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 	u32 speed;
132 };
133 
134 struct sti_dwmac_of_data {
135 	void (*fix_mac_speed)(void *priv, unsigned int speed);
136 	int (*init)(struct platform_device *pdev, void *priv);
137 };
138 
139 static u32 phy_intf_sels[] = {
140 	[PHY_INTERFACE_MODE_MII] = ETH_PHY_SEL_MII,
141 	[PHY_INTERFACE_MODE_GMII] = ETH_PHY_SEL_GMII,
142 	[PHY_INTERFACE_MODE_RGMII] = ETH_PHY_SEL_RGMII,
143 	[PHY_INTERFACE_MODE_RGMII_ID] = ETH_PHY_SEL_RGMII,
144 	[PHY_INTERFACE_MODE_SGMII] = ETH_PHY_SEL_SGMII,
145 	[PHY_INTERFACE_MODE_RMII] = ETH_PHY_SEL_RMII,
146 };
147 
148 enum {
149 	TX_RETIME_SRC_NA = 0,
150 	TX_RETIME_SRC_TXCLK = 1,
151 	TX_RETIME_SRC_CLK_125,
152 	TX_RETIME_SRC_PHYCLK,
153 	TX_RETIME_SRC_CLKGEN,
154 };
155 
156 static u32 stih4xx_tx_retime_val[] = {
157 	[TX_RETIME_SRC_TXCLK] = STIH4XX_ETH_SEL_TXCLK_NOT_CLK125,
158 	[TX_RETIME_SRC_CLK_125] = 0x0,
159 	[TX_RETIME_SRC_PHYCLK] = STIH4XX_ETH_SEL_TX_RETIME_CLK,
160 	[TX_RETIME_SRC_CLKGEN] = STIH4XX_ETH_SEL_TX_RETIME_CLK
161 				 | STIH4XX_ETH_SEL_INTERNAL_NOTEXT_PHYCLK,
162 };
163 
164 static void stih4xx_fix_retime_src(void *priv, u32 spd)
165 {
166 	struct sti_dwmac *dwmac = priv;
167 	u32 src = dwmac->tx_retime_src;
168 	u32 reg = dwmac->ctrl_reg;
169 	u32 freq = 0;
170 
171 	if (dwmac->interface == PHY_INTERFACE_MODE_MII) {
172 		src = TX_RETIME_SRC_TXCLK;
173 	} else if (dwmac->interface == PHY_INTERFACE_MODE_RMII) {
174 		if (dwmac->ext_phyclk) {
175 			src = TX_RETIME_SRC_PHYCLK;
176 		} else {
177 			src = TX_RETIME_SRC_CLKGEN;
178 			freq = DWMAC_50MHZ;
179 		}
180 	} else if (IS_PHY_IF_MODE_RGMII(dwmac->interface)) {
181 		/* On GiGa clk source can be either ext or from clkgen */
182 		if (spd == SPEED_1000) {
183 			freq = DWMAC_125MHZ;
184 		} else {
185 			/* Switch to clkgen for these speeds */
186 			src = TX_RETIME_SRC_CLKGEN;
187 			if (spd == SPEED_100)
188 				freq = DWMAC_25MHZ;
189 			else if (spd == SPEED_10)
190 				freq = DWMAC_2_5MHZ;
191 		}
192 	}
193 
194 	if (src == TX_RETIME_SRC_CLKGEN && dwmac->clk && freq)
195 		clk_set_rate(dwmac->clk, freq);
196 
197 	regmap_update_bits(dwmac->regmap, reg, STIH4XX_RETIME_SRC_MASK,
198 			   stih4xx_tx_retime_val[src]);
199 }
200 
201 static void stid127_fix_retime_src(void *priv, u32 spd)
202 {
203 	struct sti_dwmac *dwmac = priv;
204 	u32 reg = dwmac->ctrl_reg;
205 	u32 freq = 0;
206 	u32 val = 0;
207 
208 	if (dwmac->interface == PHY_INTERFACE_MODE_MII) {
209 		val = STID127_ETH_SEL_INTERNAL_NOTEXT_TXCLK;
210 	} else if (dwmac->interface == PHY_INTERFACE_MODE_RMII) {
211 		if (!dwmac->ext_phyclk) {
212 			val = STID127_ETH_SEL_INTERNAL_NOTEXT_PHYCLK;
213 			freq = DWMAC_50MHZ;
214 		}
215 	} else if (IS_PHY_IF_MODE_RGMII(dwmac->interface)) {
216 		val = STID127_ETH_SEL_INTERNAL_NOTEXT_TXCLK;
217 		if (spd == SPEED_1000)
218 			freq = DWMAC_125MHZ;
219 		else if (spd == SPEED_100)
