Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/xtensa/kernel/irq.c |
| 3 | * |
| 4 | * Xtensa built-in interrupt controller and some generic functions copied |
| 5 | * from i386. |
| 6 | * |
| 7 | * Copyright (C) 2002 - 2005 Tensilica, Inc. |
| 8 | * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar |
| 9 | * |
| 10 | * |
| 11 | * Chris Zankel <chris@zankel.net> |
| 12 | * Kevin Chea |
| 13 | * |
| 14 | */ |
| 15 | |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/seq_file.h> |
| 18 | #include <linux/interrupt.h> |
| 19 | #include <linux/irq.h> |
| 20 | #include <linux/kernel_stat.h> |
| 21 | |
| 22 | #include <asm/uaccess.h> |
| 23 | #include <asm/platform.h> |
| 24 | |
| 25 | static void enable_xtensa_irq(unsigned int irq); |
| 26 | static void disable_xtensa_irq(unsigned int irq); |
| 27 | static void mask_and_ack_xtensa(unsigned int irq); |
| 28 | static void end_xtensa_irq(unsigned int irq); |
| 29 | |
| 30 | static unsigned int cached_irq_mask; |
| 31 | |
| 32 | atomic_t irq_err_count; |
| 33 | |
| 34 | /* |
| 35 | * 'what should we do if we get a hw irq event on an illegal vector'. |
| 36 | * each architecture has to answer this themselves. |
| 37 | */ |
| 38 | void ack_bad_irq(unsigned int irq) |
| 39 | { |
| 40 | printk("unexpected IRQ trap at vector %02x\n", irq); |
| 41 | } |
| 42 | |
| 43 | /* |
| 44 | * do_IRQ handles all normal device IRQ's (the special |
| 45 | * SMP cross-CPU interrupts have their own specific |
| 46 | * handlers). |
| 47 | */ |
| 48 | |
| 49 | unsigned int do_IRQ(int irq, struct pt_regs *regs) |
| 50 | { |
| 51 | irq_enter(); |
| 52 | |
| 53 | #ifdef CONFIG_DEBUG_STACKOVERFLOW |
| 54 | /* Debugging check for stack overflow: is there less than 1KB free? */ |
| 55 | { |
| 56 | unsigned long sp; |
| 57 | |
| 58 | __asm__ __volatile__ ("mov %0, a1\n" : "=a" (sp)); |
| 59 | sp &= THREAD_SIZE - 1; |
| 60 | |
| 61 | if (unlikely(sp < (sizeof(thread_info) + 1024))) |
| 62 | printk("Stack overflow in do_IRQ: %ld\n", |
| 63 | sp - sizeof(struct thread_info)); |
| 64 | } |
| 65 | #endif |
| 66 | |
| 67 | __do_IRQ(irq, regs); |
| 68 | |
| 69 | irq_exit(); |
| 70 | |
| 71 | return 1; |
| 72 | } |
| 73 | |
| 74 | /* |
| 75 | * Generic, controller-independent functions: |
| 76 | */ |
| 77 | |
| 78 | int show_interrupts(struct seq_file *p, void *v) |
| 79 | { |
| 80 | int i = *(loff_t *) v, j; |
| 81 | struct irqaction * action; |
| 82 | unsigned long flags; |
| 83 | |
| 84 | if (i == 0) { |
| 85 | seq_printf(p, " "); |
Andrew Morton | 394e390 | 2006-03-23 03:01:05 -0800 | [diff] [blame] | 86 | for_each_online_cpu(j) |
| 87 | seq_printf(p, "CPU%d ",j); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 88 | seq_putc(p, '\n'); |
| 89 | } |
| 90 | |
| 91 | if (i < NR_IRQS) { |
| 92 | spin_lock_irqsave(&irq_desc[i].lock, flags); |
| 93 | action = irq_desc[i].action; |
| 94 | if (!action) |
| 95 | goto skip; |
| 96 | seq_printf(p, "%3d: ",i); |
