib_server = hcpuid;
62
63 pr_devel("xics: xics_default_server = 0x%x\n", xics_default_server);
64
65 ireg = of_get_property(np, "ibm,ppc-interrupt-gserver#s", &ilen);
66 if (!ireg) {
67 of_node_put(np);
68 return;
69 }
70
71 i = ilen / sizeof(int);
72
73 /* Global interrupt distribution server is specified in the last
74 * entry of "ibm,ppc-interrupt-gserver#s" property. Get the last
75 * entry fom this property for current boot cpu id and use it as
76 * default distribution server
77 */
78 for (j = 0; j < i; j += 2) {
79 if (be32_to_cpu(ireg[j]) == hcpuid) {
80 xics_default_distrib_server = be32_to_cpu(ireg[j+1]);
81 break;
82 }
83 }
84 pr_devel("xics: xics_default_distrib_server = 0x%x\n",
85 xics_default_distrib_server);
86 of_node_put(np);
87}
88
89/* GIQ stuff, currently only supported on RTAS setups, will have
90 * to be sorted properly for bare metal
91 */
92void xics_set_cpu_giq(unsigned int gserver, unsigned int join)
93{
94#ifdef CONFIG_PPC_RTAS
95 int index;
96 int status;
97
98 if (!rtas_indicator_present(GLOBAL_INTERRUPT_QUEUE, NULL))
99 return;
100
101 index = (1UL << xics_interrupt_server_size) - 1 - gserver;
102
103 status = rtas_set_indicator_fast(GLOBAL_INTERRUPT_QUEUE, index, join);
104
105 WARN(status < 0, "set-indicator(%d, %d, %u) returned %d\n",
106 GLOBAL_INTERRUPT_QUEUE, index, join, status);
107#endif
108}
109
110void xics_setup_cpu(void)
111{
112 icp_ops->set_priority(LOWEST_PRIORITY);
113
114 xics_set_cpu_giq(xics_default_distrib_server, 1);
115}
116
117void xics_mask_unknown_vec(unsigned int vec)
118{
119 struct ics *ics;
120
121 pr_err("Interrupt 0x%x (real) is invalid, disabling it.\n", vec);
122
123 list_for_each_entry(ics, &ics_list, link)
124 ics->mask_unknown(ics, vec);
125}
126
127
128#ifdef CONFIG_SMP
129
130static void xics_request_ipi(void)
131{
132 unsigned int ipi;
133
134 ipi = irq_create_mapping(xics_host, XICS_IPI);
135 BUG_ON(!ipi);
136
137 /*
138 * IPIs are marked IRQF_PERCPU. The handler was set in map.
139 */
140 BUG_ON(request_irq(ipi, icp_ops->ipi_action,
141 IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL));
142}
143
144void __init xics_smp_probe(void)
145{
146 /* Register all the IPIs */
147 xics_request_ipi();
148
149 /* Setup cause_ipi callback based on which ICP is used */
150 smp_ops->cause_ipi = icp_ops->cause_ipi;
151}
152
153#endif /* CONFIG_SMP */
154
155void xics_teardown_cpu(void)
156{
157 struct xics_cppr *os_cppr = this_cpu_ptr(&xics_cppr);
158
159 /*
160 * we have to reset the cppr index to 0 because we're
161 * not going to return from the IPI
162 */
163 os_cppr->index = 0;
164 icp_ops->set_priority(0);
165 icp_ops->teardown_cpu();
166}
167
168void xics_kexec_teardown_cpu(int secondary)
169{
170 xics_teardown_cpu();
171
172 icp_ops->flush_ipi();
173
174 /*
175 * Some machines need to have at least one cpu in the GIQ,
176 * so leave the master cpu in the group.
