[go: nahoru, domu]

1/*
2 * Marvell Orion SoCs IRQ chip driver.
3 *
4 * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
5 *
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2.  This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
9 */
10
11#include <linux/io.h>
12#include <linux/irq.h>
13#include <linux/of.h>
14#include <linux/of_address.h>
15#include <linux/of_irq.h>
16#include <asm/exception.h>
17#include <asm/mach/irq.h>
18
19#include "irqchip.h"
20
21/*
22 * Orion SoC main interrupt controller
23 */
24#define ORION_IRQS_PER_CHIP		32
25
26#define ORION_IRQ_CAUSE			0x00
27#define ORION_IRQ_MASK			0x04
28#define ORION_IRQ_FIQ_MASK		0x08
29#define ORION_IRQ_ENDP_MASK		0x0c
30
31static struct irq_domain *orion_irq_domain;
32
33static void
34__exception_irq_entry orion_handle_irq(struct pt_regs *regs)
35{
36	struct irq_domain_chip_generic *dgc = orion_irq_domain->gc;
37	int n, base = 0;
38
39	for (n = 0; n < dgc->num_chips; n++, base += ORION_IRQS_PER_CHIP) {
40		struct irq_chip_generic *gc =
41			irq_get_domain_generic_chip(orion_irq_domain, base);
42		u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) &
43			gc->mask_cache;
44		while (stat) {
45			u32 hwirq = __fls(stat);
46			handle_domain_irq(orion_irq_domain,
47					  gc->irq_base + hwirq, regs);
48			stat &= ~(1 << hwirq);
49		}
50	}
51}
52
53static int __init orion_irq_init(struct device_node *np,
54				 struct device_node *parent)
55{
56	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
57	int n, ret, base, num_chips = 0;
58	struct resource r;
59
60	/* count number of irq chips by valid reg addresses */
61	while (of_address_to_resource(np, num_chips, &r) == 0)
62		num_chips++;
63
64	orion_irq_domain = irq_domain_add_linear(np,
65				num_chips * ORION_IRQS_PER_CHIP,
66				&irq_generic_chip_ops, NULL);
67	if (!orion_irq_domain)
68		panic("%s: unable to add irq domain\n", np->name);
69
70	ret = irq_alloc_domain_generic_chips(orion_irq_domain,
71				ORION_IRQS_PER_CHIP, 1, np->name,
72				handle_level_irq, clr, 0,
73				IRQ_GC_INIT_MASK_CACHE);
74	if (ret)
75		panic("%s: unable to alloc irq domain gc\n", np->name);
76
77	for (n = 0, base = 0; n < num_chips; n++, base += ORION_IRQS_PER_CHIP) {
78		struct irq_chip_generic *gc =
79			irq_get_domain_generic_chip(orion_irq_domain, base);
80
81		of_address_to_resource(np, n, &r);
82
83		if (!request_mem_region(r.start, resource_size(&r), np->name))
84			panic("%s: unable to request mem region %d",
85			      np->name, n);
86
87		gc->reg_base = ioremap(r.start, resource_size(&r));
88		if (!gc->reg_base)
89			panic("%s: unable to map resource %d", np->name, n);
90
91		gc->chip_types[0].regs.mask = ORION_IRQ_MASK;
92		gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
93		gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
94
95		/* mask all interrupts */
96		writel(0, gc->reg_base + ORION_IRQ_MASK);
97	}
98
99	set_handle_irq(orion_handle_irq);
100	return 0;
101}
102IRQCHIP_DECLARE(orion_intc, "marvell,orion-intc", orion_irq_init);
103
104/*
105 * Orion SoC bridge interrupt controller
106 */
107#define ORION_BRIDGE_IRQ_CAUSE	0x00
108#define ORION_BRIDGE_IRQ_MASK	0x04
109
110static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc)
111{
112	struct irq_domain *d = irq_get_handler_data(irq);
113
114	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, 0);
115	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
116		   gc->mask_cache;
117
118	while (stat) {
119		u32 hwirq = __fls(stat);
120
121		generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq));
122		stat &= ~(1 << hwirq);
123	}
124}
125
126/*
127 * Bridge IRQ_CAUSE is asserted regardless of IRQ_MASK register.
128 * To avoid interrupt events on stale irqs, we clear them before unmask.
129 */
130static unsigned int orion_bridge_irq_startup(struct irq_data *d)
131{
132	struct irq_chip_type *ct = irq_data_get_chip_type(d);
133
134	ct->chip.irq_ack(d);
135	ct->chip.irq_unmask(d);
136	return 0;
137}
138
139static int __init orion_bridge_irq_init(struct device_node *np,
140					struct device_node *parent)
141{
142	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
143	struct resource r;
144	struct irq_domain *domain;
145	struct irq_chip_generic *gc;
146	int ret, irq, nrirqs = 32;
147
148	/* get optional number of interrupts provided */
149	of_property_read_u32(np, "marvell,#interrupts", &nrirqs);
150
151	domain = irq_domain_add_linear(np, nrirqs,
152				       &irq_generic_chip_ops, NULL);
153	if (!domain) {
154		pr_err("%s: unable to add irq domain\n", np->name);
155		return -ENOMEM;
156	}
157
158	ret = irq_alloc_domain_generic_chips(domain, nrirqs, 1, np->name,
159			     handle_edge_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE);
160	if (ret) {
161		pr_err("%s: unable to alloc irq domain gc\n", np->name);
162		return ret;
163	}
164
165	ret = of_address_to_resource(np, 0, &r);
166	if (ret) {
167		pr_err("%s: unable to get resource\n", np->name);
168		return ret;
169	}
170
171	if (!request_mem_region(r.start, resource_size(&r), np->name)) {
172		pr_err("%s: unable to request mem region\n", np->name);
173		return -ENOMEM;
174	}
175
176	/* Map the parent interrupt for the chained handler */
177	irq = irq_of_parse_and_map(np, 0);
178	if (irq <= 0) {
179		pr_err("%s: unable to parse irq\n", np->name);
180		return -EINVAL;
181	}
182
183	gc = irq_get_domain_generic_chip(domain, 0);
184	gc->reg_base = ioremap(r.start, resource_size(&r));
185	if (!gc->reg_base) {
186		pr_err("%s: unable to map resource\n", np->name);
187		return -ENOMEM;
188	}
189
190	gc->chip_types[0].regs.ack = ORION_BRIDGE_IRQ_CAUSE;
191	gc->chip_types[0].regs.mask = ORION_BRIDGE_IRQ_MASK;
192	gc->chip_types[0].chip.irq_startup = orion_bridge_irq_startup;
193	gc->chip_types[0].chip.irq_ack = irq_gc_ack_clr_bit;
194	gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
195	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
196
197	/* mask and clear all interrupts */
198	writel(0, gc->reg_base + ORION_BRIDGE_IRQ_MASK);
199	writel(0, gc->reg_base + ORION_BRIDGE_IRQ_CAUSE);
200
201	irq_set_handler_data(irq, domain);
202	irq_set_chained_handler(irq, orion_bridge_irq_handler);
203
204	return 0;
205}
206IRQCHIP_DECLARE(orion_bridge_intc,
207		"marvell,orion-bridge-intc", orion_bridge_irq_init);
208