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>,
7 * This file contains interrupt related functions.
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>
27 DEFINE_PER_CPU_SHARED_ALIGNED(struct irq_stat, irq_stat);
28 EXPORT_PER_CPU_SYMBOL_GPL(irq_stat);
36 * The list of "main" irq classes on s390. This is the list of interrrupts
37 * that appear both in /proc/stat ("intr" line) and /proc/interrupts.
38 * Historically only external and I/O interrupts have been part of /proc/stat.
39 * We can't add the split external and I/O sub classes since the first field
40 * in the "intr" line in /proc/stat is supposed to be the sum of all other
42 * Since the external and I/O interrupt fields are already sums we would end
43 * up with having a sum which accounts each interrupt twice.
45 static const struct irq_class irqclass_main_desc[NR_IRQS] = {
46 [EXTERNAL_INTERRUPT] = {.name = "EXT"},
47 [IO_INTERRUPT] = {.name = "I/O"}
51 * The list of split external and I/O interrupts that appear only in
53 * In addition this list contains non external / I/O events like NMIs.
55 static const struct irq_class irqclass_sub_desc[NR_ARCH_IRQS] = {
56 [IRQEXT_CLK] = {.name = "CLK", .desc = "[EXT] Clock Comparator"},
57 [IRQEXT_EXC] = {.name = "EXC", .desc = "[EXT] External Call"},
58 [IRQEXT_EMS] = {.name = "EMS", .desc = "[EXT] Emergency Signal"},
59 [IRQEXT_TMR] = {.name = "TMR", .desc = "[EXT] CPU Timer"},
60 [IRQEXT_TLA] = {.name = "TAL", .desc = "[EXT] Timing Alert"},
61 [IRQEXT_PFL] = {.name = "PFL", .desc = "[EXT] Pseudo Page Fault"},
62 [IRQEXT_DSD] = {.name = "DSD", .desc = "[EXT] DASD Diag"},
63 [IRQEXT_VRT] = {.name = "VRT", .desc = "[EXT] Virtio"},
64 [IRQEXT_SCP] = {.name = "SCP", .desc = "[EXT] Service Call"},
65 [IRQEXT_IUC] = {.name = "IUC", .desc = "[EXT] IUCV"},
66 [IRQEXT_CMS] = {.name = "CMS", .desc = "[EXT] CPU-Measurement: Sampling"},
67 [IRQEXT_CMC] = {.name = "CMC", .desc = "[EXT] CPU-Measurement: Counter"},
68 [IRQEXT_CMR] = {.name = "CMR", .desc = "[EXT] CPU-Measurement: RI"},
69 [IRQIO_CIO] = {.name = "CIO", .desc = "[I/O] Common I/O Layer Interrupt"},
70 [IRQIO_QAI] = {.name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt"},
71 [IRQIO_DAS] = {.name = "DAS", .desc = "[I/O] DASD"},
72 [IRQIO_C15] = {.name = "C15", .desc = "[I/O] 3215"},
73 [IRQIO_C70] = {.name = "C70", .desc = "[I/O] 3270"},
74 [IRQIO_TAP] = {.name = "TAP", .desc = "[I/O] Tape"},
75 [IRQIO_VMR] = {.name = "VMR", .desc = "[I/O] Unit Record Devices"},
76 [IRQIO_LCS] = {.name = "LCS", .desc = "[I/O] LCS"},
77 [IRQIO_CLW] = {.name = "CLW", .desc = "[I/O] CLAW"},
78 [IRQIO_CTC] = {.name = "CTC", .desc = "[I/O] CTC"},
79 [IRQIO_APB] = {.name = "APB", .desc = "[I/O] AP Bus"},
80 [IRQIO_ADM] = {.name = "ADM", .desc = "[I/O] EADM Subchannel"},
81 [IRQIO_CSC] = {.name = "CSC", .desc = "[I/O] CHSC Subchannel"},
82 [IRQIO_PCI] = {.name = "PCI", .desc = "[I/O] PCI Interrupt" },
83 [IRQIO_MSI] = {.name = "MSI", .desc = "[I/O] MSI Interrupt" },
84 [IRQIO_VIR] = {.name = "VIR", .desc = "[I/O] Virtual I/O Devices"},
85 [NMI_NMI] = {.name = "NMI", .desc = "[NMI] Machine Check"},
86 [CPU_RST] = {.name = "RST", .desc = "[CPU] CPU Restart"},
90 * show_interrupts is needed by /proc/interrupts.
92 int show_interrupts(struct seq_file *p, void *v)
94 int irq = *(loff_t *) v;
100 for_each_online_cpu(cpu)
101 seq_printf(p, "CPU%d ", cpu);
105 seq_printf(p, "%s: ", irqclass_main_desc[irq].name);
106 for_each_online_cpu(cpu)
107 seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[irq]);
111 for (irq = 0; irq < NR_ARCH_IRQS; irq++) {
112 seq_printf(p, "%s: ", irqclass_sub_desc[irq].name);
113 for_each_online_cpu(cpu)
114 seq_printf(p, "%10u ", per_cpu(irq_stat, cpu).irqs[irq]);
115 if (irqclass_sub_desc[irq].desc)
116 seq_printf(p, " %s", irqclass_sub_desc[irq].desc);
125 * Switch to the asynchronous interrupt stack for softirq execution.
