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
17struct 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
26static 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
60static 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
71static 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
92static 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
117static 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
123static 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
220out_free_which_word:
221	kfree(chip_data->which_word);
222out_free_intpol_idx:
223	kfree(chip_data->intpol_idx);
224out_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);
229out_free_intpol_words:
230	kfree(chip_data->intpol_words);
231out_free_chip:
232	kfree(chip_data);
233	return ret;
234}
235IRQCHIP_DECLARE(mtk_sysirq, "mediatek,mt6577-sysirq", mtk_sysirq_of_init);
236