| 97 | #ifndef CONFIG_SMP |
| 98 | seq_printf(p, "%10u ", kstat_irqs(i)); |
| 99 | #else |
Andrew Morton | 394e390 | 2006-03-23 03:01:05 -0800 | [diff] [blame] | 100 | for_each_online_cpu(j) |
| 101 | seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 102 | #endif |
| 103 | seq_printf(p, " %14s", irq_desc[i].handler->typename); |
| 104 | seq_printf(p, " %s", action->name); |
| 105 | |
| 106 | for (action=action->next; action; action = action->next) |
| 107 | seq_printf(p, ", %s", action->name); |
| 108 | |
| 109 | seq_putc(p, '\n'); |
| 110 | skip: |
| 111 | spin_unlock_irqrestore(&irq_desc[i].lock, flags); |
| 112 | } else if (i == NR_IRQS) { |
| 113 | seq_printf(p, "NMI: "); |
Andrew Morton | 394e390 | 2006-03-23 03:01:05 -0800 | [diff] [blame] | 114 | for_each_online_cpu(j) |
| 115 | seq_printf(p, "%10u ", nmi_count(j)); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 116 | seq_putc(p, '\n'); |
| 117 | seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); |
| 118 | } |
| 119 | return 0; |
| 120 | } |
| 121 | /* shutdown is same as "disable" */ |
| 122 | #define shutdown_xtensa_irq disable_xtensa_irq |
| 123 | |
| 124 | static unsigned int startup_xtensa_irq(unsigned int irq) |
| 125 | { |
| 126 | enable_xtensa_irq(irq); |
| 127 | return 0; /* never anything pending */ |
| 128 | } |
| 129 | |
| 130 | static struct hw_interrupt_type xtensa_irq_type = { |
| 131 | "Xtensa-IRQ", |
| 132 | startup_xtensa_irq, |
| 133 | shutdown_xtensa_irq, |
| 134 | enable_xtensa_irq, |
| 135 | disable_xtensa_irq, |
| 136 | mask_and_ack_xtensa, |
| 137 | end_xtensa_irq |
| 138 | }; |
| 139 | |
| 140 | static inline void mask_irq(unsigned int irq) |
| 141 | { |
| 142 | cached_irq_mask &= ~(1 << irq); |
| 143 | set_sr (cached_irq_mask, INTENABLE); |
| 144 | } |
| 145 | |
| 146 | static inline void unmask_irq(unsigned int irq) |
| 147 | { |
| 148 | cached_irq_mask |= 1 << irq; |
| 149 | set_sr (cached_irq_mask, INTENABLE); |
| 150 | } |
| 151 | |
| 152 | static void disable_xtensa_irq(unsigned int irq) |
| 153 | { |
| 154 | unsigned long flags; |
| 155 | local_save_flags(flags); |
| 156 | mask_irq(irq); |
| 157 | local_irq_restore(flags); |
| 158 | } |
| 159 | |
| 160 | static void enable_xtensa_irq(unsigned int irq) |
| 161 | { |
| 162 | unsigned long flags; |
| 163 | local_save_flags(flags); |
| 164 | unmask_irq(irq); |
| 165 | local_irq_restore(flags); |
| 166 | } |
| 167 | |
| 168 | static void mask_and_ack_xtensa(unsigned int irq) |
| 169 | { |
| 170 | disable_xtensa_irq(irq); |
| 171 | } |
| 172 | |
| 173 | static void end_xtensa_irq(unsigned int irq) |
| 174 | { |
| 175 | enable_xtensa_irq(irq); |
| 176 | } |
| 177 | |
| 178 | |
| 179 | void __init init_IRQ(void) |
| 180 | { |
| 181 | int i; |
| 182 | |
| 183 | for (i=0; i < XTENSA_NR_IRQS; i++) |
| 184 | irq_desc[i].handler = &xtensa_irq_type; |
| 185 | |
| 186 | cached_irq_mask = 0; |
| 187 | |
| 188 | platform_init_irq(); |
| 189 | } |