xref: /openbmc/linux/drivers/irqchip/irq-mbigen.c (revision a7d48886) 
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015 Hisilicon Limited, All Rights Reserved.
4  * Author: Jun Ma <majun258@huawei.com>
5  * Author: Yun Wu <wuyun.wu@huawei.com>
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/interrupt.h>
10 #include <linux/irqchip.h>
11 #include <linux/module.h>
12 #include <linux/msi.h>
13 #include <linux/of_address.h>
14 #include <linux/of_irq.h>
15 #include <linux/of_platform.h>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
18 
19 /* Interrupt numbers per mbigen node supported */
20 #define IRQS_PER_MBIGEN_NODE		128
21 
22 /* 64 irqs (Pin0-pin63) are reserved for each mbigen chip */
23 #define RESERVED_IRQ_PER_MBIGEN_CHIP	64
24 
25 /* The maximum IRQ pin number of mbigen chip(start from 0) */
26 #define MAXIMUM_IRQ_PIN_NUM		1407
27 
28 /**
29  * In mbigen vector register
30  * bit[21:12]:	event id value
31  * bit[11:0]:	device id
32  */
33 #define IRQ_EVENT_ID_SHIFT		12
34 #define IRQ_EVENT_ID_MASK		0x3ff
35 
36 /* register range of each mbigen node */
37 #define MBIGEN_NODE_OFFSET		0x1000
38 
39 /* offset of vector register in mbigen node */
40 #define REG_MBIGEN_VEC_OFFSET		0x200
41 
42 /**
43  * offset of clear register in mbigen node
44  * This register is used to clear the status
45  * of interrupt
46  */
47 #define REG_MBIGEN_CLEAR_OFFSET		0xa000
48 
49 /**
50  * offset of interrupt type register
51  * This register is used to configure interrupt
52  * trigger type
53  */
54 #define REG_MBIGEN_TYPE_OFFSET		0x0
55 
56 /**
57  * struct mbigen_device - holds the information of mbigen device.
58  *
59  * @pdev:		pointer to the platform device structure of mbigen chip.
60  * @base:		mapped address of this mbigen chip.
61  */
62 struct mbigen_device {
63 	struct platform_device	*pdev;
64 	void __iomem		*base;
65 };
66 
67 static inline unsigned int get_mbigen_vec_reg(irq_hw_number_t hwirq)
68 {
69 	unsigned int nid, pin;
70 
71 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
72 	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
73 	pin = hwirq % IRQS_PER_MBIGEN_NODE;
74 
75 	return pin * 4 + nid * MBIGEN_NODE_OFFSET
76 			+ REG_MBIGEN_VEC_OFFSET;
77 }
78 
79 static inline void get_mbigen_type_reg(irq_hw_number_t hwirq,
80 					u32 *mask, u32 *addr)
81 {
82 	unsigned int nid, irq_ofst, ofst;
83 
84 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
85 	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
86 	irq_ofst = hwirq % IRQS_PER_MBIGEN_NODE;
87 
88 	*mask = 1 << (irq_ofst % 32);
89 	ofst = irq_ofst / 32 * 4;
90 
91 	*addr = ofst + nid * MBIGEN_NODE_OFFSET
92 		+ REG_MBIGEN_TYPE_OFFSET;
93 }
94 
95 static inline void get_mbigen_clear_reg(irq_hw_number_t hwirq,
96 					u32 *mask, u32 *addr)
97 {
98 	unsigned int ofst = (hwirq / 32) * 4;
99 
100 	*mask = 1 << (hwirq % 32);
101 	*addr = ofst + REG_MBIGEN_CLEAR_OFFSET;
102 }
103 
104 static void mbigen_eoi_irq(struct irq_data *data)
105 {
106 	void __iomem *base = data->chip_data;
107 	u32 mask, addr;
108 
109 	get_mbigen_clear_reg(data->hwirq, &mask, &addr);
110 
111 	writel_relaxed(mask, base + addr);
112 
113 	irq_chip_eoi_parent(data);
114 }
115 
116 static int mbigen_set_type(struct irq_data *data, unsigned int type)
117 {
118 	void __iomem *base = data->chip_data;
119 	u32 mask, addr, val;
120 
121 	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
122 		return -EINVAL;
123 
124 	get_mbigen_type_reg(data->hwirq, &mask, &addr);
125 
126 	val = readl_relaxed(base + addr);
127 
128 	if (type == IRQ_TYPE_LEVEL_HIGH)
129 		val |= mask;
130 	else
131 		val &= ~mask;
132 
133 	writel_relaxed(val, base + addr);
134 
135 	return 0;
136 }
137 
138 static struct irq_chip mbigen_irq_chip = {
139 	.name =			"mbigen-v2",
140 	.irq_mask =		irq_chip_mask_parent,
141 	.irq_unmask =		irq_chip_unmask_parent,
142 	.irq_eoi =		mbigen_eoi_irq,
143 	.irq_set_type =		mbigen_set_type,
144 	.irq_set_affinity =	irq_chip_set_affinity_parent,
145 };
146 
