1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Actions Semi Owl SoCs SIRQ interrupt controller driver
4  *
5  * Copyright (C) 2014 Actions Semi Inc.
6  * David Liu <liuwei@actions-semi.com>
7  *
8  * Author: Parthiban Nallathambi <pn@denx.de>
9  * Author: Saravanan Sekar <sravanhome@gmail.com>
10  * Author: Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
11  */
12 
13 #include <linux/bitfield.h>
14 #include <linux/interrupt.h>
15 #include <linux/irqchip.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 
19 #include <dt-bindings/interrupt-controller/arm-gic.h>
20 
21 #define NUM_SIRQ			3
22 
23 #define INTC_EXTCTL_PENDING		BIT(0)
24 #define INTC_EXTCTL_CLK_SEL		BIT(4)
25 #define INTC_EXTCTL_EN			BIT(5)
26 #define INTC_EXTCTL_TYPE_MASK		GENMASK(7, 6)
27 #define INTC_EXTCTL_TYPE_HIGH		0
28 #define INTC_EXTCTL_TYPE_LOW		BIT(6)
29 #define INTC_EXTCTL_TYPE_RISING		BIT(7)
30 #define INTC_EXTCTL_TYPE_FALLING	(BIT(6) | BIT(7))
31 
32 /* S500 & S700 SIRQ control register masks */
33 #define INTC_EXTCTL_SIRQ0_MASK		GENMASK(23, 16)
34 #define INTC_EXTCTL_SIRQ1_MASK		GENMASK(15, 8)
35 #define INTC_EXTCTL_SIRQ2_MASK		GENMASK(7, 0)
36 
37 /* S900 SIRQ control register offsets, relative to controller base address */
38 #define INTC_EXTCTL0			0x0000
39 #define INTC_EXTCTL1			0x0328
40 #define INTC_EXTCTL2			0x032c
41 
42 struct owl_sirq_params {
43 	/* INTC_EXTCTL reg shared for all three SIRQ lines */
44 	bool reg_shared;
45 	/* INTC_EXTCTL reg offsets relative to controller base address */
46 	u16 reg_offset[NUM_SIRQ];
47 };
48 
49 struct owl_sirq_chip_data {
50 	const struct owl_sirq_params	*params;
51 	void __iomem			*base;
52 	raw_spinlock_t			lock;
53 	u32				ext_irqs[NUM_SIRQ];
54 };
55 
56 /* S500 & S700 SoCs */
57 static const struct owl_sirq_params owl_sirq_s500_params = {
58 	.reg_shared = true,
59 	.reg_offset = { 0, 0, 0 },
60 };
61 
62 /* S900 SoC */
63 static const struct owl_sirq_params owl_sirq_s900_params = {
64 	.reg_shared = false,
65 	.reg_offset = { INTC_EXTCTL0, INTC_EXTCTL1, INTC_EXTCTL2 },
66 };
67 
68 static u32 owl_field_get(u32 val, u32 index)
69 {
70 	switch (index) {
71 	case 0:
72 		return FIELD_GET(INTC_EXTCTL_SIRQ0_MASK, val);
73 	case 1:
74 		return FIELD_GET(INTC_EXTCTL_SIRQ1_MASK, val);
75 	case 2:
76 	default:
77 		return FIELD_GET(INTC_EXTCTL_SIRQ2_MASK, val);
78 	}
79 }
80 
81 static u32 owl_field_prep(u32 val, u32 index)
82 {
83 	switch (index) {
84 	case 0:
85 		return FIELD_PREP(INTC_EXTCTL_SIRQ0_MASK, val);
86 	case 1:
87 		return FIELD_PREP(INTC_EXTCTL_SIRQ1_MASK, val);
88 	case 2:
89 	default:
90 		return FIELD_PREP(INTC_EXTCTL_SIRQ2_MASK, val);
91 	}
92 }
93 
94 static u32 owl_sirq_read_extctl(struct owl_sirq_chip_data *data, u32 index)
95 {
96 	u32 val;
97 
98 	val = readl_relaxed(data->base + data->params->reg_offset[index]);
99 	if (data->params->reg_shared)
100 		val = owl_field_get(val, index);
101 
102 	return val;
103 }
104 
105 static void owl_sirq_write_extctl(struct owl_sirq_chip_data *data,
106 				  u32 extctl, u32 index)
107 {
108 	u32 val;
109 
110 	if (data->params->reg_shared) {
111 		val = readl_relaxed(data->base + data->params->reg_offset[index]);
112 		val &= ~owl_field_prep(0xff, index);
113 		extctl = owl_field_prep(extctl, index) | val;
114 	}
115 
116 	writel_relaxed(extctl, data->base + data->params->reg_offset[index]);
117 }
118 
119 static void owl_sirq_clear_set_extctl(struct owl_sirq_chip_data *d,
120 				      u32 clear, u32 set, u32 index)
121 {
122 	unsigned long flags;
123 	u32 val;
124 
125 	raw_spin_lock_irqsave(&d->lock, flags);
126 	val = owl_sirq_read_extctl(d, index);
127 	val &= ~clear;
128 	val |= set;
129 	owl_sirq_write_extctl(d, val, index);
130 	raw_spin_unlock_irqrestore(&d->lock, flags);
131 }
132 
133 static void owl_sirq_eoi(struct irq_data *data)
134 {
135 	struct owl_sirq_chip_data *chip_data = irq_data_get_irq_chip_data(data);
136 
137 	/*
138 	 * Software must clear external interrupt pending, when interrupt type
139 	 * is edge triggered, so we need per SIRQ based clearing.
