1// SPDX-License-Identifier: (GPL-2.0 OR MIT)
2/*
3 * Microsemi Ocelot IRQ controller driver
4 *
5 * Copyright (c) 2017 Microsemi Corporation
6 */
7#include <linux/bitops.h>
8#include <linux/irq.h>
9#include <linux/of_address.h>
10#include <linux/of_irq.h>
11#include <linux/irqchip.h>
12#include <linux/irqchip/chained_irq.h>
13#include <linux/interrupt.h>
14
15#define ICPU_CFG_INTR_DST_INTR_IDENT(_p, x) ((_p)->reg_off_ident + 0x4 * (x))
16#define ICPU_CFG_INTR_INTR_TRIGGER(_p, x)   ((_p)->reg_off_trigger + 0x4 * (x))
17
18#define FLAGS_HAS_TRIGGER	BIT(0)
19#define FLAGS_NEED_INIT_ENABLE	BIT(1)
20
21struct chip_props {
22	u8 flags;
23	u8 reg_off_sticky;
24	u8 reg_off_ena;
25	u8 reg_off_ena_clr;
26	u8 reg_off_ena_set;
27	u8 reg_off_ident;
28	u8 reg_off_trigger;
29	u8 reg_off_ena_irq0;
30	u8 n_irq;
31};
32
33static struct chip_props ocelot_props = {
34	.flags			= FLAGS_HAS_TRIGGER,
35	.reg_off_sticky		= 0x10,
36	.reg_off_ena		= 0x18,
37	.reg_off_ena_clr	= 0x1c,
38	.reg_off_ena_set	= 0x20,
39	.reg_off_ident		= 0x38,
40	.reg_off_trigger	= 0x5c,
41	.n_irq			= 24,
42};
43
44static struct chip_props serval_props = {
45	.flags			= FLAGS_HAS_TRIGGER,
46	.reg_off_sticky		= 0xc,
47	.reg_off_ena		= 0x14,
48	.reg_off_ena_clr	= 0x18,
49	.reg_off_ena_set	= 0x1c,
50	.reg_off_ident		= 0x20,
51	.reg_off_trigger	= 0x4,
52	.n_irq			= 24,
53};
54
55static struct chip_props luton_props = {
56	.flags			= FLAGS_NEED_INIT_ENABLE,
57	.reg_off_sticky		= 0,
58	.reg_off_ena		= 0x4,
59	.reg_off_ena_clr	= 0x8,
60	.reg_off_ena_set	= 0xc,
61	.reg_off_ident		= 0x18,
62	.reg_off_ena_irq0	= 0x14,
63	.n_irq			= 28,
64};
65
66static struct chip_props jaguar2_props = {
67	.flags			= FLAGS_HAS_TRIGGER,
68	.reg_off_sticky		= 0x10,
69	.reg_off_ena		= 0x18,
70	.reg_off_ena_clr	= 0x1c,
71	.reg_off_ena_set	= 0x20,
72	.reg_off_ident		= 0x38,
73	.reg_off_trigger	= 0x5c,
74	.n_irq			= 29,
75};
76
77static void ocelot_irq_unmask(struct irq_data *data)
78{
79	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
80	struct irq_domain *d = data->domain;
81	struct chip_props *p = d->host_data;
82	struct irq_chip_type *ct = irq_data_get_chip_type(data);
83	unsigned int mask = data->mask;
84	u32 val;
85
86	irq_gc_lock(gc);
87	val = irq_reg_readl(gc, ICPU_CFG_INTR_INTR_TRIGGER(p, 0)) |
88		irq_reg_readl(gc, ICPU_CFG_INTR_INTR_TRIGGER(p, 1));
89	if (!(val & mask))
90		irq_reg_writel(gc, mask, p->reg_off_sticky);
91
92	*ct->mask_cache &= ~mask;
93	irq_reg_writel(gc, mask, p->reg_off_ena_set);
94	irq_gc_unlock(gc);
95}
96
97static void ocelot_irq_handler(struct irq_desc *desc)
98{
99	struct irq_chip *chip = irq_desc_get_chip(desc);
100	struct irq_domain *d = irq_desc_get_handler_data(desc);
101	struct chip_props *p = d->host_data;
102	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, 0);
103	u32 reg = irq_reg_readl(gc, ICPU_CFG_INTR_DST_INTR_IDENT(p, 0));
104
105	chained_irq_enter(chip, desc);
106
107	while (reg) {
108		u32 hwirq = __fls(reg);
109
110		generic_handle_domain_irq(d, hwirq);
111		reg &= ~(BIT(hwirq));
112	}
113
114	chained_irq_exit(chip, desc);
115}
116
