1 /*
2  * dwmac-sti.c - STMicroelectronics DWMAC Specific Glue layer
3  *
4  * Copyright (C) 2003-2014 STMicroelectronics (R&D) Limited
5  * Author: Srinivas Kandagatla <srinivas.kandagatla@st.com>
6  * Contributors: Giuseppe Cavallaro <peppe.cavallaro@st.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/platform_device.h>
17 #include <linux/stmmac.h>
18 #include <linux/phy.h>
19 #include <linux/mfd/syscon.h>
20 #include <linux/module.h>
21 #include <linux/regmap.h>
22 #include <linux/clk.h>
23 #include <linux/of.h>
24 #include <linux/of_device.h>
25 #include <linux/of_net.h>
26 
27 #include "stmmac_platform.h"
28 
29 #define DWMAC_125MHZ	125000000
30 #define DWMAC_50MHZ	50000000
31 #define DWMAC_25MHZ	25000000
32 #define DWMAC_2_5MHZ	2500000
33 
34 #define IS_PHY_IF_MODE_RGMII(iface)	(iface == PHY_INTERFACE_MODE_RGMII || \
35 			iface == PHY_INTERFACE_MODE_RGMII_ID || \
36 			iface == PHY_INTERFACE_MODE_RGMII_RXID || \
37 			iface == PHY_INTERFACE_MODE_RGMII_TXID)
38 
39 #define IS_PHY_IF_MODE_GBIT(iface)	(IS_PHY_IF_MODE_RGMII(iface) || \
40 					 iface == PHY_INTERFACE_MODE_GMII)
41 
42 /* STiH4xx register definitions (STiH415/STiH416/STiH407/STiH410 families)
43  *
44  * Below table summarizes the clock requirement and clock sources for
45  * supported phy interface modes with link speeds.
46  * ________________________________________________
47  *|  PHY_MODE	| 1000 Mbit Link | 100 Mbit Link   |
48  * ------------------------------------------------
49  *|	MII	|	n/a	 |	25Mhz	   |
50  *|		|		 |	txclk	   |
51  * ------------------------------------------------
52  *|	GMII	|     125Mhz	 |	25Mhz	   |
53  *|		|  clk-125/txclk |	txclk	   |
54  * ------------------------------------------------
55  *|	RGMII	|     125Mhz	 |	25Mhz	   |
56  *|		|  clk-125/txclk |	clkgen     |
57  *|		|    clkgen	 |		   |
58  * ------------------------------------------------
59  *|	RMII	|	n/a	 |	25Mhz	   |
60  *|		|		 |clkgen/phyclk-in |
61  * ------------------------------------------------
62  *
63  *	  Register Configuration
64  *-------------------------------
65  * src	 |BIT(8)| BIT(7)| BIT(6)|
66  *-------------------------------
67  * txclk |   0	|  n/a	|   1	|
68  *-------------------------------
69  * ck_125|   0	|  n/a	|   0	|
70  *-------------------------------
71  * phyclk|   1	|   0	|  n/a	|
72  *-------------------------------
73  * clkgen|   1	|   1	|  n/a	|
74  *-------------------------------
75  */
76 
77 #define STIH4XX_RETIME_SRC_MASK			GENMASK(8, 6)
78 #define STIH4XX_ETH_SEL_TX_RETIME_CLK		BIT(8)
79 #define STIH4XX_ETH_SEL_INTERNAL_NOTEXT_PHYCLK	BIT(7)
80 #define STIH4XX_ETH_SEL_TXCLK_NOT_CLK125	BIT(6)
81 
82 /* STiD127 register definitions
83  *-----------------------
84  * src	 |BIT(6)| BIT(7)|
85  *-----------------------
86  * MII   |  1	|   n/a	|
87  *-----------------------
88  * RMII  |  n/a	|   1	|
89  * clkgen|	|	|
90  *-----------------------
91  * RMII  |  n/a	|   0	|
92  * phyclk|	|	|
93  *-----------------------
94  * RGMII |  1	|  n/a	|
95  * clkgen|	|	|
96  *-----------------------
97  */
98 
99 #define STID127_RETIME_SRC_MASK			GENMASK(7, 6)
100 #define STID127_ETH_SEL_INTERNAL_NOTEXT_PHYCLK	BIT(7)
101 #define STID127_ETH_SEL_INTERNAL_NOTEXT_TXCLK	BIT(6)
102 
