xref: /openbmc/linux/drivers/irqchip/irq-mbigen.c (revision 82e6fdd6)
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/acpi.h>
20 #include <linux/interrupt.h>
21 #include <linux/irqchip.h>
22 #include <linux/module.h>
23 #include <linux/msi.h>
24 #include <linux/of_address.h>
25 #include <linux/of_irq.h>
26 #include <linux/of_platform.h>
27 #include <linux/platform_device.h>
28 #include <linux/slab.h>
29 
30 /* Interrupt numbers per mbigen node supported */
31 #define IRQS_PER_MBIGEN_NODE		128
32 
33 /* 64 irqs (Pin0-pin63) are reserved for each mbigen chip */
34 #define RESERVED_IRQ_PER_MBIGEN_CHIP	64
35 
36 /* The maximum IRQ pin number of mbigen chip(start from 0) */
37 #define MAXIMUM_IRQ_PIN_NUM		1407
38 
39 /**
40  * In mbigen vector register
41  * bit[21:12]:	event id value
42  * bit[11:0]:	device id
43  */
44 #define IRQ_EVENT_ID_SHIFT		12
45 #define IRQ_EVENT_ID_MASK		0x3ff
46 
47 /* register range of each mbigen node */
48 #define MBIGEN_NODE_OFFSET		0x1000
49 
50 /* offset of vector register in mbigen node */
51 #define REG_MBIGEN_VEC_OFFSET		0x200
52 
53 /**
54  * offset of clear register in mbigen node
55  * This register is used to clear the status
56  * of interrupt
57  */
58 #define REG_MBIGEN_CLEAR_OFFSET		0xa000
59 
60 /**
61  * offset of interrupt type register
62  * This register is used to configure interrupt
63  * trigger type
64  */
65 #define REG_MBIGEN_TYPE_OFFSET		0x0
66 
67 /**
68  * struct mbigen_device - holds the information of mbigen device.
69  *
70  * @pdev:		pointer to the platform device structure of mbigen chip.
71  * @base:		mapped address of this mbigen chip.
72  */
73 struct mbigen_device {
74 	struct platform_device	*pdev;
75 	void __iomem		*base;
76 };
77 
78 static inline unsigned int get_mbigen_vec_reg(irq_hw_number_t hwirq)
79 {
80 	unsigned int nid, pin;
81 
82 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
83 	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
84 	pin = hwirq % IRQS_PER_MBIGEN_NODE;
85 
86 	return pin * 4 + nid * MBIGEN_NODE_OFFSET
87 			+ REG_MBIGEN_VEC_OFFSET;
88 }
89 
90 static inline void get_mbigen_type_reg(irq_hw_number_t hwirq,
91 					u32 *mask, u32 *addr)
92 {
93 	unsigned int nid, irq_ofst, ofst;
94 
95 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
96 	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
97 	irq_ofst = hwirq % IRQS_PER_MBIGEN_NODE;
98 
99 	*mask = 1 << (irq_ofst % 32);
100 	ofst = irq_ofst / 32 * 4;
101 
102 	*addr = ofst + nid * MBIGEN_NODE_OFFSET
103 		+ REG_MBIGEN_TYPE_OFFSET;
104 }
105 
106 static inline void get_mbigen_clear_reg(irq_hw_number_t hwirq,
107 					u32 *mask, u32 *addr)
108 {
109 	unsigned int ofst = (hwirq / 32) * 4;
110 
111 	*mask = 1 << (hwirq % 32);
112 	*addr = ofst + REG_MBIGEN_CLEAR_OFFSET;
113 }
114 
115 static void mbigen_eoi_irq(struct irq_data *data)
116 {
117 	void __iomem *base = data->chip_data;
118 	u32 mask, addr;
119 
120 	get_mbigen_clear_reg(data->hwirq, &mask, &addr);
121 
122 	writel_relaxed(mask, base + addr);
123 
124 	irq_chip_eoi_parent(data);
125 }
126 
127 static int mbigen_set_type(struct irq_data *data, unsigned int type)
128 {
129 	void __iomem *base = data->chip_data;
130 	u32 mask, addr, val;
131 
132 	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
133 		return -EINVAL;
134 
135 	get_mbigen_type_reg(data->hwirq, &mask, &addr);
136 
137 	val = readl_relaxed(base + addr);
138 
139 	if (type == IRQ_TYPE_LEVEL_HIGH)
140 		val |= mask;
141 	else
142 		val &= ~mask;
143 
144 	writel_relaxed(val, base + addr);
145 
146 	return 0;
147 }
148 
149 static struct irq_chip mbigen_irq_chip = {
150 	.name =			"mbigen-v2",
151 	.irq_mask =		irq_chip_mask_parent,
152 	.irq_unmask =		irq_chip_unmask_parent,
153 	.irq_eoi =		mbigen_eoi_irq,
154 	.irq_set_type =		mbigen_set_type,
155 	.irq_set_affinity =	irq_chip_set_affinity_parent,
