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1/*
2 * Copyright IBM Corp. 2004,2011
3 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
4 * Holger Smolinski <Holger.Smolinski@de.ibm.com>,
5 * Thomas Spatzier <tspat@de.ibm.com>,
6 *
7 * This file contains interrupt related functions.
8 */
9
10#include <linux/kernel_stat.h>
11#include <linux/interrupt.h>
12#include <linux/seq_file.h>
13#include <linux/proc_fs.h>
14#include <linux/profile.h>
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/ftrace.h>
18#include <linux/errno.h>
19#include <linux/slab.h>
20#include <linux/cpu.h>
21#include <asm/irq_regs.h>
22#include <asm/cputime.h>
23#include <asm/lowcore.h>
24#include <asm/irq.h>
25#include "entry.h"
26
27struct irq_class {
28 char *name;
29 char *desc;
30};
31
32static const struct irq_class intrclass_names[] = {
33 {.name = "EXT" },
34 {.name = "I/O" },
35 {.name = "CLK", .desc = "[EXT] Clock Comparator" },
36 {.name = "IPI", .desc = "[EXT] Signal Processor" },
37 {.name = "TMR", .desc = "[EXT] CPU Timer" },
38 {.name = "TAL", .desc = "[EXT] Timing Alert" },
39 {.name = "PFL", .desc = "[EXT] Pseudo Page Fault" },
40 {.name = "DSD", .desc = "[EXT] DASD Diag" },
41 {.name = "VRT", .desc = "[EXT] Virtio" },
42 {.name = "SCP", .desc = "[EXT] Service Call" },
43 {.name = "IUC", .desc = "[EXT] IUCV" },
44 {.name = "CPM", .desc = "[EXT] CPU Measurement" },
45 {.name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt" },
46 {.name = "QDI", .desc = "[I/O] QDIO Interrupt" },
47 {.name = "DAS", .desc = "[I/O] DASD" },
48 {.name = "C15", .desc = "[I/O] 3215" },
49 {.name = "C70", .desc = "[I/O] 3270" },
50 {.name = "TAP", .desc = "[I/O] Tape" },
51 {.name = "VMR", .desc = "[I/O] Unit Record Devices" },
52 {.name = "LCS", .desc = "[I/O] LCS" },
53 {.name = "CLW", .desc = "[I/O] CLAW" },
54 {.name = "CTC", .desc = "[I/O] CTC" },
55 {.name = "APB", .desc = "[I/O] AP Bus" },
56 {.name = "NMI", .desc = "[NMI] Machine Check" },
57};
58
59/*
60 * show_interrupts is needed by /proc/interrupts.
61 */
62int show_interrupts(struct seq_file *p, void *v)
63{
64 int i = *(loff_t *) v, j;
65
66 get_online_cpus();
67 if (i == 0) {
68 seq_puts(p, " ");
69 for_each_online_cpu(j)
70 seq_printf(p, "CPU%d ",j);
71 seq_putc(p, '\n');
72 }
73
74 if (i < NR_IRQS) {
75 seq_printf(p, "%s: ", intrclass_names[i].name);
76#ifndef CONFIG_SMP
77 seq_printf(p, "%10u ", kstat_irqs(i));
78#else
79 for_each_online_cpu(j)
80 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
81#endif
82 if (intrclass_names[i].desc)
83 seq_printf(p, " %s", intrclass_names[i].desc);
84 seq_putc(p, '\n');
85 }
86 put_online_cpus();
87 return 0;
88}
89
90/*
91 * Switch to the asynchronous interrupt stack for softirq execution.
92 */
93asmlinkage void do_softirq(void)
94{
95 unsigned long flags, old, new;
96
97 if (in_interrupt())
98 return;
99
100 local_irq_save(flags);
101
102 if (local_softirq_pending()) {
103 /* Get current stack pointer. */
104 asm volatile("la %0,0(15)" : "=a" (old));
105 /* Check against async. stack address range. */
106 new = S390_lowcore.async_stack;
107 if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
108 /* Need to switch to the async. stack. */
109 new -= STACK_FRAME_OVERHEAD;
110 ((struct stack_frame *) new)->back_chain = old;
111
112 asm volatile(" la 15,0(%0)\n"
113 " basr 14,%2\n"
114 " la 15,0(%1)\n"
115 : : "a" (new), "a" (old),
116 "a" (__do_softirq)
117 : "0", "1", "2", "3", "4", "5", "14",
118 "cc", "memory" );
119 } else
120 /* We are already on the async stack. */
121 __do_softirq();
122 }
123
124 local_irq_restore(flags);
125}
126
127#ifdef CONFIG_PROC_FS
128void init_irq_proc(void)
129{
130 struct proc_dir_entry *root_irq_dir;
131
132 root_irq_dir = proc_mkdir("irq", NULL);
133 create_prof_cpu_mask(root_irq_dir);
134}
135#endif
136
137/*
138 * ext_int_hash[index] is the list head for all external interrupts that hash
139 * to this index.
