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 	.flags			= IRQCHIP_SKIP_SET_WAKE,
69 };
70 
71 static int mtk_sysirq_domain_translate(struct irq_domain *d,
72 				       struct irq_fwspec *fwspec,
73 				       unsigned long *hwirq,
74 				       unsigned int *type)
75 {
76 	if (is_of_node(fwspec->fwnode)) {
77 		if (fwspec->param_count != 3)
78 			return -EINVAL;
79 
80 		/* No PPI should point to this domain */
81 		if (fwspec->param[0] != 0)
82 			return -EINVAL;
83 
84 		*hwirq = fwspec->param[1];
85 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
86 		return 0;
87 	}
88 
89 	return -EINVAL;
90 }
91 
92 static int mtk_sysirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
93 				   unsigned int nr_irqs, void *arg)
94 {
95 	int i;
96 	irq_hw_number_t hwirq;
97 	struct irq_fwspec *fwspec = arg;
98 	struct irq_fwspec gic_fwspec = *fwspec;
99 
100 	if (fwspec->param_count != 3)
101 		return -EINVAL;
102 
103 	/* sysirq doesn't support PPI */
104 	if (fwspec->param[0])
105 		return -EINVAL;
106 
107 	hwirq = fwspec->param[1];
108 	for (i = 0; i < nr_irqs; i++)
109 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
110 					      &mtk_sysirq_chip,
111 					      domain->host_data);
112 
113 	gic_fwspec.fwnode = domain->parent->fwnode;
114 	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &gic_fwspec);
115 }
116 
117 static const struct irq_domain_ops sysirq_domain_ops = {
118 	.translate	= mtk_sysirq_domain_translate,
119 	.alloc		= mtk_sysirq_domain_alloc,
120 	.free		= irq_domain_free_irqs_common,
121 };
122 
123 static int __init mtk_sysirq_of_init(struct device_node *node,
124 				     struct device_node *parent)
125 {
126 	struct irq_domain *domain, *domain_parent;
127 	struct mtk_sysirq_chip_data *chip_data;
128 	int ret, size, intpol_num = 0, nr_intpol_bases = 0, i = 0;
129 
130 	domain_parent = irq_find_host(parent);
131 	if (!domain_parent) {
132 		pr_err("mtk_sysirq: interrupt-parent not found\n");
133 		return -EINVAL;
134 	}
135 
136 	chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
137 	if (!chip_data)
138 		return -ENOMEM;
139 
140 	while (of_get_address(node, i++, NULL, NULL))
141 		nr_intpol_bases++;
142 
143 	if (nr_intpol_bases == 0) {
144 		pr_err("mtk_sysirq: base address not specified\n");
145 		ret = -EINVAL;
146 		goto out_free_chip;
147 	}
148 
149 	chip_data->intpol_words = kcalloc(nr_intpol_bases,
150 					  sizeof(*chip_data->intpol_words),
151 					  GFP_KERNEL);
152 	if (!chip_data->intpol_words) {
153 		ret = -ENOMEM;
154 		goto out_free_chip;
155 	}
156 
157 	chip_data->intpol_bases = kcalloc(nr_intpol_bases,
158 					  sizeof(*chip_data->intpol_bases),
159 					  GFP_KERNEL);
160 	if (!chip_data->intpol_bases) {
161 		ret = -ENOMEM;
162 		goto out_free_intpol_words;
163 	}
164 
165 	for (i = 0; i < nr_intpol_bases; i++) {
166 		struct resource res;
167 
168 		ret = of_address_to_resource(node, i, &res);
169 		size = resource_size(&res);
170 		intpol_num += size * 8;
171 		chip_data->intpol_words[i] = size / 4;
172 		chip_data->intpol_bases[i] = of_iomap(node, i);
173 		if (ret || !chip_data->intpol_bases[i]) {
174 			pr_err("%pOF: couldn't map region %d\n", node, i);
175 			ret = -ENODEV;
176 			goto out_free_intpol;
177 		}
178 	}
179 
180 	chip_data->intpol_idx = kcalloc(intpol_num,
181 					sizeof(*chip_data->intpol_idx),
182 					GFP_KERNEL);
183 	if (!chip_data->intpol_idx) {
184 		ret = -ENOMEM;
185 		goto out_free_intpol;
186 	}
187 
188 	chip_data->which_word = kcalloc(intpol_num,
189 					sizeof(*chip_data->which_word),
190 					GFP_KERNEL);
191 	if (!chip_data->which_word) {
192 		ret = -ENOMEM;
193 		goto out_free_intpol_idx;
194 	}
195 
196 	/*
197 	 * assign an index of the intpol_bases for each irq
198 	 * to set it fast later
199 	 */
200 	for (i = 0; i < intpol_num ; i++) {
201 		u32 word = i / 32, j;
202 
203 		for (j = 0; word >= chip_data->intpol_words[j] ; j++)
204 			word -= chip_data->intpol_words[j];
205 
206 		chip_data->intpol_idx[i] = j;
207 		chip_data->which_word[i] = word;
208 	}
209 
210 	domain = irq_domain_add_hierarchy(domain_parent, 0, intpol_num, node,
211 					  &sysirq_domain_ops, chip_data);
212 	if (!domain) {
213 		ret = -ENOMEM;
214 		goto out_free_which_word;
215 	}
216 	raw_spin_lock_init(&chip_data->lock);
217 
218 	return 0;
219 
220 out_free_which_word:
221 	kfree(chip_data->which_word);
222 out_free_intpol_idx:
223 	kfree(chip_data->intpol_idx);
224 out_free_intpol:
225 	for (i = 0; i < nr_intpol_bases; i++)
226 		if (chip_data->intpol_bases[i])
227 			iounmap(chip_data->intpol_bases[i]);
228 	kfree(chip_data->intpol_bases);
229 out_free_intpol_words:
230 	kfree(chip_data->intpol_words);
231 out_free_chip:
232 	kfree(chip_data);
233 	return ret;
234 }
235 IRQCHIP_DECLARE(mtk_sysirq, "mediatek,mt6577-sysirq", mtk_sysirq_of_init);
236