xref: /openbmc/linux/drivers/irqchip/spear-shirq.c (revision 12eb4683)
1 /*
2  * SPEAr platform shared irq layer source file
3  *
4  * Copyright (C) 2009-2012 ST Microelectronics
5  * Viresh Kumar <viresh.linux@gmail.com>
6  *
7  * Copyright (C) 2012 ST Microelectronics
8  * Shiraz Hashim <shiraz.hashim@st.com>
9  *
10  * This file is licensed under the terms of the GNU General Public
11  * License version 2. This program is licensed "as is" without any
12  * warranty of any kind, whether express or implied.
13  */
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15 
16 #include <linux/err.h>
17 #include <linux/export.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/irq.h>
21 #include <linux/irqdomain.h>
22 #include <linux/irqchip/spear-shirq.h>
23 #include <linux/of.h>
24 #include <linux/of_address.h>
25 #include <linux/of_irq.h>
26 #include <linux/spinlock.h>
27 
28 #include "irqchip.h"
29 
30 static DEFINE_SPINLOCK(lock);
31 
32 /* spear300 shared irq registers offsets and masks */
33 #define SPEAR300_INT_ENB_MASK_REG	0x54
34 #define SPEAR300_INT_STS_MASK_REG	0x58
35 
36 static struct spear_shirq spear300_shirq_ras1 = {
37 	.irq_nr = 9,
38 	.irq_bit_off = 0,
39 	.regs = {
40 		.enb_reg = SPEAR300_INT_ENB_MASK_REG,
41 		.status_reg = SPEAR300_INT_STS_MASK_REG,
42 		.clear_reg = -1,
43 	},
44 };
45 
46 static struct spear_shirq *spear300_shirq_blocks[] = {
47 	&spear300_shirq_ras1,
48 };
49 
50 /* spear310 shared irq registers offsets and masks */
51 #define SPEAR310_INT_STS_MASK_REG	0x04
52 
53 static struct spear_shirq spear310_shirq_ras1 = {
54 	.irq_nr = 8,
55 	.irq_bit_off = 0,
56 	.regs = {
57 		.enb_reg = -1,
58 		.status_reg = SPEAR310_INT_STS_MASK_REG,
59 		.clear_reg = -1,
60 	},
61 };
62 
63 static struct spear_shirq spear310_shirq_ras2 = {
64 	.irq_nr = 5,
65 	.irq_bit_off = 8,
66 	.regs = {
67 		.enb_reg = -1,
68 		.status_reg = SPEAR310_INT_STS_MASK_REG,
69 		.clear_reg = -1,
70 	},
71 };
72 
73 static struct spear_shirq spear310_shirq_ras3 = {
74 	.irq_nr = 1,
75 	.irq_bit_off = 13,
76 	.regs = {
77 		.enb_reg = -1,
78 		.status_reg = SPEAR310_INT_STS_MASK_REG,
79 		.clear_reg = -1,
80 	},
81 };
82 
83 static struct spear_shirq spear310_shirq_intrcomm_ras = {
84 	.irq_nr = 3,
85 	.irq_bit_off = 14,
86 	.regs = {
87 		.enb_reg = -1,
88 		.status_reg = SPEAR310_INT_STS_MASK_REG,
89 		.clear_reg = -1,
90 	},
91 };
92 
93 static struct spear_shirq *spear310_shirq_blocks[] = {
94 	&spear310_shirq_ras1,
95 	&spear310_shirq_ras2,
96 	&spear310_shirq_ras3,
97 	&spear310_shirq_intrcomm_ras,
98 };
99 
100 /* spear320 shared irq registers offsets and masks */
101 #define SPEAR320_INT_STS_MASK_REG		0x04
102 #define SPEAR320_INT_CLR_MASK_REG		0x04
103 #define SPEAR320_INT_ENB_MASK_REG		0x08
104 
105 static struct spear_shirq spear320_shirq_ras1 = {
106 	.irq_nr = 3,
107 	.irq_bit_off = 7,
108 	.regs = {
109 		.enb_reg = -1,
110 		.status_reg = SPEAR320_INT_STS_MASK_REG,
111 		.clear_reg = SPEAR320_INT_CLR_MASK_REG,