220 			freq = DWMAC_25MHZ;
221 		else if (spd == SPEED_10)
222 			freq = DWMAC_2_5MHZ;
223 	}
224 
225 	if (dwmac->clk && freq)
226 		clk_set_rate(dwmac->clk, freq);
227 
228 	regmap_update_bits(dwmac->regmap, reg, STID127_RETIME_SRC_MASK, val);
229 }
230 
231 static void sti_dwmac_ctrl_init(struct sti_dwmac *dwmac)
232 {
233 	struct regmap *regmap = dwmac->regmap;
234 	int iface = dwmac->interface;
235 	struct device *dev = dwmac->dev;
236 	struct device_node *np = dev->of_node;
237 	u32 reg = dwmac->ctrl_reg;
238 	u32 val;
239 
240 	if (dwmac->clk)
241 		clk_prepare_enable(dwmac->clk);
242 
243 	if (of_property_read_bool(np, "st,gmac_en"))
244 		regmap_update_bits(regmap, reg, EN_MASK, EN);
245 
246 	regmap_update_bits(regmap, reg, MII_PHY_SEL_MASK, phy_intf_sels[iface]);
247 
248 	val = (iface == PHY_INTERFACE_MODE_REVMII) ? 0 : ENMII;
249 	regmap_update_bits(regmap, reg, ENMII_MASK, val);
250 }
251 
252 static int stix4xx_init(struct platform_device *pdev, void *priv)
253 {
254 	struct sti_dwmac *dwmac = priv;
255 	u32 spd = dwmac->speed;
256 
257 	sti_dwmac_ctrl_init(dwmac);
258 
259 	stih4xx_fix_retime_src(priv, spd);
260 
261 	return 0;
262 }
263 
264 static int stid127_init(struct platform_device *pdev, void *priv)
265 {
266 	struct sti_dwmac *dwmac = priv;
267 	u32 spd = dwmac->speed;
268 
269 	sti_dwmac_ctrl_init(dwmac);
270 
271 	stid127_fix_retime_src(priv, spd);
272 
273 	return 0;
274 }
275 
276 static void sti_dwmac_exit(struct platform_device *pdev, void *priv)
277 {
278 	struct sti_dwmac *dwmac = priv;
279 
280 	if (dwmac->clk)
281 		clk_disable_unprepare(dwmac->clk);
282 }
283 static int sti_dwmac_parse_data(struct sti_dwmac *dwmac,
284 				struct platform_device *pdev)
285 {
286 	struct resource *res;
287 	struct device *dev = &pdev->dev;
288 	struct device_node *np = dev->of_node;
289 	struct regmap *regmap;
290 	int err;
291 
292 	if (!np)
293 		return -EINVAL;
294 
295 	/* clk selection from extra syscfg register */
296 	dwmac->clk_sel_reg = -ENXIO;
297 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sti-clkconf");
298 	if (res)
299 		dwmac->clk_sel_reg = res->start;
300 
301 	regmap = syscon_regmap_lookup_by_phandle(np, "st,syscon");
302 	if (IS_ERR(regmap))
303 		return PTR_ERR(regmap);
304 
305 	err = of_property_read_u32_index(np, "st,syscon", 1, &dwmac->ctrl_reg);
306 	if (err) {
307 		dev_err(dev, "Can't get sysconfig ctrl offset (%d)\n", err);
308 		return err;
309 	}
310 
311 	dwmac->dev = dev;
312 	dwmac->interface = of_get_phy_mode(np);
313 	dwmac->regmap = regmap;
314 	dwmac->ext_phyclk = of_property_read_bool(np, "st,ext-phyclk");
315 	dwmac->tx_retime_src = TX_RETIME_SRC_NA;
316 	dwmac->speed = SPEED_100;
317 
318 	if (IS_PHY_IF_MODE_GBIT(dwmac->interface)) {
319 		const char *rs;
320 
321 		err = of_property_read_string(np, "st,tx-retime-src", &rs);
322 		if (err < 0) {
323 			dev_warn(dev, "Use internal clock source\n");
