summaryrefslogtreecommitdiffstats
path: root/arch/avr32/mach-at32ap/extint.c
blob: 7da9c5f7a0eb8cfd14419c0ff57b9ddcfd28b7b0 (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
170
171
/*
 * External interrupt handling for AT32AP CPUs
 *
 * Copyright (C) 2006 Atmel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/platform_device.h>
#include <linux/random.h>

#include <asm/io.h>

#include <asm/arch/sm.h>

#include "sm.h"

static void eim_ack_irq(unsigned int irq)
{
	struct at32_sm *sm = get_irq_chip_data(irq);
	sm_writel(sm, EIM_ICR, 1 << (irq - sm->eim_first_irq));
}

static void eim_mask_irq(unsigned int irq)
{
	struct at32_sm *sm = get_irq_chip_data(irq);
	sm_writel(sm, EIM_IDR, 1 << (irq - sm->eim_first_irq));
}

static void eim_mask_ack_irq(unsigned int irq)
{
	struct at32_sm *sm = get_irq_chip_data(irq);
	sm_writel(sm, EIM_ICR, 1 << (irq - sm->eim_first_irq));
	sm_writel(sm, EIM_IDR, 1 << (irq - sm->eim_first_irq));
}

static void eim_unmask_irq(unsigned int irq)
{
	struct at32_sm *sm = get_irq_chip_data(irq);
	sm_writel(sm, EIM_IER, 1 << (irq - sm->eim_first_irq));
}

static int eim_set_irq_type(unsigned int irq, unsigned int flow_type)
{
	struct at32_sm *sm = get_irq_chip_data(irq);
	unsigned int i = irq - sm->eim_first_irq;
	u32 mode, edge, level;
	unsigned long flags;
	int ret = 0;

	flow_type &= IRQ_TYPE_SENSE_MASK;

	spin_lock_irqsave(&sm->lock, flags);

	mode = sm_readl(sm, EIM_MODE);
	edge = sm_readl(sm, EIM_EDGE);
	level = sm_readl(sm, EIM_LEVEL);

	switch (flow_type) {
	case IRQ_TYPE_LEVEL_LOW:
		mode |= 1 << i;
		level &= ~(1 << i);
		break;
	case IRQ_TYPE_LEVEL_HIGH:
		mode |= 1 << i;
		level |= 1 << i;
		break;
	case IRQ_TYPE_EDGE_RISING:
		mode &= ~(1 << i);
		edge |= 1 << i;
		break;
	case IRQ_TYPE_EDGE_FALLING:
		mode &= ~(1 << i);
		edge &= ~(1 << i);
		break;
	default:
		ret = -EINVAL;
		break;
	}

	sm_writel(sm, EIM_MODE, mode);
	sm_writel(sm, EIM_EDGE, edge);
	sm_writel(sm, EIM_LEVEL, level);

	spin_unlock_irqrestore(&sm->lock, flags);

	return ret;
}

struct irq_chip eim_chip = {
	.name		= "eim",
	.ack		= eim_ack_irq,
	.mask		= eim_mask_irq,
	.mask_ack	= eim_mask_ack_irq,
	.unmask		= eim_unmask_irq,
	.set_type	= eim_set_irq_type,
};

static void demux_eim_irq(unsigned int irq, struct irq_desc *desc,
			  struct pt_regs *regs)
{
	struct at32_sm *sm = desc->handler_data;
	struct irq_desc *ext_desc;
	unsigned long status, pending;
	unsigned int i, ext_irq;

	spin_lock(&sm->lock);

	status = sm_readl(sm, EIM_ISR);
	pending = status & sm_readl(sm, EIM_IMR);

	while (pending) {
		i = fls(pending) - 1;
		pending &= ~(1 << i);

		ext_irq = i + sm->eim_first_irq;
		ext_desc = irq_desc + ext_irq;
		ext_desc->handle_irq(ext_irq, ext_desc, regs);
	}

	spin_unlock(&sm->lock);
}

static int __init eim_init(void)
{
	struct at32_sm *sm = &system_manager;
	unsigned int i;
	unsigned int nr_irqs;
	unsigned int int_irq;
	u32 pattern;

	/*
	 * The EIM is really the same module as SM, so register
	 * mapping, etc. has been taken care of already.
	 */

	/*
	 * Find out how many interrupt lines that are actually
	 * implemented in hardware.
	 */
	sm_writel(sm, EIM_IDR, ~0UL);
	sm_writel(sm, EIM_MODE, ~0UL);
	pattern = sm_readl(sm, EIM_MODE);
	nr_irqs = fls(pattern);

	sm->eim_chip = &eim_chip;

	for (i = 0; i < nr_irqs; i++) {
		set_irq_chip(sm->eim_first_irq + i, &eim_chip);
		set_irq_chip_data(sm->eim_first_irq + i, sm);
	}

	int_irq = platform_get_irq_byname(sm->pdev, "eim");

	set_irq_chained_handler(int_irq, demux_eim_irq);
	set_irq_data(int_irq, sm);

	printk("EIM: External Interrupt Module at 0x%p, IRQ %u\n",
	       sm->regs, int_irq);
	printk("EIM: Handling %u external IRQs, starting with IRQ %u\n",
	       nr_irqs, sm->eim_first_irq);

	return 0;
}
arch_initcall(eim_init);