xref: /openbmc/linux/drivers/net/ethernet/hisilicon/hns_mdio.c (revision 372892ec1151c895c7dec362f3246f089690cfc7)
1 /*
2  * Copyright (c) 2014-2015 Hisilicon Limited.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  */
9 
10 #include <linux/errno.h>
11 #include <linux/etherdevice.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/mutex.h>
16 #include <linux/netdevice.h>
17 #include <linux/of_address.h>
18 #include <linux/of.h>
19 #include <linux/of_mdio.h>
20 #include <linux/of_platform.h>
21 #include <linux/phy.h>
22 #include <linux/platform_device.h>
23 #include <linux/spinlock_types.h>
24 
25 #define MDIO_DRV_NAME "Hi-HNS_MDIO"
26 #define MDIO_BUS_NAME "Hisilicon MII Bus"
27 #define MDIO_DRV_VERSION "1.3.0"
28 #define MDIO_COPYRIGHT "Copyright(c) 2015 Huawei Corporation."
29 #define MDIO_DRV_STRING MDIO_BUS_NAME
30 #define MDIO_DEFAULT_DEVICE_DESCR MDIO_BUS_NAME
31 
32 #define MDIO_CTL_DEV_ADDR(x)	(x & 0x1f)
33 #define MDIO_CTL_PORT_ADDR(x)	((x & 0x1f) << 5)
34 
35 #define MDIO_TIMEOUT			1000000
36 
37 struct hns_mdio_device {
38 	void *vbase;		/* mdio reg base address */
39 	void *sys_vbase;
40 };
41 
42 /* mdio reg */
43 #define MDIO_COMMAND_REG		0x0
44 #define MDIO_ADDR_REG			0x4
45 #define MDIO_WDATA_REG			0x8
46 #define MDIO_RDATA_REG			0xc
47 #define MDIO_STA_REG			0x10
48 
49 /* cfg phy bit map */
50 #define MDIO_CMD_DEVAD_M	0x1f
51 #define MDIO_CMD_DEVAD_S	0
52 #define MDIO_CMD_PRTAD_M	0x1f
53 #define MDIO_CMD_PRTAD_S	5
54 #define MDIO_CMD_OP_M		0x3
55 #define MDIO_CMD_OP_S		10
56 #define MDIO_CMD_ST_M		0x3
57 #define MDIO_CMD_ST_S		12
58 #define MDIO_CMD_START_B	14
59 
60 #define MDIO_ADDR_DATA_M	0xffff
61 #define MDIO_ADDR_DATA_S	0
62 
63 #define MDIO_WDATA_DATA_M	0xffff
64 #define MDIO_WDATA_DATA_S	0
65 
66 #define MDIO_RDATA_DATA_M	0xffff
67 #define MDIO_RDATA_DATA_S	0
68 
69 #define MDIO_STATE_STA_B	0
70 
71 enum mdio_st_clause {
72 	MDIO_ST_CLAUSE_45 = 0,
73 	MDIO_ST_CLAUSE_22
74 };
75 
76 enum mdio_c22_op_seq {
77 	MDIO_C22_WRITE = 1,
78 	MDIO_C22_READ = 2
79 };
80 
81 enum mdio_c45_op_seq {
82 	MDIO_C45_WRITE_ADDR = 0,
83 	MDIO_C45_WRITE_DATA,
84 	MDIO_C45_READ_INCREMENT,
85 	MDIO_C45_READ
86 };
87 
88 /* peri subctrl reg */
89 #define MDIO_SC_CLK_EN		0x338
90 #define MDIO_SC_CLK_DIS		0x33C
91 #define MDIO_SC_RESET_REQ	0xA38
92 #define MDIO_SC_RESET_DREQ	0xA3C
93 #define MDIO_SC_CTRL		0x2010
94 #define MDIO_SC_CLK_ST		0x531C
95 #define MDIO_SC_RESET_ST	0x5A1C
96 
97 static void mdio_write_reg(void *base, u32 reg, u32 value)
98 {
99 	u8 __iomem *reg_addr = (u8 __iomem *)base;
100 
101 	writel_relaxed(value, reg_addr + reg);
102 }
103 
104 #define MDIO_WRITE_REG(a, reg, value) \
105 	mdio_write_reg((a)->vbase, (reg), (value))
106 
107 static u32 mdio_read_reg(void *base, u32 reg)
108 {
109 	u8 __iomem *reg_addr = (u8 __iomem *)base;
110 
111 	return readl_relaxed(reg_addr + reg);
112 }
113 
114 #define mdio_set_field(origin, mask, shift, val) \
