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
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
|
/*
*
* Copyright (C) 2005 Embedded Alley Solutions, Inc
* Ported to 2.6.
*
* Per Hallsmark, per.hallsmark@mvista.com
* Copyright (C) 2000, 2001 MIPS Technologies, Inc.
* Copyright (C) 2001 Ralf Baechle
*
* Cleaned up and bug fixing: Pete Popov, ppopov@embeddedalley.com
*
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
*
* This program is distributed in the hope 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, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
*/
#include <linux/compiler.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/random.h>
#include <linux/module.h>
#include <asm/io.h>
#include <int.h>
#include <uart.h>
/* default prio for interrupts */
/* first one is a no-no so therefore always prio 0 (disabled) */
static char gic_prio[PNX8550_INT_GIC_TOTINT] = {
0, 1, 1, 1, 1, 15, 1, 1, 1, 1, // 0 - 9
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 10 - 19
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 20 - 29
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 30 - 39
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 40 - 49
1, 1, 1, 1, 1, 1, 1, 1, 2, 1, // 50 - 59
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 60 - 69
1 // 70
};
static void hw0_irqdispatch(int irq)
{
/* find out which interrupt */
irq = PNX8550_GIC_VECTOR_0 >> 3;
if (irq == 0) {
printk("hw0_irqdispatch: irq 0, spurious interrupt?\n");
return;
}
do_IRQ(PNX8550_INT_GIC_MIN + irq);
}
static void timer_irqdispatch(int irq)
{
irq = (0x01c0 & read_c0_config7()) >> 6;
if (unlikely(irq == 0)) {
printk("timer_irqdispatch: irq 0, spurious interrupt?\n");
return;
}
if (irq & 0x1)
do_IRQ(PNX8550_INT_TIMER1);
if (irq & 0x2)
do_IRQ(PNX8550_INT_TIMER2);
if (irq & 0x4)
do_IRQ(PNX8550_INT_TIMER3);
}
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM;
if (pending & STATUSF_IP2)
hw0_irqdispatch(2);
else if (pending & STATUSF_IP7) {
if (read_c0_config7() & 0x01c0)
timer_irqdispatch(7);
} else
spurious_interrupt();
}
static inline void modify_cp0_intmask(unsigned clr_mask, unsigned set_mask)
{
unsigned long status = read_c0_status();
status &= ~((clr_mask & 0xFF) << 8);
status |= (set_mask & 0xFF) << 8;
write_c0_status(status);
}
static inline void mask_gic_int(unsigned int irq_nr)
{
/* interrupt disabled, bit 26(WE_ENABLE)=1 and bit 16(enable)=0 */
PNX8550_GIC_REQ(irq_nr) = 1<<28; /* set priority to 0 */
}
static inline void unmask_gic_int(unsigned int irq_nr)
{
/* set prio mask to lower four bits and enable interrupt */
PNX8550_GIC_REQ(irq_nr) = (1<<26 | 1<<16) | (1<<28) | gic_prio[irq_nr];
}
static inline void mask_irq(struct irq_data *d)
{
unsigned int irq_nr = d->irq;
if ((PNX8550_INT_CP0_MIN <= irq_nr) && (irq_nr <= PNX8550_INT_CP0_MAX)) {
modify_cp0_intmask(1 << irq_nr, 0);
} else if ((PNX8550_INT_GIC_MIN <= irq_nr) &&
(irq_nr <= PNX8550_INT_GIC_MAX)) {
mask_gic_int(irq_nr - PNX8550_INT_GIC_MIN);