140 	 */
141 	if (!irqd_is_level_type(data))
142 		owl_sirq_clear_set_extctl(chip_data, 0, INTC_EXTCTL_PENDING,
143 					  data->hwirq);
144 
145 	irq_chip_eoi_parent(data);
146 }
147 
148 static void owl_sirq_mask(struct irq_data *data)
149 {
150 	struct owl_sirq_chip_data *chip_data = irq_data_get_irq_chip_data(data);
151 
152 	owl_sirq_clear_set_extctl(chip_data, INTC_EXTCTL_EN, 0, data->hwirq);
153 	irq_chip_mask_parent(data);
154 }
155 
156 static void owl_sirq_unmask(struct irq_data *data)
157 {
158 	struct owl_sirq_chip_data *chip_data = irq_data_get_irq_chip_data(data);
159 
160 	owl_sirq_clear_set_extctl(chip_data, 0, INTC_EXTCTL_EN, data->hwirq);
161 	irq_chip_unmask_parent(data);
162 }
163 
164 /*
165  * GIC does not handle falling edge or active low, hence SIRQ shall be
166  * programmed to convert falling edge to rising edge signal and active
167  * low to active high signal.
168  */
169 static int owl_sirq_set_type(struct irq_data *data, unsigned int type)
170 {
171 	struct owl_sirq_chip_data *chip_data = irq_data_get_irq_chip_data(data);
172 	u32 sirq_type;
173 
174 	switch (type) {
175 	case IRQ_TYPE_LEVEL_LOW:
176 		sirq_type = INTC_EXTCTL_TYPE_LOW;
177 		type = IRQ_TYPE_LEVEL_HIGH;
178 		break;
179 	case IRQ_TYPE_LEVEL_HIGH:
180 		sirq_type = INTC_EXTCTL_TYPE_HIGH;
181 		break;
182 	case IRQ_TYPE_EDGE_FALLING:
183 		sirq_type = INTC_EXTCTL_TYPE_FALLING;
184 		type = IRQ_TYPE_EDGE_RISING;
185 		break;
186 	case IRQ_TYPE_EDGE_RISING:
187 		sirq_type = INTC_EXTCTL_TYPE_RISING;
188 		break;
189 	default:
190 		return -EINVAL;
191 	}
192 
193 	owl_sirq_clear_set_extctl(chip_data, INTC_EXTCTL_TYPE_MASK, sirq_type,
194 				  data->hwirq);
195 
196 	return irq_chip_set_type_parent(data, type);
197 }
198 
199 static struct irq_chip owl_sirq_chip = {
200 	.name		= "owl-sirq",
201 	.irq_mask	= owl_sirq_mask,
202 	.irq_unmask	= owl_sirq_unmask,
203 	.irq_eoi	= owl_sirq_eoi,
204 	.irq_set_type	= owl_sirq_set_type,
205 	.irq_retrigger	= irq_chip_retrigger_hierarchy,
206 #ifdef CONFIG_SMP
207 	.irq_set_affinity = irq_chip_set_affinity_parent,
208 #endif
209 };
210 
211 static int owl_sirq_domain_translate(struct irq_domain *d,
212 				     struct irq_fwspec *fwspec,
213 				     unsigned long *hwirq,
214 				     unsigned int *type)
215 {
216 	if (!is_of_node(fwspec->fwnode))
217 		return -EINVAL;
218 
219 	if (fwspec->param_count != 2 || fwspec->param[0] >= NUM_SIRQ)
220 		return -EINVAL;
221 
222 	*hwirq = fwspec->param[0];
223 	*type = fwspec->param[1];
224 
225 	return 0;
226 }
227 
228 static int owl_sirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
229 				 unsigned int nr_irqs, void *data)
230 {
231 	struct owl_sirq_chip_data *chip_data = domain->host_data;
232 	struct irq_fwspec *fwspec = data;
233 	struct irq_fwspec parent_fwspec;
234 	irq_hw_number_t hwirq;
235 	unsigned int type;
236 	int ret;
237 
238 	if (WARN_ON(nr_irqs != 1))
239 		return -EINVAL;
240 
241 	ret = owl_sirq_domain_translate(domain, fwspec, &hwirq, &type);
242 	if (ret)
243 		return ret;
244 
245 	switch (type) {
246 	case IRQ_TYPE_EDGE_RISING:
247 	case IRQ_TYPE_LEVEL_HIGH:
248 		break;