112 		.reset_to_clear = 1,
113 	},
114 };
115 
116 static struct spear_shirq spear320_shirq_ras2 = {
117 	.irq_nr = 1,
118 	.irq_bit_off = 10,
119 	.regs = {
120 		.enb_reg = -1,
121 		.status_reg = SPEAR320_INT_STS_MASK_REG,
122 		.clear_reg = SPEAR320_INT_CLR_MASK_REG,
123 		.reset_to_clear = 1,
124 	},
125 };
126 
127 static struct spear_shirq spear320_shirq_ras3 = {
128 	.irq_nr = 3,
129 	.irq_bit_off = 0,
130 	.invalid_irq = 1,
131 	.regs = {
132 		.enb_reg = SPEAR320_INT_ENB_MASK_REG,
133 		.reset_to_enb = 1,
134 		.status_reg = SPEAR320_INT_STS_MASK_REG,
135 		.clear_reg = SPEAR320_INT_CLR_MASK_REG,
136 		.reset_to_clear = 1,
137 	},
138 };
139 
140 static struct spear_shirq spear320_shirq_intrcomm_ras = {
141 	.irq_nr = 11,
142 	.irq_bit_off = 11,
143 	.regs = {
144 		.enb_reg = -1,
145 		.status_reg = SPEAR320_INT_STS_MASK_REG,
146 		.clear_reg = SPEAR320_INT_CLR_MASK_REG,
147 		.reset_to_clear = 1,
148 	},
149 };
150 
151 static struct spear_shirq *spear320_shirq_blocks[] = {
152 	&spear320_shirq_ras3,
153 	&spear320_shirq_ras1,
154 	&spear320_shirq_ras2,
155 	&spear320_shirq_intrcomm_ras,
156 };
157 
158 static void shirq_irq_mask_unmask(struct irq_data *d, bool mask)
159 {
160 	struct spear_shirq *shirq = irq_data_get_irq_chip_data(d);
161 	u32 val, offset = d->irq - shirq->irq_base;
162 	unsigned long flags;
163 
164 	if (shirq->regs.enb_reg == -1)
165 		return;
166 
167 	spin_lock_irqsave(&lock, flags);
168 	val = readl(shirq->base + shirq->regs.enb_reg);
169 
170 	if (mask ^ shirq->regs.reset_to_enb)
171 		val &= ~(0x1 << shirq->irq_bit_off << offset);
172 	else
173 		val |= 0x1 << shirq->irq_bit_off << offset;
174 
175 	writel(val, shirq->base + shirq->regs.enb_reg);
176 	spin_unlock_irqrestore(&lock, flags);
177 
178 }
179 
180 static void shirq_irq_mask(struct irq_data *d)
181 {
182 	shirq_irq_mask_unmask(d, 1);
183 }
184 
185 static void shirq_irq_unmask(struct irq_data *d)
186 {
187 	shirq_irq_mask_unmask(d, 0);
188 }
189 
190 static struct irq_chip shirq_chip = {
191 	.name		= "spear-shirq",
192 	.irq_ack	= shirq_irq_mask,
193 	.irq_mask	= shirq_irq_mask,
194 	.irq_unmask	= shirq_irq_unmask,
195 };
196 
197 static void shirq_handler(unsigned irq, struct irq_desc *desc)
198 {
199 	u32 i, j, val, mask, tmp;
200 	struct irq_chip *chip;
201 	struct spear_shirq *shirq = irq_get_handler_data(irq);
202 
203 	chip = irq_get_chip(irq);
204 	chip->irq_ack(&desc->irq_data);
205 
206 	mask = ((0x1 << shirq->irq_nr) - 1) << shirq->irq_bit_off;
207 	while ((val = readl(shirq->base + shirq->regs.status_reg) &
208 				mask)) {
209 
210 		val >>= shirq->irq_bit_off;
211 		for (i = 0, j = 1; i < shirq->irq_nr; i++, j <<= 1) {
212 
213 			if (!(j & val))
214 				continue;
215 
216 			generic_handle_irq(shirq->irq_base + i);
217 
218 			/* clear interrupt */
219 			if (shirq->regs.clear_reg == -1)
220 				continue;
221 
222 			tmp = readl(shirq->base + shirq->regs.clear_reg);
