xref: /linux/drivers/irqchip/irq-mbigen.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
1 /*
2  * Copyright (C) 2015 Hisilicon Limited, All Rights Reserved.
3  * Author: Jun Ma <majun258@huawei.com>
4  * Author: Yun Wu <wuyun.wu@huawei.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #include <linux/interrupt.h>
20 #include <linux/irqchip.h>
21 #include <linux/module.h>
22 #include <linux/msi.h>
23 #include <linux/of_address.h>
24 #include <linux/of_irq.h>
25 #include <linux/of_platform.h>
26 #include <linux/platform_device.h>
27 #include <linux/slab.h>
28 
29 /* Interrupt numbers per mbigen node supported */
30 #define IRQS_PER_MBIGEN_NODE		128
31 
32 /* 64 irqs (Pin0-pin63) are reserved for each mbigen chip */
33 #define RESERVED_IRQ_PER_MBIGEN_CHIP	64
34 
35 /* The maximum IRQ pin number of mbigen chip(start from 0) */
36 #define MAXIMUM_IRQ_PIN_NUM		1407
37 
38 /**
39  * In mbigen vector register
40  * bit[21:12]:	event id value
41  * bit[11:0]:	device id
42  */
43 #define IRQ_EVENT_ID_SHIFT		12
44 #define IRQ_EVENT_ID_MASK		0x3ff
45 
46 /* register range of each mbigen node */
47 #define MBIGEN_NODE_OFFSET		0x1000
48 
49 /* offset of vector register in mbigen node */
50 #define REG_MBIGEN_VEC_OFFSET		0x200
51 
52 /**
53  * offset of clear register in mbigen node
54  * This register is used to clear the status
55  * of interrupt
56  */
57 #define REG_MBIGEN_CLEAR_OFFSET		0xa000
58 
59 /**
60  * offset of interrupt type register
61  * This register is used to configure interrupt
62  * trigger type
63  */
64 #define REG_MBIGEN_TYPE_OFFSET		0x0
65 
66 /**
67  * struct mbigen_device - holds the information of mbigen device.
68  *
69  * @pdev:		pointer to the platform device structure of mbigen chip.
70  * @base:		mapped address of this mbigen chip.
71  */
72 struct mbigen_device {
73 	struct platform_device	*pdev;
74 	void __iomem		*base;
75 };
76 
77 static inline unsigned int get_mbigen_vec_reg(irq_hw_number_t hwirq)
78 {
79 	unsigned int nid, pin;
80 
81 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
82 	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
83 	pin = hwirq % IRQS_PER_MBIGEN_NODE;
84 
85 	return pin * 4 + nid * MBIGEN_NODE_OFFSET
86 			+ REG_MBIGEN_VEC_OFFSET;
87 }
88 
89 static inline void get_mbigen_type_reg(irq_hw_number_t hwirq,
90 					u32 *mask, u32 *addr)
91 {
92 	unsigned int nid, irq_ofst, ofst;
93 
94 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
95 	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
96 	irq_ofst = hwirq % IRQS_PER_MBIGEN_NODE;
97 
98 	*mask = 1 << (irq_ofst % 32);
99 	ofst = irq_ofst / 32 * 4;
100 
101 	*addr = ofst + nid * MBIGEN_NODE_OFFSET
102 		+ REG_MBIGEN_TYPE_OFFSET;
103 }
104 
105 static inline void get_mbigen_clear_reg(irq_hw_number_t hwirq,
106 					u32 *mask, u32 *addr)
107 {
108 	unsigned int ofst;
109 
110 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
111 	ofst = hwirq / 32 * 4;
112 
113 	*mask = 1 << (hwirq % 32);
114 	*addr = ofst + REG_MBIGEN_CLEAR_OFFSET;
115 }
116 
117 static void mbigen_eoi_irq(struct irq_data *data)
118 {
119 	void __iomem *base = data->chip_data;
120 	u32 mask, addr;
121 
122 	get_mbigen_clear_reg(data->hwirq, &mask, &addr);
123 
124 	writel_relaxed(mask, base + addr);
125 
126 	irq_chip_eoi_parent(data);
127 }
128 
129 static int mbigen_set_type(struct irq_data *data, unsigned int type)
130 {
131 	void __iomem *base = data->chip_data;
132 	u32 mask, addr, val;
133 
134 	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
135 		return -EINVAL;
136 
137 	get_mbigen_type_reg(data->hwirq, &mask, &addr);
138 
139 	val = readl_relaxed(base + addr);
140 
141 	if (type == IRQ_TYPE_LEVEL_HIGH)
142 		val |= mask;
143 	else
144 		val &= ~mask;
145 
146 	writel_relaxed(val, base + addr);
147 
148 	return 0;
149 }
150 
151 static struct irq_chip mbigen_irq_chip = {
152 	.name =			"mbigen-v2",
153 	.irq_mask =		irq_chip_mask_parent,
154 	.irq_unmask =		irq_chip_unmask_parent,
155 	.irq_eoi =		mbigen_eoi_irq,
156 	.irq_set_type =		mbigen_set_type,
157 	.irq_set_affinity =	irq_chip_set_affinity_parent,
158 };
159 
160 static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
161 {
162 	struct irq_data *d = irq_get_irq_data(desc->irq);
