1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright IBM Corp. 2004, 2011
4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
5 * Holger Smolinski <Holger.Smolinski@de.ibm.com>,
6 * Thomas Spatzier <tspat@de.ibm.com>,
8 * This file contains interrupt related functions.
11 #include <linux/kernel_stat.h>
12 #include <linux/interrupt.h>
13 #include <linux/seq_file.h>
14 #include <linux/proc_fs.h>
15 #include <linux/profile.h>
16 #include <linux/export.h>
17 #include <linux/kernel.h>
18 #include <linux/ftrace.h>
19 #include <linux/errno.h>
20 #include <linux/slab.h>
21 #include <linux/init.h>
22 #include <linux/cpu.h>
23 #include <linux/irq.h>
24 #include <linux/entry-common.h>
25 #include <asm/irq_regs.h>
26 #include <asm/cputime.h>
27 #include <asm/lowcore.h>
29 #include <asm/hw_irq.h>
30 #include <asm/stacktrace.h>
31 #include <asm/softirq_stack.h>
34 DEFINE_PER_CPU_SHARED_ALIGNED(struct irq_stat, irq_stat);
35 EXPORT_PER_CPU_SYMBOL_GPL(irq_stat);
44 * The list of "main" irq classes on s390. This is the list of interrupts
45 * that appear both in /proc/stat ("intr" line) and /proc/interrupts.
46 * Historically only external and I/O interrupts have been part of /proc/stat.
47 * We can't add the split external and I/O sub classes since the first field
48 * in the "intr" line in /proc/stat is supposed to be the sum of all other
50 * Since the external and I/O interrupt fields are already sums we would end
51 * up with having a sum which accounts each interrupt twice.
53 static const struct irq_class irqclass_main_desc[NR_IRQS_BASE] = {
54 {.irq = EXT_INTERRUPT, .name = "EXT"},
55 {.irq = IO_INTERRUPT, .name = "I/O"},
56 {.irq = THIN_INTERRUPT, .name = "AIO"},
60 * The list of split external and I/O interrupts that appear only in
62 * In addition this list contains non external / I/O events like NMIs.
64 static const struct irq_class irqclass_sub_desc[] = {
65 {.irq = IRQEXT_CLK, .name = "CLK", .desc = "[EXT] Clock Comparator"},
66 {.irq = IRQEXT_EXC, .name = "EXC", .desc = "[EXT] External Call"},
67 {.irq = IRQEXT_EMS, .name = "EMS", .desc = "[EXT] Emergency Signal"},
68 {.irq = IRQEXT_TMR, .name = "TMR", .desc = "[EXT] CPU Timer"},
69 {.irq = IRQEXT_TLA, .name = "TAL", .desc = "[EXT] Timing Alert"},
70 {.irq = IRQEXT_PFL, .name = "PFL", .desc = "[EXT] Pseudo Page Fault"},
71 {.irq = IRQEXT_DSD, .name = "DSD", .desc = "[EXT] DASD Diag"},
72 {.irq = IRQEXT_VRT, .name = "VRT", .desc = "[EXT] Virtio"},
73 {.irq = IRQEXT_SCP, .name = "SCP", .desc = "[EXT] Service Call"},
74 {.irq = IRQEXT_IUC, .name = "IUC", .desc = "[EXT] IUCV"},
75 {.irq = IRQEXT_CMS, .name = "CMS", .desc = "[EXT] CPU-Measurement: Sampling"},
76 {.irq = IRQEXT_CMC, .name = "CMC", .desc = "[EXT] CPU-Measurement: Counter"},
77 {.irq = IRQEXT_FTP, .name = "FTP", .desc = "[EXT] HMC FTP Service"},
78 {.irq = IRQIO_CIO, .name = "CIO", .desc = "[I/O] Common I/O Layer Interrupt"},
79 {.irq = IRQIO_DAS, .name = "DAS", .desc = "[I/O] DASD"},
80 {.irq = IRQIO_C15, .name = "C15", .desc = "[I/O] 3215"},
81 {.irq = IRQIO_C70, .name = "C70", .desc = "[I/O] 3270"},
82 {.irq = IRQIO_TAP, .name = "TAP", .desc = "[I/O] Tape"},
83 {.irq = IRQIO_VMR, .name = "VMR", .desc = "[I/O] Unit Record Devices"},
84 {.irq = IRQIO_LCS, .name = "LCS", .desc = "[I/O] LCS"},