127 asmlinkage void do_softirq(void)
129 unsigned long flags, old, new;
134 local_irq_save(flags);
136 if (local_softirq_pending()) {
137 /* Get current stack pointer. */
138 asm volatile("la %0,0(15)" : "=a" (old));
139 /* Check against async. stack address range. */
140 new = S390_lowcore.async_stack;
141 if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
142 /* Need to switch to the async. stack. */
143 new -= STACK_FRAME_OVERHEAD;
144 ((struct stack_frame *) new)->back_chain = old;
146 asm volatile(" la 15,0(%0)\n"
149 : : "a" (new), "a" (old),
151 : "0", "1", "2", "3", "4", "5", "14",
154 /* We are already on the async stack. */
159 local_irq_restore(flags);
162 #ifdef CONFIG_PROC_FS
163 void init_irq_proc(void)
165 struct proc_dir_entry *root_irq_dir;
167 root_irq_dir = proc_mkdir("irq", NULL);
168 create_prof_cpu_mask(root_irq_dir);
173 * ext_int_hash[index] is the list head for all external interrupts that hash
176 static struct list_head ext_int_hash[256];
178 struct ext_int_info {
179 ext_int_handler_t handler;
181 struct list_head entry;
185 /* ext_int_hash_lock protects the handler lists for external interrupts */
186 DEFINE_SPINLOCK(ext_int_hash_lock);
188 static void __init init_external_interrupts(void)
192 for (idx = 0; idx < ARRAY_SIZE(ext_int_hash); idx++)
193 INIT_LIST_HEAD(&ext_int_hash[idx]);
196 static inline int ext_hash(u16 code)
198 return (code + (code >> 9)) & 0xff;
201 int register_external_interrupt(u16 code, ext_int_handler_t handler)
203 struct ext_int_info *p;
207 p = kmalloc(sizeof(*p), GFP_ATOMIC);
211 p->handler = handler;
212 index = ext_hash(code);
214 spin_lock_irqsave(&ext_int_hash_lock, flags);
215 list_add_rcu(&p->entry, &ext_int_hash[index]);
216 spin_unlock_irqrestore(&ext_int_hash_lock, flags);
219 EXPORT_SYMBOL(register_external_interrupt);
221 int unregister_external_interrupt(u16 code, ext_int_handler_t handler)
223 struct ext_int_info *p;
225 int index = ext_hash(code);
227 spin_lock_irqsave(&ext_int_hash_lock, flags);
228 list_for_each_entry_rcu(p, &ext_int_hash[index], entry) {
229 if (p->code == code && p->handler == handler) {
230 list_del_rcu(&p->entry);
234 spin_unlock_irqrestore(&ext_int_hash_lock, flags);
237 EXPORT_SYMBOL(unregister_external_interrupt);
239 void __irq_entry do_extint(struct pt_regs *regs, struct ext_code ext_code,
240 unsigned int param32, unsigned long param64)
242 struct pt_regs *old_regs;
243 struct ext_int_info *p;
246 old_regs = set_irq_regs(regs);
248 if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator) {
249 /* Serve timer interrupts first. */
250 clock_comparator_work();
252 kstat_incr_irqs_this_cpu(EXTERNAL_INTERRUPT, NULL);
253 if (ext_code.code != 0x1004)
254 __get_cpu_var(s390_idle).nohz_delay = 1;
256 index = ext_hash(ext_code.code);
258 list_for_each_entry_rcu(p, &ext_int_hash[index], entry)
259 if (likely(p->code == ext_code.code))
260 p->handler(ext_code, param32, param64);
263 set_irq_regs(old_regs);
266 void __init init_IRQ(void)
268 init_external_interrupts();
271 static DEFINE_SPINLOCK(sc_irq_lock);
272 static int sc_irq_refcount;
274 void service_subclass_irq_register(void)
276 spin_lock(&sc_irq_lock);
277 if (!sc_irq_refcount)
280 spin_unlock(&sc_irq_lock);
282 EXPORT_SYMBOL(service_subclass_irq_register);
284 void service_subclass_irq_unregister(void)
286 spin_lock(&sc_irq_lock);
288 if (!sc_irq_refcount)
290 spin_unlock(&sc_irq_lock);
292 EXPORT_SYMBOL(service_subclass_irq_unregister);
294 static DEFINE_SPINLOCK(ma_subclass_lock);
295 static int ma_subclass_refcount;
297 void measurement_alert_subclass_register(void)
299 spin_lock(&ma_subclass_lock);
300 if (!ma_subclass_refcount)
302 ma_subclass_refcount++;
303 spin_unlock(&ma_subclass_lock);
305 EXPORT_SYMBOL(measurement_alert_subclass_register);
307 void measurement_alert_subclass_unregister(void)
309 spin_lock(&ma_subclass_lock);
310 ma_subclass_refcount--;
311 if (!ma_subclass_refcount)
313 spin_unlock(&ma_subclass_lock);
315 EXPORT_SYMBOL(measurement_alert_subclass_unregister);