115 	do { \
116 		(origin) &= (~((mask) << (shift))); \
117 		(origin) |= (((val) & (mask)) << (shift)); \
118 	} while (0)
119 
120 #define mdio_get_field(origin, mask, shift) (((origin) >> (shift)) & (mask))
121 
122 static void mdio_set_reg_field(void *base, u32 reg, u32 mask, u32 shift,
123 			       u32 val)
124 {
125 	u32 origin = mdio_read_reg(base, reg);
126 
127 	mdio_set_field(origin, mask, shift, val);
128 	mdio_write_reg(base, reg, origin);
129 }
130 
131 #define MDIO_SET_REG_FIELD(dev, reg, mask, shift, val) \
132 	mdio_set_reg_field((dev)->vbase, (reg), (mask), (shift), (val))
133 
134 static u32 mdio_get_reg_field(void *base, u32 reg, u32 mask, u32 shift)
135 {
136 	u32 origin;
137 
138 	origin = mdio_read_reg(base, reg);
139 	return mdio_get_field(origin, mask, shift);
140 }
141 
142 #define MDIO_GET_REG_FIELD(dev, reg, mask, shift) \
143 		mdio_get_reg_field((dev)->vbase, (reg), (mask), (shift))
144 
145 #define MDIO_GET_REG_BIT(dev, reg, bit) \
146 		mdio_get_reg_field((dev)->vbase, (reg), 0x1ull, (bit))
147 
148 #define MDIO_CHECK_SET_ST	1
149 #define MDIO_CHECK_CLR_ST	0
150 
151 static int mdio_sc_cfg_reg_write(struct hns_mdio_device *mdio_dev,
152 				 u32 cfg_reg, u32 set_val,
153 				 u32 st_reg, u32 st_msk, u8 check_st)
154 {
155 	u32 time_cnt;
156 	u32 reg_value;
157 
158 	mdio_write_reg((void *)mdio_dev->sys_vbase, cfg_reg, set_val);
159 
160 	for (time_cnt = MDIO_TIMEOUT; time_cnt; time_cnt--) {
161 		reg_value = mdio_read_reg((void *)mdio_dev->sys_vbase, st_reg);
162 		reg_value &= st_msk;
163 		if ((!!check_st) == (!!reg_value))
164 			break;
165 	}
166 
167 	if ((!!check_st) != (!!reg_value))
168 		return -EBUSY;
169 
170 	return 0;
171 }
172 
173 static int hns_mdio_wait_ready(struct mii_bus *bus)
174 {
175 	struct hns_mdio_device *mdio_dev = bus->priv;
176 	int i;
177 	u32 cmd_reg_value = 1;
178 
179 	/* waitting for MDIO_COMMAND_REG 's mdio_start==0 */
180 	/* after that can do read or write*/
181 	for (i = 0; cmd_reg_value; i++) {
182 		cmd_reg_value = MDIO_GET_REG_BIT(mdio_dev,
183 						 MDIO_COMMAND_REG,
184 						 MDIO_CMD_START_B);
185 		if (i == MDIO_TIMEOUT)
186 			return -ETIMEDOUT;
187 	}
188 
189 	return 0;
190 }
191 
192 static void hns_mdio_cmd_write(struct hns_mdio_device *mdio_dev,
193 			       u8 is_c45, u8 op, u8 phy_id, u16 cmd)
194 {
195 	u32 cmd_reg_value;
196 	u8 st = is_c45 ? MDIO_ST_CLAUSE_45 : MDIO_ST_CLAUSE_22;
197 
198 	cmd_reg_value = st << MDIO_CMD_ST_S;
199 	cmd_reg_value |= op << MDIO_CMD_OP_S;
200 	cmd_reg_value |=
201 		(phy_id & MDIO_CMD_PRTAD_M) << MDIO_CMD_PRTAD_S;
202 	cmd_reg_value |= (cmd & MDIO_CMD_DEVAD_M) << MDIO_CMD_DEVAD_S;
203 	cmd_reg_value |= 1 << MDIO_CMD_START_B;
204 
205 	MDIO_WRITE_REG(mdio_dev, MDIO_COMMAND_REG, cmd_reg_value);
206 }
207 
208 /**
209  * hns_mdio_write - access phy register
210  * @bus: mdio bus
211  * @phy_id: phy id
212  * @regnum: register num
