Commit | Line | Data |
---|---|---|
1394f032 BW |
1 | /* |
2 | * File: arch/blackfin/kernel/irqchip.c | |
3 | * Based on: | |
4 | * Author: | |
5 | * | |
6 | * Created: | |
7 | * Description: This file contains the simple DMA Implementation for Blackfin | |
8 | * | |
9 | * Modified: | |
10 | * Copyright 2004-2006 Analog Devices Inc. | |
11 | * | |
12 | * Bugs: Enter bugs at http://blackfin.uclinux.org/ | |
13 | * | |
14 | * This program is free software; you can redistribute it and/or modify | |
15 | * it under the terms of the GNU General Public License as published by | |
16 | * the Free Software Foundation; either version 2 of the License, or | |
17 | * (at your option) any later version. | |
18 | * | |
19 | * This program is distributed in the hope that it will be useful, | |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
22 | * GNU General Public License for more details. | |
23 | * | |
24 | * You should have received a copy of the GNU General Public License | |
25 | * along with this program; if not, see the file COPYING, or write | |
26 | * to the Free Software Foundation, Inc., | |
27 | * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
28 | */ | |
29 | ||
30 | #include <linux/kernel_stat.h> | |
31 | #include <linux/module.h> | |
32 | #include <linux/random.h> | |
33 | #include <linux/seq_file.h> | |
34 | #include <linux/kallsyms.h> | |
35 | #include <linux/interrupt.h> | |
36 | #include <linux/irq.h> | |
518039bc | 37 | #include <asm/trace.h> |
1394f032 | 38 | |
8f65873e | 39 | static atomic_t irq_err_count; |
1394f032 BW |
40 | static spinlock_t irq_controller_lock; |
41 | ||
42 | /* | |
43 | * Dummy mask/unmask handler | |
44 | */ | |
45 | void dummy_mask_unmask_irq(unsigned int irq) | |
46 | { | |
47 | } | |
48 | ||
49 | void ack_bad_irq(unsigned int irq) | |
50 | { | |
8f65873e | 51 | atomic_inc(&irq_err_count); |
1394f032 BW |
52 | printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq); |
53 | } | |
1394f032 BW |
54 | |
55 | static struct irq_chip bad_chip = { | |
56 | .ack = dummy_mask_unmask_irq, | |
57 | .mask = dummy_mask_unmask_irq, | |
58 | .unmask = dummy_mask_unmask_irq, | |
59 | }; | |
60 | ||
61 | static struct irq_desc bad_irq_desc = { | |
71a7d155 | 62 | .status = IRQ_DISABLED, |
1394f032 BW |
63 | .chip = &bad_chip, |
64 | .handle_irq = handle_bad_irq, | |
65 | .depth = 1, | |
71a7d155 SZ |
66 | .lock = __SPIN_LOCK_UNLOCKED(irq_desc->lock), |
67 | #ifdef CONFIG_SMP | |
68 | .affinity = CPU_MASK_ALL | |
69 | #endif | |
1394f032 BW |
70 | }; |
71 | ||
72 | int show_interrupts(struct seq_file *p, void *v) | |
73 | { | |
8f65873e | 74 | int i = *(loff_t *) v, j; |
1394f032 BW |
75 | struct irqaction *action; |
76 | unsigned long flags; | |
77 | ||
78 | if (i < NR_IRQS) { | |
79 | spin_lock_irqsave(&irq_desc[i].lock, flags); | |
80 | action = irq_desc[i].action; | |
81 | if (!action) | |
8f65873e GY |
82 | goto skip; |
83 | seq_printf(p, "%3d: ", i); | |
84 | for_each_online_cpu(j) | |
85 | seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); | |
86 | seq_printf(p, " %8s", irq_desc[i].chip->name); | |
1394f032 BW |
87 | seq_printf(p, " %s", action->name); |
88 | for (action = action->next; action; action = action->next) | |
8f65873e | 89 | seq_printf(p, " %s", action->name); |
1394f032 BW |
90 | |
91 | seq_putc(p, '\n'); | |
8f65873e | 92 | skip: |
1394f032 | 93 | spin_unlock_irqrestore(&irq_desc[i].lock, flags); |
8f65873e GY |
94 | } else if (i == NR_IRQS) |
95 | seq_printf(p, "Err: %10u\n", atomic_read(&irq_err_count)); | |
1394f032 BW |
96 | return 0; |
97 | } | |
98 | ||
99 | /* | |
d2d50aa9 | 100 | * do_IRQ handles all hardware IRQs. Decoded IRQs should not |
1394f032 BW |
101 | * come via this function. Instead, they should provide their |
102 | * own 'handler' | |
103 | */ | |
1394f032 | 104 | #ifdef CONFIG_DO_IRQ_L1 |
f0b5d12f | 105 | __attribute__((l1_text)) |
1394f032 | 106 | #endif |
1394f032 BW |
107 | asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) |
108 | { | |
109 | struct pt_regs *old_regs; | |
110 | struct irq_desc *desc = irq_desc + irq; | |
111 | unsigned short pending, other_ints; | |
112 | ||
113 | old_regs = set_irq_regs(regs); | |
114 | ||
115 | /* | |
116 | * Some hardware gives randomly wrong interrupts. Rather | |
117 | * than crashing, do something sensible. | |
118 | */ | |
119 | if (irq >= NR_IRQS) | |
120 | desc = &bad_irq_desc; | |
121 | ||
122 | irq_enter(); | |
a45d575f RG |
123 | #ifdef CONFIG_DEBUG_STACKOVERFLOW |
124 | /* Debugging check for stack overflow: is there less than STACK_WARN free? */ | |
125 | { | |
126 | long sp; | |
127 | ||
128 | sp = __get_SP() & (THREAD_SIZE-1); | |
129 | ||
130 | if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) { | |
131 | dump_stack(); | |
132 | printk(KERN_EMERG "%s: possible stack overflow while handling irq %i " | |
133 | " only %ld bytes free\n", | |
134 | __func__, irq, sp - sizeof(struct thread_info)); | |
135 | } | |
136 | } | |
137 | #endif | |
1394f032 BW |
138 | generic_handle_irq(irq); |
139 | ||
140 | /* If we're the only interrupt running (ignoring IRQ15 which is for | |
141 | syscalls), lower our priority to IRQ14 so that softirqs run at | |
142 | that level. If there's another, lower-level interrupt, irq_exit | |
143 | will defer softirqs to that. */ | |
144 | CSYNC(); | |
145 | pending = bfin_read_IPEND() & ~0x8000; | |
146 | other_ints = pending & (pending - 1); | |
147 | if (other_ints == 0) | |
148 | lower_to_irq14(); | |
149 | irq_exit(); | |
150 | ||
151 | set_irq_regs(old_regs); | |
152 | } | |
153 | ||
154 | void __init init_IRQ(void) | |
155 | { | |
156 | struct irq_desc *desc; | |
157 | int irq; | |
158 | ||
159 | spin_lock_init(&irq_controller_lock); | |
160 | for (irq = 0, desc = irq_desc; irq < NR_IRQS; irq++, desc++) { | |
161 | *desc = bad_irq_desc; | |
162 | } | |
163 | ||
164 | init_arch_irq(); | |
518039bc RG |
165 | |
166 | #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND | |
167 | /* Now that evt_ivhw is set up, turn this on */ | |
168 | trace_buff_offset = 0; | |
169 | bfin_write_TBUFCTL(BFIN_TRACE_ON); | |
170 | printk(KERN_INFO "Hardware Trace expanded to %ik\n", | |
171 | 1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN); | |
172 | #endif | |
1394f032 | 173 | } |