140 */
141static struct list_head ext_int_hash[256];
142
143struct ext_int_info {
144 ext_int_handler_t handler;
145 u16 code;
146 struct list_head entry;
147 struct rcu_head rcu;
148};
149
150/* ext_int_hash_lock protects the handler lists for external interrupts */
151DEFINE_SPINLOCK(ext_int_hash_lock);
152
153static void __init init_external_interrupts(void)
154{
155 int idx;
156
157 for (idx = 0; idx < ARRAY_SIZE(ext_int_hash); idx++)
158 INIT_LIST_HEAD(&ext_int_hash[idx]);
159}
160
161static inline int ext_hash(u16 code)
162{
163 return (code + (code >> 9)) & 0xff;
164}
165
166static void ext_int_hash_update(struct rcu_head *head)
167{
168 struct ext_int_info *p = container_of(head, struct ext_int_info, rcu);
169
170 kfree(p);
171}
172
173int register_external_interrupt(u16 code, ext_int_handler_t handler)
174{
175 struct ext_int_info *p;
176 unsigned long flags;
177 int index;
178
179 p = kmalloc(sizeof(*p), GFP_ATOMIC);
180 if (!p)
181 return -ENOMEM;
182 p->code = code;
183 p->handler = handler;
184 index = ext_hash(code);
185
186 spin_lock_irqsave(&ext_int_hash_lock, flags);
187 list_add_rcu(&p->entry, &ext_int_hash[index]);
188 spin_unlock_irqrestore(&ext_int_hash_lock, flags);
189 return 0;
190}
191EXPORT_SYMBOL(register_external_interrupt);
192
193int unregister_external_interrupt(u16 code, ext_int_handler_t handler)
194{
195 struct ext_int_info *p;
196 unsigned long flags;
197 int index = ext_hash(code);
198
199 spin_lock_irqsave(&ext_int_hash_lock, flags);
200 list_for_each_entry_rcu(p, &ext_int_hash[index], entry)
201 if (p->code == code && p->handler == handler) {
202 list_del_rcu(&p->entry);
203 call_rcu(&p->rcu, ext_int_hash_update);
204 }
205 spin_unlock_irqrestore(&ext_int_hash_lock, flags);
206 return 0;
207}
208EXPORT_SYMBOL(unregister_external_interrupt);
209
210void __irq_entry do_extint(struct pt_regs *regs, unsigned int ext_int_code,
211 unsigned int param32, unsigned long param64)
212{
213 struct pt_regs *old_regs;
214 unsigned short code;
215 struct ext_int_info *p;
216 int index;
217
218 code = (unsigned short) ext_int_code;
219 old_regs = set_irq_regs(regs);
220 s390_idle_check(regs, S390_lowcore.int_clock,
221 S390_lowcore.async_enter_timer);
222 irq_enter();
223 if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator)
224 /* Serve timer interrupts first. */
225 clock_comparator_work();
226 kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++;
227 if (code != 0x1004)
228 __get_cpu_var(s390_idle).nohz_delay = 1;
229
230 index = ext_hash(code);
231 rcu_read_lock();
232 list_for_each_entry_rcu(p, &ext_int_hash[index], entry)
233 if (likely(p->code == code))
234 p->handler(ext_int_code, param32, param64);
235 rcu_read_unlock();
236 irq_exit();
237 set_irq_regs(old_regs);
238}
239
240void __init init_IRQ(void)
241{
242 init_external_interrupts();
243}
244
245static DEFINE_SPINLOCK(sc_irq_lock);
246static int sc_irq_refcount;
247
248void service_subclass_irq_register(void)
249{
250 spin_lock(&sc_irq_lock);
251 if (!sc_irq_refcount)
252 ctl_set_bit(0, 9);
253 sc_irq_refcount++;
254 spin_unlock(&sc_irq_lock);
255}
256EXPORT_SYMBOL(service_subclass_irq_register);
257
258void service_subclass_irq_unregister(void)
259{
260 spin_lock(&sc_irq_lock);
261 sc_irq_refcount--;
262 if (!sc_irq_refcount)
263 ctl_clear_bit(0, 9);
264 spin_unlock(&sc_irq_lock);
265}
266EXPORT_SYMBOL(service_subclass_irq_unregister);
1/*
2 * Copyright IBM Corp. 2004,2011
3 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
4 * Holger Smolinski <Holger.Smolinski@de.ibm.com>,
5 * Thomas Spatzier <tspat@de.ibm.com>,
6 *
7 * This file contains interrupt related functions.