223 			if (shirq->regs.reset_to_clear)
224 				tmp &= ~(j << shirq->irq_bit_off);
225 			else
226 				tmp |= (j << shirq->irq_bit_off);
227 			writel(tmp, shirq->base + shirq->regs.clear_reg);
228 		}
229 	}
230 	chip->irq_unmask(&desc->irq_data);
231 }
232 
233 static void __init spear_shirq_register(struct spear_shirq *shirq)
234 {
235 	int i;
236 
237 	if (shirq->invalid_irq)
238 		return;
239 
240 	irq_set_chained_handler(shirq->irq, shirq_handler);
241 	for (i = 0; i < shirq->irq_nr; i++) {
242 		irq_set_chip_and_handler(shirq->irq_base + i,
243 					 &shirq_chip, handle_simple_irq);
244 		set_irq_flags(shirq->irq_base + i, IRQF_VALID);
245 		irq_set_chip_data(shirq->irq_base + i, shirq);
246 	}
247 
248 	irq_set_handler_data(shirq->irq, shirq);
249 }
250 
251 static int __init shirq_init(struct spear_shirq **shirq_blocks, int block_nr,
252 		struct device_node *np)
253 {
254 	int i, irq_base, hwirq = 0, irq_nr = 0;
255 	static struct irq_domain *shirq_domain;
256 	void __iomem *base;
257 
258 	base = of_iomap(np, 0);
259 	if (!base) {
260 		pr_err("%s: failed to map shirq registers\n", __func__);
261 		return -ENXIO;
262 	}
263 
264 	for (i = 0; i < block_nr; i++)
265 		irq_nr += shirq_blocks[i]->irq_nr;
266 
267 	irq_base = irq_alloc_descs(-1, 0, irq_nr, 0);
268 	if (IS_ERR_VALUE(irq_base)) {
269 		pr_err("%s: irq desc alloc failed\n", __func__);
270 		goto err_unmap;
271 	}
272 
273 	shirq_domain = irq_domain_add_legacy(np, irq_nr, irq_base, 0,
274 			&irq_domain_simple_ops, NULL);
275 	if (WARN_ON(!shirq_domain)) {
276 		pr_warn("%s: irq domain init failed\n", __func__);
277 		goto err_free_desc;
278 	}
279 
280 	for (i = 0; i < block_nr; i++) {
281 		shirq_blocks[i]->base = base;
282 		shirq_blocks[i]->irq_base = irq_find_mapping(shirq_domain,
283 				hwirq);
284 		shirq_blocks[i]->irq = irq_of_parse_and_map(np, i);
285 
286 		spear_shirq_register(shirq_blocks[i]);
287 		hwirq += shirq_blocks[i]->irq_nr;
288 	}
289 
290 	return 0;
291 
292 err_free_desc:
293 	irq_free_descs(irq_base, irq_nr);
294 err_unmap:
295 	iounmap(base);
296 	return -ENXIO;
297 }
298 
299 int __init spear300_shirq_of_init(struct device_node *np,
300 		struct device_node *parent)
301 {
302 	return shirq_init(spear300_shirq_blocks,
303 			ARRAY_SIZE(spear300_shirq_blocks), np);
304 }
305 IRQCHIP_DECLARE(spear300_shirq, "st,spear300-shirq", spear300_shirq_of_init);
306 
307 int __init spear310_shirq_of_init(struct device_node *np,
308 		struct device_node *parent)
309 {
310 	return shirq_init(spear310_shirq_blocks,
311 			ARRAY_SIZE(spear310_shirq_blocks), np);
312 }
313 IRQCHIP_DECLARE(spear310_shirq, "st,spear310-shirq", spear310_shirq_of_init);
314 
315 int __init spear320_shirq_of_init(struct device_node *np,
316 		struct device_node *parent)
317 {
318 	return shirq_init(spear320_shirq_blocks,
319 			ARRAY_SIZE(spear320_shirq_blocks), np);
320 }
321 IRQCHIP_DECLARE(spear320_shirq, "st,spear320-shirq", spear320_shirq_of_init);
322