103 #define ENMII_MASK	GENMASK(5, 5)
104 #define ENMII		BIT(5)
105 #define EN_MASK		GENMASK(1, 1)
106 #define EN		BIT(1)
107 
108 /*
109  * 3 bits [4:2]
110  *	000-GMII/MII
111  *	001-RGMII
112  *	010-SGMII
113  *	100-RMII
114  */
115 #define MII_PHY_SEL_MASK	GENMASK(4, 2)
116 #define ETH_PHY_SEL_RMII	BIT(4)
117 #define ETH_PHY_SEL_SGMII	BIT(3)
118 #define ETH_PHY_SEL_RGMII	BIT(2)
119 #define ETH_PHY_SEL_GMII	0x0
120 #define ETH_PHY_SEL_MII		0x0
121 
122 struct sti_dwmac {
123 	int interface;		/* MII interface */
124 	bool ext_phyclk;	/* Clock from external PHY */
125 	u32 tx_retime_src;	/* TXCLK Retiming*/
126 	struct clk *clk;	/* PHY clock */
127 	u32 ctrl_reg;		/* GMAC glue-logic control register */
128 	int clk_sel_reg;	/* GMAC ext clk selection register */
129 	struct device *dev;
130 	struct regmap *regmap;
131 	bool gmac_en;
132 	u32 speed;
133 	void (*fix_retime_src)(void *priv, unsigned int speed);
134 };
135 
136 struct sti_dwmac_of_data {
137 	void (*fix_retime_src)(void *priv, unsigned int speed);
138 };
139 
140 static u32 phy_intf_sels[] = {
141 	[PHY_INTERFACE_MODE_MII] = ETH_PHY_SEL_MII,
142 	[PHY_INTERFACE_MODE_GMII] = ETH_PHY_SEL_GMII,
143 	[PHY_INTERFACE_MODE_RGMII] = ETH_PHY_SEL_RGMII,
144 	[PHY_INTERFACE_MODE_RGMII_ID] = ETH_PHY_SEL_RGMII,
145 	[PHY_INTERFACE_MODE_SGMII] = ETH_PHY_SEL_SGMII,
146 	[PHY_INTERFACE_MODE_RMII] = ETH_PHY_SEL_RMII,
147 };
148 
149 enum {
150 	TX_RETIME_SRC_NA = 0,
151 	TX_RETIME_SRC_TXCLK = 1,
152 	TX_RETIME_SRC_CLK_125,
153 	TX_RETIME_SRC_PHYCLK,
154 	TX_RETIME_SRC_CLKGEN,
155 };
156 
157 static u32 stih4xx_tx_retime_val[] = {
158 	[TX_RETIME_SRC_TXCLK] = STIH4XX_ETH_SEL_TXCLK_NOT_CLK125,
159 	[TX_RETIME_SRC_CLK_125] = 0x0,
160 	[TX_RETIME_SRC_PHYCLK] = STIH4XX_ETH_SEL_TX_RETIME_CLK,
161 	[TX_RETIME_SRC_CLKGEN] = STIH4XX_ETH_SEL_TX_RETIME_CLK
162 				 | STIH4XX_ETH_SEL_INTERNAL_NOTEXT_PHYCLK,
163 };
164 
165 static void stih4xx_fix_retime_src(void *priv, u32 spd)
166 {
167 	struct sti_dwmac *dwmac = priv;
168 	u32 src = dwmac->tx_retime_src;
169 	u32 reg = dwmac->ctrl_reg;
170 	u32 freq = 0;
171 
172 	if (dwmac->interface == PHY_INTERFACE_MODE_MII) {
173 		src = TX_RETIME_SRC_TXCLK;
174 	} else if (dwmac->interface == PHY_INTERFACE_MODE_RMII) {
175 		if (dwmac->ext_phyclk) {
176 			src = TX_RETIME_SRC_PHYCLK;
177 		} else {
178 			src = TX_RETIME_SRC_CLKGEN;
179 			freq = DWMAC_50MHZ;
180 		}
181 	} else if (IS_PHY_IF_MODE_RGMII(dwmac->interface)) {
182 		/* On GiGa clk source can be either ext or from clkgen */
183 		if (spd == SPEED_1000) {
184 			freq = DWMAC_125MHZ;
185 		} else {
186 			/* Switch to clkgen for these speeds */
187 			src = TX_RETIME_SRC_CLKGEN;
188 			if (spd == SPEED_100)
189 				freq = DWMAC_25MHZ;
190 			else if (spd == SPEED_10)
191 				freq = DWMAC_2_5MHZ;
192 		}
193 	}
194 
195 	if (src == TX_RETIME_SRC_CLKGEN && freq)
196 		clk_set_rate(dwmac->clk, freq);
197 
198 	regmap_update_bits(dwmac->regmap, reg, STIH4XX_RETIME_SRC_MASK,
199 			   stih4xx_tx_retime_val[src]);
200 }
201 
202 static void stid127_fix_retime_src(void *priv, u32 spd)
203 {
204 	struct sti_dwmac *dwmac = priv;
205 	u32 reg = dwmac->ctrl_reg;
206 	u32 freq = 0;
207 	u32 val = 0;
208 
209 	if (dwmac->interface == PHY_INTERFACE_MODE_MII) {
