| /* |
| * Copyright IBM Corp. 2004, 2011 |
| * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>, |
| * Holger Smolinski <Holger.Smolinski@de.ibm.com>, |
| * Thomas Spatzier <tspat@de.ibm.com>, |
| * |
| * This file contains interrupt related functions. |
| */ |
| |
| #include <linux/kernel_stat.h> |
| #include <linux/interrupt.h> |
| #include <linux/seq_file.h> |
| #include <linux/proc_fs.h> |
| #include <linux/profile.h> |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/ftrace.h> |
| #include <linux/errno.h> |
| #include <linux/slab.h> |
| #include <linux/cpu.h> |
| #include <asm/irq_regs.h> |
| #include <asm/cputime.h> |
| #include <asm/lowcore.h> |
| #include <asm/irq.h> |
| #include "entry.h" |
| |
| struct irq_class { |
| char *name; |
| char *desc; |
| }; |
| |
| static const struct irq_class intrclass_names[] = { |
| {.name = "EXT" }, |
| {.name = "I/O" }, |
| {.name = "CLK", .desc = "[EXT] Clock Comparator" }, |
| {.name = "EXC", .desc = "[EXT] External Call" }, |
| {.name = "EMS", .desc = "[EXT] Emergency Signal" }, |
| {.name = "TMR", .desc = "[EXT] CPU Timer" }, |
| {.name = "TAL", .desc = "[EXT] Timing Alert" }, |
| {.name = "PFL", .desc = "[EXT] Pseudo Page Fault" }, |
| {.name = "DSD", .desc = "[EXT] DASD Diag" }, |
| {.name = "VRT", .desc = "[EXT] Virtio" }, |
| {.name = "SCP", .desc = "[EXT] Service Call" }, |
| {.name = "IUC", .desc = "[EXT] IUCV" }, |
| {.name = "CMS", .desc = "[EXT] CPU-Measurement: Sampling" }, |
| {.name = "CMC", .desc = "[EXT] CPU-Measurement: Counter" }, |
| {.name = "CIO", .desc = "[I/O] Common I/O Layer Interrupt" }, |
| {.name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt" }, |
| {.name = "DAS", .desc = "[I/O] DASD" }, |
| {.name = "C15", .desc = "[I/O] 3215" }, |
| {.name = "C70", .desc = "[I/O] 3270" }, |
| {.name = "TAP", .desc = "[I/O] Tape" }, |
| {.name = "VMR", .desc = "[I/O] Unit Record Devices" }, |
| {.name = "LCS", .desc = "[I/O] LCS" }, |
| {.name = "CLW", .desc = "[I/O] CLAW" }, |
| {.name = "CTC", .desc = "[I/O] CTC" }, |
| {.name = "APB", .desc = "[I/O] AP Bus" }, |
| {.name = "CSC", .desc = "[I/O] CHSC Subchannel" }, |
| {.name = "NMI", .desc = "[NMI] Machine Check" }, |
| }; |
| |
| /* |
| * show_interrupts is needed by /proc/interrupts. |
| */ |
| int show_interrupts(struct seq_file *p, void *v) |
| { |
| int i = *(loff_t *) v, j; |
| |
| get_online_cpus(); |
| if (i == 0) { |
| seq_puts(p, " "); |
| for_each_online_cpu(j) |
| seq_printf(p, "CPU%d ",j); |
| seq_putc(p, '\n'); |
| } |
| |
| if (i < NR_IRQS) { |
| seq_printf(p, "%s: ", intrclass_names[i].name); |
| #ifndef CONFIG_SMP |
| seq_printf(p, "%10u ", kstat_irqs(i)); |
| #else |
| for_each_online_cpu(j) |
| seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); |
| #endif |
| if (intrclass_names[i].desc) |
| seq_printf(p, " %s", intrclass_names[i].desc); |
| seq_putc(p, '\n'); |
| } |
| put_online_cpus(); |
| return 0; |
| } |
| |
| /* |
| * Switch to the asynchronous interrupt stack for softirq execution. |
| */ |
| asmlinkage void do_softirq(void) |
| { |
| unsigned long flags, old, new; |
| |
| if (in_interrupt()) |
| return; |
| |
| local_irq_save(flags); |
| |
| if (local_softirq_pending()) { |
| /* Get current stack pointer. */ |
| asm volatile("la %0,0(15)" : "=a" (old)); |
| /* Check against async. stack address range. */ |
| new = S390_lowcore.async_stack; |
| if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) { |
| /* Need to switch to the async. stack. */ |
| new -= STACK_FRAME_OVERHEAD; |
| ((struct stack_frame *) new)->back_chain = old; |
| |
| asm volatile(" la 15,0(%0)\n" |
| " basr 14,%2\n" |
| " la 15,0(%1)\n" |
| : : "a" (new), "a" (old), |
| "a" (__do_softirq) |
| : "0", "1", "2", "3", "4", "5", "14", |
| "cc", "memory" ); |
| } else { |
| /* We are already on the async stack. */ |
| __do_softirq(); |
| } |
| } |
| |
| local_irq_restore(flags); |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| void init_irq_proc(void) |
| { |
| struct proc_dir_entry *root_irq_dir; |
