Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * arch/s390/kernel/irq.c |
| 3 | * |
Heiko Carstens | 55dff52 | 2007-02-05 21:16:44 +0100 | [diff] [blame] | 4 | * Copyright IBM Corp. 2004,2007 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), |
Heiko Carstens | 55dff52 | 2007-02-05 21:16:44 +0100 | [diff] [blame] | 6 | * Thomas Spatzier (tspat@de.ibm.com) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | * |
| 8 | * This file contains interrupt related functions. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/kernel_stat.h> |
| 14 | #include <linux/interrupt.h> |
| 15 | #include <linux/seq_file.h> |
| 16 | #include <linux/cpu.h> |
Heiko Carstens | 55dff52 | 2007-02-05 21:16:44 +0100 | [diff] [blame] | 17 | #include <linux/proc_fs.h> |
| 18 | #include <linux/profile.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | |
| 20 | /* |
| 21 | * show_interrupts is needed by /proc/interrupts. |
| 22 | */ |
| 23 | int show_interrupts(struct seq_file *p, void *v) |
| 24 | { |
| 25 | static const char *intrclass_names[] = { "EXT", "I/O", }; |
| 26 | int i = *(loff_t *) v, j; |
| 27 | |
Heiko Carstens | 8dd79cb | 2008-05-15 16:52:39 +0200 | [diff] [blame] | 28 | get_online_cpus(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | if (i == 0) { |
| 30 | seq_puts(p, " "); |
| 31 | for_each_online_cpu(j) |
| 32 | seq_printf(p, "CPU%d ",j); |
| 33 | seq_putc(p, '\n'); |
| 34 | } |
| 35 | |
| 36 | if (i < NR_IRQS) { |
| 37 | seq_printf(p, "%s: ", intrclass_names[i]); |
| 38 | #ifndef CONFIG_SMP |
| 39 | seq_printf(p, "%10u ", kstat_irqs(i)); |
| 40 | #else |
| 41 | for_each_online_cpu(j) |
| 42 | seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); |
| 43 | #endif |
| 44 | seq_putc(p, '\n'); |
| 45 | |
| 46 | } |
Heiko Carstens | 8dd79cb | 2008-05-15 16:52:39 +0200 | [diff] [blame] | 47 | put_online_cpus(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | return 0; |
| 49 | } |
| 50 | |
| 51 | /* |
| 52 | * For compatibilty only. S/390 specific setup of interrupts et al. is done |
| 53 | * much later in init_channel_subsystem(). |
| 54 | */ |
| 55 | void __init |
| 56 | init_IRQ(void) |
| 57 | { |
| 58 | /* nothing... */ |
| 59 | } |
| 60 | |
| 61 | /* |
| 62 | * Switch to the asynchronous interrupt stack for softirq execution. |
| 63 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | asmlinkage void do_softirq(void) |
| 65 | { |
| 66 | unsigned long flags, old, new; |
| 67 | |
| 68 | if (in_interrupt()) |
| 69 | return; |
| 70 | |
| 71 | local_irq_save(flags); |
| 72 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | if (local_softirq_pending()) { |
| 74 | /* Get current stack pointer. */ |
| 75 | asm volatile("la %0,0(15)" : "=a" (old)); |
| 76 | /* Check against async. stack address range. */ |
| 77 | new = S390_lowcore.async_stack; |
| 78 | if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) { |
| 79 | /* Need to switch to the async. stack. */ |
| 80 | new -= STACK_FRAME_OVERHEAD; |
| 81 | ((struct stack_frame *) new)->back_chain = old; |
| 82 | |
| 83 | asm volatile(" la 15,0(%0)\n" |
| 84 | " basr 14,%2\n" |
| 85 | " la 15,0(%1)\n" |
| 86 | : : "a" (new), "a" (old), |
| 87 | "a" (__do_softirq) |
| 88 | : "0", "1", "2", "3", "4", "5", "14", |
| 89 | "cc", "memory" ); |
| 90 | } else |
| 91 | /* We are already on the async stack. */ |
| 92 | __do_softirq(); |
| 93 | } |
| 94 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | local_irq_restore(flags); |
| 96 | } |
Heiko Carstens | 55dff52 | 2007-02-05 21:16:44 +0100 | [diff] [blame] | 97 | |
| 98 | void init_irq_proc(void) |
| 99 | { |
| 100 | struct proc_dir_entry *root_irq_dir; |
| 101 | |
| 102 | root_irq_dir = proc_mkdir("irq", NULL); |
| 103 | create_prof_cpu_mask(root_irq_dir); |
| 104 | } |