summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-at91/irq.c
blob: fc059ec4b0213ff20046811314f7442106a87aea (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
/*
 * linux/arch/arm/mach-at91/irq.c
 *
 *  Copyright (C) 2004 SAN People
 *  Copyright (C) 2004 ATMEL
 *  Copyright (C) Rick Bronson
 *
 * 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.
 *
 * This program is distributed in the hope that 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/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/types.h>

#include <asm/hardware.h>
#include <asm/irq.h>
#include <asm/setup.h>

#include <asm/mach/arch.h>
#include <asm/mach/irq.h>
#include <asm/mach/map.h>


static void at91_aic_mask_irq(unsigned int irq)
{
	/* Disable interrupt on AIC */
	at91_sys_write(AT91_AIC_IDCR, 1 << irq);
}

static void at91_aic_unmask_irq(unsigned int irq)
{
	/* Enable interrupt on AIC */
	at91_sys_write(AT91_AIC_IECR, 1 << irq);
}

unsigned int at91_extern_irq;

#define is_extern_irq(irq) ((1 << (irq)) & at91_extern_irq)

static int at91_aic_set_type(unsigned irq, unsigned type)
{
	unsigned int smr, srctype;

	switch (type) {
	case IRQ_TYPE_LEVEL_HIGH:
		srctype = AT91_AIC_SRCTYPE_HIGH;
		break;
	case IRQ_TYPE_EDGE_RISING:
		srctype = AT91_AIC_SRCTYPE_RISING;
		break;
	case IRQ_TYPE_LEVEL_LOW:
		if ((irq == AT91_ID_FIQ) || is_extern_irq(irq))		/* only supported on external interrupts */
			srctype = AT91_AIC_SRCTYPE_LOW;
		else
			return -EINVAL;
		break;
	case IRQ_TYPE_EDGE_FALLING:
		if ((irq == AT91_ID_FIQ) || is_extern_irq(irq))		/* only supported on external interrupts */
			srctype = AT91_AIC_SRCTYPE_FALLING;
		else
			return -EINVAL;
		break;
	default:
		return -EINVAL;
	}

	smr = at91_sys_read(AT91_AIC_SMR(irq)) & ~AT91_AIC_SRCTYPE;
	at91_sys_write(AT91_AIC_SMR(irq), smr | srctype);
	return 0;
}

#ifdef CONFIG_PM

static u32 wakeups;
static u32 backups;

static int at91_aic_set_wake(unsigned irq, unsigned value)
{
	if (unlikely(irq >= 32))
		return -EINVAL;

	if (value)
		wakeups |= (1 << irq);
	else
		wakeups &= ~(1 << irq);

	return 0;
}

void at91_irq_suspend(void)
{
	backups = at91_sys_read(AT91_AIC_IMR);
	at91_sys_write(AT91_AIC_IDCR, backups);
	at91_sys_write(AT91_AIC_IECR, wakeups);
}

void at91_irq_resume(void)
{
	at91_sys_write(AT91_AIC_IDCR, wakeups);
	at91_sys_write(AT91_AIC_IECR, backups);
}

#else
#define at91_aic_set_wake	NULL
#endif

static struct irq_chip at91_aic_chip = {
	.name		= "AIC",
	.ack		= at91_aic_mask_irq,
	.mask		= at91_aic_mask_irq,
	.unmask		= at91_aic_unmask_irq,
	.set_type	= at91_aic_set_type,
	.set_wake	= at91_aic_set_wake,
};

/*
 * Initialize the AIC interrupt controller.
 */
void __init at91_aic_init(unsigned int priority[NR_AIC_IRQS])
{
	unsigned int i;

	/*
	 * The IVR is used by macro get_irqnr_and_base to read and verify.
	 * The irq number is NR_AIC_IRQS when a spurious interrupt has occurred.
	 */
	for (i = 0; i < NR_AIC_IRQS; i++) {
		/* Put irq number in Source Vector Register: */
		at91_sys_write(AT91_AIC_SVR(i), i);
		/* Active Low interrupt, with the specified priority */
		at91_sys_write(AT91_AIC_SMR(i), AT91_AIC_SRCTYPE_LOW | priority[i]);

		set_irq_chip(i, &at91_aic_chip);
		set_irq_handler(i, handle_level_irq);
		set_irq_flags(i, IRQF_VALID | IRQF_PROBE);

		/* Perform 8 End Of Interrupt Command to make sure AIC will not Lock out nIRQ */
		if (i < 8)
			at91_sys_write(AT91_AIC_EOICR, 0);
	}

	/*
	 * Spurious Interrupt ID in Spurious Vector Register is NR_AIC_IRQS
	 * When there is no current interrupt, the IRQ Vector Register reads the value stored in AIC_SPU
	 */
	at91_sys_write(AT91_AIC_SPU, NR_AIC_IRQS);

	/* No debugging in AIC: Debug (Protect) Control Register */
	at91_sys_write(AT91_AIC_DCR, 0);

	/* Disable and clear all interrupts initially */
	at91_sys_write(AT91_AIC_IDCR, 0xFFFFFFFF);
	at91_sys_write(AT91_AIC_ICCR, 0xFFFFFFFF);
}
OpenPOWER on IntegriCloud