147 static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
148 {
149 	struct irq_data *d = irq_get_irq_data(desc->irq);
150 	void __iomem *base = d->chip_data;
151 	u32 val;
152 
153 	if (!msg->address_lo && !msg->address_hi)
154 		return;
155 
156 	base += get_mbigen_vec_reg(d->hwirq);
157 	val = readl_relaxed(base);
158 
159 	val &= ~(IRQ_EVENT_ID_MASK << IRQ_EVENT_ID_SHIFT);
160 	val |= (msg->data << IRQ_EVENT_ID_SHIFT);
161 
162 	/* The address of doorbell is encoded in mbigen register by default
163 	 * So,we don't need to program the doorbell address at here
164 	 */
165 	writel_relaxed(val, base);
166 }
167 
168 static int mbigen_domain_translate(struct irq_domain *d,
169 				    struct irq_fwspec *fwspec,
170 				    unsigned long *hwirq,
171 				    unsigned int *type)
172 {
173 	if (is_of_node(fwspec->fwnode) || is_acpi_device_node(fwspec->fwnode)) {
174 		if (fwspec->param_count != 2)
175 			return -EINVAL;
176 
177 		if ((fwspec->param[0] > MAXIMUM_IRQ_PIN_NUM) ||
178 			(fwspec->param[0] < RESERVED_IRQ_PER_MBIGEN_CHIP))
179 			return -EINVAL;
180 		else
181 			*hwirq = fwspec->param[0];
182 
183 		/* If there is no valid irq type, just use the default type */
184 		if ((fwspec->param[1] == IRQ_TYPE_EDGE_RISING) ||
185 			(fwspec->param[1] == IRQ_TYPE_LEVEL_HIGH))
186 			*type = fwspec->param[1];
187 		else
188 			return -EINVAL;
189 
190 		return 0;
191 	}
192 	return -EINVAL;
193 }
194 
195 static int mbigen_irq_domain_alloc(struct irq_domain *domain,
196 					unsigned int virq,
197 					unsigned int nr_irqs,
198 					void *args)
199 {
200 	struct irq_fwspec *fwspec = args;
201 	irq_hw_number_t hwirq;
202 	unsigned int type;
203 	struct mbigen_device *mgn_chip;
204 	int i, err;
205 
206 	err = mbigen_domain_translate(domain, fwspec, &hwirq, &type);
207 	if (err)
208 		return err;
209 
210 	err = platform_msi_domain_alloc(domain, virq, nr_irqs);
211 	if (err)
212 		return err;
213 
214 	mgn_chip = platform_msi_get_host_data(domain);
215 
216 	for (i = 0; i < nr_irqs; i++)
217 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
218 				      &mbigen_irq_chip, mgn_chip->base);
219 
220 	return 0;
221 }
222 
223 static void mbigen_irq_domain_free(struct irq_domain *domain, unsigned int virq,
224 				   unsigned int nr_irqs)
225 {
226 	platform_msi_domain_free(domain, virq, nr_irqs);
227 }
228 
229 static const struct irq_domain_ops mbigen_domain_ops = {
230 	.translate	= mbigen_domain_translate,
231 	.alloc		= mbigen_irq_domain_alloc,
232 	.free		= mbigen_irq_domain_free,
233 };
234 
235 static int mbigen_of_create_domain(struct platform_device *pdev,
236 				   struct mbigen_device *mgn_chip)
237 {
238 	struct device *parent;
239 	struct platform_device *child;
240 	struct irq_domain *domain;
241 	struct device_node *np;
242 	u32 num_pins;
243 
244 	for_each_child_of_node(pdev->dev.of_node, np) {
245 		if (!of_property_read_bool(np, "interrupt-controller"))
246 			continue;
247 
248 		parent = platform_bus_type.dev_root;
249 		child = of_platform_device_create(np, NULL, parent);
250 		if (!child) {
251 			of_node_put(np);
252 			return -ENOMEM;
253 		}
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 			of_node_put(np);
259 			return -EINVAL;
260 		}
261 
262 		domain = platform_msi_create_device_domain(&child->dev, num_pins,
263 							   mbigen_write_msg,
264 							   &mbigen_domain_ops,
265 							   mgn_chip);
266 		if (!domain) {
267 			of_node_put(np);
268 			return -ENOMEM;
269 		}
270 	}
271 
272 	return 0;
273 }
274 
275 #ifdef CONFIG_ACPI
276 static int mbigen_acpi_create_domain(struct platform_device *pdev,
277 				     struct mbigen_device *mgn_chip)
278 {
279 	struct irq_domain *domain;
280 	u32 num_pins = 0;
281 	int ret;
282 
283 	/*
284 	 * "num-pins" is the total number of interrupt pins implemented in
285 	 * this mbigen instance, and mbigen is an interrupt controller
286 	 * connected to ITS  converting wired interrupts into MSI, so we
287 	 * use "num-pins" to alloc MSI vectors which are needed by client
288 	 * devices connected to it.