117static int __init vcoreiii_irq_init(struct device_node *node,
118				    struct device_node *parent,
119				    struct chip_props *p)
120{
121	struct irq_domain *domain;
122	struct irq_chip_generic *gc;
123	int parent_irq, ret;
124
125	parent_irq = irq_of_parse_and_map(node, 0);
126	if (!parent_irq)
127		return -EINVAL;
128
129	domain = irq_domain_add_linear(node, p->n_irq,
130				       &irq_generic_chip_ops, NULL);
131	if (!domain) {
132		pr_err("%pOFn: unable to add irq domain\n", node);
133		return -ENOMEM;
134	}
135
136	ret = irq_alloc_domain_generic_chips(domain, p->n_irq, 1,
137					     "icpu", handle_level_irq,
138					     0, 0, 0);
139	if (ret) {
140		pr_err("%pOFn: unable to alloc irq domain gc\n", node);
141		goto err_domain_remove;
142	}
143
144	gc = irq_get_domain_generic_chip(domain, 0);
145	gc->reg_base = of_iomap(node, 0);
146	if (!gc->reg_base) {
147		pr_err("%pOFn: unable to map resource\n", node);
148		ret = -ENOMEM;
149		goto err_gc_free;
150	}
151
152	gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
153	gc->chip_types[0].regs.ack = p->reg_off_sticky;
154	if (p->flags & FLAGS_HAS_TRIGGER) {
155		gc->chip_types[0].regs.mask = p->reg_off_ena_clr;
156		gc->chip_types[0].chip.irq_unmask = ocelot_irq_unmask;
157		gc->chip_types[0].chip.irq_mask = irq_gc_mask_set_bit;
158	} else {
159		gc->chip_types[0].regs.enable = p->reg_off_ena_set;
160		gc->chip_types[0].regs.disable = p->reg_off_ena_clr;
161		gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg;
162		gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg;
163	}
164
165	/* Mask and ack all interrupts */
166	irq_reg_writel(gc, 0, p->reg_off_ena);
167	irq_reg_writel(gc, 0xffffffff, p->reg_off_sticky);
168
169	/* Overall init */
170	if (p->flags & FLAGS_NEED_INIT_ENABLE)
171		irq_reg_writel(gc, BIT(0), p->reg_off_ena_irq0);
172
173	domain->host_data = p;
174	irq_set_chained_handler_and_data(parent_irq, ocelot_irq_handler,
175					 domain);
176
177	return 0;
178
179err_gc_free:
180	irq_free_generic_chip(gc);
181
182err_domain_remove:
183	irq_domain_remove(domain);
184
185	return ret;
186}
187
188static int __init ocelot_irq_init(struct device_node *node,
189				  struct device_node *parent)
190{
191	return vcoreiii_irq_init(node, parent, &ocelot_props);
192}
193
194IRQCHIP_DECLARE(ocelot_icpu, "mscc,ocelot-icpu-intr", ocelot_irq_init);
195
196static int __init serval_irq_init(struct device_node *node,
197				  struct device_node *parent)
198{
199	return vcoreiii_irq_init(node, parent, &serval_props);
200}
201
202IRQCHIP_DECLARE(serval_icpu, "mscc,serval-icpu-intr", serval_irq_init);
203
204static int __init luton_irq_init(struct device_node *node,
205				 struct device_node *parent)
206{
207	return vcoreiii_irq_init(node, parent, &luton_props);
208}
209
210IRQCHIP_DECLARE(luton_icpu, "mscc,luton-icpu-intr", luton_irq_init);
211
212static int __init jaguar2_irq_init(struct device_node *node,
213				   struct device_node *parent)
214{
215	return vcoreiii_irq_init(node, parent, &jaguar2_props);
216}
217
218IRQCHIP_DECLARE(jaguar2_icpu, "mscc,jaguar2-icpu-intr", jaguar2_irq_init);
219