324 			dwmac->tx_retime_src = TX_RETIME_SRC_CLKGEN;
325 		} else if (!strcasecmp(rs, "clk_125")) {
326 			dwmac->tx_retime_src = TX_RETIME_SRC_CLK_125;
327 		} else if (!strcasecmp(rs, "txclk")) {
328 			dwmac->tx_retime_src = TX_RETIME_SRC_TXCLK;
329 		}
330 
331 		dwmac->speed = SPEED_1000;
332 	}
333 
334 	dwmac->clk = devm_clk_get(dev, "sti-ethclk");
335 	if (IS_ERR(dwmac->clk)) {
336 		dev_warn(dev, "No phy clock provided...\n");
337 		dwmac->clk = NULL;
338 	}
339 
340 	return 0;
341 }
342 
343 static int sti_dwmac_probe(struct platform_device *pdev)
344 {
345 	struct plat_stmmacenet_data *plat_dat;
346 	const struct sti_dwmac_of_data *data;
347 	struct stmmac_resources stmmac_res;
348 	struct sti_dwmac *dwmac;
349 	int ret;
350 
351 	data = of_device_get_match_data(&pdev->dev);
352 	if (!data) {
353 		dev_err(&pdev->dev, "No OF match data provided\n");
354 		return -EINVAL;
355 	}
356 
357 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
358 	if (ret)
359 		return ret;
360 
361 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
362 	if (IS_ERR(plat_dat))
363 		return PTR_ERR(plat_dat);
364 
365 	dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
366 	if (!dwmac)
367 		return -ENOMEM;
368 
369 	ret = sti_dwmac_parse_data(dwmac, pdev);
370 	if (ret) {
371 		dev_err(&pdev->dev, "Unable to parse OF data\n");
372 		return ret;
373 	}
374 
375 	plat_dat->bsp_priv = dwmac;
376 	plat_dat->init = data->init;
377 	plat_dat->exit = sti_dwmac_exit;
378 	plat_dat->fix_mac_speed = data->fix_mac_speed;
379 
380 	ret = plat_dat->init(pdev, plat_dat->bsp_priv);
381 	if (ret)
382 		return ret;
383 
384 	return stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
385 }
386 
387 static const struct sti_dwmac_of_data stih4xx_dwmac_data = {
388 	.fix_mac_speed = stih4xx_fix_retime_src,
389 	.init = stix4xx_init,
390 };
391 
392 static const struct sti_dwmac_of_data stid127_dwmac_data = {
393 	.fix_mac_speed = stid127_fix_retime_src,
394 	.init = stid127_init,
395 };
396 
397 static const struct of_device_id sti_dwmac_match[] = {
398 	{ .compatible = "st,stih415-dwmac", .data = &stih4xx_dwmac_data},
399 	{ .compatible = "st,stih416-dwmac", .data = &stih4xx_dwmac_data},
400 	{ .compatible = "st,stid127-dwmac", .data = &stid127_dwmac_data},
401 	{ .compatible = "st,stih407-dwmac", .data = &stih4xx_dwmac_data},
402 	{ }
403 };
404 MODULE_DEVICE_TABLE(of, sti_dwmac_match);
405 
406 static struct platform_driver sti_dwmac_driver = {
407 	.probe  = sti_dwmac_probe,
408 	.remove = stmmac_pltfr_remove,
409 	.driver = {
410 		.name           = "sti-dwmac",
411 		.pm		= &stmmac_pltfr_pm_ops,
412 		.of_match_table = sti_dwmac_match,
413 	},
414 };
415 module_platform_driver(sti_dwmac_driver);
416 
417 MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@st.com>");
418 MODULE_DESCRIPTION("STMicroelectronics DWMAC Specific Glue layer");
419 MODULE_LICENSE("GPL");
420