cia.c
4.26 KB
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
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/*
* linux/arch/m68k/amiga/cia.c - CIA support
*
* Copyright (C) 1996 Roman Zippel
*
* The concept of some functions bases on the original Amiga OS function
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/kernel_stat.h>
#include <linux/init.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <asm/irq.h>
#include <asm/amigahw.h>
#include <asm/amigaints.h>
struct ciabase {
volatile struct CIA *cia;
unsigned char icr_mask, icr_data;
unsigned short int_mask;
int handler_irq, cia_irq, server_irq;
char *name;
} ciaa_base = {
.cia = &ciaa,
.int_mask = IF_PORTS,
.handler_irq = IRQ_AMIGA_PORTS,
.cia_irq = IRQ_AMIGA_CIAA,
.name = "CIAA"
}, ciab_base = {
.cia = &ciab,
.int_mask = IF_EXTER,
.handler_irq = IRQ_AMIGA_EXTER,
.cia_irq = IRQ_AMIGA_CIAB,
.name = "CIAB"
};
/*
* Cause or clear CIA interrupts, return old interrupt status.
*/
unsigned char cia_set_irq(struct ciabase *base, unsigned char mask)
{
unsigned char old;
old = (base->icr_data |= base->cia->icr);
if (mask & CIA_ICR_SETCLR)
base->icr_data |= mask;
else
base->icr_data &= ~mask;
if (base->icr_data & base->icr_mask)
amiga_custom.intreq = IF_SETCLR | base->int_mask;
return old & base->icr_mask;
}
/*
* Enable or disable CIA interrupts, return old interrupt mask,
*/
unsigned char cia_able_irq(struct ciabase *base, unsigned char mask)
{
unsigned char old;
old = base->icr_mask;
base->icr_data |= base->cia->icr;
base->cia->icr = mask;
if (mask & CIA_ICR_SETCLR)
base->icr_mask |= mask;
else
base->icr_mask &= ~mask;
base->icr_mask &= CIA_ICR_ALL;
if (base->icr_data & base->icr_mask)
amiga_custom.intreq = IF_SETCLR | base->int_mask;
return old;
}
static irqreturn_t cia_handler(int irq, void *dev_id)
{
struct ciabase *base = dev_id;
int mach_irq;
unsigned char ints;
mach_irq = base->cia_irq;
ints = cia_set_irq(base, CIA_ICR_ALL);
amiga_custom.intreq = base->int_mask;
for (; ints; mach_irq++, ints >>= 1) {
if (ints & 1)
generic_handle_irq(mach_irq);
}
return IRQ_HANDLED;
}
static void cia_irq_enable(struct irq_data *data)
{
unsigned int irq = data->irq;
unsigned char mask;
if (irq >= IRQ_AMIGA_CIAB) {
mask = 1 << (irq - IRQ_AMIGA_CIAB);
cia_set_irq(&ciab_base, mask);
cia_able_irq(&ciab_base, CIA_ICR_SETCLR | mask);
} else {
mask = 1 << (irq - IRQ_AMIGA_CIAA);
cia_set_irq(&ciaa_base, mask);
cia_able_irq(&ciaa_base, CIA_ICR_SETCLR | mask);
}
}
static void cia_irq_disable(struct irq_data *data)
{
unsigned int irq = data->irq;
if (irq >= IRQ_AMIGA_CIAB)
cia_able_irq(&ciab_base, 1 << (irq - IRQ_AMIGA_CIAB));
else
cia_able_irq(&ciaa_base, 1 << (irq - IRQ_AMIGA_CIAA));
}
static struct irq_chip cia_irq_chip = {
.name = "cia",
.irq_enable = cia_irq_enable,
.irq_disable = cia_irq_disable,
};
/*
* Override auto irq 2 & 6 and use them as general chain
* for external interrupts, we link the CIA interrupt sources
* into this chain.
*/
static void auto_irq_enable(struct irq_data *data)
{
switch (data->irq) {
case IRQ_AUTO_2:
amiga_custom.intena = IF_SETCLR | IF_PORTS;
break;
case IRQ_AUTO_6:
amiga_custom.intena = IF_SETCLR | IF_EXTER;
break;
}
}
static void auto_irq_disable(struct irq_data *data)
{
switch (data->irq) {
case IRQ_AUTO_2:
amiga_custom.intena = IF_PORTS;
break;
case IRQ_AUTO_6:
amiga_custom.intena = IF_EXTER;
break;
}
}
static struct irq_chip auto_irq_chip = {
.name = "auto",
.irq_enable = auto_irq_enable,
.irq_disable = auto_irq_disable,
};
void __init cia_init_IRQ(struct ciabase *base)
{
m68k_setup_irq_controller(&cia_irq_chip, handle_simple_irq,
base->cia_irq, CIA_IRQS);
/* clear any pending interrupt and turn off all interrupts */
cia_set_irq(base, CIA_ICR_ALL);
cia_able_irq(base, CIA_ICR_ALL);
/* override auto int and install CIA handler */
m68k_setup_irq_controller(&auto_irq_chip, handle_simple_irq,
base->handler_irq, 1);
m68k_irq_startup_irq(base->handler_irq);
if (request_irq(base->handler_irq, cia_handler, IRQF_SHARED,
base->name, base))
pr_err("Couldn't register %s interrupt\n", base->name);
}