210 		val = STID127_ETH_SEL_INTERNAL_NOTEXT_TXCLK;
211 	} else if (dwmac->interface == PHY_INTERFACE_MODE_RMII) {
212 		if (!dwmac->ext_phyclk) {
213 			val = STID127_ETH_SEL_INTERNAL_NOTEXT_PHYCLK;
214 			freq = DWMAC_50MHZ;
215 		}
216 	} else if (IS_PHY_IF_MODE_RGMII(dwmac->interface)) {
217 		val = STID127_ETH_SEL_INTERNAL_NOTEXT_TXCLK;
218 		if (spd == SPEED_1000)
219 			freq = DWMAC_125MHZ;
220 		else if (spd == SPEED_100)
221 			freq = DWMAC_25MHZ;
222 		else if (spd == SPEED_10)
223 			freq = DWMAC_2_5MHZ;
224 	}
225 
226 	if (freq)
227 		clk_set_rate(dwmac->clk, freq);
228 
229 	regmap_update_bits(dwmac->regmap, reg, STID127_RETIME_SRC_MASK, val);
230 }
231 
232 static int sti_dwmac_set_mode(struct sti_dwmac *dwmac)
233 {
234 	struct regmap *regmap = dwmac->regmap;
235 	int iface = dwmac->interface;
236 	u32 reg = dwmac->ctrl_reg;
237 	u32 val;
238 
239 	if (dwmac->gmac_en)
240 		regmap_update_bits(regmap, reg, EN_MASK, EN);
241 
242 	regmap_update_bits(regmap, reg, MII_PHY_SEL_MASK, phy_intf_sels[iface]);
243 
244 	val = (iface == PHY_INTERFACE_MODE_REVMII) ? 0 : ENMII;
245 	regmap_update_bits(regmap, reg, ENMII_MASK, val);
246 
247 	dwmac->fix_retime_src(dwmac, dwmac->speed);
248 
249 	return 0;
250 }
251 
252 static int sti_dwmac_parse_data(struct sti_dwmac *dwmac,
253 				struct platform_device *pdev)
254 {
255 	struct resource *res;
256 	struct device *dev = &pdev->dev;
257 	struct device_node *np = dev->of_node;
258 	struct regmap *regmap;
259 	int err;
260 
261 	/* clk selection from extra syscfg register */
262 	dwmac->clk_sel_reg = -ENXIO;
263 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sti-clkconf");
264 	if (res)
265 		dwmac->clk_sel_reg = res->start;
266 
267 	regmap = syscon_regmap_lookup_by_phandle(np, "st,syscon");
268 	if (IS_ERR(regmap))
269 		return PTR_ERR(regmap);
270 
271 	err = of_property_read_u32_index(np, "st,syscon", 1, &dwmac->ctrl_reg);
272 	if (err) {
273 		dev_err(dev, "Can't get sysconfig ctrl offset (%d)\n", err);
274 		return err;
275 	}
276 
277 	dwmac->dev = dev;
278 	dwmac->interface = of_get_phy_mode(np);
279 	dwmac->regmap = regmap;
280 	dwmac->gmac_en = of_property_read_bool(np, "st,gmac_en");
281 	dwmac->ext_phyclk = of_property_read_bool(np, "st,ext-phyclk");
282 	dwmac->tx_retime_src = TX_RETIME_SRC_NA;
283 	dwmac->speed = SPEED_100;
284 
285 	if (IS_PHY_IF_MODE_GBIT(dwmac->interface)) {
286 		const char *rs;
287 
288 		dwmac->tx_retime_src = TX_RETIME_SRC_CLKGEN;
289 
290 		err = of_property_read_string(np, "st,tx-retime-src", &rs);
291 		if (err < 0) {
292 			dev_warn(dev, "Use internal clock source\n");
293 		} else {
294 			if (!strcasecmp(rs, "clk_125"))
295 				dwmac->tx_retime_src = TX_RETIME_SRC_CLK_125;
296 			else if (!strcasecmp(rs, "txclk"))
297 				dwmac->tx_retime_src = TX_RETIME_SRC_TXCLK;
298 		}
299 		dwmac->speed = SPEED_1000;
300 	}
301 
302 	dwmac->clk = devm_clk_get(dev, "sti-ethclk");
303 	if (IS_ERR(dwmac->clk)) {
304 		dev_warn(dev, "No phy clock provided...\n");
305 		dwmac->clk = NULL;
306 	}
307 
308 	return 0;
309 }
310 
311 static int sti_dwmac_probe(struct platform_device *pdev)
312 {
313 	struct plat_stmmacenet_data *plat_dat;
314 	const struct sti_dwmac_of_data *data;
315 	struct stmmac_resources stmmac_res;
