summaryrefslogtreecommitdiffstats
path: root/drivers/irqchip/irq-orion.c
blob: 0dfdc5c824a124ca36442ddea2d4befa0467a921 (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
/*
 * Marvell Orion SoCs IRQ chip driver.
 *
 * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <asm/exception.h>
#include <asm/mach/irq.h>

#include "irqchip.h"

/*
 * Orion SoC main interrupt controller
 */
#define ORION_IRQS_PER_CHIP		32

#define ORION_IRQ_CAUSE			0x00
#define ORION_IRQ_MASK			0x04
#define ORION_IRQ_FIQ_MASK		0x08
#define ORION_IRQ_ENDP_MASK		0x0c

static struct irq_domain *orion_irq_domain;

static asmlinkage void
__exception_irq_entry orion_handle_irq(struct pt_regs *regs)
{
	struct irq_domain_chip_generic *dgc = orion_irq_domain->gc;
	int n, base = 0;

	for (n = 0; n < dgc->num_chips; n++, base += ORION_IRQS_PER_CHIP) {
		struct irq_chip_generic *gc =
			irq_get_domain_generic_chip(orion_irq_domain, base);
		u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) &
			gc->mask_cache;
		while (stat) {
			u32 hwirq = ffs(stat) - 1;
			u32 irq = irq_find_mapping(orion_irq_domain,
						   gc->irq_base + hwirq);
			handle_IRQ(irq, regs);
			stat &= ~(1 << hwirq);
		}
	}
}

static int __init orion_irq_init(struct device_node *np,
				 struct device_node *parent)
{
	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
	int n, ret, base, num_chips = 0;
	struct resource r;

	/* count number of irq chips by valid reg addresses */
	while (of_address_to_resource(np, num_chips, &r) == 0)
		num_chips++;

	orion_irq_domain = irq_domain_add_linear(np,
				num_chips * ORION_IRQS_PER_CHIP,
				&irq_generic_chip_ops, NULL);
	if (!orion_irq_domain)
		panic("%s: unable to add irq domain\n", np->name);

	ret = irq_alloc_domain_generic_chips(orion_irq_domain,
				ORION_IRQS_PER_CHIP, 1, np->name,
				handle_level_irq, clr, 0,
				IRQ_GC_INIT_MASK_CACHE);
	if (ret)
		panic("%s: unable to alloc irq domain gc\n", np->name);

	for (n = 0, base = 0; n < num_chips; n++, base += ORION_IRQS_PER_CHIP) {
		struct irq_chip_generic *gc =
			irq_get_domain_generic_chip(orion_irq_domain, base);

		of_address_to_resource(np, n, &r);

		if (!request_mem_region(r.start, resource_size(&r), np->name))
			panic("%s: unable to request mem region %d",
			      np->name, n);

		gc->reg_base = ioremap(r.start, resource_size(&r));
		if (!gc->reg_base)
			panic("%s: unable to map resource %d", np->name, n);

		gc->chip_types[0].regs.mask = ORION_IRQ_MASK;
		gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
		gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;

		/* mask all interrupts */
		writel(0, gc->reg_base + ORION_IRQ_MASK);
	}

	set_handle_irq(orion_handle_irq);
	return 0;
}
IRQCHIP_DECLARE(orion_intc, "marvell,orion-intc", orion_irq_init);

/*
 * Orion SoC bridge interrupt controller
 */
#define ORION_BRIDGE_IRQ_CAUSE	0x00
#define ORION_BRIDGE_IRQ_MASK	0x04

static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc)
{
	struct irq_domain *d = irq_get_handler_data(irq);
	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, irq);
	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
		   gc->mask_cache;

	while (stat) {
		u32 hwirq = ffs(stat) - 1;

		generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq));
		stat &= ~(1 << hwirq);
	}
}

/*
 * Bridge IRQ_CAUSE is asserted regardless of IRQ_MASK register.
 * To avoid interrupt events on stale irqs, we clear them before unmask.
 */
static unsigned int orion_bridge_irq_startup(struct irq_data *d)
{
	struct irq_chip_type *ct = irq_data_get_chip_type(d);

	ct->chip.irq_ack(d);
	ct->chip.irq_unmask(d);
	return 0;
}

static int __init orion_bridge_irq_init(struct device_node *np,
					struct device_node *parent)
{
	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
	struct resource r;
	struct irq_domain *domain;
	struct irq_chip_generic *gc;
	int ret, irq, nrirqs = 32;

	/* get optional number of interrupts provided */
	of_property_read_u32(np, "marvell,#interrupts", &nrirqs);

	domain = irq_domain_add_linear(np, nrirqs,
				       &irq_generic_chip_ops, NULL);
	if (!domain) {
		pr_err("%s: unable to add irq domain\n", np->name);
		return -ENOMEM;
	}

	ret = irq_alloc_domain_generic_chips(domain, nrirqs, 1, np->name,
			     handle_edge_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE);
	if (ret) {
		pr_err("%s: unable to alloc irq domain gc\n", np->name);
		return ret;
	}

	ret = of_address_to_resource(np, 0, &r);
	if (ret) {
		pr_err("%s: unable to get resource\n", np->name);
		return ret;
	}

	if (!request_mem_region(r.start, resource_size(&r), np->name)) {
		pr_err("%s: unable to request mem region\n", np->name);
		return -ENOMEM;
	}

	/* Map the parent interrupt for the chained handler */
	irq = irq_of_parse_and_map(np, 0);
	if (irq <= 0) {
		pr_err("%s: unable to parse irq\n", np->name);
		return -EINVAL;
	}

	gc = irq_get_domain_generic_chip(domain, 0);
	gc->reg_base = ioremap(r.start, resource_size(&r));
	if (!gc->reg_base) {
		pr_err("%s: unable to map resource\n", np->name);
		return -ENOMEM;
	}

	gc->chip_types[0].regs.ack = ORION_BRIDGE_IRQ_CAUSE;
	gc->chip_types[0].regs.mask = ORION_BRIDGE_IRQ_MASK;
	gc->chip_types[0].chip.irq_startup = orion_bridge_irq_startup;
	gc->chip_types[0].chip.irq_ack = irq_gc_ack_clr_bit;
	gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;

	/* mask and clear all interrupts */
	writel(0, gc->reg_base + ORION_BRIDGE_IRQ_MASK);
	writel(0, gc->reg_base + ORION_BRIDGE_IRQ_CAUSE);

	irq_set_handler_data(irq, domain);
	irq_set_chained_handler(irq, orion_bridge_irq_handler);

	return 0;
}
IRQCHIP_DECLARE(orion_bridge_intc,
		"marvell,orion-bridge-intc", orion_bridge_irq_init);