1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  CLPS711X IRQ driver
4 *
5 *  Copyright (C) 2013 Alexander Shiyan <shc_work@mail.ru>
6 */
7
8#include <linux/io.h>
9#include <linux/irq.h>
10#include <linux/irqchip.h>
11#include <linux/irqdomain.h>
12#include <linux/of_address.h>
13#include <linux/of_irq.h>
14#include <linux/slab.h>
15
16#include <asm/exception.h>
17#include <asm/mach/irq.h>
18
19#define CLPS711X_INTSR1	(0x0240)
20#define CLPS711X_INTMR1	(0x0280)
21#define CLPS711X_BLEOI	(0x0600)
22#define CLPS711X_MCEOI	(0x0640)
23#define CLPS711X_TEOI	(0x0680)
24#define CLPS711X_TC1EOI	(0x06c0)
25#define CLPS711X_TC2EOI	(0x0700)
26#define CLPS711X_RTCEOI	(0x0740)
27#define CLPS711X_UMSEOI	(0x0780)
28#define CLPS711X_COEOI	(0x07c0)
29#define CLPS711X_INTSR2	(0x1240)
30#define CLPS711X_INTMR2	(0x1280)
31#define CLPS711X_SRXEOF	(0x1600)
32#define CLPS711X_KBDEOI	(0x1700)
33#define CLPS711X_INTSR3	(0x2240)
34#define CLPS711X_INTMR3	(0x2280)
35
36static const struct {
37#define CLPS711X_FLAG_EN	(1 << 0)
38#define CLPS711X_FLAG_FIQ	(1 << 1)
39	unsigned int	flags;
40	phys_addr_t	eoi;
41} clps711x_irqs[] = {
42	[1]	= { CLPS711X_FLAG_FIQ, CLPS711X_BLEOI, },
43	[3]	= { CLPS711X_FLAG_FIQ, CLPS711X_MCEOI, },
44	[4]	= { CLPS711X_FLAG_EN, CLPS711X_COEOI, },
45	[5]	= { CLPS711X_FLAG_EN, },
46	[6]	= { CLPS711X_FLAG_EN, },
47	[7]	= { CLPS711X_FLAG_EN, },
48	[8]	= { CLPS711X_FLAG_EN, CLPS711X_TC1EOI, },
49	[9]	= { CLPS711X_FLAG_EN, CLPS711X_TC2EOI, },
50	[10]	= { CLPS711X_FLAG_EN, CLPS711X_RTCEOI, },
51	[11]	= { CLPS711X_FLAG_EN, CLPS711X_TEOI, },
52	[12]	= { CLPS711X_FLAG_EN, },
53	[13]	= { CLPS711X_FLAG_EN, },
54	[14]	= { CLPS711X_FLAG_EN, CLPS711X_UMSEOI, },
55	[15]	= { CLPS711X_FLAG_EN, CLPS711X_SRXEOF, },
56	[16]	= { CLPS711X_FLAG_EN, CLPS711X_KBDEOI, },
57	[17]	= { CLPS711X_FLAG_EN, },
58	[18]	= { CLPS711X_FLAG_EN, },
59	[28]	= { CLPS711X_FLAG_EN, },
60	[29]	= { CLPS711X_FLAG_EN, },
61	[32]	= { CLPS711X_FLAG_FIQ, },
62};
63
64static struct {
65	void __iomem		*base;
66	void __iomem		*intmr[3];
67	void __iomem		*intsr[3];
68	struct irq_domain	*domain;
69	struct irq_domain_ops	ops;
70} *clps711x_intc;
71
72static asmlinkage void __exception_irq_entry clps711x_irqh(struct pt_regs *regs)
73{
74	u32 irqstat;
75
76	do {
77		irqstat = readw_relaxed(clps711x_intc->intmr[0]) &
78			  readw_relaxed(clps711x_intc->intsr[0]);
79		if (irqstat)
80			generic_handle_domain_irq(clps711x_intc->domain,
81						  fls(irqstat) - 1);
82
83		irqstat = readw_relaxed(clps711x_intc->intmr[1]) &
84			  readw_relaxed(clps711x_intc->intsr[1]);
85		if (irqstat)
86			generic_handle_domain_irq(clps711x_intc->domain,
87						  fls(irqstat) - 1 + 16);
88	} while (irqstat);
89}
90
91static void clps711x_intc_eoi(struct irq_data *d)
92{
93	irq_hw_number_t hwirq = irqd_to_hwirq(d);
94
95	writel_relaxed(0, clps711x_intc->base + clps711x_irqs[hwirq].eoi);
96}
97
98static void clps711x_intc_mask(struct irq_data *d)
99{
100	irq_hw_number_t hwirq = irqd_to_hwirq(d);
101	void __iomem *intmr = clps711x_intc->intmr[hwirq / 16];
102	u32 tmp;
103
104	tmp = readl_relaxed(intmr);
105	tmp &= ~(1 << (hwirq % 16));
106	writel_relaxed(tmp, intmr);
107}
108
109static void clps711x_intc_unmask(struct irq_data *d)
110{
111	irq_hw_number_t hwirq = irqd_to_hwirq(d);
