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 
get_mbigen_node_offset(unsigned int nid)67 static inline unsigned int get_mbigen_node_offset(unsigned int nid)
68 {
69 	unsigned int offset = nid * MBIGEN_NODE_OFFSET;
70 
71 	/*
72 	 * To avoid touched clear register in unexpected way, we need to directly
73 	 * skip clear register when access to more than 10 mbigen nodes.
74 	 */
75 	if (nid >= (REG_MBIGEN_CLEAR_OFFSET / MBIGEN_NODE_OFFSET))
76 		offset += MBIGEN_NODE_OFFSET;
77 
78 	return offset;
79 }
80 
get_mbigen_vec_reg(irq_hw_number_t hwirq)81 static inline unsigned int get_mbigen_vec_reg(irq_hw_number_t hwirq)
82 {
83 	unsigned int nid, pin;
84 
85 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
86 	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
87 	pin = hwirq % IRQS_PER_MBIGEN_NODE;
88 
89 	return pin * 4 + get_mbigen_node_offset(nid) + REG_MBIGEN_VEC_OFFSET;
90 }
91 
get_mbigen_type_reg(irq_hw_number_t hwirq,u32 * mask,u32 * addr)92 static inline void get_mbigen_type_reg(irq_hw_number_t hwirq,
93 					u32 *mask, u32 *addr)
94 {
95 	unsigned int nid, irq_ofst, ofst;
96 
97 	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
98 	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
99 	irq_ofst = hwirq % IRQS_PER_MBIGEN_NODE;
100 
101 	*mask = 1 << (irq_ofst % 32);
102 	ofst = irq_ofst / 32 * 4;
103 
104 	*addr = ofst + get_mbigen_node_offset(nid) + REG_MBIGEN_TYPE_OFFSET;
105 }
106 
get_mbigen_clear_reg(irq_hw_number_t hwirq,u32 * mask,u32 * addr)107 static inline void get_mbigen_clear_reg(irq_hw_number_t hwirq,
108 					u32 *mask, u32 *addr)
109 {
110 	unsigned int ofst = (hwirq / 32) * 4;
111 
112 	*mask = 1 << (hwirq % 32);
113 	*addr = ofst + REG_MBIGEN_CLEAR_OFFSET;
114 }
115 
mbigen_eoi_irq(struct irq_data * data)116 static void mbigen_eoi_irq(struct irq_data *data)
117 {
118 	void __iomem *base = data->chip_data;
119 	u32 mask, addr;
120 
121 	get_mbigen_clear_reg(data->hwirq, &mask, &addr);
122 
123 	writel_relaxed(mask, base + addr);
124 
125 	irq_chip_eoi_parent(data);
126 }
127 
mbigen_set_type(struct irq_data * data,unsigned int type)128 static int mbigen_set_type(struct irq_data *data, unsigned int type)
129 {
130 	void __iomem *base = data->chip_data;
131 	u32 mask, addr, val;
132 
133 	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
134 		return -EINVAL;
135 
136 	get_mbigen_type_reg(data->hwirq, &mask, &addr);
137 
138 	val = readl_relaxed(base + addr);
139 
140 	if (type == IRQ_TYPE_LEVEL_HIGH)
141 		val |= mask;
142 	else
143 		val &= ~mask;
144 
145 	writel_relaxed(val, base + addr);
146 
147 	return 0;
148 }
149 
mbigen_write_msi_msg(struct irq_data * d,struct msi_msg * msg)150 static void mbigen_write_msi_msg(struct irq_data *d, struct msi_msg *msg)
151 {
152 	void __iomem *base = d->chip_data;
153 	u32 val;
154 
155 	if (!msg->address_lo && !msg->address_hi)
156 		return;
157 
158 	base += get_mbigen_vec_reg(d->hwirq);
159 	val = readl_relaxed(base);
160 
161 	val &= ~(IRQ_EVENT_ID_MASK << IRQ_EVENT_ID_SHIFT);
162 	val |= (msg->data << IRQ_EVENT_ID_SHIFT);
163 
164 	/* The address of doorbell is encoded in mbigen register by default
165 	 * So,we don't need to program the doorbell address at here
166 	 */
167 	writel_relaxed(val, base);
168 }
169 
mbigen_domain_translate(struct irq_domain * d,struct irq_fwspec * fwspec,unsigned long * hwirq,unsigned int * type)170 static int mbigen_domain_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
171 				   unsigned long *hwirq, 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 
mbigen_domain_set_desc(msi_alloc_info_t * arg,struct msi_desc * desc)195 static void mbigen_domain_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
196 {
197 	arg->desc = desc;
198 	arg->hwirq = (u32)desc->data.icookie.value;
199 }
200 
201 static const struct msi_domain_template mbigen_msi_template = {
202 	.chip = {
203 		.name			= "mbigen-v2",
204 		.irq_mask		= irq_chip_mask_parent,
205 		.irq_unmask		= irq_chip_unmask_parent,
206 		.irq_eoi		= mbigen_eoi_irq,
207 		.irq_set_type		= mbigen_set_type,
208 		.irq_write_msi_msg	= mbigen_write_msi_msg,
209 	},
210 
211 	.ops = {
212 		.set_desc		= mbigen_domain_set_desc,
213 		.msi_translate		= mbigen_domain_translate,
214 	},
215 
216 	.info = {
217 		.bus_token		= DOMAIN_BUS_WIRED_TO_MSI,
218 		.flags			= MSI_FLAG_USE_DEV_FWNODE,
219 	},
220 };
221 
mbigen_create_device_domain(struct device * dev,unsigned int size,struct mbigen_device * mgn_chip)222 static bool mbigen_create_device_domain(struct device *dev, unsigned int size,
223 					struct mbigen_device *mgn_chip)
224 {
