1/*
2 * ints.c - Generic interrupt controller support
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file COPYING in the main directory of this archive
6 * for more details.
7 *
8 * Copyright 1996 Roman Zippel
9 * Copyright 1999 D. Jeff Dionne <jeff@rt-control.com>
10 */
11
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/interrupt.h>
16#include <linux/irq.h>
17#include <linux/cpu.h>
18#include <asm/traps.h>
19#include <asm/io.h>
20#include <asm/machdep.h>
21
22#if defined(CONFIG_M68EZ328)
23#include <asm/MC68EZ328.h>
24#elif defined(CONFIG_M68VZ328)
25#include <asm/MC68VZ328.h>
26#else
27#include <asm/MC68328.h>
28#endif
29
30#include "ints.h"
31
32/* assembler routines */
33asmlinkage void system_call(void);
34asmlinkage void buserr(void);
35asmlinkage void trap(void);
36asmlinkage void trap3(void);
37asmlinkage void trap4(void);
38asmlinkage void trap5(void);
39asmlinkage void trap6(void);
40asmlinkage void trap7(void);
41asmlinkage void trap8(void);
42asmlinkage void trap9(void);
43asmlinkage void trap10(void);
44asmlinkage void trap11(void);
45asmlinkage void trap12(void);
46asmlinkage void trap13(void);
47asmlinkage void trap14(void);
48asmlinkage void trap15(void);
49asmlinkage void trap33(void);
50asmlinkage void trap34(void);
51asmlinkage void trap35(void);
52asmlinkage void trap36(void);
53asmlinkage void trap37(void);
54asmlinkage void trap38(void);
55asmlinkage void trap39(void);
56asmlinkage void trap40(void);
57asmlinkage void trap41(void);
58asmlinkage void trap42(void);
59asmlinkage void trap43(void);
60asmlinkage void trap44(void);
61asmlinkage void trap45(void);
62asmlinkage void trap46(void);
63asmlinkage void trap47(void);
64asmlinkage irqreturn_t bad_interrupt(int, void *);
65asmlinkage irqreturn_t inthandler(void);
66asmlinkage irqreturn_t inthandler1(void);
67asmlinkage irqreturn_t inthandler2(void);
68asmlinkage irqreturn_t inthandler3(void);
69asmlinkage irqreturn_t inthandler4(void);
70asmlinkage irqreturn_t inthandler5(void);
71asmlinkage irqreturn_t inthandler6(void);
72asmlinkage irqreturn_t inthandler7(void);
73
74/* The 68k family did not have a good way to determine the source
75 * of interrupts until later in the family. The EC000 core does
76 * not provide the vector number on the stack, we vector everything
77 * into one vector and look in the blasted mask register...
78 * This code is designed to be fast, almost constant time, not clean!
79 */
80asmlinkage void process_int(int vec, struct pt_regs *fp)
81{
82 int irq;
83 int mask;
84
85 unsigned long pend = ISR;
86
87 while (pend) {
88 if (pend & 0x0000ffff) {
89 if (pend & 0x000000ff) {
90 if (pend & 0x0000000f) {
91 mask = 0x00000001;
92 irq = 0;
93 } else {
94 mask = 0x00000010;
95 irq = 4;
96 }
97 } else {
98 if (pend & 0x00000f00) {
99 mask = 0x00000100;
100 irq = 8;
101 } else {
102 mask = 0x00001000;
103 irq = 12;
104 }
105 }
106 } else {
107 if (pend & 0x00ff0000) {
108 if (pend & 0x000f0000) {
109 mask = 0x00010000;
110 irq = 16;
111 } else {
112 mask = 0x00100000;
113 irq = 20;
114 }
115 } else {
116 if (pend & 0x0f000000) {
117 mask = 0x01000000;
118 irq = 24;
119 } else {
120 mask = 0x10000000;
121 irq = 28;
122 }
123 }
124 }
125
126 while (! (mask & pend)) {
127 mask <<=1;
128 irq++;
129 }
130
131 do_IRQ(irq, fp);
132 pend &= ~mask;
133 }
134}
135
136static void intc_irq_unmask(struct irq_data *d)
137{
138 IMR &= ~(1 << d->irq);
139}
140
141static void intc_irq_mask(struct irq_data *d)
142{
143 IMR |= (1 << d->irq);
144}
145
146static struct irq_chip intc_irq_chip = {
147 .name = "M68K-INTC",
148 .irq_mask = intc_irq_mask,
149 .irq_unmask = intc_irq_unmask,
150};
151
152/*
153 * This function should be called during kernel startup to initialize
154 * the machine vector table.
155 */
156void __init trap_init(void)
157{
158 int i;
159
160 /* set up the vectors */
161 for (i = 72; i < 256; ++i)
162 _ramvec[i] = (e_vector) bad_interrupt;
163
164 _ramvec[32] = system_call;
165
166 _ramvec[65] = (e_vector) inthandler1;
167 _ramvec[66] = (e_vector) inthandler2;
168 _ramvec[67] = (e_vector) inthandler3;
169 _ramvec[68] = (e_vector) inthandler4;
170 _ramvec[69] = (e_vector) inthandler5;
171 _ramvec[70] = (e_vector) inthandler6;
172 _ramvec[71] = (e_vector) inthandler7;
173}
174
175void __init init_IRQ(void)
176{
177 int i;
178
179 IVR = 0x40; /* Set DragonBall IVR (interrupt base) to 64 */
180
181 /* turn off all interrupts */
182 IMR = ~0;
183
184 for (i = 0; (i < NR_IRQS); i++) {
185 irq_set_chip(irq: i, chip: &intc_irq_chip);
186 irq_set_handler(irq: i, handle: handle_level_irq);
187 }
188}
189
190

source code of linux/arch/m68k/68000/ints.c