85 {.irq = IRQIO_CTC, .name = "CTC", .desc = "[I/O] CTC"},
86 {.irq = IRQIO_ADM, .name = "ADM", .desc = "[I/O] EADM Subchannel"},
87 {.irq = IRQIO_CSC, .name = "CSC", .desc = "[I/O] CHSC Subchannel"},
88 {.irq = IRQIO_VIR, .name = "VIR", .desc = "[I/O] Virtual I/O Devices"},
89 {.irq = IRQIO_QAI, .name = "QAI", .desc = "[AIO] QDIO Adapter Interrupt"},
90 {.irq = IRQIO_APB, .name = "APB", .desc = "[AIO] AP Bus"},
91 {.irq = IRQIO_PCF, .name = "PCF", .desc = "[AIO] PCI Floating Interrupt"},
92 {.irq = IRQIO_PCD, .name = "PCD", .desc = "[AIO] PCI Directed Interrupt"},
93 {.irq = IRQIO_MSI, .name = "MSI", .desc = "[AIO] MSI Interrupt"},
94 {.irq = IRQIO_VAI, .name = "VAI", .desc = "[AIO] Virtual I/O Devices AI"},
95 {.irq = IRQIO_GAL, .name = "GAL", .desc = "[AIO] GIB Alert"},
96 {.irq = NMI_NMI, .name = "NMI", .desc = "[NMI] Machine Check"},
97 {.irq = CPU_RST, .name = "RST", .desc = "[CPU] CPU Restart"},
100 static void do_IRQ(struct pt_regs *regs, int irq)
102 if (tod_after_eq(S390_lowcore.int_clock,
103 S390_lowcore.clock_comparator))
104 /* Serve timer interrupts first. */
105 clock_comparator_work();
106 generic_handle_irq(irq);
109 static int on_async_stack(void)
111 unsigned long frame = current_frame_address();
113 return ((S390_lowcore.async_stack ^ frame) & ~(THREAD_SIZE - 1)) == 0;
116 static void do_irq_async(struct pt_regs *regs, int irq)
118 if (on_async_stack()) {
121 call_on_stack(2, S390_lowcore.async_stack, void, do_IRQ,
122 struct pt_regs *, regs, int, irq);
126 static int irq_pending(struct pt_regs *regs)
130 asm volatile("tpi 0\n"
131 "ipm %0" : "=d" (cc) : : "cc");
135 void noinstr do_io_irq(struct pt_regs *regs)
137 irqentry_state_t state = irqentry_enter(regs);
138 struct pt_regs *old_regs = set_irq_regs(regs);
146 from_idle = !user_mode(regs) && regs->psw.addr == (unsigned long)psw_idle_exit;
148 account_idle_time_irq();
151 regs->tpi_info = S390_lowcore.tpi_info;
152 if (S390_lowcore.tpi_info.adapter_IO)
153 do_irq_async(regs, THIN_INTERRUPT);
155 do_irq_async(regs, IO_INTERRUPT);
156 } while (MACHINE_IS_LPAR && irq_pending(regs));
159 set_irq_regs(old_regs);
160 irqentry_exit(regs, state);
163 regs->psw.mask &= ~(PSW_MASK_EXT | PSW_MASK_IO | PSW_MASK_WAIT);
166 void noinstr do_ext_irq(struct pt_regs *regs)
168 irqentry_state_t state = irqentry_enter(regs);
169 struct pt_regs *old_regs = set_irq_regs(regs);
177 regs->int_code = S390_lowcore.ext_int_code_addr;
178 regs->int_parm = S390_lowcore.ext_params;
179 regs->int_parm_long = S390_lowcore.ext_params2;
181 from_idle = !user_mode(regs) && regs->psw.addr == (unsigned long)psw_idle_exit;
183 account_idle_time_irq();
185 do_irq_async(regs, EXT_INTERRUPT);
188 set_irq_regs(old_regs);
189 irqentry_exit(regs, state);
192 regs->psw.mask &= ~(PSW_MASK_EXT | PSW_MASK_IO | PSW_MASK_WAIT);
195 static void show_msi_interrupt(struct seq_file *p, int irq)
197 struct irq_desc *desc;
202 desc = irq_to_desc(irq);
206 raw_spin_lock_irqsave(&desc->lock, flags);
207 seq_printf(p, "%3d: ", irq);
208 for_each_online_cpu(cpu)
209 seq_printf(p, "%10u ", irq_desc_kstat_cpu(desc, cpu));
211 if (desc->irq_data.chip)
212 seq_printf(p, " %8s", desc->irq_data.chip->name);
215 seq_printf(p, " %s", desc->action->name);
218 raw_spin_unlock_irqrestore(&desc->lock, flags);
224 * show_interrupts is needed by /proc/interrupts.
