xref: /linux/drivers/net/ethernet/hisilicon/hns_mdio.c (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
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/mfd/syscon.h>
15 #include <linux/module.h>
16 #include <linux/mutex.h>
17 #include <linux/netdevice.h>
18 #include <linux/of_address.h>
19 #include <linux/of.h>
20 #include <linux/of_mdio.h>
21 #include <linux/of_platform.h>
22 #include <linux/phy.h>
23 #include <linux/platform_device.h>
24 #include <linux/regmap.h>
25 #include <linux/spinlock_types.h>
26 
27 #define MDIO_DRV_NAME "Hi-HNS_MDIO"
28 #define MDIO_BUS_NAME "Hisilicon MII Bus"
29 #define MDIO_DRV_VERSION "1.3.0"
30 #define MDIO_COPYRIGHT "Copyright(c) 2015 Huawei Corporation."
31 #define MDIO_DRV_STRING MDIO_BUS_NAME
32 #define MDIO_DEFAULT_DEVICE_DESCR MDIO_BUS_NAME
33 
34 #define MDIO_CTL_DEV_ADDR(x)	(x & 0x1f)
35 #define MDIO_CTL_PORT_ADDR(x)	((x & 0x1f) << 5)
36 
37 #define MDIO_TIMEOUT			1000000
38 
39 struct hns_mdio_device {
40 	void *vbase;		/* mdio reg base address */
41 	struct regmap *subctrl_vbase;
42 };
43 
44 /* mdio reg */
45 #define MDIO_COMMAND_REG		0x0
46 #define MDIO_ADDR_REG			0x4
47 #define MDIO_WDATA_REG			0x8
48 #define MDIO_RDATA_REG			0xc
49 #define MDIO_STA_REG			0x10
50 
51 /* cfg phy bit map */
52 #define MDIO_CMD_DEVAD_M	0x1f
53 #define MDIO_CMD_DEVAD_S	0
54 #define MDIO_CMD_PRTAD_M	0x1f
55 #define MDIO_CMD_PRTAD_S	5
56 #define MDIO_CMD_OP_M		0x3
57 #define MDIO_CMD_OP_S		10
58 #define MDIO_CMD_ST_M		0x3
59 #define MDIO_CMD_ST_S		12
60 #define MDIO_CMD_START_B	14
61 
62 #define MDIO_ADDR_DATA_M	0xffff
63 #define MDIO_ADDR_DATA_S	0
64 
65 #define MDIO_WDATA_DATA_M	0xffff
66 #define MDIO_WDATA_DATA_S	0
67 
68 #define MDIO_RDATA_DATA_M	0xffff
69 #define MDIO_RDATA_DATA_S	0
70 
71 #define MDIO_STATE_STA_B	0
72 
73 enum mdio_st_clause {
74 	MDIO_ST_CLAUSE_45 = 0,
75 	MDIO_ST_CLAUSE_22
76 };
77 
78 enum mdio_c22_op_seq {
79 	MDIO_C22_WRITE = 1,
80 	MDIO_C22_READ = 2
81 };
82 
83 enum mdio_c45_op_seq {
84 	MDIO_C45_WRITE_ADDR = 0,
85 	MDIO_C45_WRITE_DATA,
86 	MDIO_C45_READ_INCREMENT,
87 	MDIO_C45_READ
88 };
89 
90 /* peri subctrl reg */
91 #define MDIO_SC_CLK_EN		0x338
92 #define MDIO_SC_CLK_DIS		0x33C
93 #define MDIO_SC_RESET_REQ	0xA38
94 #define MDIO_SC_RESET_DREQ	0xA3C
95 #define MDIO_SC_CTRL		0x2010
96 #define MDIO_SC_CLK_ST		0x531C
97 #define MDIO_SC_RESET_ST	0x5A1C
98 
99 static void mdio_write_reg(void *base, u32 reg, u32 value)
100 {
101 	u8 __iomem *reg_addr = (u8 __iomem *)base;
102 
103 	writel_relaxed(value, reg_addr + reg);
104 }
105 
106 #define MDIO_WRITE_REG(a, reg, value) \
107 	mdio_write_reg((a)->vbase, (reg), (value))
108 
109 static u32 mdio_read_reg(void *base, u32 reg)
110 {
111 	u8 __iomem *reg_addr = (u8 __iomem *)base;
112 
113 	return readl_relaxed(reg_addr + reg);
114 }
115 
116 #define mdio_set_field(origin, mask, shift, val) \
117 	do { \