112	void __iomem *intmr = clps711x_intc->intmr[hwirq / 16];
113	u32 tmp;
114
115	tmp = readl_relaxed(intmr);
116	tmp |= 1 << (hwirq % 16);
117	writel_relaxed(tmp, intmr);
118}
119
120static struct irq_chip clps711x_intc_chip = {
121	.name		= "clps711x-intc",
122	.irq_eoi	= clps711x_intc_eoi,
123	.irq_mask	= clps711x_intc_mask,
124	.irq_unmask	= clps711x_intc_unmask,
125};
126
127static int __init clps711x_intc_irq_map(struct irq_domain *h, unsigned int virq,
128					irq_hw_number_t hw)
129{
130	irq_flow_handler_t handler = handle_level_irq;
131	unsigned int flags = 0;
132
133	if (!clps711x_irqs[hw].flags)
134		return 0;
135
136	if (clps711x_irqs[hw].flags & CLPS711X_FLAG_FIQ) {
137		handler = handle_bad_irq;
138		flags |= IRQ_NOAUTOEN;
139	} else if (clps711x_irqs[hw].eoi) {
140		handler = handle_fasteoi_irq;
141	}
142
143	/* Clear down pending interrupt */
144	if (clps711x_irqs[hw].eoi)
145		writel_relaxed(0, clps711x_intc->base + clps711x_irqs[hw].eoi);
146
147	irq_set_chip_and_handler(virq, &clps711x_intc_chip, handler);
148	irq_modify_status(virq, IRQ_NOPROBE, flags);
149
150	return 0;
151}
152
153static int __init _clps711x_intc_init(struct device_node *np,
154				      phys_addr_t base, resource_size_t size)
155{
156	int err;
157
158	clps711x_intc = kzalloc(sizeof(*clps711x_intc), GFP_KERNEL);
159	if (!clps711x_intc)
160		return -ENOMEM;
161
162	clps711x_intc->base = ioremap(base, size);
163	if (!clps711x_intc->base) {
164		err = -ENOMEM;
165		goto out_kfree;
166	}
167
168	clps711x_intc->intsr[0] = clps711x_intc->base + CLPS711X_INTSR1;
169	clps711x_intc->intmr[0] = clps711x_intc->base + CLPS711X_INTMR1;
170	clps711x_intc->intsr[1] = clps711x_intc->base + CLPS711X_INTSR2;
171	clps711x_intc->intmr[1] = clps711x_intc->base + CLPS711X_INTMR2;
172	clps711x_intc->intsr[2] = clps711x_intc->base + CLPS711X_INTSR3;
173	clps711x_intc->intmr[2] = clps711x_intc->base + CLPS711X_INTMR3;
174
175	/* Mask all interrupts */
176	writel_relaxed(0, clps711x_intc->intmr[0]);
177	writel_relaxed(0, clps711x_intc->intmr[1]);
178	writel_relaxed(0, clps711x_intc->intmr[2]);
179
180	err = irq_alloc_descs(-1, 0, ARRAY_SIZE(clps711x_irqs), numa_node_id());
181	if (err < 0)
182		goto out_iounmap;
183
184	clps711x_intc->ops.map = clps711x_intc_irq_map;
185	clps711x_intc->ops.xlate = irq_domain_xlate_onecell;
186	clps711x_intc->domain =
187		irq_domain_add_legacy(np, ARRAY_SIZE(clps711x_irqs),
188				      0, 0, &clps711x_intc->ops, NULL);
189	if (!clps711x_intc->domain) {
190		err = -ENOMEM;
191		goto out_irqfree;
192	}
193
194	irq_set_default_host(clps711x_intc->domain);
195	set_handle_irq(clps711x_irqh);
196
197#ifdef CONFIG_FIQ
198	init_FIQ(0);
199#endif
200
201	return 0;
202
203out_irqfree:
204	irq_free_descs(0, ARRAY_SIZE(clps711x_irqs));
205
206out_iounmap:
207	iounmap(clps711x_intc->base);
208
209out_kfree:
210	kfree(clps711x_intc);
211
212	return err;
213}
214
215static int __init clps711x_intc_init_dt(struct device_node *np,
216					struct device_node *parent)
217{
218	struct resource res;
219	int err;
220
221	err = of_address_to_resource(np, 0, &res);
222	if (err)
223		return err;
224
225	return _clps711x_intc_init(np, res.start, resource_size(&res));
226}
227IRQCHIP_DECLARE(clps711x, "cirrus,ep7209-intc", clps711x_intc_init_dt);
228