1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2014 MediaTek Inc.
4  * Author: Joe.C <yingjoe.chen@mediatek.com>
5  */
6 
7 #include <linux/irq.h>
8 #include <linux/irqchip.h>
9 #include <linux/irqdomain.h>
10 #include <linux/of.h>
11 #include <linux/of_irq.h>
12 #include <linux/of_address.h>
13 #include <linux/io.h>
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16 
17 struct mtk_sysirq_chip_data {
18 	raw_spinlock_t lock;
19 	u32 nr_intpol_bases;
20 	void __iomem **intpol_bases;
21 	u32 *intpol_words;
22 	u8 *intpol_idx;
23 	u16 *which_word;
24 };
25 
26 static int mtk_sysirq_set_type(struct irq_data *data, unsigned int type)
27 {
28 	irq_hw_number_t hwirq = data->hwirq;
29 	struct mtk_sysirq_chip_data *chip_data = data->chip_data;
30 	u8 intpol_idx = chip_data->intpol_idx[hwirq];
31 	void __iomem *base;
32 	u32 offset, reg_index, value;
33 	unsigned long flags;
34 	int ret;
35 
36 	base = chip_data->intpol_bases[intpol_idx];
37 	reg_index = chip_data->which_word[hwirq];
38 	offset = hwirq & 0x1f;
39 
40 	raw_spin_lock_irqsave(&chip_data->lock, flags);
41 	value = readl_relaxed(base + reg_index * 4);
42 	if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_EDGE_FALLING) {
43 		if (type == IRQ_TYPE_LEVEL_LOW)
44 			type = IRQ_TYPE_LEVEL_HIGH;
45 		else
46 			type = IRQ_TYPE_EDGE_RISING;
47 		value |= (1 << offset);
48 	} else {
49 		value &= ~(1 << offset);
50 	}
51 
52 	writel_relaxed(value, base + reg_index * 4);
53 
54 	data = data->parent_data;
55 	ret = data->chip->irq_set_type(data, type);
56 	raw_spin_unlock_irqrestore(&chip_data->lock, flags);
57 	return ret;
58 }
59 
60 static struct irq_chip mtk_sysirq_chip = {
61 	.name			= "MT_SYSIRQ",
62 	.irq_mask		= irq_chip_mask_parent,
63 	.irq_unmask		= irq_chip_unmask_parent,
64 	.irq_eoi		= irq_chip_eoi_parent,
65 	.irq_set_type		= mtk_sysirq_set_type,
66 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
67 	.irq_set_affinity	= irq_chip_set_affinity_parent,
68 };
69 
70 static int mtk_sysirq_domain_translate(struct irq_domain *d,
71 				       struct irq_fwspec *fwspec,
72 				       unsigned long *hwirq,
73 				       unsigned int *type)
74 {
75 	if (is_of_node(fwspec->fwnode)) {
76 		if (fwspec->param_count != 3)
77 			return -EINVAL;
78 
79 		/* No PPI should point to this domain */
80 		if (fwspec->param[0] != 0)
81 			return -EINVAL;
82 
83 		*hwirq = fwspec->param[1];
84 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
85 		return 0;
86 	}
87 
88 	return -EINVAL;
89 }
90 
91 static int mtk_sysirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
92 				   unsigned int nr_irqs, void *arg)
93 {
94 	int i;
95 	irq_hw_number_t hwirq;
96 	struct irq_fwspec *fwspec = arg;
97 	struct irq_fwspec gic_fwspec = *fwspec;
98 
99 	if (fwspec->param_count != 3)
100 		return -EINVAL;
101 
102 	/* sysirq doesn't support PPI */
103 	if (fwspec->param[0])
104 		return -EINVAL;
105 
106 	hwirq = fwspec->param[1];
107 	for (i = 0; i < nr_irqs; i++)
108 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
109 					      &mtk_sysirq_chip,
110 					      domain->host_data);
111 
112 	gic_fwspec.fwnode = domain->parent->fwnode;
113 	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &gic_fwspec);
114 }
115 
116 static const struct irq_domain_ops sysirq_domain_ops = {
117 	.translate	= mtk_sysirq_domain_translate,