118 		(origin) &= (~((mask) << (shift))); \
119 		(origin) |= (((val) & (mask)) << (shift)); \
120 	} while (0)
121 
122 #define mdio_get_field(origin, mask, shift) (((origin) >> (shift)) & (mask))
123 
124 static void mdio_set_reg_field(void *base, u32 reg, u32 mask, u32 shift,
125 			       u32 val)
126 {
127 	u32 origin = mdio_read_reg(base, reg);
128 
129 	mdio_set_field(origin, mask, shift, val);
130 	mdio_write_reg(base, reg, origin);
131 }
132 
133 #define MDIO_SET_REG_FIELD(dev, reg, mask, shift, val) \
134 	mdio_set_reg_field((dev)->vbase, (reg), (mask), (shift), (val))
135 
136 static u32 mdio_get_reg_field(void *base, u32 reg, u32 mask, u32 shift)
137 {
138 	u32 origin;
139 
140 	origin = mdio_read_reg(base, reg);
141 	return mdio_get_field(origin, mask, shift);
142 }
143 
144 #define MDIO_GET_REG_FIELD(dev, reg, mask, shift) \
145 		mdio_get_reg_field((dev)->vbase, (reg), (mask), (shift))
146 
147 #define MDIO_GET_REG_BIT(dev, reg, bit) \
148 		mdio_get_reg_field((dev)->vbase, (reg), 0x1ull, (bit))
149 
150 #define MDIO_CHECK_SET_ST	1
151 #define MDIO_CHECK_CLR_ST	0
152 
153 static int mdio_sc_cfg_reg_write(struct hns_mdio_device *mdio_dev,
154 				 u32 cfg_reg, u32 set_val,
155 				 u32 st_reg, u32 st_msk, u8 check_st)
156 {
157 	u32 time_cnt;
158 	u32 reg_value;
159 
160 	regmap_write(mdio_dev->subctrl_vbase, cfg_reg, set_val);
161 
162 	for (time_cnt = MDIO_TIMEOUT; time_cnt; time_cnt--) {
163 		regmap_read(mdio_dev->subctrl_vbase, st_reg, &reg_value);
164 		reg_value &= st_msk;
165 		if ((!!check_st) == (!!reg_value))
166 			break;
167 	}
168 
169 	if ((!!check_st) != (!!reg_value))
170 		return -EBUSY;
171 
172 	return 0;
173 }
174 
175 static int hns_mdio_wait_ready(struct mii_bus *bus)
176 {
177 	struct hns_mdio_device *mdio_dev = bus->priv;
178 	int i;
179 	u32 cmd_reg_value = 1;
180 
181 	/* waitting for MDIO_COMMAND_REG 's mdio_start==0 */
182 	/* after that can do read or write*/
183 	for (i = 0; cmd_reg_value; i++) {
184 		cmd_reg_value = MDIO_GET_REG_BIT(mdio_dev,
185 						 MDIO_COMMAND_REG,
186 						 MDIO_CMD_START_B);
187 		if (i == MDIO_TIMEOUT)
188 			return -ETIMEDOUT;
189 	}
190 
191 	return 0;
192 }
193 
194 static void hns_mdio_cmd_write(struct hns_mdio_device *mdio_dev,
195 			       u8 is_c45, u8 op, u8 phy_id, u16 cmd)
196 {
197 	u32 cmd_reg_value;
198 	u8 st = is_c45 ? MDIO_ST_CLAUSE_45 : MDIO_ST_CLAUSE_22;
199 
200 	cmd_reg_value = st << MDIO_CMD_ST_S;
201 	cmd_reg_value |= op << MDIO_CMD_OP_S;
202 	cmd_reg_value |=
203 		(phy_id & MDIO_CMD_PRTAD_M) << MDIO_CMD_PRTAD_S;
204 	cmd_reg_value |= (cmd & MDIO_CMD_DEVAD_M) << MDIO_CMD_DEVAD_S;
205 	cmd_reg_value |= 1 << MDIO_CMD_START_B;
206 
207 	MDIO_WRITE_REG(mdio_dev, MDIO_COMMAND_REG, cmd_reg_value);
208 }
209 
210 /**
211  * hns_mdio_write - access phy register
212  * @bus: mdio bus
213  * @phy_id: phy id
214  * @regnum: register num