289 	 *
290 	 * Here is the DSDT device node used for mbigen in firmware:
291 	 *	Device(MBI0) {
292 	 *		Name(_HID, "HISI0152")
293 	 *		Name(_UID, Zero)
294 	 *		Name(_CRS, ResourceTemplate() {
295 	 *			Memory32Fixed(ReadWrite, 0xa0080000, 0x10000)
296 	 *		})
297 	 *
298 	 *		Name(_DSD, Package () {
299 	 *			ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
300 	 *			Package () {
301 	 *				Package () {"num-pins", 378}
302 	 *			}
303 	 *		})
304 	 *	}
305 	 */
306 	ret = device_property_read_u32(&pdev->dev, "num-pins", &num_pins);
307 	if (ret || num_pins == 0)
308 		return -EINVAL;
309 
310 	domain = platform_msi_create_device_domain(&pdev->dev, num_pins,
311 						   mbigen_write_msg,
312 						   &mbigen_domain_ops,
313 						   mgn_chip);
314 	if (!domain)
315 		return -ENOMEM;
316 
317 	return 0;
318 }
319 #else
320 static inline int mbigen_acpi_create_domain(struct platform_device *pdev,
321 					    struct mbigen_device *mgn_chip)
322 {
323 	return -ENODEV;
324 }
325 #endif
326 
327 static int mbigen_device_probe(struct platform_device *pdev)
328 {
329 	struct mbigen_device *mgn_chip;
330 	struct resource *res;
331 	int err;
332 
333 	mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
334 	if (!mgn_chip)
335 		return -ENOMEM;
336 
337 	mgn_chip->pdev = pdev;
338 
339 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
340 	if (!res)
341 		return -EINVAL;
342 
343 	mgn_chip->base = devm_ioremap(&pdev->dev, res->start,
344 				      resource_size(res));
345 	if (!mgn_chip->base) {
346 		dev_err(&pdev->dev, "failed to ioremap %pR\n", res);
347 		return -ENOMEM;
348 	}
349 
350 	if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node)
351 		err = mbigen_of_create_domain(pdev, mgn_chip);
352 	else if (ACPI_COMPANION(&pdev->dev))
353 		err = mbigen_acpi_create_domain(pdev, mgn_chip);
354 	else
355 		err = -EINVAL;
356 
357 	if (err) {
358 		dev_err(&pdev->dev, "Failed to create mbi-gen irqdomain\n");
359 		return err;
360 	}
361 
362 	platform_set_drvdata(pdev, mgn_chip);
363 	return 0;
364 }
365 
366 static const struct of_device_id mbigen_of_match[] = {
367 	{ .compatible = "hisilicon,mbigen-v2" },
368 	{ /* END */ }
369 };
370 MODULE_DEVICE_TABLE(of, mbigen_of_match);
371 
372 static const struct acpi_device_id mbigen_acpi_match[] = {
373 	{ "HISI0152", 0 },
374 	{}
375 };
376 MODULE_DEVICE_TABLE(acpi, mbigen_acpi_match);
377 
378 static struct platform_driver mbigen_platform_driver = {
379 	.driver = {
380 		.name		= "Hisilicon MBIGEN-V2",
381 		.of_match_table	= mbigen_of_match,
382 		.acpi_match_table = ACPI_PTR(mbigen_acpi_match),
383 		.suppress_bind_attrs = true,
384 	},
385 	.probe			= mbigen_device_probe,
386 };
387 
388 module_platform_driver(mbigen_platform_driver);
389 
390 MODULE_AUTHOR("Jun Ma <majun258@huawei.com>");
391 MODULE_AUTHOR("Yun Wu <wuyun.wu@huawei.com>");
392 MODULE_LICENSE("GPL");
393 MODULE_DESCRIPTION("Hisilicon MBI Generator driver");
394