summaryrefslogtreecommitdiff
path: root/arch/mips/jazz/irq.c
blob: d5bd6b3a09335b5bdfbe6fda8b60df2de0bdc24d (plain)
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
/*
 * 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.
 *
 * Copyright (C) 1992 Linus Torvalds
 * Copyright (C) 1994 - 2001, 2003 Ralf Baechle
 */
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>

#include <asm/i8259.h>
#include <asm/io.h>
#include <asm/jazz.h>

static DEFINE_SPINLOCK(r4030_lock);

static void enable_r4030_irq(unsigned int irq)
{
	unsigned int mask = 1 << (irq - JAZZ_PARALLEL_IRQ);
	unsigned long flags;

	spin_lock_irqsave(&r4030_lock, flags);
	mask |= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
	spin_unlock_irqrestore(&r4030_lock, flags);
}

static unsigned int startup_r4030_irq(unsigned int irq)
{
	enable_r4030_irq(irq);
	return 0; /* never anything pending */
}

#define shutdown_r4030_irq	disable_r4030_irq

void disable_r4030_irq(unsigned int irq)
{
	unsigned int mask = ~(1 << (irq - JAZZ_PARALLEL_IRQ));
	unsigned long flags;

	spin_lock_irqsave(&r4030_lock, flags);
	mask &= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
	spin_unlock_irqrestore(&r4030_lock, flags);
}

#define mask_and_ack_r4030_irq disable_r4030_irq

static void end_r4030_irq(unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
		enable_r4030_irq(irq);
}

static struct irq_chip r4030_irq_type = {
	.typename = "R4030",
	.startup = startup_r4030_irq,
	.shutdown = shutdown_r4030_irq,
	.enable = enable_r4030_irq,
	.disable = disable_r4030_irq,
	.ack = mask_and_ack_r4030_irq,
	.end = end_r4030_irq,
};

void __init init_r4030_ints(void)
{
	int i;

	for (i = JAZZ_PARALLEL_IRQ; i <= JAZZ_TIMER_IRQ; i++) {
		irq_desc[i].status     = IRQ_DISABLED;
		irq_desc[i].action     = 0;
		irq_desc[i].depth      = 1;
		irq_desc[i].chip    = &r4030_irq_type;
	}

	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, 0);
	r4030_read_reg16(JAZZ_IO_IRQ_SOURCE);		/* clear pending IRQs */
	r4030_read_reg32(JAZZ_R4030_INVAL_ADDR);	/* clear error bits */
}

/*
 * On systems with i8259-style interrupt controllers we assume for
 * driver compatibility reasons interrupts 0 - 15 to be the i8259
 * interrupts even if the hardware uses a different interrupt numbering.
 */
void __init arch_init_irq(void)
{
	init_i8259_irqs();			/* Integrated i8259  */
	init_r4030_ints();

	change_c0_status(ST0_IM, IE_IRQ4 | IE_IRQ3 | IE_IRQ2 | IE_IRQ1);
}

static void loc_call(unsigned int irq, unsigned int mask)
{
	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE,
	                  r4030_read_reg16(JAZZ_IO_IRQ_ENABLE) & mask);
	do_IRQ(irq);
	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE,
	                  r4030_read_reg16(JAZZ_IO_IRQ_ENABLE) | mask);
}

static void ll_local_dev(void)
{
	switch (r4030_read_reg32(JAZZ_IO_IRQ_SOURCE)) {
	case 0:
		panic("Unimplemented loc_no_irq handler");
		break;
	case 4:
		loc_call(JAZZ_PARALLEL_IRQ, JAZZ_IE_PARALLEL);
		break;
	case 8:
		loc_call(JAZZ_PARALLEL_IRQ, JAZZ_IE_FLOPPY);
		break;
	case 12:
		panic("Unimplemented loc_sound handler");
		break;
	case 16:
		panic("Unimplemented loc_video handler");
		break;
	case 20:
		loc_call(JAZZ_ETHERNET_IRQ, JAZZ_IE_ETHERNET);
		break;
	case 24:
		loc_call(JAZZ_SCSI_IRQ, JAZZ_IE_SCSI);
		break;
	case 28:
		loc_call(JAZZ_KEYBOARD_IRQ, JAZZ_IE_KEYBOARD);
		break;
	case 32:
		loc_call(JAZZ_MOUSE_IRQ, JAZZ_IE_MOUSE);
		break;
	case 36:
		loc_call(JAZZ_SERIAL1_IRQ, JAZZ_IE_SERIAL1);
		break;
	case 40:
		loc_call(JAZZ_SERIAL2_IRQ, JAZZ_IE_SERIAL2);
		break;
	}
}

asmlinkage void plat_irq_dispatch(void)
{
	unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;

	if (pending & IE_IRQ5)
		write_c0_compare(0);
	else if (pending & IE_IRQ4) {
		r4030_read_reg32(JAZZ_TIMER_REGISTER);
		do_IRQ(JAZZ_TIMER_IRQ);
	} else if (pending & IE_IRQ3)
		panic("Unimplemented ISA NMI handler");
	else if (pending & IE_IRQ2)
		do_IRQ(r4030_read_reg32(JAZZ_EISA_IRQ_ACK));
	else if (pending & IE_IRQ1) {
		ll_local_dev();
	} else if (unlikely(pending & IE_IRQ0))
		panic("Unimplemented local_dma handler");
	else if (pending & IE_SW1) {
		clear_c0_cause(IE_SW1);
		panic("Unimplemented sw1 handler");
	} else if (pending & IE_SW0) {
		clear_c0_cause(IE_SW0);
		panic("Unimplemented sw0 handler");
	}
}