summaryrefslogtreecommitdiffstats
path: root/arch/mips/bcm63xx/irq.c
blob: 162e11b4ed755f7e227d4cfc485d40170716abdf (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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
/*
 * 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) 2008 Maxime Bizon <mbizon@freebox.fr>
 * Copyright (C) 2008 Nicolas Schichan <nschichan@freebox.fr>
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/irq.h>
#include <asm/irq_cpu.h>
#include <asm/mipsregs.h>
#include <bcm63xx_cpu.h>
#include <bcm63xx_regs.h>
#include <bcm63xx_io.h>
#include <bcm63xx_irq.h>

/*
 * dispatch internal devices IRQ (uart, enet, watchdog, ...). do not
 * prioritize any interrupt relatively to another. the static counter
 * will resume the loop where it ended the last time we left this
 * function.
 */
static void bcm63xx_irq_dispatch_internal(void)
{
	u32 pending;
	static int i;

	pending = bcm_perf_readl(PERF_IRQMASK_REG) &
		bcm_perf_readl(PERF_IRQSTAT_REG);

	if (!pending)
		return ;

	while (1) {
		int to_call = i;

		i = (i + 1) & 0x1f;
		if (pending & (1 << to_call)) {
			do_IRQ(to_call + IRQ_INTERNAL_BASE);
			break;
		}
	}
}

asmlinkage void plat_irq_dispatch(void)
{
	u32 cause;

	do {
		cause = read_c0_cause() & read_c0_status() & ST0_IM;

		if (!cause)
			break;

		if (cause & CAUSEF_IP7)
			do_IRQ(7);
		if (cause & CAUSEF_IP2)
			bcm63xx_irq_dispatch_internal();
		if (cause & CAUSEF_IP3)
			do_IRQ(IRQ_EXT_0);
		if (cause & CAUSEF_IP4)
			do_IRQ(IRQ_EXT_1);
		if (cause & CAUSEF_IP5)
			do_IRQ(IRQ_EXT_2);
		if (cause & CAUSEF_IP6)
			do_IRQ(IRQ_EXT_3);
	} while (1);
}

/*
 * internal IRQs operations: only mask/unmask on PERF irq mask
 * register.
 */
static inline void bcm63xx_internal_irq_mask(struct irq_data *d)
{
	unsigned int irq = d->irq - IRQ_INTERNAL_BASE;
	u32 mask;

	mask = bcm_perf_readl(PERF_IRQMASK_REG);
	mask &= ~(1 << irq);
	bcm_perf_writel(mask, PERF_IRQMASK_REG);
}

static void bcm63xx_internal_irq_unmask(struct irq_data *d)
{
	unsigned int irq = d->irq - IRQ_INTERNAL_BASE;
	u32 mask;

	mask = bcm_perf_readl(PERF_IRQMASK_REG);
	mask |= (1 << irq);
	bcm_perf_writel(mask, PERF_IRQMASK_REG);
}

/*
 * external IRQs operations: mask/unmask and clear on PERF external
 * irq control register.
 */
static void bcm63xx_external_irq_mask(struct irq_data *d)
{
	unsigned int irq = d->irq - IRQ_EXT_BASE;
	u32 reg;

	reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
	reg &= ~EXTIRQ_CFG_MASK(irq);
	bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
}

static void bcm63xx_external_irq_unmask(struct irq_data *d)
{
	unsigned int irq = d->irq - IRQ_EXT_BASE;
	u32 reg;

	reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
	reg |= EXTIRQ_CFG_MASK(irq);
	bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
}

static void bcm63xx_external_irq_clear(struct irq_data *d)
{
	unsigned int irq = d->irq - IRQ_EXT_BASE;
	u32 reg;

	reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
	reg |= EXTIRQ_CFG_CLEAR(irq);
	bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
}

static unsigned int bcm63xx_external_irq_startup(struct irq_data *d)
{
	set_c0_status(0x100 << (d->irq - IRQ_MIPS_BASE));
	irq_enable_hazard();
	bcm63xx_external_irq_unmask(d);
	return 0;
}

static void bcm63xx_external_irq_shutdown(struct irq_data *d)
{
	bcm63xx_external_irq_mask(d);
	clear_c0_status(0x100 << (d->irq - IRQ_MIPS_BASE));
	irq_disable_hazard();
}

static int bcm63xx_external_irq_set_type(struct irq_data *d,
					 unsigned int flow_type)
{
	unsigned int irq = d->irq - IRQ_EXT_BASE;
	u32 reg;

	flow_type &= IRQ_TYPE_SENSE_MASK;

	if (flow_type == IRQ_TYPE_NONE)
		flow_type = IRQ_TYPE_LEVEL_LOW;

	reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
	switch (flow_type) {
	case IRQ_TYPE_EDGE_BOTH:
		reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
		reg |= EXTIRQ_CFG_BOTHEDGE(irq);
		break;

	case IRQ_TYPE_EDGE_RISING:
		reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
		reg |= EXTIRQ_CFG_SENSE(irq);
		reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
		break;

	case IRQ_TYPE_EDGE_FALLING:
		reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
		reg &= ~EXTIRQ_CFG_SENSE(irq);
		reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
		break;

	case IRQ_TYPE_LEVEL_HIGH:
		reg |= EXTIRQ_CFG_LEVELSENSE(irq);
		reg |= EXTIRQ_CFG_SENSE(irq);
		break;

	case IRQ_TYPE_LEVEL_LOW:
		reg |= EXTIRQ_CFG_LEVELSENSE(irq);
		reg &= ~EXTIRQ_CFG_SENSE(irq);
		break;

	default:
		printk(KERN_ERR "bogus flow type combination given !\n");
		return -EINVAL;
	}
	bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);

	irqd_set_trigger_type(d, flow_type);
	if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
		__irq_set_handler_locked(d->irq, handle_level_irq);
	else
		__irq_set_handler_locked(d->irq, handle_edge_irq);

	return IRQ_SET_MASK_OK_NOCOPY;
}

static struct irq_chip bcm63xx_internal_irq_chip = {
	.name		= "bcm63xx_ipic",
	.irq_mask	= bcm63xx_internal_irq_mask,
	.irq_unmask	= bcm63xx_internal_irq_unmask,
};

static struct irq_chip bcm63xx_external_irq_chip = {
	.name		= "bcm63xx_epic",
	.irq_startup	= bcm63xx_external_irq_startup,
	.irq_shutdown	= bcm63xx_external_irq_shutdown,

	.irq_ack	= bcm63xx_external_irq_clear,

	.irq_mask	= bcm63xx_external_irq_mask,
	.irq_unmask	= bcm63xx_external_irq_unmask,

	.irq_set_type	= bcm63xx_external_irq_set_type,
};

static struct irqaction cpu_ip2_cascade_action = {
	.handler	= no_action,
	.name		= "cascade_ip2",
	.flags		= IRQF_NO_THREAD,
};

void __init arch_init_irq(void)
{
	int i;

	mips_cpu_irq_init();
	for (i = IRQ_INTERNAL_BASE; i < NR_IRQS; ++i)
		irq_set_chip_and_handler(i, &bcm63xx_internal_irq_chip,
					 handle_level_irq);

	for (i = IRQ_EXT_BASE; i < IRQ_EXT_BASE + 4; ++i)
		irq_set_chip_and_handler(i, &bcm63xx_external_irq_chip,
					 handle_edge_irq);

	setup_irq(IRQ_MIPS_BASE + 2, &cpu_ip2_cascade_action);
}
OpenPOWER on IntegriCloud