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 
36 static 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 
64 static 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 
72 static 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 
91 static 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 
98 static 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 
109 static 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 
120 static 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 
127 static 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 
153 static 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 
203 out_irqfree:
204 	irq_free_descs(0, ARRAY_SIZE(clps711x_irqs));
205 
206 out_iounmap:
207 	iounmap(clps711x_intc->base);
208 
209 out_kfree:
210 	kfree(clps711x_intc);
211 
212 	return err;
213 }
214 
215 static 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 }
227 IRQCHIP_DECLARE(clps711x, "cirrus,ep7209-intc", clps711x_intc_init_dt);
228