213  * @value: register value
214  *
215  * Return 0 on success, negative on failure
216  */
217 static int hns_mdio_write(struct mii_bus *bus,
218 			  int phy_id, int regnum, u16 data)
219 {
220 	int ret;
221 	struct hns_mdio_device *mdio_dev = (struct hns_mdio_device *)bus->priv;
222 	u8 devad = ((regnum >> 16) & 0x1f);
223 	u8 is_c45 = !!(regnum & MII_ADDR_C45);
224 	u16 reg = (u16)(regnum & 0xffff);
225 	u8 op;
226 	u16 cmd_reg_cfg;
227 
228 	dev_dbg(&bus->dev, "mdio write %s,base is %p\n",
229 		bus->id, mdio_dev->vbase);
230 	dev_dbg(&bus->dev, "phy id=%d, is_c45=%d, devad=%d, reg=%#x, write data=%d\n",
231 		phy_id, is_c45, devad, reg, data);
232 
233 	/* wait for ready */
234 	ret = hns_mdio_wait_ready(bus);
235 	if (ret) {
236 		dev_err(&bus->dev, "MDIO bus is busy\n");
237 		return ret;
238 	}
239 
240 	if (!is_c45) {
241 		cmd_reg_cfg = reg;
242 		op = MDIO_C22_WRITE;
243 	} else {
244 		/* config the cmd-reg to write addr*/
245 		MDIO_SET_REG_FIELD(mdio_dev, MDIO_ADDR_REG, MDIO_ADDR_DATA_M,
246 				   MDIO_ADDR_DATA_S, reg);
247 
248 		hns_mdio_cmd_write(mdio_dev, is_c45,
249 				   MDIO_C45_WRITE_ADDR, phy_id, devad);
250 
251 		/* check for read or write opt is finished */
252 		ret = hns_mdio_wait_ready(bus);
253 		if (ret) {
254 			dev_err(&bus->dev, "MDIO bus is busy\n");
255 			return ret;
256 		}
257 
258 		/* config the data needed writing */
259 		cmd_reg_cfg = devad;
260 		op = MDIO_C45_WRITE_ADDR;
261 	}
262 
263 	MDIO_SET_REG_FIELD(mdio_dev, MDIO_WDATA_REG, MDIO_WDATA_DATA_M,
264 			   MDIO_WDATA_DATA_S, data);
265 
266 	hns_mdio_cmd_write(mdio_dev, is_c45, op, phy_id, cmd_reg_cfg);
267 
268 	return 0;
269 }
270 
271 /**
272  * hns_mdio_read - access phy register
273  * @bus: mdio bus
274  * @phy_id: phy id
275  * @regnum: register num
276  * @value: register value
277  *
278  * Return phy register value
279  */
280 static int hns_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
281 {
282 	int ret;
283 	u16 reg_val = 0;
284 	u8 devad = ((regnum >> 16) & 0x1f);
285 	u8 is_c45 = !!(regnum & MII_ADDR_C45);
286 	u16 reg = (u16)(regnum & 0xffff);
287 	struct hns_mdio_device *mdio_dev = (struct hns_mdio_device *)bus->priv;
288 
289 	dev_dbg(&bus->dev, "mdio read %s,base is %p\n",
290 		bus->id, mdio_dev->vbase);
291 	dev_dbg(&bus->dev, "phy id=%d, is_c45=%d, devad=%d, reg=%#x!\n",
292 		phy_id, is_c45, devad, reg);
293 
294 	/* Step 1: wait for ready */
295 	ret = hns_mdio_wait_ready(bus);
296 	if (ret) {
297 		dev_err(&bus->dev, "MDIO bus is busy\n");
298 		return ret;
299 	}
300 
301 	if (!is_c45) {
302 		hns_mdio_cmd_write(mdio_dev, is_c45,
303 				   MDIO_C22_READ, phy_id, reg);
304 	} else {
305 		MDIO_SET_REG_FIELD(mdio_dev, MDIO_ADDR_REG, MDIO_ADDR_DATA_M,
306 				   MDIO_ADDR_DATA_S, reg);
307 
308 		/* Step 2; config the cmd-reg to write addr*/
309 		hns_mdio_cmd_write(mdio_dev, is_c45,
