summaryrefslogtreecommitdiffstats
path: root/arch/mips/kernel/irq-mv6434x.c
blob: 37d106202b83a7695cb0614013693bb57d5a2bbd (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
/*
 * Copyright 2002 Momentum Computer
 * Author: mdharm@momenco.com
 * Copyright (C) 2004, 06 Ralf Baechle <ralf@linux-mips.org>
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/mv643xx.h>
#include <linux/sched.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/marvell.h>

static unsigned int irq_base;

static inline int ls1bit32(unsigned int x)
{
        int b = 31, s;

        s = 16; if (x << 16 == 0) s = 0; b -= s; x <<= s;
        s =  8; if (x <<  8 == 0) s = 0; b -= s; x <<= s;
        s =  4; if (x <<  4 == 0) s = 0; b -= s; x <<= s;
        s =  2; if (x <<  2 == 0) s = 0; b -= s; x <<= s;
        s =  1; if (x <<  1 == 0) s = 0; b -= s;

        return b;
}

/* mask off an interrupt -- 1 is enable, 0 is disable */
static inline void mask_mv64340_irq(unsigned int irq)
{
	uint32_t value;

	if (irq < (irq_base + 32)) {
		value = MV_READ(MV64340_INTERRUPT0_MASK_0_LOW);
		value &= ~(1 << (irq - irq_base));
		MV_WRITE(MV64340_INTERRUPT0_MASK_0_LOW, value);
	} else {
		value = MV_READ(MV64340_INTERRUPT0_MASK_0_HIGH);
		value &= ~(1 << (irq - irq_base - 32));
		MV_WRITE(MV64340_INTERRUPT0_MASK_0_HIGH, value);
	}
}

/* unmask an interrupt -- 1 is enable, 0 is disable */
static inline void unmask_mv64340_irq(unsigned int irq)
{
	uint32_t value;

	if (irq < (irq_base + 32)) {
		value = MV_READ(MV64340_INTERRUPT0_MASK_0_LOW);
		value |= 1 << (irq - irq_base);
		MV_WRITE(MV64340_INTERRUPT0_MASK_0_LOW, value);
	} else {
		value = MV_READ(MV64340_INTERRUPT0_MASK_0_HIGH);
		value |= 1 << (irq - irq_base - 32);
		MV_WRITE(MV64340_INTERRUPT0_MASK_0_HIGH, value);
	}
}

/*
 * Enables the IRQ on Marvell Chip
 */
static void enable_mv64340_irq(unsigned int irq)
{
	unmask_mv64340_irq(irq);
}

/*
 * Initialize the IRQ on Marvell Chip
 */
static unsigned int startup_mv64340_irq(unsigned int irq)
{
	unmask_mv64340_irq(irq);
	return 0;
}

/*
 * Disables the IRQ on Marvell Chip
 */
static void disable_mv64340_irq(unsigned int irq)
{
	mask_mv64340_irq(irq);
}

/*
 * Masks and ACKs an IRQ
 */
static void mask_and_ack_mv64340_irq(unsigned int irq)
{
	mask_mv64340_irq(irq);
}

/*
 * End IRQ processing
 */
static void end_mv64340_irq(unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
		unmask_mv64340_irq(irq);
}

/*
 * Interrupt handler for interrupts coming from the Marvell chip.
 * It could be built in ethernet ports etc...
 */
void ll_mv64340_irq(void)
{
	unsigned int irq_src_low, irq_src_high;
 	unsigned int irq_mask_low, irq_mask_high;

	/* read the interrupt status registers */
	irq_mask_low = MV_READ(MV64340_INTERRUPT0_MASK_0_LOW);
	irq_mask_high = MV_READ(MV64340_INTERRUPT0_MASK_0_HIGH);
	irq_src_low = MV_READ(MV64340_MAIN_INTERRUPT_CAUSE_LOW);
	irq_src_high = MV_READ(MV64340_MAIN_INTERRUPT_CAUSE_HIGH);

	/* mask for just the interrupts we want */
	irq_src_low &= irq_mask_low;
	irq_src_high &= irq_mask_high;

	if (irq_src_low)
		do_IRQ(ls1bit32(irq_src_low) + irq_base);
	else
		do_IRQ(ls1bit32(irq_src_high) + irq_base + 32);
}

#define shutdown_mv64340_irq	disable_mv64340_irq

struct irq_chip mv64340_irq_type = {
	.typename = "MV-64340",
	.startup = startup_mv64340_irq,
	.shutdown = shutdown_mv64340_irq,
	.enable = enable_mv64340_irq,
	.disable = disable_mv64340_irq,
	.ack = mask_and_ack_mv64340_irq,
	.end = end_mv64340_irq,
};

void __init mv64340_irq_init(unsigned int base)
{
	int i;

	/* Reset irq handlers pointers to NULL */
	for (i = base; i < base + 64; i++) {
		irq_desc[i].status = IRQ_DISABLED;
		irq_desc[i].action = 0;
		irq_desc[i].depth = 2;
		irq_desc[i].chip = &mv64340_irq_type;
	}

	irq_base = base;
}