1 /*
2 * Copyright 2001 MontaVista Software Inc.
3 * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
4 *
5 * arch/mips/ddb5xxx/ddb5477/irq_5477.c
6 * This file defines the irq handler for Vrc5477.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 *
13 */
14
15 /*
16 * Vrc5477 defines 32 IRQs.
17 *
18 * This file exports one function:
19 * vrc5477_irq_init(u32 irq_base);
20 */
21
22 #include <linux/interrupt.h>
23 #include <linux/types.h>
24 #include <linux/ptrace.h>
25
26 #include <asm/debug.h>
27
28 #include <asm/ddb5xxx/ddb5xxx.h>
29
30 /* number of total irqs supported by Vrc5477 */
31 #define NUM_5477_IRQ 32
32
33 static int vrc5477_irq_base = -1;
34
35
36 static void
vrc5477_irq_enable(unsigned int irq)37 vrc5477_irq_enable(unsigned int irq)
38 {
39 db_assert(vrc5477_irq_base != -1);
40 db_assert(irq >= vrc5477_irq_base);
41 db_assert(irq < vrc5477_irq_base+ NUM_5477_IRQ);
42
43 ll_vrc5477_irq_enable(irq - vrc5477_irq_base);
44 }
45
46 static void
vrc5477_irq_disable(unsigned int irq)47 vrc5477_irq_disable(unsigned int irq)
48 {
49 db_assert(vrc5477_irq_base != -1);
50 db_assert(irq >= vrc5477_irq_base);
51 db_assert(irq < vrc5477_irq_base + NUM_5477_IRQ);
52
53 ll_vrc5477_irq_disable(irq - vrc5477_irq_base);
54 }
55
vrc5477_irq_startup(unsigned int irq)56 static unsigned int vrc5477_irq_startup(unsigned int irq)
57 {
58 vrc5477_irq_enable(irq);
59 return 0;
60 }
61
62 #define vrc5477_irq_shutdown vrc5477_irq_disable
63
64 static void
vrc5477_irq_ack(unsigned int irq)65 vrc5477_irq_ack(unsigned int irq)
66 {
67 db_assert(vrc5477_irq_base != -1);
68 db_assert(irq >= vrc5477_irq_base);
69 db_assert(irq < vrc5477_irq_base+ NUM_5477_IRQ);
70
71 /* clear the interrupt bit */
72 /* some irqs require the driver to clear the sources */
73 ddb_out32(DDB_INTCLR32, 1 << (irq - vrc5477_irq_base));
74
75 /* disable interrupt - some handler will re-enable the irq
76 * and if the interrupt is leveled, we will have infinite loop
77 */
78 ll_vrc5477_irq_disable(irq - vrc5477_irq_base);
79 }
80
81 static void
vrc5477_irq_end(unsigned int irq)82 vrc5477_irq_end(unsigned int irq)
83 {
84 db_assert(vrc5477_irq_base != -1);
85 db_assert(irq >= vrc5477_irq_base);
86 db_assert(irq < vrc5477_irq_base + NUM_5477_IRQ);
87
88 if(!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
89 ll_vrc5477_irq_enable( irq - vrc5477_irq_base);
90 }
91
92 hw_irq_controller vrc5477_irq_controller = {
93 "vrc5477_irq",
94 vrc5477_irq_startup,
95 vrc5477_irq_shutdown,
96 vrc5477_irq_enable,
97 vrc5477_irq_disable,
98 vrc5477_irq_ack,
99 vrc5477_irq_end,
100 NULL /* no affinity stuff for UP */
101 };
102
103 void
vrc5477_irq_init(u32 irq_base)104 vrc5477_irq_init(u32 irq_base)
105 {
106 extern irq_desc_t irq_desc[];
107 u32 i;
108
109 for (i= irq_base; i< irq_base+ NUM_5477_IRQ; i++) {
110 irq_desc[i].status = IRQ_DISABLED;
111 irq_desc[i].action = NULL;
112 irq_desc[i].depth = 1;
113 irq_desc[i].handler = &vrc5477_irq_controller;
114 }
115
116 vrc5477_irq_base = irq_base;
117 }
118
ll_vrc5477_irq_route(int vrc5477_irq,int ip)119 void ll_vrc5477_irq_route(int vrc5477_irq, int ip)
120 {
121 u32 reg_value;
122 u32 reg_bitmask;
123 u32 reg_index;
124
125 db_assert(vrc5477_irq >= 0);
126 db_assert(vrc5477_irq < NUM_5477_IRQ);
127 db_assert(ip >= 0);
128 db_assert((ip < 5) || (ip == 6));
129
130 reg_index = DDB_INTCTRL0 + vrc5477_irq/8*4;
131 reg_value = ddb_in32(reg_index);
132 reg_bitmask = 7 << (vrc5477_irq % 8 * 4);
133 reg_value &= ~reg_bitmask;
134 reg_value |= ip << (vrc5477_irq % 8 * 4);
135 ddb_out32(reg_index, reg_value);
136 }
137
ll_vrc5477_irq_enable(int vrc5477_irq)138 void ll_vrc5477_irq_enable(int vrc5477_irq)
139 {
140 u32 reg_value;
141 u32 reg_bitmask;
142 u32 reg_index;
143
144 db_assert(vrc5477_irq >= 0);
145 db_assert(vrc5477_irq < NUM_5477_IRQ);
146
147 reg_index = DDB_INTCTRL0 + vrc5477_irq/8*4;
148 reg_value = ddb_in32(reg_index);
149 reg_bitmask = 8 << (vrc5477_irq % 8 * 4);
150 db_assert((reg_value & reg_bitmask) == 0);
151 ddb_out32(reg_index, reg_value | reg_bitmask);
152 }
153
ll_vrc5477_irq_disable(int vrc5477_irq)154 void ll_vrc5477_irq_disable(int vrc5477_irq)
155 {
156 u32 reg_value;
157 u32 reg_bitmask;
158 u32 reg_index;
159
160 db_assert(vrc5477_irq >= 0);
161 db_assert(vrc5477_irq < NUM_5477_IRQ);
162
163 reg_index = DDB_INTCTRL0 + vrc5477_irq/8*4;
164 reg_value = ddb_in32(reg_index);
165 reg_bitmask = 8 << (vrc5477_irq % 8 * 4);
166
167 /* we assert that the interrupt is enabled (perhaps over-zealous) */
168 db_assert( (reg_value & reg_bitmask) != 0);
169 ddb_out32(reg_index, reg_value & ~reg_bitmask);
170 }
171