215  * @value: register value
216  *
217  * Return 0 on success, negative on failure
218  */
219 static int hns_mdio_write(struct mii_bus *bus,
220 			  int phy_id, int regnum, u16 data)
221 {
222 	int ret;
223 	struct hns_mdio_device *mdio_dev = (struct hns_mdio_device *)bus->priv;
224 	u8 devad = ((regnum >> 16) & 0x1f);
225 	u8 is_c45 = !!(regnum & MII_ADDR_C45);
226 	u16 reg = (u16)(regnum & 0xffff);
227 	u8 op;
228 	u16 cmd_reg_cfg;
229 
230 	dev_dbg(&bus->dev, "mdio write %s,base is %p\n",
231 		bus->id, mdio_dev->vbase);
232 	dev_dbg(&bus->dev, "phy id=%d, is_c45=%d, devad=%d, reg=%#x, write data=%d\n",
233 		phy_id, is_c45, devad, reg, data);
234 
235 	/* wait for ready */
236 	ret = hns_mdio_wait_ready(bus);
237 	if (ret) {
238 		dev_err(&bus->dev, "MDIO bus is busy\n");
239 		return ret;
240 	}
241 
242 	if (!is_c45) {
243 		cmd_reg_cfg = reg;
244 		op = MDIO_C22_WRITE;
245 	} else {
246 		/* config the cmd-reg to write addr*/
247 		MDIO_SET_REG_FIELD(mdio_dev, MDIO_ADDR_REG, MDIO_ADDR_DATA_M,
248 				   MDIO_ADDR_DATA_S, reg);
249 
250 		hns_mdio_cmd_write(mdio_dev, is_c45,
251 				   MDIO_C45_WRITE_ADDR, phy_id, devad);
252 
253 		/* check for read or write opt is finished */
254 		ret = hns_mdio_wait_ready(bus);
255 		if (ret) {
256 			dev_err(&bus->dev, "MDIO bus is busy\n");
257 			return ret;
258 		}
259 
260 		/* config the data needed writing */
261 		cmd_reg_cfg = devad;
262 		op = MDIO_C45_WRITE_ADDR;
263 	}
264 
265 	MDIO_SET_REG_FIELD(mdio_dev, MDIO_WDATA_REG, MDIO_WDATA_DATA_M,
266 			   MDIO_WDATA_DATA_S, data);
267 
268 	hns_mdio_cmd_write(mdio_dev, is_c45, op, phy_id, cmd_reg_cfg);
269 
270 	return 0;
271 }
272 
273 /**
274  * hns_mdio_read - access phy register
275  * @bus: mdio bus
276  * @phy_id: phy id
277  * @regnum: register num
278  * @value: register value
279  *
280  * Return phy register value
281  */
282 static int hns_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
283 {
284 	int ret;
285 	u16 reg_val = 0;
286 	u8 devad = ((regnum >> 16) & 0x1f);
287 	u8 is_c45 = !!(regnum & MII_ADDR_C45);
288 	u16 reg = (u16)(regnum & 0xffff);
289 	struct hns_mdio_device *mdio_dev = (struct hns_mdio_device *)bus->priv;
290 
291 	dev_dbg(&bus->dev, "mdio read %s,base is %p\n",
292 		bus->id, mdio_dev->vbase);
293 	dev_dbg(&bus->dev, "phy id=%d, is_c45=%d, devad=%d, reg=%#x!\n",
294 		phy_id, is_c45, devad, reg);
295 
296 	/* Step 1: wait for ready */
297 	ret = hns_mdio_wait_ready(bus);
298 	if (ret) {
299 		dev_err(&bus->dev, "MDIO bus is busy\n");
300 		return ret;
301 	}
302 
303 	if (!is_c45) {
304 		hns_mdio_cmd_write(mdio_dev, is_c45,
305 				   MDIO_C22_READ, phy_id, reg);
306 	} else {
307 		MDIO_SET_REG_FIELD(mdio_dev, MDIO_ADDR_REG, MDIO_ADDR_DATA_M,
308 				   MDIO_ADDR_DATA_S, reg);
309 
310 		/* Step 2; config the cmd-reg to write addr*/
311 		hns_mdio_cmd_write(mdio_dev, is_c45,