249 	case IRQ_TYPE_EDGE_FALLING:
250 		type = IRQ_TYPE_EDGE_RISING;
251 		break;
252 	case IRQ_TYPE_LEVEL_LOW:
253 		type = IRQ_TYPE_LEVEL_HIGH;
254 		break;
255 	default:
256 		return -EINVAL;
257 	}
258 
259 	irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &owl_sirq_chip,
260 				      chip_data);
261 
262 	parent_fwspec.fwnode = domain->parent->fwnode;
263 	parent_fwspec.param_count = 3;
264 	parent_fwspec.param[0] = GIC_SPI;
265 	parent_fwspec.param[1] = chip_data->ext_irqs[hwirq];
266 	parent_fwspec.param[2] = type;
267 
268 	return irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
269 }
270 
271 static const struct irq_domain_ops owl_sirq_domain_ops = {
272 	.translate	= owl_sirq_domain_translate,
273 	.alloc		= owl_sirq_domain_alloc,
274 	.free		= irq_domain_free_irqs_common,
275 };
276 
277 static int __init owl_sirq_init(const struct owl_sirq_params *params,
278 				struct device_node *node,
279 				struct device_node *parent)
280 {
281 	struct irq_domain *domain, *parent_domain;
282 	struct owl_sirq_chip_data *chip_data;
283 	int ret, i;
284 
285 	parent_domain = irq_find_host(parent);
286 	if (!parent_domain) {
287 		pr_err("%pOF: failed to find sirq parent domain\n", node);
288 		return -ENXIO;
289 	}
290 
291 	chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
292 	if (!chip_data)
293 		return -ENOMEM;
294 
295 	raw_spin_lock_init(&chip_data->lock);
296 
297 	chip_data->params = params;
298 
299 	chip_data->base = of_iomap(node, 0);
300 	if (!chip_data->base) {
301 		pr_err("%pOF: failed to map sirq registers\n", node);
302 		ret = -ENXIO;
303 		goto out_free;
304 	}
305 
306 	for (i = 0; i < NUM_SIRQ; i++) {
307 		struct of_phandle_args irq;
308 
309 		ret = of_irq_parse_one(node, i, &irq);
310 		if (ret) {
311 			pr_err("%pOF: failed to parse interrupt %d\n", node, i);
312 			goto out_unmap;
313 		}
314 
315 		if (WARN_ON(irq.args_count != 3)) {
316 			ret = -EINVAL;
317 			goto out_unmap;
318 		}
319 
320 		chip_data->ext_irqs[i] = irq.args[1];
321 
322 		/* Set 24MHz external interrupt clock freq */
323 		owl_sirq_clear_set_extctl(chip_data, 0, INTC_EXTCTL_CLK_SEL, i);
324 	}
325 
326 	domain = irq_domain_add_hierarchy(parent_domain, 0, NUM_SIRQ, node,
327 					  &owl_sirq_domain_ops, chip_data);
328 	if (!domain) {
329 		pr_err("%pOF: failed to add domain\n", node);
330 		ret = -ENOMEM;
331 		goto out_unmap;
332 	}
333 
334 	return 0;
335 
336 out_unmap:
337 	iounmap(chip_data->base);
338 out_free:
339 	kfree(chip_data);
340 
341 	return ret;
342 }
343 
344 static int __init owl_sirq_s500_of_init(struct device_node *node,
345 					struct device_node *parent)
346 {
347 	return owl_sirq_init(&owl_sirq_s500_params, node, parent);
348 }
349 
350 IRQCHIP_DECLARE(owl_sirq_s500, "actions,s500-sirq", owl_sirq_s500_of_init);
351 IRQCHIP_DECLARE(owl_sirq_s700, "actions,s700-sirq", owl_sirq_s500_of_init);
352 
353 static int __init owl_sirq_s900_of_init(struct device_node *node,
354 					struct device_node *parent)
355 {
356 	return owl_sirq_init(&owl_sirq_s900_params, node, parent);
357 }
358 
359 IRQCHIP_DECLARE(owl_sirq_s900, "actions,s900-sirq", owl_sirq_s900_of_init);
360