8 */
9
10#include <linux/kernel_stat.h>
11#include <linux/interrupt.h>
12#include <linux/seq_file.h>
13#include <linux/proc_fs.h>
14#include <linux/profile.h>
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/ftrace.h>
18#include <linux/errno.h>
19#include <linux/slab.h>
20#include <linux/cpu.h>
21#include <asm/irq_regs.h>
22#include <asm/cputime.h>
23#include <asm/lowcore.h>
24#include <asm/irq.h>
25#include "entry.h"
26
27struct irq_class {
28 char *name;
29 char *desc;
30};
31
32static const struct irq_class intrclass_names[] = {
33 {.name = "EXT" },
34 {.name = "I/O" },
35 {.name = "CLK", .desc = "[EXT] Clock Comparator" },
36 {.name = "EXC", .desc = "[EXT] External Call" },
37 {.name = "EMS", .desc = "[EXT] Emergency Signal" },
38 {.name = "TMR", .desc = "[EXT] CPU Timer" },
39 {.name = "TAL", .desc = "[EXT] Timing Alert" },
40 {.name = "PFL", .desc = "[EXT] Pseudo Page Fault" },
41 {.name = "DSD", .desc = "[EXT] DASD Diag" },
42 {.name = "VRT", .desc = "[EXT] Virtio" },
43 {.name = "SCP", .desc = "[EXT] Service Call" },
44 {.name = "IUC", .desc = "[EXT] IUCV" },
45 {.name = "CMS", .desc = "[EXT] CPU-Measurement: Sampling" },
46 {.name = "CMC", .desc = "[EXT] CPU-Measurement: Counter" },
47 {.name = "CIO", .desc = "[I/O] Common I/O Layer Interrupt" },
48 {.name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt" },
49 {.name = "DAS", .desc = "[I/O] DASD" },
50 {.name = "C15", .desc = "[I/O] 3215" },
51 {.name = "C70", .desc = "[I/O] 3270" },
52 {.name = "TAP", .desc = "[I/O] Tape" },
53 {.name = "VMR", .desc = "[I/O] Unit Record Devices" },
54 {.name = "LCS", .desc = "[I/O] LCS" },
55 {.name = "CLW", .desc = "[I/O] CLAW" },
56 {.name = "CTC", .desc = "[I/O] CTC" },
57 {.name = "APB", .desc = "[I/O] AP Bus" },
58 {.name = "CSC", .desc = "[I/O] CHSC Subchannel" },
59 {.name = "NMI", .desc = "[NMI] Machine Check" },
60};
61
62/*
63 * show_interrupts is needed by /proc/interrupts.
64 */
65int show_interrupts(struct seq_file *p, void *v)
66{
67 int i = *(loff_t *) v, j;
68
69 get_online_cpus();
70 if (i == 0) {
71 seq_puts(p, " ");
72 for_each_online_cpu(j)
73 seq_printf(p, "CPU%d ",j);
74 seq_putc(p, '\n');
75 }
76
77 if (i < NR_IRQS) {
78 seq_printf(p, "%s: ", intrclass_names[i].name);
79#ifndef CONFIG_SMP
80 seq_printf(p, "%10u ", kstat_irqs(i));
81#else
82 for_each_online_cpu(j)
83 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
84#endif
85 if (intrclass_names[i].desc)
86 seq_printf(p, " %s", intrclass_names[i].desc);
87 seq_putc(p, '\n');
88 }
89 put_online_cpus();
90 return 0;
91}
92
93/*
94 * Switch to the asynchronous interrupt stack for softirq execution.
95 */
96asmlinkage void do_softirq(void)
97{
98 unsigned long flags, old, new;
99
100 if (in_interrupt())
101 return;
102
103 local_irq_save(flags);
104
105 if (local_softirq_pending()) {
106 /* Get current stack pointer. */
107 asm volatile("la %0,0(15)" : "=a" (old));
108 /* Check against async. stack address range. */
109 new = S390_lowcore.async_stack;
110 if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
111 /* Need to switch to the async. stack. */
112 new -= STACK_FRAME_OVERHEAD;
113 ((struct stack_frame *) new)->back_chain = old;
114
115 asm volatile(" la 15,0(%0)\n"
116 " basr 14,%2\n"
117 " la 15,0(%1)\n"
118 : : "a" (new), "a" (old),
119 "a" (__do_softirq)
120 : "0", "1", "2", "3", "4", "5", "14",
121 "cc", "memory" );
122 } else {
123 /* We are already on the async stack. */
124 __do_softirq();
125 }
126 }
127
128 local_irq_restore(flags);
129}
130
131#ifdef CONFIG_PROC_FS
132void init_irq_proc(void)
133{
134 struct proc_dir_entry *root_irq_dir;
135
136 root_irq_dir = proc_mkdir("irq", NULL);
137 create_prof_cpu_mask(root_irq_dir);
138}
139#endif
140
141/*
142 * ext_int_hash[index] is the list head for all external interrupts that hash
143 * to this index.