} else if ((PNX8550_INT_TIMER_MIN <= irq_nr) &&
(irq_nr <= PNX8550_INT_TIMER_MAX)) {
modify_cp0_intmask(1 << 7, 0);
} else {
printk("mask_irq: irq %d doesn't exist!\n", irq_nr);
}
}
static inline void unmask_irq(struct irq_data *d)
{
unsigned int irq_nr = d->irq;
if ((PNX8550_INT_CP0_MIN <= irq_nr) && (irq_nr <= PNX8550_INT_CP0_MAX)) {
modify_cp0_intmask(0, 1 << irq_nr);
} else if ((PNX8550_INT_GIC_MIN <= irq_nr) &&
(irq_nr <= PNX8550_INT_GIC_MAX)) {
unmask_gic_int(irq_nr - PNX8550_INT_GIC_MIN);
} else if ((PNX8550_INT_TIMER_MIN <= irq_nr) &&
(irq_nr <= PNX8550_INT_TIMER_MAX)) {
modify_cp0_intmask(0, 1 << 7);
} else {
printk("mask_irq: irq %d doesn't exist!\n", irq_nr);
}
}
int pnx8550_set_gic_priority(int irq, int priority)
{
int gic_irq = irq-PNX8550_INT_GIC_MIN;
int prev_priority = PNX8550_GIC_REQ(gic_irq) & 0xf;
gic_prio[gic_irq] = priority;
PNX8550_GIC_REQ(gic_irq) |= (0x10000000 | gic_prio[gic_irq]);
return prev_priority;
}
static struct irq_chip level_irq_type = {
.name = "PNX Level IRQ",
.irq_mask = mask_irq,
.irq_unmask = unmask_irq,
};
static struct irqaction gic_action = {
.handler = no_action,
.flags = IRQF_DISABLED | IRQF_NO_THREAD,
.name = "GIC",
};
static struct irqaction timer_action = {
.handler = no_action,
.flags = IRQF_DISABLED | IRQF_TIMER,
.name = "Timer",
};
void __init arch_init_irq(void)
{
int i;
int configPR;
for (i = 0; i < PNX8550_INT_CP0_TOTINT; i++)
irq_set_chip_and_handler(i, &level_irq_type, handle_level_irq);
/* init of GIC/IPC interrupts */
/* should be done before cp0 since cp0 init enables the GIC int */
for (i = PNX8550_INT_GIC_MIN; i <= PNX8550_INT_GIC_MAX; i++) {
int gic_int_line = i - PNX8550_INT_GIC_MIN;
if (gic_int_line == 0 )
continue; // don't fiddle with int 0
/*
* enable change of TARGET, ENABLE and ACTIVE_LOW bits
* set TARGET 0 to route through hw0 interrupt
* set ACTIVE_LOW 0 active high (correct?)
*
* We really should setup an interrupt description table
* to do this nicely.
* Note, PCI INTA is active low on the bus, but inverted
* in the GIC, so to us it's active high.
*/
PNX8550_GIC_REQ(i - PNX8550_INT_GIC_MIN) = 0x1E000000;
/* mask/priority is still 0 so we will not get any
* interrupts until it is unmasked */
irq_set_chip_and_handler(i, &level_irq_type, handle_level_irq);
}
/* Priority level 0 */
PNX8550_GIC_PRIMASK_0 = PNX8550_GIC_PRIMASK_1 = 0;
/* Set int vector table address */
PNX8550_GIC_VECTOR_0 = PNX8550_GIC_VECTOR_1 = 0;
irq_set_chip_and_handler(MIPS_CPU_GIC_IRQ, &level_irq_type,
handle_level_irq);
setup_irq(MIPS_CPU_GIC_IRQ, &gic_action);
/* init of Timer interrupts */
for (i = PNX8550_INT_TIMER_MIN; i <= PNX8550_INT_TIMER_MAX; i++)
irq_set_chip_and_handler(i, &level_irq_type, handle_level_irq);
/* Stop Timer 1-3 */
configPR = read_c0_config7();
configPR |= 0x00000038;
write_c0_config7(configPR);
irq_set_chip_and_handler(MIPS_CPU_TIMER_IRQ, &level_irq_type,
handle_level_irq);
setup_irq(MIPS_CPU_TIMER_IRQ, &timer_action);
}
EXPORT_SYMBOL(pnx8550_set_gic_priority);
|