312 				   MDIO_C45_WRITE_ADDR, phy_id, devad);
313 
314 		/* Step 3: check for read or write opt is finished */
315 		ret = hns_mdio_wait_ready(bus);
316 		if (ret) {
317 			dev_err(&bus->dev, "MDIO bus is busy\n");
318 			return ret;
319 		}
320 
321 		hns_mdio_cmd_write(mdio_dev, is_c45,
322 				   MDIO_C45_WRITE_ADDR, phy_id, devad);
323 	}
324 
325 	/* Step 5: waitting for MDIO_COMMAND_REG 's mdio_start==0,*/
326 	/* check for read or write opt is finished */
327 	ret = hns_mdio_wait_ready(bus);
328 	if (ret) {
329 		dev_err(&bus->dev, "MDIO bus is busy\n");
330 		return ret;
331 	}
332 
333 	reg_val = MDIO_GET_REG_BIT(mdio_dev, MDIO_STA_REG, MDIO_STATE_STA_B);
334 	if (reg_val) {
335 		dev_err(&bus->dev, " ERROR! MDIO Read failed!\n");
336 		return -EBUSY;
337 	}
338 
339 	/* Step 6; get out data*/
340 	reg_val = (u16)MDIO_GET_REG_FIELD(mdio_dev, MDIO_RDATA_REG,
341 					  MDIO_RDATA_DATA_M, MDIO_RDATA_DATA_S);
342 
343 	return reg_val;
344 }
345 
346 /**
347  * hns_mdio_reset - reset mdio bus
348  * @bus: mdio bus
349  *
350  * Return 0 on success, negative on failure
351  */
352 static int hns_mdio_reset(struct mii_bus *bus)
353 {
354 	struct hns_mdio_device *mdio_dev = (struct hns_mdio_device *)bus->priv;
355 	int ret;
356 
357 	if (!mdio_dev->subctrl_vbase) {
358 		dev_err(&bus->dev, "mdio sys ctl reg has not maped\n");
359 		return -ENODEV;
360 	}
361 
362 	/*1. reset req, and read reset st check*/
363 	ret = mdio_sc_cfg_reg_write(mdio_dev, MDIO_SC_RESET_REQ, 0x1,
364 				    MDIO_SC_RESET_ST, 0x1,
365 				    MDIO_CHECK_SET_ST);
366 	if (ret) {
367 		dev_err(&bus->dev, "MDIO reset fail\n");
368 		return ret;
369 	}
370 
371 	/*2. dis clk, and read clk st check*/
372 	ret = mdio_sc_cfg_reg_write(mdio_dev, MDIO_SC_CLK_DIS,
373 				    0x1, MDIO_SC_CLK_ST, 0x1,
374 				    MDIO_CHECK_CLR_ST);
375 	if (ret) {
376 		dev_err(&bus->dev, "MDIO dis clk fail\n");
377 		return ret;
378 	}
379 
380 	/*3. reset dreq, and read reset st check*/
381 	ret = mdio_sc_cfg_reg_write(mdio_dev, MDIO_SC_RESET_DREQ, 0x1,
382 				    MDIO_SC_RESET_ST, 0x1,
383 				    MDIO_CHECK_CLR_ST);
384 	if (ret) {
385 		dev_err(&bus->dev, "MDIO dis clk fail\n");
386 		return ret;
387 	}
388 
389 	/*4. en clk, and read clk st check*/
390 	ret = mdio_sc_cfg_reg_write(mdio_dev, MDIO_SC_CLK_EN,
391 				    0x1, MDIO_SC_CLK_ST, 0x1,
392 				    MDIO_CHECK_SET_ST);
393 	if (ret)
394 		dev_err(&bus->dev, "MDIO en clk fail\n");
395 
396 	return ret;
397 }
398 
399 /**
400  * hns_mdio_bus_name - get mdio bus name
401  * @name: mdio bus name
402  * @np: mdio device node pointer
403  */
404 static void hns_mdio_bus_name(char *name, struct device_node *np)
405 {
406 	const u32 *addr;
407 	u64 taddr = OF_BAD_ADDR;
408 
409 	addr = of_get_address(np, 0, NULL, NULL);
410 	if (addr)
411 		taddr = of_translate_address(np, addr);
412 