316 	struct sti_dwmac *dwmac;
317 	int ret;
318 
319 	data = of_device_get_match_data(&pdev->dev);
320 	if (!data) {
321 		dev_err(&pdev->dev, "No OF match data provided\n");
322 		return -EINVAL;
323 	}
324 
325 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
326 	if (ret)
327 		return ret;
328 
329 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
330 	if (IS_ERR(plat_dat))
331 		return PTR_ERR(plat_dat);
332 
333 	dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
334 	if (!dwmac)
335 		return -ENOMEM;
336 
337 	ret = sti_dwmac_parse_data(dwmac, pdev);
338 	if (ret) {
339 		dev_err(&pdev->dev, "Unable to parse OF data\n");
340 		return ret;
341 	}
342 
343 	dwmac->fix_retime_src = data->fix_retime_src;
344 
345 	plat_dat->bsp_priv = dwmac;
346 	plat_dat->fix_mac_speed = data->fix_retime_src;
347 
348 	ret = clk_prepare_enable(dwmac->clk);
349 	if (ret)
350 		return ret;
351 
352 	ret = sti_dwmac_set_mode(dwmac);
353 	if (ret)
354 		goto disable_clk;
355 
356 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
357 	if (ret)
358 		goto disable_clk;
359 
360 	return 0;
361 
362 disable_clk:
363 	clk_disable_unprepare(dwmac->clk);
364 	return ret;
365 }
366 
367 static int sti_dwmac_remove(struct platform_device *pdev)
368 {
369 	struct sti_dwmac *dwmac = get_stmmac_bsp_priv(&pdev->dev);
370 	int ret = stmmac_dvr_remove(&pdev->dev);
371 
372 	clk_disable_unprepare(dwmac->clk);
373 
374 	return ret;
375 }
376 
377 #ifdef CONFIG_PM_SLEEP
378 static int sti_dwmac_suspend(struct device *dev)
379 {
380 	struct sti_dwmac *dwmac = get_stmmac_bsp_priv(dev);
381 	int ret = stmmac_suspend(dev);
382 
383 	clk_disable_unprepare(dwmac->clk);
384 
385 	return ret;
386 }
387 
388 static int sti_dwmac_resume(struct device *dev)
389 {
390 	struct sti_dwmac *dwmac = get_stmmac_bsp_priv(dev);
391 
392 	clk_prepare_enable(dwmac->clk);
393 	sti_dwmac_set_mode(dwmac);
394 
395 	return stmmac_resume(dev);
396 }
397 #endif /* CONFIG_PM_SLEEP */
398 
399 static SIMPLE_DEV_PM_OPS(sti_dwmac_pm_ops, sti_dwmac_suspend,
400 					   sti_dwmac_resume);
401 
402 static const struct sti_dwmac_of_data stih4xx_dwmac_data = {
403 	.fix_retime_src = stih4xx_fix_retime_src,
404 };
405 
406 static const struct sti_dwmac_of_data stid127_dwmac_data = {
407 	.fix_retime_src = stid127_fix_retime_src,
408 };
409 
410 static const struct of_device_id sti_dwmac_match[] = {
411 	{ .compatible = "st,stih415-dwmac", .data = &stih4xx_dwmac_data},
412 	{ .compatible = "st,stih416-dwmac", .data = &stih4xx_dwmac_data},
413 	{ .compatible = "st,stid127-dwmac", .data = &stid127_dwmac_data},
414 	{ .compatible = "st,stih407-dwmac", .data = &stih4xx_dwmac_data},
415 	{ }
416 };
417 MODULE_DEVICE_TABLE(of, sti_dwmac_match);
418 
419 static struct platform_driver sti_dwmac_driver = {
420 	.probe  = sti_dwmac_probe,
421 	.remove = sti_dwmac_remove,
422 	.driver = {
423 		.name           = "sti-dwmac",
424 		.pm		= &sti_dwmac_pm_ops,
425 		.of_match_table = sti_dwmac_match,
426 	},
427 };
428 module_platform_driver(sti_dwmac_driver);
429 
430 MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@st.com>");
431 MODULE_DESCRIPTION("STMicroelectronics DWMAC Specific Glue layer");
432 MODULE_LICENSE("GPL");
433