225 	if (WARN_ON_ONCE(!dev->msi.domain))
226 		return false;
227 
228 	return msi_create_device_irq_domain(dev, MSI_DEFAULT_DOMAIN,
229 					    &mbigen_msi_template, size,
230 					    NULL, mgn_chip->base);
231 }
232 
mbigen_of_create_domain(struct platform_device * pdev,struct mbigen_device * mgn_chip)233 static int mbigen_of_create_domain(struct platform_device *pdev,
234 				   struct mbigen_device *mgn_chip)
235 {
236 	struct platform_device *child;
237 	u32 num_pins;
238 
239 	for_each_child_of_node_scoped(pdev->dev.of_node, np) {
240 		if (!of_property_read_bool(np, "interrupt-controller"))
241 			continue;
242 
243 		child = of_platform_device_create(np, NULL, NULL);
244 		if (!child)
245 			return -ENOMEM;
246 
247 		if (of_property_read_u32(child->dev.of_node, "num-pins",
248 					 &num_pins) < 0) {
249 			dev_err(&pdev->dev, "No num-pins property\n");
250 			return -EINVAL;
251 		}
252 
253 		if (!mbigen_create_device_domain(&child->dev, num_pins, mgn_chip))
254 			return -ENOMEM;
255 	}
256 
257 	return 0;
258 }
259 
260 #ifdef CONFIG_ACPI
261 static const struct acpi_device_id mbigen_acpi_match[] = {
262 	{ "HISI0152", 0 },
263 	{}
264 };
265 MODULE_DEVICE_TABLE(acpi, mbigen_acpi_match);
266 
mbigen_acpi_create_domain(struct platform_device * pdev,struct mbigen_device * mgn_chip)267 static int mbigen_acpi_create_domain(struct platform_device *pdev,
268 				     struct mbigen_device *mgn_chip)
269 {
270 	u32 num_pins = 0;
271 	int ret;
272 
273 	/*
274 	 * "num-pins" is the total number of interrupt pins implemented in
275 	 * this mbigen instance, and mbigen is an interrupt controller
276 	 * connected to ITS  converting wired interrupts into MSI, so we
277 	 * use "num-pins" to alloc MSI vectors which are needed by client
278 	 * devices connected to it.
279 	 *
280 	 * Here is the DSDT device node used for mbigen in firmware:
281 	 *	Device(MBI0) {
282 	 *		Name(_HID, "HISI0152")
283 	 *		Name(_UID, Zero)
284 	 *		Name(_CRS, ResourceTemplate() {
285 	 *			Memory32Fixed(ReadWrite, 0xa0080000, 0x10000)
286 	 *		})
287 	 *
288 	 *		Name(_DSD, Package () {
289 	 *			ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
290 	 *			Package () {
291 	 *				Package () {"num-pins", 378}
292 	 *			}
293 	 *		})
294 	 *	}
295 	 */
296 	ret = device_property_read_u32(&pdev->dev, "num-pins", &num_pins);
297 	if (ret || num_pins == 0)
298 		return -EINVAL;
299 
300 	if (!mbigen_create_device_domain(&pdev->dev, num_pins, mgn_chip))
301 		return -ENOMEM;
302 
303 	return 0;
304 }
305 #else
mbigen_acpi_create_domain(struct platform_device * pdev,struct mbigen_device * mgn_chip)306 static inline int mbigen_acpi_create_domain(struct platform_device *pdev,
307 					    struct mbigen_device *mgn_chip)
308 {
309 	return -ENODEV;
310 }
311 #endif
312 
mbigen_device_probe(struct platform_device * pdev)313 static int mbigen_device_probe(struct platform_device *pdev)
314 {
315 	struct mbigen_device *mgn_chip;
316 	struct resource *res;
317 	int err;
318 
319 	mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
320 	if (!mgn_chip)
321 		return -ENOMEM;
322 
323 	mgn_chip->pdev = pdev;
324 
325 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
326 	if (!res)
327 		return -EINVAL;
328 
329 	mgn_chip->base = devm_ioremap(&pdev->dev, res->start,
330 				      resource_size(res));
331 	if (!mgn_chip->base) {
332 		dev_err(&pdev->dev, "failed to ioremap %pR\n", res);
333 		return -ENOMEM;
334 	}
335 
336 	if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node)
337 		err = mbigen_of_create_domain(pdev, mgn_chip);
338 	else if (ACPI_COMPANION(&pdev->dev))
339 		err = mbigen_acpi_create_domain(pdev, mgn_chip);
340 	else
341 		err = -EINVAL;
342 
343 	if (err) {
344 		dev_err(&pdev->dev, "Failed to create mbi-gen irqdomain\n");
345 		return err;
346 	}
347 
348 	platform_set_drvdata(pdev, mgn_chip);
349 	return 0;
350 }
351 
352 static const struct of_device_id mbigen_of_match[] = {
353 	{ .compatible = "hisilicon,mbigen-v2" },
354 	{ /* END */ }
355 };
356 MODULE_DEVICE_TABLE(of, mbigen_of_match);
357 
358 static struct platform_driver mbigen_platform_driver = {
359 	.driver = {
360 		.name		= "Hisilicon MBIGEN-V2",
361 		.of_match_table	= mbigen_of_match,
362 		.acpi_match_table = ACPI_PTR(mbigen_acpi_match),
363 		.suppress_bind_attrs = true,
364 	},
365 	.probe			= mbigen_device_probe,
366 };
367 
368 module_platform_driver(mbigen_platform_driver);
369 
370 MODULE_AUTHOR("Jun Ma <majun258@huawei.com>");
371 MODULE_AUTHOR("Yun Wu <wuyun.wu@huawei.com>");
372 MODULE_DESCRIPTION("HiSilicon MBI Generator driver");
373