413 	snprintf(name, MII_BUS_ID_SIZE, "%s@%llx", np->name,
414 		 (unsigned long long)taddr);
415 }
416 
417 /**
418  * hns_mdio_probe - probe mdio device
419  * @pdev: mdio platform device
420  *
421  * Return 0 on success, negative on failure
422  */
423 static int hns_mdio_probe(struct platform_device *pdev)
424 {
425 	struct device_node *np;
426 	struct hns_mdio_device *mdio_dev;
427 	struct mii_bus *new_bus;
428 	struct resource *res;
429 	int ret;
430 
431 	if (!pdev) {
432 		dev_err(NULL, "pdev is NULL!\r\n");
433 		return -ENODEV;
434 	}
435 	np = pdev->dev.of_node;
436 	mdio_dev = devm_kzalloc(&pdev->dev, sizeof(*mdio_dev), GFP_KERNEL);
437 	if (!mdio_dev)
438 		return -ENOMEM;
439 
440 	new_bus = devm_mdiobus_alloc(&pdev->dev);
441 	if (!new_bus) {
442 		dev_err(&pdev->dev, "mdiobus_alloc fail!\n");
443 		return -ENOMEM;
444 	}
445 
446 	new_bus->name = MDIO_BUS_NAME;
447 	new_bus->read = hns_mdio_read;
448 	new_bus->write = hns_mdio_write;
449 	new_bus->reset = hns_mdio_reset;
450 	new_bus->priv = mdio_dev;
451 	hns_mdio_bus_name(new_bus->id, np);
452 
453 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
454 	mdio_dev->vbase = devm_ioremap_resource(&pdev->dev, res);
455 	if (IS_ERR(mdio_dev->vbase)) {
456 		ret = PTR_ERR(mdio_dev->vbase);
457 		return ret;
458 	}
459 
460 	mdio_dev->subctrl_vbase =
461 		syscon_node_to_regmap(of_parse_phandle(np, "subctrl-vbase", 0));
462 	if (IS_ERR(mdio_dev->subctrl_vbase)) {
463 		dev_warn(&pdev->dev, "no syscon hisilicon,peri-c-subctrl\n");
464 		mdio_dev->subctrl_vbase = NULL;
465 	}
466 	new_bus->parent = &pdev->dev;
467 	platform_set_drvdata(pdev, new_bus);
468 
469 	ret = of_mdiobus_register(new_bus, np);
470 	if (ret) {
471 		dev_err(&pdev->dev, "Cannot register as MDIO bus!\n");
472 		platform_set_drvdata(pdev, NULL);
473 		return ret;
474 	}
475 
476 	return 0;
477 }
478 
479 /**
480  * hns_mdio_remove - remove mdio device
481  * @pdev: mdio platform device
482  *
483  * Return 0 on success, negative on failure
484  */
485 static int hns_mdio_remove(struct platform_device *pdev)
486 {
487 	struct mii_bus *bus;
488 
489 	bus = platform_get_drvdata(pdev);
490 
491 	mdiobus_unregister(bus);
492 	platform_set_drvdata(pdev, NULL);
493 	return 0;
494 }
495 
496 static const struct of_device_id hns_mdio_match[] = {
497 	{.compatible = "hisilicon,mdio"},
498 	{.compatible = "hisilicon,hns-mdio"},
499 	{}
500 };
501 
502 static struct platform_driver hns_mdio_driver = {
503 	.probe = hns_mdio_probe,
504 	.remove = hns_mdio_remove,
505 	.driver = {
506 		   .name = MDIO_DRV_NAME,
507 		   .of_match_table = hns_mdio_match,
508 		   },
509 };
510 
511 module_platform_driver(hns_mdio_driver);
512 
513 MODULE_LICENSE("GPL");
514 MODULE_AUTHOR("Huawei Tech. Co., Ltd.");
515 MODULE_DESCRIPTION("Hisilicon HNS MDIO driver");
516 MODULE_ALIAS("platform:" MDIO_DRV_NAME);
517