diff options
Diffstat (limited to 'arch/s390/kernel/irq.c')
| -rw-r--r-- | arch/s390/kernel/irq.c | 137 |
1 files changed, 129 insertions, 8 deletions
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c index e204f9597aaf..e3264f6a9720 100644 --- a/arch/s390/kernel/irq.c +++ b/arch/s390/kernel/irq.c @@ -1,19 +1,28 @@ /* - * Copyright IBM Corp. 2004,2010 - * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), - * Thomas Spatzier (tspat@de.ibm.com) + * 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/module.h> -#include <linux/kernel.h> #include <linux/kernel_stat.h> #include <linux/interrupt.h> #include <linux/seq_file.h> -#include <linux/cpu.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; @@ -82,8 +91,7 @@ int show_interrupts(struct seq_file *p, void *v) * For compatibilty only. S/390 specific setup of interrupts et al. is done * much later in init_channel_subsystem(). */ -void __init -init_IRQ(void) +void __init init_IRQ(void) { /* nothing... */ } @@ -134,3 +142,116 @@ void init_irq_proc(void) create_prof_cpu_mask(root_irq_dir); } #endif + +/* + * ext_int_hash[index] is the start of the list for all external interrupts + * that hash to this index. With the current set of external interrupts + * (0x1202 external call, 0x1004 cpu timer, 0x2401 hwc console, 0x4000 + * iucv and 0x2603 pfault) this is always the first element. + */ + +struct ext_int_info { + struct ext_int_info *next; + ext_int_handler_t handler; + u16 code; +}; + +static struct ext_int_info *ext_int_hash[256]; + +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; + int index; + + p = kmalloc(sizeof(*p), GFP_ATOMIC); + if (!p) + return -ENOMEM; + p->code = code; + p->handler = handler; + index = ext_hash(code); + p->next = ext_int_hash[index]; + ext_int_hash[index] = p; + return 0; +} +EXPORT_SYMBOL(register_external_interrupt); + +int unregister_external_interrupt(u16 code, ext_int_handler_t handler) +{ + struct ext_int_info *p, *q; + int index; + + index = ext_hash(code); + q = NULL; + p = ext_int_hash[index]; + while (p) { + if (p->code == code && p->handler == handler) + break; + q = p; + p = p->next; + } + if (!p) + return -ENOENT; + if (q) + q->next = p->next; + else + ext_int_hash[index] = p->next; + kfree(p); + return 0; +} +EXPORT_SYMBOL(unregister_external_interrupt); + +void __irq_entry do_extint(struct pt_regs *regs, unsigned int ext_int_code, + unsigned int param32, unsigned long param64) +{ + struct pt_regs *old_regs; + unsigned short code; + struct ext_int_info *p; + int index; + + code = (unsigned short) ext_int_code; + old_regs = set_irq_regs(regs); + s390_idle_check(regs, S390_lowcore.int_clock, + S390_lowcore.async_enter_timer); + 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 (code != 0x1004) + __get_cpu_var(s390_idle).nohz_delay = 1; + index = ext_hash(code); + for (p = ext_int_hash[index]; p; p = p->next) { + if (likely(p->code == code)) + p->handler(ext_int_code, param32, param64); + } + irq_exit(); + set_irq_regs(old_regs); +} + +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); |