163 	void __iomem *base = d->chip_data;
164 	u32 val;
165 
166 	base += get_mbigen_vec_reg(d->hwirq);
167 	val = readl_relaxed(base);
168 
169 	val &= ~(IRQ_EVENT_ID_MASK << IRQ_EVENT_ID_SHIFT);
170 	val |= (msg->data << IRQ_EVENT_ID_SHIFT);
171 
172 	/* The address of doorbell is encoded in mbigen register by default
173 	 * So,we don't need to program the doorbell address at here
174 	 */
175 	writel_relaxed(val, base);
176 }
177 
178 static int mbigen_domain_translate(struct irq_domain *d,
179 				    struct irq_fwspec *fwspec,
180 				    unsigned long *hwirq,
181 				    unsigned int *type)
182 {
183 	if (is_of_node(fwspec->fwnode)) {
184 		if (fwspec->param_count != 2)
185 			return -EINVAL;
186 
187 		if ((fwspec->param[0] > MAXIMUM_IRQ_PIN_NUM) ||
188 			(fwspec->param[0] < RESERVED_IRQ_PER_MBIGEN_CHIP))
189 			return -EINVAL;
190 		else
191 			*hwirq = fwspec->param[0];
192 
193 		/* If there is no valid irq type, just use the default type */
194 		if ((fwspec->param[1] == IRQ_TYPE_EDGE_RISING) ||
195 			(fwspec->param[1] == IRQ_TYPE_LEVEL_HIGH))
196 			*type = fwspec->param[1];
197 		else
198 			return -EINVAL;
199 
200 		return 0;
201 	}
202 	return -EINVAL;
203 }
204 
205 static int mbigen_irq_domain_alloc(struct irq_domain *domain,
206 					unsigned int virq,
207 					unsigned int nr_irqs,
208 					void *args)
209 {
210 	struct irq_fwspec *fwspec = args;
211 	irq_hw_number_t hwirq;
212 	unsigned int type;
213 	struct mbigen_device *mgn_chip;
214 	int i, err;
215 
216 	err = mbigen_domain_translate(domain, fwspec, &hwirq, &type);
217 	if (err)
218 		return err;
219 
220 	err = platform_msi_domain_alloc(domain, virq, nr_irqs);
221 	if (err)
222 		return err;
223 
224 	mgn_chip = platform_msi_get_host_data(domain);
225 
226 	for (i = 0; i < nr_irqs; i++)
227 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
228 				      &mbigen_irq_chip, mgn_chip->base);
229 
230 	return 0;
231 }
232 
233 static struct irq_domain_ops mbigen_domain_ops = {
234 	.translate	= mbigen_domain_translate,
235 	.alloc		= mbigen_irq_domain_alloc,
236 	.free		= irq_domain_free_irqs_common,
237 };
238 
239 static int mbigen_device_probe(struct platform_device *pdev)
240 {
241 	struct mbigen_device *mgn_chip;
242 	struct platform_device *child;
243 	struct irq_domain *domain;
244 	struct device_node *np;
245 	struct device *parent;
246 	struct resource *res;
247 	u32 num_pins;
248 
249 	mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
250 	if (!mgn_chip)
251 		return -ENOMEM;
252 
253 	mgn_chip->pdev = pdev;
254 
255 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
256 	mgn_chip->base = devm_ioremap_resource(&pdev->dev, res);
257 	if (IS_ERR(mgn_chip->base))
258 		return PTR_ERR(mgn_chip->base);
259 
260 	for_each_child_of_node(pdev->dev.of_node, np) {
261 		if (!of_property_read_bool(np, "interrupt-controller"))
262 			continue;
263 
264 		parent = platform_bus_type.dev_root;
265 		child = of_platform_device_create(np, NULL, parent);
266 		if (!child)
267 			return -ENOMEM;
268 
269 		if (of_property_read_u32(child->dev.of_node, "num-pins",
270 					 &num_pins) < 0) {
271 			dev_err(&pdev->dev, "No num-pins property\n");
272 			return -EINVAL;
273 		}
274 
275 		domain = platform_msi_create_device_domain(&child->dev, num_pins,
276 							   mbigen_write_msg,
277 							   &mbigen_domain_ops,
278 							   mgn_chip);
279 		if (!domain)
280 			return -ENOMEM;
281 	}
282 
283 	platform_set_drvdata(pdev, mgn_chip);
284 	return 0;
285 }
286 
287 static const struct of_device_id mbigen_of_match[] = {
288 	{ .compatible = "hisilicon,mbigen-v2" },
289 	{ /* END */ }
290 };
291 MODULE_DEVICE_TABLE(of, mbigen_of_match);
292 
293 static struct platform_driver mbigen_platform_driver = {
294 	.driver = {
295 		.name		= "Hisilicon MBIGEN-V2",
296 		.owner		= THIS_MODULE,
297 		.of_match_table	= mbigen_of_match,
298 	},
299 	.probe			= mbigen_device_probe,
300 };
301 
302 module_platform_driver(mbigen_platform_driver);
303 
304 MODULE_AUTHOR("Jun Ma <majun258@huawei.com>");
305 MODULE_AUTHOR("Yun Wu <wuyun.wu@huawei.com>");
306 MODULE_LICENSE("GPL");
307 MODULE_DESCRIPTION("Hisilicon MBI Generator driver");
308