226 int show_interrupts(struct seq_file *p, void *v)
228 int index = *(loff_t *) v;
234 for_each_online_cpu(cpu)
235 seq_printf(p, "CPU%-8d", cpu);
238 if (index < NR_IRQS_BASE) {
239 seq_printf(p, "%s: ", irqclass_main_desc[index].name);
240 irq = irqclass_main_desc[index].irq;
241 for_each_online_cpu(cpu)
242 seq_printf(p, "%10u ", kstat_irqs_cpu(irq, cpu));
246 if (index < nr_irqs) {
247 show_msi_interrupt(p, index);
250 for (index = 0; index < NR_ARCH_IRQS; index++) {
251 seq_printf(p, "%s: ", irqclass_sub_desc[index].name);
252 irq = irqclass_sub_desc[index].irq;
253 for_each_online_cpu(cpu)
254 seq_printf(p, "%10u ",
255 per_cpu(irq_stat, cpu).irqs[irq]);
256 if (irqclass_sub_desc[index].desc)
257 seq_printf(p, " %s", irqclass_sub_desc[index].desc);
265 unsigned int arch_dynirq_lower_bound(unsigned int from)
267 return from < NR_IRQS_BASE ? NR_IRQS_BASE : from;
271 * ext_int_hash[index] is the list head for all external interrupts that hash
274 static struct hlist_head ext_int_hash[32] ____cacheline_aligned;
276 struct ext_int_info {
277 ext_int_handler_t handler;
278 struct hlist_node entry;
283 /* ext_int_hash_lock protects the handler lists for external interrupts */
284 static DEFINE_SPINLOCK(ext_int_hash_lock);
286 static inline int ext_hash(u16 code)
288 BUILD_BUG_ON(!is_power_of_2(ARRAY_SIZE(ext_int_hash)));
290 return (code + (code >> 9)) & (ARRAY_SIZE(ext_int_hash) - 1);
293 int register_external_irq(u16 code, ext_int_handler_t handler)
295 struct ext_int_info *p;
299 p = kmalloc(sizeof(*p), GFP_ATOMIC);
303 p->handler = handler;
304 index = ext_hash(code);
306 spin_lock_irqsave(&ext_int_hash_lock, flags);
307 hlist_add_head_rcu(&p->entry, &ext_int_hash[index]);
308 spin_unlock_irqrestore(&ext_int_hash_lock, flags);
311 EXPORT_SYMBOL(register_external_irq);
313 int unregister_external_irq(u16 code, ext_int_handler_t handler)
315 struct ext_int_info *p;
317 int index = ext_hash(code);
319 spin_lock_irqsave(&ext_int_hash_lock, flags);
320 hlist_for_each_entry_rcu(p, &ext_int_hash[index], entry) {
321 if (p->code == code && p->handler == handler) {
322 hlist_del_rcu(&p->entry);
326 spin_unlock_irqrestore(&ext_int_hash_lock, flags);
329 EXPORT_SYMBOL(unregister_external_irq);
331 static irqreturn_t do_ext_interrupt(int irq, void *dummy)
333 struct pt_regs *regs = get_irq_regs();
334 struct ext_code ext_code;
335 struct ext_int_info *p;
338 ext_code = *(struct ext_code *) ®s->int_code;
339 if (ext_code.code != EXT_IRQ_CLK_COMP)
340 set_cpu_flag(CIF_NOHZ_DELAY);
342 index = ext_hash(ext_code.code);
344 hlist_for_each_entry_rcu(p, &ext_int_hash[index], entry) {
345 if (unlikely(p->code != ext_code.code))
347 p->handler(ext_code, regs->int_parm, regs->int_parm_long);
353 static void __init init_ext_interrupts(void)
357 for (idx = 0; idx < ARRAY_SIZE(ext_int_hash); idx++)
358 INIT_HLIST_HEAD(&ext_int_hash[idx]);
360 irq_set_chip_and_handler(EXT_INTERRUPT,
361 &dummy_irq_chip, handle_percpu_irq);
362 if (request_irq(EXT_INTERRUPT, do_ext_interrupt, 0, "EXT", NULL))
363 panic("Failed to register EXT interrupt\n");
366 void __init init_IRQ(void)
368 BUILD_BUG_ON(ARRAY_SIZE(irqclass_sub_desc) != NR_ARCH_IRQS);
369 init_cio_interrupts();
370 init_airq_interrupts();
371 init_ext_interrupts();
374 static DEFINE_SPINLOCK(irq_subclass_lock);
375 static unsigned char irq_subclass_refcount[64];
377 void irq_subclass_register(enum irq_subclass subclass)
379 spin_lock(&irq_subclass_lock);
380 if (!irq_subclass_refcount[subclass])
381 ctl_set_bit(0, subclass);
382 irq_subclass_refcount[subclass]++;
383 spin_unlock(&irq_subclass_lock);
385 EXPORT_SYMBOL(irq_subclass_register);
387 void irq_subclass_unregister(enum irq_subclass subclass)
389 spin_lock(&irq_subclass_lock);
390 irq_subclass_refcount[subclass]--;
391 if (!irq_subclass_refcount[subclass])
392 ctl_clear_bit(0, subclass);
393 spin_unlock(&irq_subclass_lock);
395 EXPORT_SYMBOL(irq_subclass_unregister);