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
|
/*
* arch/s390/kernel/s390_ext.c
*
* S390 version
* Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Holger Smolinski (Holger.Smolinski@de.ibm.com),
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/kernel_stat.h>
#include <linux/interrupt.h>
#include <asm/lowcore.h>
#include <asm/s390_ext.h>
#include <asm/irq_regs.h>
#include <asm/irq.h>
/*
* 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.
*/
ext_int_info_t *ext_int_hash[256] = { NULL, };
static inline int ext_hash(__u16 code)
{
return (code + (code >> 9)) & 0xff;
}
int register_external_interrupt(__u16 code, ext_int_handler_t handler)
{
ext_int_info_t *p;
int index;
p = kmalloc(sizeof(ext_int_info_t), GFP_ATOMIC);
if (p == NULL)
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;
}
int register_early_external_interrupt(__u16 code, ext_int_handler_t handler,
ext_int_info_t *p)
{
int index;
if (p == NULL)
return -EINVAL;
p->code = code;
p->handler = handler;
index = ext_hash(code);
p->next = ext_int_hash[index];
ext_int_hash[index] = p;
return 0;
}
int unregister_external_interrupt(__u16 code, ext_int_handler_t handler)
{
ext_int_info_t *p, *q;
int index;
index = ext_hash(code);
q = NULL;
p = ext_int_hash[index];
while (p != NULL) {
if (p->code == code && p->handler == handler)
break;
q = p;
p = p->next;
}
if (p == NULL)
return -ENOENT;
if (q != NULL)
q->next = p->next;
else
ext_int_hash[index] = p->next;
kfree(p);
return 0;
}
int unregister_early_external_interrupt(__u16 code, ext_int_handler_t handler,
ext_int_info_t *p)
{
ext_int_info_t *q;
int index;
if (p == NULL || p->code != code || p->handler != handler)
return -EINVAL;
index = ext_hash(code);
q = ext_int_hash[index];
if (p != q) {
while (q != NULL) {
if (q->next == p)
break;
q = q->next;
}
if (q == NULL)
return -ENOENT;
q->next = p->next;
} else
ext_int_hash[index] = p->next;
return 0;
}
void do_extint(struct pt_regs *regs, unsigned short code)
{
ext_int_info_t *p;
int index;
struct pt_regs *old_regs;
old_regs = set_irq_regs(regs);
irq_enter();
asm volatile ("mc 0,0");
if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer)
/**
* Make sure that the i/o interrupt did not "overtake"
* the last HZ timer interrupt.
*/
account_ticks(S390_lowcore.int_clock);
kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++;
index = ext_hash(code);
for (p = ext_int_hash[index]; p; p = p->next) {
if (likely(p->code == code))
p->handler(code);
}
irq_exit();
set_irq_regs(old_regs);
}
EXPORT_SYMBOL(register_external_interrupt);
EXPORT_SYMBOL(unregister_external_interrupt);
|