177 */
178 if (secondary)
179 xics_set_cpu_giq(xics_default_distrib_server, 0);
180}
181
182
183#ifdef CONFIG_HOTPLUG_CPU
184
185/* Interrupts are disabled. */
186void xics_migrate_irqs_away(void)
187{
188 int cpu = smp_processor_id(), hw_cpu = hard_smp_processor_id();
189 unsigned int irq, virq;
190 struct irq_desc *desc;
191
192 /* If we used to be the default server, move to the new "boot_cpuid" */
193 if (hw_cpu == xics_default_server)
194 xics_update_irq_servers();
195
196 /* Reject any interrupt that was queued to us... */
197 icp_ops->set_priority(0);
198
199 /* Remove ourselves from the global interrupt queue */
200 xics_set_cpu_giq(xics_default_distrib_server, 0);
201
202 for_each_irq_desc(virq, desc) {
203 struct irq_chip *chip;
204 long server;
205 unsigned long flags;
206 struct ics *ics;
207
208 /* We can't set affinity on ISA interrupts */
209 if (virq < NUM_ISA_INTERRUPTS)
210 continue;
211 /* We only need to migrate enabled IRQS */
212 if (!desc->action)
213 continue;
214 if (desc->irq_data.domain != xics_host)
215 continue;
216 irq = desc->irq_data.hwirq;
217 /* We need to get IPIs still. */
218 if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
219 continue;
220 chip = irq_desc_get_chip(desc);
221 if (!chip || !chip->irq_set_affinity)
222 continue;
223
224 raw_spin_lock_irqsave(&desc->lock, flags);
225
226 /* Locate interrupt server */
227 server = -1;
228 ics = irq_desc_get_chip_data(desc);
229 if (ics)
230 server = ics->get_server(ics, irq);
231 if (server < 0) {
232 printk(KERN_ERR "%s: Can't find server for irq %d\n",
233 __func__, irq);
234 goto unlock;
235 }
236
237 /* We only support delivery to all cpus or to one cpu.
238 * The irq has to be migrated only in the single cpu
239 * case.
240 */
241 if (server != hw_cpu)
242 goto unlock;
243
244 /* This is expected during cpu offline. */
245 if (cpu_online(cpu))
246 pr_warn("IRQ %u affinity broken off cpu %u\n",
247 virq, cpu);
248
249 /* Reset affinity to all cpus */
250 raw_spin_unlock_irqrestore(&desc->lock, flags);
251 irq_set_affinity(virq, cpu_all_mask);
252 continue;
253unlock:
254 raw_spin_unlock_irqrestore(&desc->lock, flags);
255 }
256
257 /* Allow "sufficient" time to drop any inflight IRQ's */
258 mdelay(5);
259
260 /*
261 * Allow IPIs again. This is done at the very end, after migrating all
262 * interrupts, the expectation is that we'll only get woken up by an IPI
263 * interrupt beyond this point, but leave externals masked just to be
264 * safe. If we're using icp-opal this may actually allow all
265 * interrupts anyway, but that should be OK.
266 */
267 icp_ops->set_priority(DEFAULT_PRIORITY);
268
269}
270#endif /* CONFIG_HOTPLUG_CPU */
271
272#ifdef CONFIG_SMP
273/*
274 * For the moment we only implement delivery to all cpus or one cpu.
275 *
276 * If the requested affinity is cpu_all_mask, we set global affinity.
277 * If not we set it to the first cpu in the mask, even if multiple cpus
278 * are set. This is so things like irqbalance (which set core and package
279 * wide affinities) do the right thing.
280 *
281 * We need to fix this to implement support for the links
282 */
283int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
284 unsigned int strict_check)
285{
286
287 if (!distribute_irqs)
288 return xics_default_server;
289
290 if (!cpumask_subset(cpu_possible_mask, cpumask)) {
291 int server = cpumask_first_and(cpu_online_mask, cpumask);
292
293 if (server < nr_cpu_ids)
294 return get_hard_smp_processor_id(server);
295
296 if (strict_check)
297 return -1;
298 }
299
300 /*
301 * Workaround issue with some versions of JS20 firmware that
302 * deliver interrupts to cpus which haven't been started. This
303 * happens when using the maxcpus= boot option.
304 */
305 if (cpumask_equal(cpu_online_mask, cpu_present_mask))
306 return xics_default_distrib_server;
307
308 return xics_default_server;
309}
310#endif /* CONFIG_SMP */
311
312static int xics_host_match(struct irq_domain *h, struct device_node *node,
313 enum irq_domain_bus_token bus_token)
314{
315 struct ics *ics;
316
317 list_for_each_entry(ics, &ics_list, link)
318 if (ics->host_match(ics, node))
319 return 1;
320
321 return 0;
322}
323
324/* Dummies */
325static void xics_ipi_unmask(struct irq_data *d) { }
326static void xics_ipi_mask(struct irq_data *d) { }
327
328static struct irq_chip xics_ipi_chip = {
329 .name = "XICS",
330 .irq_eoi = NULL, /* Patched at init time */
331 .irq_mask = xics_ipi_mask,
332 .irq_unmask = xics_ipi_unmask,
333};
334
335static int xics_host_map(struct irq_domain *h, unsigned int virq,
336 irq_hw_number_t hw)
337{
338 struct ics *ics;
339
340 pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hw);
341
342 /*
343 * Mark interrupts as edge sensitive by default so that resend
344 * actually works. The device-tree parsing will turn the LSIs
345 * back to level.