156 };
157 
158 static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
159 {
160 	struct irq_data *d = irq_get_irq_data(desc->irq);
161 	void __iomem *base = d->chip_data;
162 	u32 val;
163 
164 	base += get_mbigen_vec_reg(d->hwirq);
165 	val = readl_relaxed(base);
166 
167 	val &= ~(IRQ_EVENT_ID_MASK << IRQ_EVENT_ID_SHIFT);
168 	val |= (msg->data << IRQ_EVENT_ID_SHIFT);
169 
170 	/* The address of doorbell is encoded in mbigen register by default
171 	 * So,we don't need to program the doorbell address at here
172 	 */
173 	writel_relaxed(val, base);
174 }
175 
176 static int mbigen_domain_translate(struct irq_domain *d,
177 				    struct irq_fwspec *fwspec,
178 				    unsigned long *hwirq,
179 				    unsigned int *type)
180 {
181 	if (is_of_node(fwspec->fwnode) || is_acpi_device_node(fwspec->fwnode)) {
182 		if (fwspec->param_count != 2)
183 			return -EINVAL;
184 
185 		if ((fwspec->param[0] > MAXIMUM_IRQ_PIN_NUM) ||
186 			(fwspec->param[0] < RESERVED_IRQ_PER_MBIGEN_CHIP))
187 			return -EINVAL;
188 		else
189 			*hwirq = fwspec->param[0];
190 
191 		/* If there is no valid irq type, just use the default type */
192 		if ((fwspec->param[1] == IRQ_TYPE_EDGE_RISING) ||
193 			(fwspec->param[1] == IRQ_TYPE_LEVEL_HIGH))
194 			*type = fwspec->param[1];
195 		else
196 			return -EINVAL;
197 
198 		return 0;
199 	}
200 	return -EINVAL;
201 }
202 
203 static int mbigen_irq_domain_alloc(struct irq_domain *domain,
204 					unsigned int virq,
205 					unsigned int nr_irqs,
206 					void *args)
207 {
208 	struct irq_fwspec *fwspec = args;
209 	irq_hw_number_t hwirq;
210 	unsigned int type;
211 	struct mbigen_device *mgn_chip;
212 	int i, err;
213 
214 	err = mbigen_domain_translate(domain, fwspec, &hwirq, &type);
215 	if (err)
216 		return err;
217 
218 	err = platform_msi_domain_alloc(domain, virq, nr_irqs);
219 	if (err)
220 		return err;
221 
222 	mgn_chip = platform_msi_get_host_data(domain);
223 
224 	for (i = 0; i < nr_irqs; i++)
225 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
226 				      &mbigen_irq_chip, mgn_chip->base);
227 
228 	return 0;
229 }
230 
231 static const struct irq_domain_ops mbigen_domain_ops = {
232 	.translate	= mbigen_domain_translate,
233 	.alloc		= mbigen_irq_domain_alloc,
234 	.free		= irq_domain_free_irqs_common,
235 };
236 
237 static int mbigen_of_create_domain(struct platform_device *pdev,
238 				   struct mbigen_device *mgn_chip)
239 {
240 	struct device *parent;
241 	struct platform_device *child;
242 	struct irq_domain *domain;
243 	struct device_node *np;
244 	u32 num_pins;
245 
246 	for_each_child_of_node(pdev->dev.of_node, np) {
247 		if (!of_property_read_bool(np, "interrupt-controller"))
248 			continue;
249 
250 		parent = platform_bus_type.dev_root;
251 		child = of_platform_device_create(np, NULL, parent);
252 		if (!child)
253 			return -ENOMEM;
254 
255 		if (of_property_read_u32(child->dev.of_node, "num-pins",
256 					 &num_pins) < 0) {
257 			dev_err(&pdev->dev, "No num-pins property\n");
258 			return -EINVAL;
259 		}
260 
261 		domain = platform_msi_create_device_domain(&child->dev, num_pins,
262 							   mbigen_write_msg,
263 							   &mbigen_domain_ops,
264 							   mgn_chip);
265 		if (!domain)
266 			return -ENOMEM;
267 	}
268 
269 	return 0;
270 }
271 
272 #ifdef CONFIG_ACPI
273 static int mbigen_acpi_create_domain(struct platform_device *pdev,
274 				     struct mbigen_device *mgn_chip)
275 {
276 	struct irq_domain *domain;
277 	u32 num_pins = 0;
278 	int ret;
279 
280 	/*
281 	 * "num-pins" is the total number of interrupt pins implemented in
282 	 * this mbigen instance, and mbigen is an interrupt controller
283 	 * connected to ITS  converting wired interrupts into MSI, so we
284 	 * use "num-pins" to alloc MSI vectors which are needed by client
285 	 * devices connected to it.