118 	.alloc		= mtk_sysirq_domain_alloc,
119 	.free		= irq_domain_free_irqs_common,
120 };
121 
122 static int __init mtk_sysirq_of_init(struct device_node *node,
123 				     struct device_node *parent)
124 {
125 	struct irq_domain *domain, *domain_parent;
126 	struct mtk_sysirq_chip_data *chip_data;
127 	int ret, size, intpol_num = 0, nr_intpol_bases = 0, i = 0;
128 
129 	domain_parent = irq_find_host(parent);
130 	if (!domain_parent) {
131 		pr_err("mtk_sysirq: interrupt-parent not found\n");
132 		return -EINVAL;
133 	}
134 
135 	chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
136 	if (!chip_data)
137 		return -ENOMEM;
138 
139 	while (of_get_address(node, i++, NULL, NULL))
140 		nr_intpol_bases++;
141 
142 	if (nr_intpol_bases == 0) {
143 		pr_err("mtk_sysirq: base address not specified\n");
144 		ret = -EINVAL;
145 		goto out_free_chip;
146 	}
147 
148 	chip_data->intpol_words = kcalloc(nr_intpol_bases,
149 					  sizeof(*chip_data->intpol_words),
150 					  GFP_KERNEL);
151 	if (!chip_data->intpol_words) {
152 		ret = -ENOMEM;
153 		goto out_free_chip;
154 	}
155 
156 	chip_data->intpol_bases = kcalloc(nr_intpol_bases,
157 					  sizeof(*chip_data->intpol_bases),
158 					  GFP_KERNEL);
159 	if (!chip_data->intpol_bases) {
160 		ret = -ENOMEM;
161 		goto out_free_intpol_words;
162 	}
163 
164 	for (i = 0; i < nr_intpol_bases; i++) {
165 		struct resource res;
166 
167 		ret = of_address_to_resource(node, i, &res);
168 		size = resource_size(&res);
169 		intpol_num += size * 8;
170 		chip_data->intpol_words[i] = size / 4;
171 		chip_data->intpol_bases[i] = of_iomap(node, i);
172 		if (ret || !chip_data->intpol_bases[i]) {
173 			pr_err("%pOF: couldn't map region %d\n", node, i);
174 			ret = -ENODEV;
175 			goto out_free_intpol;
176 		}
177 	}
178 
179 	chip_data->intpol_idx = kcalloc(intpol_num,
180 					sizeof(*chip_data->intpol_idx),
181 					GFP_KERNEL);
182 	if (!chip_data->intpol_idx) {
183 		ret = -ENOMEM;
184 		goto out_free_intpol;
185 	}
186 
187 	chip_data->which_word = kcalloc(intpol_num,
188 					sizeof(*chip_data->which_word),
189 					GFP_KERNEL);
190 	if (!chip_data->which_word) {
191 		ret = -ENOMEM;
192 		goto out_free_intpol_idx;
193 	}
194 
195 	/*
196 	 * assign an index of the intpol_bases for each irq
197 	 * to set it fast later
198 	 */
199 	for (i = 0; i < intpol_num ; i++) {
200 		u32 word = i / 32, j;
201 
202 		for (j = 0; word >= chip_data->intpol_words[j] ; j++)
203 			word -= chip_data->intpol_words[j];
204 
205 		chip_data->intpol_idx[i] = j;
206 		chip_data->which_word[i] = word;
207 	}
208 
209 	domain = irq_domain_add_hierarchy(domain_parent, 0, intpol_num, node,
210 					  &sysirq_domain_ops, chip_data);
211 	if (!domain) {
212 		ret = -ENOMEM;
213 		goto out_free_which_word;
214 	}
215 	raw_spin_lock_init(&chip_data->lock);
216 
217 	return 0;
218 
219 out_free_which_word:
220 	kfree(chip_data->which_word);
221 out_free_intpol_idx:
222 	kfree(chip_data->intpol_idx);
223 out_free_intpol:
224 	for (i = 0; i < nr_intpol_bases; i++)
225 		if (chip_data->intpol_bases[i])
226 			iounmap(chip_data->intpol_bases[i]);
227 	kfree(chip_data->intpol_bases);
228 out_free_intpol_words:
229 	kfree(chip_data->intpol_words);
230 out_free_chip:
231 	kfree(chip_data);
232 	return ret;
233 }
234 IRQCHIP_DECLARE(mtk_sysirq, "mediatek,mt6577-sysirq", mtk_sysirq_of_init);
235