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