286 	 *
287 	 * Here is the DSDT device node used for mbigen in firmware:
288 	 *	Device(MBI0) {
289 	 *		Name(_HID, "HISI0152")
290 	 *		Name(_UID, Zero)
291 	 *		Name(_CRS, ResourceTemplate() {
292 	 *			Memory32Fixed(ReadWrite, 0xa0080000, 0x10000)
293 	 *		})
294 	 *
295 	 *		Name(_DSD, Package () {
296 	 *			ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
297 	 *			Package () {
298 	 *				Package () {"num-pins", 378}
299 	 *			}
300 	 *		})
301 	 *	}
302 	 */
303 	ret = device_property_read_u32(&pdev->dev, "num-pins", &num_pins);
304 	if (ret || num_pins == 0)
305 		return -EINVAL;
306 
307 	domain = platform_msi_create_device_domain(&pdev->dev, num_pins,
308 						   mbigen_write_msg,
309 						   &mbigen_domain_ops,
310 						   mgn_chip);
311 	if (!domain)
312 		return -ENOMEM;
313 
314 	return 0;
315 }
316 #else
317 static inline int mbigen_acpi_create_domain(struct platform_device *pdev,
318 					    struct mbigen_device *mgn_chip)
319 {
320 	return -ENODEV;
321 }
322 #endif
323 
324 static int mbigen_device_probe(struct platform_device *pdev)
325 {
326 	struct mbigen_device *mgn_chip;
327 	struct resource *res;
328 	int err;
329 
330 	mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
331 	if (!mgn_chip)
332 		return -ENOMEM;
333 
334 	mgn_chip->pdev = pdev;
335 
336 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
337 	if (!res)
338 		return -EINVAL;
339 
340 	mgn_chip->base = devm_ioremap(&pdev->dev, res->start,
341 				      resource_size(res));
342 	if (!mgn_chip->base) {
343 		dev_err(&pdev->dev, "failed to ioremap %pR\n", res);
344 		return -ENOMEM;
345 	}
346 
347 	if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node)
348 		err = mbigen_of_create_domain(pdev, mgn_chip);
349 	else if (ACPI_COMPANION(&pdev->dev))
350 		err = mbigen_acpi_create_domain(pdev, mgn_chip);
351 	else
352 		err = -EINVAL;
353 
354 	if (err) {
355 		dev_err(&pdev->dev, "Failed to create mbi-gen@%p irqdomain",
356 			mgn_chip->base);
357 		return err;
358 	}
359 
360 	platform_set_drvdata(pdev, mgn_chip);
361 	return 0;
362 }
363 
364 static const struct of_device_id mbigen_of_match[] = {
365 	{ .compatible = "hisilicon,mbigen-v2" },
366 	{ /* END */ }
367 };
368 MODULE_DEVICE_TABLE(of, mbigen_of_match);
369 
370 static const struct acpi_device_id mbigen_acpi_match[] = {
371 	{ "HISI0152", 0 },
372 	{}
373 };
374 MODULE_DEVICE_TABLE(acpi, mbigen_acpi_match);
375 
376 static struct platform_driver mbigen_platform_driver = {
377 	.driver = {
378 		.name		= "Hisilicon MBIGEN-V2",
379 		.of_match_table	= mbigen_of_match,
380 		.acpi_match_table = ACPI_PTR(mbigen_acpi_match),
381 	},
382 	.probe			= mbigen_device_probe,
383 };
384 
385 module_platform_driver(mbigen_platform_driver);
386 
387 MODULE_AUTHOR("Jun Ma <majun258@huawei.com>");
388 MODULE_AUTHOR("Yun Wu <wuyun.wu@huawei.com>");
389 MODULE_LICENSE("GPL");
390 MODULE_DESCRIPTION("Hisilicon MBI Generator driver");
391