| |
| root_irq_dir = proc_mkdir("irq", NULL); |
| create_prof_cpu_mask(root_irq_dir); |
| } |
| #endif |
| |
| /* |
| * ext_int_hash[index] is the list head for all external interrupts that hash |
| * to this index. |
| */ |
| static struct list_head ext_int_hash[256]; |
| |
| struct ext_int_info { |
| ext_int_handler_t handler; |
| u16 code; |
| struct list_head entry; |
| struct rcu_head rcu; |
| }; |
| |
| /* ext_int_hash_lock protects the handler lists for external interrupts */ |
| DEFINE_SPINLOCK(ext_int_hash_lock); |
| |
| static void __init init_external_interrupts(void) |
| { |
| int idx; |
| |
| for (idx = 0; idx < ARRAY_SIZE(ext_int_hash); idx++) |
| INIT_LIST_HEAD(&ext_int_hash[idx]); |
| } |
| |
| static inline int ext_hash(u16 code) |
| { |
| return (code + (code >> 9)) & 0xff; |
| } |
| |
| int register_external_interrupt(u16 code, ext_int_handler_t handler) |
| { |
| struct ext_int_info *p; |
| unsigned long flags; |
| int index; |
| |
| p = kmalloc(sizeof(*p), GFP_ATOMIC); |
| if (!p) |
| return -ENOMEM; |
| p->code = code; |
| p->handler = handler; |
| index = ext_hash(code); |
| |
| spin_lock_irqsave(&ext_int_hash_lock, flags); |
| list_add_rcu(&p->entry, &ext_int_hash[index]); |
| spin_unlock_irqrestore(&ext_int_hash_lock, flags); |
| return 0; |
| } |
| EXPORT_SYMBOL(register_external_interrupt); |
| |
| int unregister_external_interrupt(u16 code, ext_int_handler_t handler) |
| { |
| struct ext_int_info *p; |
| unsigned long flags; |
| int index = ext_hash(code); |
| |
| spin_lock_irqsave(&ext_int_hash_lock, flags); |
| list_for_each_entry_rcu(p, &ext_int_hash[index], entry) { |
| if (p->code == code && p->handler == handler) { |
| list_del_rcu(&p->entry); |
| kfree_rcu(p, rcu); |
| } |
| } |
| spin_unlock_irqrestore(&ext_int_hash_lock, flags); |
| return 0; |
| } |
| EXPORT_SYMBOL(unregister_external_interrupt); |
| |
| void __irq_entry do_extint(struct pt_regs *regs, struct ext_code ext_code, |
| unsigned int param32, unsigned long param64) |
| { |
| struct pt_regs *old_regs; |
| struct ext_int_info *p; |
| int index; |
| |
| old_regs = set_irq_regs(regs); |
| irq_enter(); |
| if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator) { |
| /* Serve timer interrupts first. */ |
| clock_comparator_work(); |
| } |
| kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++; |
| if (ext_code.code != 0x1004) |
| __get_cpu_var(s390_idle).nohz_delay = 1; |
| |
| index = ext_hash(ext_code.code); |
| rcu_read_lock(); |
| list_for_each_entry_rcu(p, &ext_int_hash[index], entry) |
| if (likely(p->code == ext_code.code)) |
| p->handler(ext_code, param32, param64); |
| rcu_read_unlock(); |
| irq_exit(); |
| set_irq_regs(old_regs); |
| } |
| |
| void __init init_IRQ(void) |
| { |
| init_external_interrupts(); |
| } |
| |
| static DEFINE_SPINLOCK(sc_irq_lock); |
| static int sc_irq_refcount; |
| |
| void service_subclass_irq_register(void) |
| { |
| spin_lock(&sc_irq_lock); |
| if (!sc_irq_refcount) |
| ctl_set_bit(0, 9); |
| sc_irq_refcount++; |
| spin_unlock(&sc_irq_lock); |
| } |
| EXPORT_SYMBOL(service_subclass_irq_register); |
| |
| void service_subclass_irq_unregister(void) |
| { |
| spin_lock(&sc_irq_lock); |
| sc_irq_refcount--; |
| if (!sc_irq_refcount) |
| ctl_clear_bit(0, 9); |
| spin_unlock(&sc_irq_lock); |
| } |
| EXPORT_SYMBOL(service_subclass_irq_unregister); |
| |
| static DEFINE_SPINLOCK(ma_subclass_lock); |
| static int ma_subclass_refcount; |
| |
| void measurement_alert_subclass_register(void) |
| { |
| spin_lock(&ma_subclass_lock); |
| if (!ma_subclass_refcount) |
| ctl_set_bit(0, 5); |
| ma_subclass_refcount++; |
| spin_unlock(&ma_subclass_lock); |
| } |
| EXPORT_SYMBOL(measurement_alert_subclass_register); |
| |
| void measurement_alert_subclass_unregister(void) |
| { |
| spin_lock(&ma_subclass_lock); |
| ma_subclass_refcount--; |
| if (!ma_subclass_refcount) |
| ctl_clear_bit(0, 5); |
| spin_unlock(&ma_subclass_lock); |
| } |
| EXPORT_SYMBOL(measurement_alert_subclass_unregister); |