xref: /linux/drivers/irqchip/irq-tb10x.c (revision c48a7c44a1d02516309015b6134c9bb982e17008)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Abilis Systems interrupt controller driver
4  *
5  * Copyright (C) Abilis Systems 2012
6  *
7  * Author: Christian Ruppert <christian.ruppert@abilis.com>
8  */
9 
10 #include <linux/interrupt.h>
11 #include <linux/irqdomain.h>
12 #include <linux/irq.h>
13 #include <linux/irqchip.h>
14 #include <linux/of_irq.h>
15 #include <linux/of_address.h>
16 #include <linux/io.h>
17 #include <linux/slab.h>
18 #include <linux/bitops.h>
19 
20 #define AB_IRQCTL_INT_ENABLE   0x00
21 #define AB_IRQCTL_INT_STATUS   0x04
22 #define AB_IRQCTL_SRC_MODE     0x08
23 #define AB_IRQCTL_SRC_POLARITY 0x0C
24 #define AB_IRQCTL_INT_MODE     0x10
25 #define AB_IRQCTL_INT_POLARITY 0x14
26 #define AB_IRQCTL_INT_FORCE    0x18
27 
28 #define AB_IRQCTL_MAXIRQ       32
29 
30 static inline void ab_irqctl_writereg(struct irq_chip_generic *gc, u32 reg,
31 	u32 val)
32 {
33 	irq_reg_writel(gc, val, reg);
34 }
35 
36 static inline u32 ab_irqctl_readreg(struct irq_chip_generic *gc, u32 reg)
37 {
38 	return irq_reg_readl(gc, reg);
39 }
40 
41 static int tb10x_irq_set_type(struct irq_data *data, unsigned int flow_type)
42 {
43 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
44 	uint32_t im, mod, pol;
45 
46 	im = data->mask;
47 
48 	irq_gc_lock(gc);
49 
50 	mod = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_MODE) | im;
51 	pol = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_POLARITY) | im;
52 
53 	switch (flow_type & IRQF_TRIGGER_MASK) {
54 	case IRQ_TYPE_EDGE_FALLING:
55 		pol ^= im;
56 		break;
57 	case IRQ_TYPE_LEVEL_HIGH:
58 		mod ^= im;
59 		break;
60 	case IRQ_TYPE_NONE:
61 		flow_type = IRQ_TYPE_LEVEL_LOW;
62 		fallthrough;
63 	case IRQ_TYPE_LEVEL_LOW:
64 		mod ^= im;
65 		pol ^= im;
66 		break;
67 	case IRQ_TYPE_EDGE_RISING:
68 		break;
69 	default:
70 		irq_gc_unlock(gc);
71 		pr_err("%s: Cannot assign multiple trigger modes to IRQ %d.\n",
72 			__func__, data->irq);
73 		return -EBADR;
74 	}
75 
76 	irqd_set_trigger_type(data, flow_type);
77 	irq_setup_alt_chip(data, flow_type);
78 
79 	ab_irqctl_writereg(gc, AB_IRQCTL_SRC_MODE, mod);
80 	ab_irqctl_writereg(gc, AB_IRQCTL_SRC_POLARITY, pol);
81 	ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, im);
82 
83 	irq_gc_unlock(gc);
84 
85 	return IRQ_SET_MASK_OK;
86 }
87 
88 static void tb10x_irq_cascade(struct irq_desc *desc)
89 {
90 	struct irq_domain *domain = irq_desc_get_handler_data(desc);
91 	unsigned int irq = irq_desc_get_irq(desc);
92 
93 	generic_handle_domain_irq(domain, irq);
94 }
95 
96 static int __init of_tb10x_init_irq(struct device_node *ictl,
97 					struct device_node *parent)
98 {
99 	int i, ret, nrirqs = of_irq_count(ictl);
100 	struct resource mem;
101 	struct irq_chip_generic *gc;
102 	struct irq_domain *domain;