346 */
347 irq_clear_status_flags(virq, IRQ_LEVEL);
348
349 /* Don't call into ICS for IPIs */
350 if (hw == XICS_IPI) {
351 irq_set_chip_and_handler(virq, &xics_ipi_chip,
352 handle_percpu_irq);
353 return 0;
354 }
355
356 /* Let the ICS setup the chip data */
357 list_for_each_entry(ics, &ics_list, link)
358 if (ics->map(ics, virq) == 0)
359 return 0;
360
361 return -EINVAL;
362}
363
364static int xics_host_xlate(struct irq_domain *h, struct device_node *ct,
365 const u32 *intspec, unsigned int intsize,
366 irq_hw_number_t *out_hwirq, unsigned int *out_flags)
367
368{
369 *out_hwirq = intspec[0];
370
371 /*
372 * If intsize is at least 2, we look for the type in the second cell,
373 * we assume the LSB indicates a level interrupt.
374 */
375 if (intsize > 1) {
376 if (intspec[1] & 1)
377 *out_flags = IRQ_TYPE_LEVEL_LOW;
378 else
379 *out_flags = IRQ_TYPE_EDGE_RISING;
380 } else
381 *out_flags = IRQ_TYPE_LEVEL_LOW;
382
383 return 0;
384}
385
386int xics_set_irq_type(struct irq_data *d, unsigned int flow_type)
387{
388 /*
389 * We only support these. This has really no effect other than setting
390 * the corresponding descriptor bits mind you but those will in turn
391 * affect the resend function when re-enabling an edge interrupt.
392 *
393 * Set set the default to edge as explained in map().
394 */
395 if (flow_type == IRQ_TYPE_DEFAULT || flow_type == IRQ_TYPE_NONE)
396 flow_type = IRQ_TYPE_EDGE_RISING;
397
398 if (flow_type != IRQ_TYPE_EDGE_RISING &&
399 flow_type != IRQ_TYPE_LEVEL_LOW)
400 return -EINVAL;
401
402 irqd_set_trigger_type(d, flow_type);
403
404 return IRQ_SET_MASK_OK_NOCOPY;
405}
406
407int xics_retrigger(struct irq_data *data)
408{
409 /*
410 * We need to push a dummy CPPR when retriggering, since the subsequent
411 * EOI will try to pop it. Passing 0 works, as the function hard codes
412 * the priority value anyway.
413 */
414 xics_push_cppr(0);
415
416 /* Tell the core to do a soft retrigger */
417 return 0;
418}
419
420static const struct irq_domain_ops xics_host_ops = {
421 .match = xics_host_match,
422 .map = xics_host_map,
423 .xlate = xics_host_xlate,
424};
425
426static void __init xics_init_host(void)
427{
428 xics_host = irq_domain_add_tree(NULL, &xics_host_ops, NULL);
429 BUG_ON(xics_host == NULL);
430 irq_set_default_host(xics_host);
431}
432
433void __init xics_register_ics(struct ics *ics)
434{
435 list_add(&ics->link, &ics_list);
436}
437
438static void __init xics_get_server_size(void)
439{
440 struct device_node *np;
441 const __be32 *isize;
442
443 /* We fetch the interrupt server size from the first ICS node
444 * we find if any
445 */
446 np = of_find_compatible_node(NULL, NULL, "ibm,ppc-xics");
447 if (!np)
448 return;
449 isize = of_get_property(np, "ibm,interrupt-server#-size", NULL);
450 if (!isize)
451 return;
452 xics_interrupt_server_size = be32_to_cpu(*isize);
453 of_node_put(np);
454}
455
456void __init xics_init(void)
457{
458 int rc = -1;
459
460 /* Fist locate ICP */
461 if (firmware_has_feature(FW_FEATURE_LPAR))
462 rc = icp_hv_init();
463 if (rc < 0) {
464 rc = icp_native_init();
465 if (rc == -ENODEV)
466 rc = icp_opal_init();
467 }
468 if (rc < 0) {
469 pr_warn("XICS: Cannot find a Presentation Controller !\n");
470 return;
471 }
472
473 /* Copy get_irq callback over to ppc_md */
474 ppc_md.get_irq = icp_ops->get_irq;
475
476 /* Patch up IPI chip EOI */
477 xics_ipi_chip.irq_eoi = icp_ops->eoi;
478
479 /* Now locate ICS */
480 rc = ics_rtas_init();
481 if (rc < 0)
482 rc = ics_opal_init();
483 if (rc < 0)
484 pr_warn("XICS: Cannot find a Source Controller !\n");
485
486 /* Initialize common bits */
487 xics_get_server_size();
488 xics_update_irq_servers();
489 xics_init_host();
490 xics_setup_cpu();
491}