144 */
145static struct list_head ext_int_hash[256];
146
147struct ext_int_info {
148 ext_int_handler_t handler;
149 u16 code;
150 struct list_head entry;
151 struct rcu_head rcu;
152};
153
154/* ext_int_hash_lock protects the handler lists for external interrupts */
155DEFINE_SPINLOCK(ext_int_hash_lock);
156
157static void __init init_external_interrupts(void)
158{
159 int idx;
160
161 for (idx = 0; idx < ARRAY_SIZE(ext_int_hash); idx++)
162 INIT_LIST_HEAD(&ext_int_hash[idx]);
163}
164
165static inline int ext_hash(u16 code)
166{
167 return (code + (code >> 9)) & 0xff;
168}
169
170int register_external_interrupt(u16 code, ext_int_handler_t handler)
171{
172 struct ext_int_info *p;
173 unsigned long flags;
174 int index;
175
176 p = kmalloc(sizeof(*p), GFP_ATOMIC);
177 if (!p)
178 return -ENOMEM;
179 p->code = code;
180 p->handler = handler;
181 index = ext_hash(code);
182
183 spin_lock_irqsave(&ext_int_hash_lock, flags);
184 list_add_rcu(&p->entry, &ext_int_hash[index]);
185 spin_unlock_irqrestore(&ext_int_hash_lock, flags);
186 return 0;
187}
188EXPORT_SYMBOL(register_external_interrupt);
189
190int unregister_external_interrupt(u16 code, ext_int_handler_t handler)
191{
192 struct ext_int_info *p;
193 unsigned long flags;
194 int index = ext_hash(code);
195
196 spin_lock_irqsave(&ext_int_hash_lock, flags);
197 list_for_each_entry_rcu(p, &ext_int_hash[index], entry) {
198 if (p->code == code && p->handler == handler) {
199 list_del_rcu(&p->entry);
200 kfree_rcu(p, rcu);
201 }
202 }
203 spin_unlock_irqrestore(&ext_int_hash_lock, flags);
204 return 0;
205}
206EXPORT_SYMBOL(unregister_external_interrupt);
207
208void __irq_entry do_extint(struct pt_regs *regs, struct ext_code ext_code,
209 unsigned int param32, unsigned long param64)
210{
211 struct pt_regs *old_regs;
212 struct ext_int_info *p;
213 int index;
214
215 old_regs = set_irq_regs(regs);
216 irq_enter();
217 if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator) {
218 /* Serve timer interrupts first. */
219 clock_comparator_work();
220 }
221 kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++;
222 if (ext_code.code != 0x1004)
223 __get_cpu_var(s390_idle).nohz_delay = 1;
224
225 index = ext_hash(ext_code.code);
226 rcu_read_lock();
227 list_for_each_entry_rcu(p, &ext_int_hash[index], entry)
228 if (likely(p->code == ext_code.code))
229 p->handler(ext_code, param32, param64);
230 rcu_read_unlock();
231 irq_exit();
232 set_irq_regs(old_regs);
233}
234
235void __init init_IRQ(void)
236{
237 init_external_interrupts();
238}
239
240static DEFINE_SPINLOCK(sc_irq_lock);
241static int sc_irq_refcount;
242
243void service_subclass_irq_register(void)
244{
245 spin_lock(&sc_irq_lock);
246 if (!sc_irq_refcount)
247 ctl_set_bit(0, 9);
248 sc_irq_refcount++;
249 spin_unlock(&sc_irq_lock);
250}
251EXPORT_SYMBOL(service_subclass_irq_register);
252
253void service_subclass_irq_unregister(void)
254{
255 spin_lock(&sc_irq_lock);
256 sc_irq_refcount--;
257 if (!sc_irq_refcount)
258 ctl_clear_bit(0, 9);
259 spin_unlock(&sc_irq_lock);
260}
261EXPORT_SYMBOL(service_subclass_irq_unregister);
262
263static DEFINE_SPINLOCK(ma_subclass_lock);
264static int ma_subclass_refcount;
265
266void measurement_alert_subclass_register(void)
267{
268 spin_lock(&ma_subclass_lock);
269 if (!ma_subclass_refcount)
270 ctl_set_bit(0, 5);
271 ma_subclass_refcount++;
272 spin_unlock(&ma_subclass_lock);
273}
274EXPORT_SYMBOL(measurement_alert_subclass_register);
275
276void measurement_alert_subclass_unregister(void)
277{
278 spin_lock(&ma_subclass_lock);
279 ma_subclass_refcount--;
280 if (!ma_subclass_refcount)
281 ctl_clear_bit(0, 5);
282 spin_unlock(&ma_subclass_lock);
283}
284EXPORT_SYMBOL(measurement_alert_subclass_unregister);