xref: /linux/drivers/irqchip/irq-orion.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 
31 static struct irq_domain *orion_irq_domain;
32 
33 static asmlinkage 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 = ffs(stat) - 1;
46 			u32 irq = irq_find_mapping(orion_irq_domain,
47 						   gc->irq_base + hwirq);
48 			handle_IRQ(irq, regs);
49 			stat &= ~(1 << hwirq);
50 		}
51 	}
52 }
53 
54 static int __init orion_irq_init(struct device_node *np,
55 				 struct device_node *parent)
56 {
57 	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
58 	int n, ret, base, num_chips = 0;
59 	struct resource r;
60 
61 	/* count number of irq chips by valid reg addresses */
62 	while (of_address_to_resource(np, num_chips, &r) == 0)
63 		num_chips++;
64 
65 	orion_irq_domain = irq_domain_add_linear(np,
66 				num_chips * ORION_IRQS_PER_CHIP,
67 				&irq_generic_chip_ops, NULL);
68 	if (!orion_irq_domain)
69 		panic("%s: unable to add irq domain\n", np->name);
70 
71 	ret = irq_alloc_domain_generic_chips(orion_irq_domain,
72 				ORION_IRQS_PER_CHIP, 1, np->name,
73 				handle_level_irq, clr, 0,
74 				IRQ_GC_INIT_MASK_CACHE);
75 	if (ret)
76 		panic("%s: unable to alloc irq domain gc\n", np->name);
77 
78 	for (n = 0, base = 0; n < num_chips; n++, base += ORION_IRQS_PER_CHIP) {
79 		struct irq_chip_generic *gc =
80 			irq_get_domain_generic_chip(orion_irq_domain, base);
81 
82 		of_address_to_resource(np, n, &r);
83 
84 		if (!request_mem_region(r.start, resource_size(&r), np->name))
85 			panic("%s: unable to request mem region %d",
86 			      np->name, n);
87 
88 		gc->reg_base = ioremap(r.start, resource_size(&r));
89 		if (!gc->reg_base)
90 			panic("%s: unable to map resource %d", np->name, n);
91 
92 		gc->chip_types[0].regs.mask = ORION_IRQ_MASK;
93 		gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
94 		gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
95 
96 		/* mask all interrupts */
97 		writel(0, gc->reg_base + ORION_IRQ_MASK);
98 	}
99 
100 	set_handle_irq(orion_handle_irq);
101 	return 0;
102 }
103 IRQCHIP_DECLARE(orion_intc, "marvell,orion-intc", orion_irq_init);
104 
105 /*
106  * Orion SoC bridge interrupt controller
107  */
108 #define ORION_BRIDGE_IRQ_CAUSE	0x00
109 #define ORION_BRIDGE_IRQ_MASK	0x04
110 
111 static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc)
112 {
113 	struct irq_domain *d = irq_get_handler_data(irq);
114 	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, irq);
115 	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
116 		   gc->mask_cache;
117 
118 	while (stat) {
119 		u32 hwirq = ffs(stat) - 1;
120 
121 		generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq));
122 		stat &= ~(1 << hwirq);
123 	}
124 }
125 
126 static int __init orion_bridge_irq_init(struct device_node *np,
127 					struct device_node *parent)
128 {
129 	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
130 	struct resource r;
131 	struct irq_domain *domain;
132 	struct irq_chip_generic *gc;
133 	int ret, irq, nrirqs = 32;
134 
135 	/* get optional number of interrupts provided */
136 	of_property_read_u32(np, "marvell,#interrupts", &nrirqs);
137 
138 	domain = irq_domain_add_linear(np, nrirqs,
139 				       &irq_generic_chip_ops, NULL);
140 	if (!domain) {
141 		pr_err("%s: unable to add irq domain\n", np->name);
142 		return -ENOMEM;
143 	}
144 
145 	ret = irq_alloc_domain_generic_chips(domain, nrirqs, 1, np->name,
146 			     handle_level_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE);
147 	if (ret) {
148 		pr_err("%s: unable to alloc irq domain gc\n", np->name);
149 		return ret;
150 	}
151 
152 	ret = of_address_to_resource(np, 0, &r);
153 	if (ret) {
154 		pr_err("%s: unable to get resource\n", np->name);
155 		return ret;
156 	}
157 
158 	if (!request_mem_region(r.start, resource_size(&r), np->name)) {
159 		pr_err("%s: unable to request mem region\n", np->name);
160 		return -ENOMEM;
161 	}
162 
163 	/* Map the parent interrupt for the chained handler */
164 	irq = irq_of_parse_and_map(np, 0);
165 	if (irq <= 0) {
166 		pr_err("%s: unable to parse irq\n", np->name);
167 		return -EINVAL;
168 	}
169 
170 	gc = irq_get_domain_generic_chip(domain, 0);
171 	gc->reg_base = ioremap(r.start, resource_size(&r));
172 	if (!gc->reg_base) {
173 		pr_err("%s: unable to map resource\n", np->name);
174 		return -ENOMEM;
175 	}
176 
177 	gc->chip_types[0].regs.ack = ORION_BRIDGE_IRQ_CAUSE;
178 	gc->chip_types[0].regs.mask = ORION_BRIDGE_IRQ_MASK;
179 	gc->chip_types[0].chip.irq_ack = irq_gc_ack_clr_bit;
180 	gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
181 	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
182 
183 	/* mask all interrupts */
184 	writel(0, gc->reg_base + ORION_BRIDGE_IRQ_MASK);
185 
186 	irq_set_handler_data(irq, domain);
187 	irq_set_chained_handler(irq, orion_bridge_irq_handler);
188 
189 	return 0;
190 }
191 IRQCHIP_DECLARE(orion_bridge_intc,
192 		"marvell,orion-bridge-intc", orion_bridge_irq_init);
193