103 	void __iomem *reg_base;
104 
105 	if (of_address_to_resource(ictl, 0, &mem)) {
106 		pr_err("%pOFn: No registers declared in DeviceTree.\n",
107 			ictl);
108 		return -EINVAL;
109 	}
110 
111 	if (!request_mem_region(mem.start, resource_size(&mem),
112 		ictl->full_name)) {
113 		pr_err("%pOFn: Request mem region failed.\n", ictl);
114 		return -EBUSY;
115 	}
116 
117 	reg_base = ioremap(mem.start, resource_size(&mem));
118 	if (!reg_base) {
119 		ret = -EBUSY;
120 		pr_err("%pOFn: ioremap failed.\n", ictl);
121 		goto ioremap_fail;
122 	}
123 
124 	domain = irq_domain_add_linear(ictl, AB_IRQCTL_MAXIRQ,
125 					&irq_generic_chip_ops, NULL);
126 	if (!domain) {
127 		ret = -ENOMEM;
128 		pr_err("%pOFn: Could not register interrupt domain.\n",
129 			ictl);
130 		goto irq_domain_add_fail;
131 	}
132 
133 	ret = irq_alloc_domain_generic_chips(domain, AB_IRQCTL_MAXIRQ,
134 				2, ictl->name, handle_level_irq,
135 				IRQ_NOREQUEST, IRQ_NOPROBE,
136 				IRQ_GC_INIT_MASK_CACHE);
137 	if (ret) {
138 		pr_err("%pOFn: Could not allocate generic interrupt chip.\n",
139 			ictl);
140 		goto gc_alloc_fail;
141 	}
142 
143 	gc = domain->gc->gc[0];
144 	gc->reg_base                         = reg_base;
145 
146 	gc->chip_types[0].type               = IRQ_TYPE_LEVEL_MASK;
147 	gc->chip_types[0].chip.irq_mask      = irq_gc_mask_clr_bit;
148 	gc->chip_types[0].chip.irq_unmask    = irq_gc_mask_set_bit;
149 	gc->chip_types[0].chip.irq_set_type  = tb10x_irq_set_type;
150 	gc->chip_types[0].regs.mask          = AB_IRQCTL_INT_ENABLE;
151 
152 	gc->chip_types[1].type               = IRQ_TYPE_EDGE_BOTH;
153 	gc->chip_types[1].chip.name          = gc->chip_types[0].chip.name;
154 	gc->chip_types[1].chip.irq_ack       = irq_gc_ack_set_bit;
155 	gc->chip_types[1].chip.irq_mask      = irq_gc_mask_clr_bit;
156 	gc->chip_types[1].chip.irq_unmask    = irq_gc_mask_set_bit;
157 	gc->chip_types[1].chip.irq_set_type  = tb10x_irq_set_type;
158 	gc->chip_types[1].regs.ack           = AB_IRQCTL_INT_STATUS;
159 	gc->chip_types[1].regs.mask          = AB_IRQCTL_INT_ENABLE;
160 	gc->chip_types[1].handler            = handle_edge_irq;
161 
162 	for (i = 0; i < nrirqs; i++) {
163 		unsigned int irq = irq_of_parse_and_map(ictl, i);
164 
165 		irq_set_chained_handler_and_data(irq, tb10x_irq_cascade,
166 						 domain);
167 	}
168 
169 	ab_irqctl_writereg(gc, AB_IRQCTL_INT_ENABLE, 0);
170 	ab_irqctl_writereg(gc, AB_IRQCTL_INT_MODE, 0);
171 	ab_irqctl_writereg(gc, AB_IRQCTL_INT_POLARITY, 0);
172 	ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, ~0UL);
173 
174 	return 0;
175 
176 gc_alloc_fail:
177 	irq_domain_remove(domain);
178 irq_domain_add_fail:
179 	iounmap(reg_base);
180 ioremap_fail:
181 	release_mem_region(mem.start, resource_size(&mem));
182 	return ret;
183 }
184 IRQCHIP_DECLARE(tb10x_intc, "abilis,tb10x-ictl", of_tb10x_init_irq);
185