310 				   MDIO_C45_WRITE_ADDR, phy_id, devad);
311 
312 		/* Step 3: check for read or write opt is finished */
313 		ret = hns_mdio_wait_ready(bus);
314 		if (ret) {
315 			dev_err(&bus->dev, "MDIO bus is busy\n");
316 			return ret;
317 		}
318 
319 		hns_mdio_cmd_write(mdio_dev, is_c45,
320 				   MDIO_C45_WRITE_ADDR, phy_id, devad);
321 	}
322 
323 	/* Step 5: waitting for MDIO_COMMAND_REG 's mdio_start==0,*/
324 	/* check for read or write opt is finished */
325 	ret = hns_mdio_wait_ready(bus);
326 	if (ret) {
327 		dev_err(&bus->dev, "MDIO bus is busy\n");
328 		return ret;
329 	}
330 
331 	reg_val = MDIO_GET_REG_BIT(mdio_dev, MDIO_STA_REG, MDIO_STATE_STA_B);
332 	if (reg_val) {
333 		dev_err(&bus->dev, " ERROR! MDIO Read failed!\n");
334 		return -EBUSY;
335 	}
336 
337 	/* Step 6; get out data*/
338 	reg_val = (u16)MDIO_GET_REG_FIELD(mdio_dev, MDIO_RDATA_REG,
339 					  MDIO_RDATA_DATA_M, MDIO_RDATA_DATA_S);
340 
341 	return reg_val;
342 }
343 
344 /**
345  * hns_mdio_reset - reset mdio bus
346  * @bus: mdio bus
347  *
348  * Return 0 on success, negative on failure
349  */
350 static int hns_mdio_reset(struct mii_bus *bus)
351 {
352 	struct hns_mdio_device *mdio_dev = (struct hns_mdio_device *)bus->priv;
353 	int ret;
354 
355 	if (!mdio_dev->sys_vbase) {
356 		dev_err(&bus->dev, "mdio sys ctl reg has not maped\n");
357 		return -ENODEV;
358 	}
359 
360 	/*1. reset req, and read reset st check*/
361 	ret = mdio_sc_cfg_reg_write(mdio_dev, MDIO_SC_RESET_REQ, 0x1,
362 				    MDIO_SC_RESET_ST, 0x1,
363 				    MDIO_CHECK_SET_ST);
364 	if (ret) {
365 		dev_err(&bus->dev, "MDIO reset fail\n");
366 		return ret;
367 	}
368 
369 	/*2. dis clk, and read clk st check*/
370 	ret = mdio_sc_cfg_reg_write(mdio_dev, MDIO_SC_CLK_DIS,
371 				    0x1, MDIO_SC_CLK_ST, 0x1,
372 				    MDIO_CHECK_CLR_ST);
373 	if (ret) {
374 		dev_err(&bus->dev, "MDIO dis clk fail\n");
375 		return ret;
376 	}
377 
378 	/*3. reset dreq, and read reset st check*/
379 	ret = mdio_sc_cfg_reg_write(mdio_dev, MDIO_SC_RESET_DREQ, 0x1,
380 				    MDIO_SC_RESET_ST, 0x1,
381 				    MDIO_CHECK_CLR_ST);
382 	if (ret) {
383 		dev_err(&bus->dev, "MDIO dis clk fail\n");
384 		return ret;
385 	}
386 
387 	/*4. en clk, and read clk st check*/
388 	ret = mdio_sc_cfg_reg_write(mdio_dev, MDIO_SC_CLK_EN,
389 				    0x1, MDIO_SC_CLK_ST, 0x1,
390 				    MDIO_CHECK_SET_ST);
391 	if (ret)
392 		dev_err(&bus->dev, "MDIO en clk fail\n");
393 
394 	return ret;
395 }
396 
397 /**
398  * hns_mdio_bus_name - get mdio bus name
399  * @name: mdio bus name
400  * @np: mdio device node pointer
401  */
402 static void hns_mdio_bus_name(char *name, struct device_node *np)
403 {
404 	const u32 *addr;
405 	u64 taddr = OF_BAD_ADDR;
406 
407 	addr = of_get_address(np, 0, NULL, NULL);
408 	if (addr)
409 		taddr = of_translate_address(np, addr);
410 
411 	snprintf(name, MII_BUS_ID_SIZE, "%s@%llx", np->name,
412 		 (unsigned long long)taddr);
