summaryrefslogtreecommitdiffstats
path: root/arch/m68k/coldfire/intc.c
blob: b434371e2b99e76e8468627ca19d3880b67e94e2 (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
/*
 * intc.c  -- support for the old ColdFire interrupt controller
 *
 * (C) Copyright 2009, Greg Ungerer <gerg@snapgear.com>
 *
 * 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.
 */

#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <asm/traps.h>
#include <asm/coldfire.h>
#include <asm/mcfsim.h>

/*
 * The mapping of irq number to a mask register bit is not one-to-one.
 * The irq numbers are either based on "level" of interrupt or fixed
 * for an autovector-able interrupt. So we keep a local data structure
 * that maps from irq to mask register. Not all interrupts will have
 * an IMR bit.
 */
unsigned char mcf_irq2imr[NR_IRQS];

/*
 * Define the minimum and maximum external interrupt numbers.
 * This is also used as the "level" interrupt numbers.
 */
#define	EIRQ1	25
#define	EIRQ7	31

/*
 * In the early version 2 core ColdFire parts the IMR register was 16 bits
 * in size. Version 3 (and later version 2) core parts have a 32 bit
 * sized IMR register. Provide some size independent methods to access the
 * IMR register.
 */
#ifdef MCFSIM_IMR_IS_16BITS

void mcf_setimr(int index)
{
	u16 imr;
	imr = __raw_readw(MCFSIM_IMR);
	__raw_writew(imr | (0x1 << index), MCFSIM_IMR);
}

void mcf_clrimr(int index)
{
	u16 imr;
	imr = __raw_readw(MCFSIM_IMR);
	__raw_writew(imr & ~(0x1 << index), MCFSIM_IMR);
}

static void mcf_maskimr(unsigned int mask)
{
	u16 imr;
	imr = __raw_readw(MCFSIM_IMR);
	imr |= mask;
	__raw_writew(imr, MCFSIM_IMR);
}

#else

void mcf_setimr(int index)
{
	u32 imr;
	imr = __raw_readl(MCFSIM_IMR);
	__raw_writel(imr | (0x1 << index), MCFSIM_IMR);
}

void mcf_clrimr(int index)
{
	u32 imr;
	imr = __raw_readl(MCFSIM_IMR);
	__raw_writel(imr & ~(0x1 << index), MCFSIM_IMR);
}

static void mcf_maskimr(unsigned int mask)
{
	u32 imr;
	imr = __raw_readl(MCFSIM_IMR);
	imr |= mask;
	__raw_writel(imr, MCFSIM_IMR);
}

#endif

/*
 * Interrupts can be "vectored" on the ColdFire cores that support this old
 * interrupt controller. That is, the device raising the interrupt can also
 * supply the vector number to interrupt through. The AVR register of the
 * interrupt controller enables or disables this for each external interrupt,
 * so provide generic support for this. Setting this up is out-of-band for
 * the interrupt system API's, and needs to be done by the driver that
 * supports this device. Very few devices actually use this.
 */
void mcf_autovector(int irq)
{
#ifdef MCFSIM_AVR
	if ((irq >= EIRQ1) && (irq <= EIRQ7)) {
		u8 avec;
		avec = __raw_readb(MCFSIM_AVR);
		avec |= (0x1 << (irq - EIRQ1 + 1));
		__raw_writeb(avec, MCFSIM_AVR);
	}
#endif
}

static void intc_irq_mask(struct irq_data *d)
{
	if (mcf_irq2imr[d->irq])
		mcf_setimr(mcf_irq2imr[d->irq]);
}

static void intc_irq_unmask(struct irq_data *d)
{
	if (mcf_irq2imr[d->irq])
		mcf_clrimr(mcf_irq2imr[d->irq]);
}

static int intc_irq_set_type(struct irq_data *d, unsigned int type)
{
	return 0;
}

static struct irq_chip intc_irq_chip = {
	.name		= "CF-INTC",
	.irq_mask	= intc_irq_mask,
	.irq_unmask	= intc_irq_unmask,
	.irq_set_type	= intc_irq_set_type,
};

void __init init_IRQ(void)
{
	int irq;

	mcf_maskimr(0xffffffff);

	for (irq = 0; (irq < NR_IRQS); irq++) {
		irq_set_chip(irq, &intc_irq_chip);
		irq_set_irq_type(irq, IRQ_TYPE_LEVEL_HIGH);
		irq_set_handler(irq, handle_level_irq);
	}
}