413 }
414 
415 /**
416  * hns_mdio_probe - probe mdio device
417  * @pdev: mdio platform device
418  *
419  * Return 0 on success, negative on failure
420  */
421 static int hns_mdio_probe(struct platform_device *pdev)
422 {
423 	struct device_node *np;
424 	struct hns_mdio_device *mdio_dev;
425 	struct mii_bus *new_bus;
426 	struct resource *res;
427 	int ret;
428 
429 	if (!pdev) {
430 		dev_err(NULL, "pdev is NULL!\r\n");
431 		return -ENODEV;
432 	}
433 	np = pdev->dev.of_node;
434 	mdio_dev = devm_kzalloc(&pdev->dev, sizeof(*mdio_dev), GFP_KERNEL);
435 	if (!mdio_dev)
436 		return -ENOMEM;
437 
438 	new_bus = devm_mdiobus_alloc(&pdev->dev);
439 	if (!new_bus) {
440 		dev_err(&pdev->dev, "mdiobus_alloc fail!\n");
441 		return -ENOMEM;
442 	}
443 
444 	new_bus->name = MDIO_BUS_NAME;
445 	new_bus->read = hns_mdio_read;
446 	new_bus->write = hns_mdio_write;
447 	new_bus->reset = hns_mdio_reset;
448 	new_bus->priv = mdio_dev;
449 	hns_mdio_bus_name(new_bus->id, np);
450 
451 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
452 	mdio_dev->vbase = devm_ioremap_resource(&pdev->dev, res);
453 	if (IS_ERR(mdio_dev->vbase)) {
454 		ret = PTR_ERR(mdio_dev->vbase);
455 		return ret;
456 	}
457 
458 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
459 	mdio_dev->sys_vbase = devm_ioremap_resource(&pdev->dev, res);
460 	if (IS_ERR(mdio_dev->sys_vbase)) {
461 		ret = PTR_ERR(mdio_dev->sys_vbase);
462 		return ret;
463 	}
464 
465 	new_bus->irq = devm_kcalloc(&pdev->dev, PHY_MAX_ADDR,
466 				    sizeof(int), GFP_KERNEL);
467 	if (!new_bus->irq)
468 		return -ENOMEM;
469 
470 	new_bus->parent = &pdev->dev;
471 	platform_set_drvdata(pdev, new_bus);
472 
473 	ret = of_mdiobus_register(new_bus, np);
474 	if (ret) {
475 		dev_err(&pdev->dev, "Cannot register as MDIO bus!\n");
476 		platform_set_drvdata(pdev, NULL);
477 		return ret;
478 	}
479 
480 	return 0;
481 }
482 
483 /**
484  * hns_mdio_remove - remove mdio device
485  * @pdev: mdio platform device
486  *
487  * Return 0 on success, negative on failure
488  */
489 static int hns_mdio_remove(struct platform_device *pdev)
490 {
491 	struct mii_bus *bus;
492 
493 	bus = platform_get_drvdata(pdev);
494 
495 	mdiobus_unregister(bus);
496 	platform_set_drvdata(pdev, NULL);
497 	return 0;
498 }
499 
500 static const struct of_device_id hns_mdio_match[] = {
501 	{.compatible = "hisilicon,mdio"},
502 	{.compatible = "hisilicon,hns-mdio"},
503 	{}
504 };
505 
506 static struct platform_driver hns_mdio_driver = {
507 	.probe = hns_mdio_probe,
508 	.remove = hns_mdio_remove,
509 	.driver = {
510 		   .name = MDIO_DRV_NAME,
511 		   .of_match_table = hns_mdio_match,
512 		   },
513 };
514 
515 module_platform_driver(hns_mdio_driver);
516 
517 MODULE_LICENSE("GPL");
518 MODULE_AUTHOR("Huawei Tech. Co., Ltd.");
519 MODULE_DESCRIPTION("Hisilicon HNS MDIO driver");
520 MODULE_ALIAS("platform:" MDIO_DRV_NAME);
521