1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * dwmac-stm32.c - DWMAC Specific Glue layer for STM32 MCU
4  *
5  * Copyright (C) STMicroelectronics SA 2017
6  * Author:  Alexandre Torgue <alexandre.torgue@st.com> for STMicroelectronics.
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/kernel.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_device.h>
15 #include <linux/of_net.h>
16 #include <linux/phy.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_wakeirq.h>
19 #include <linux/regmap.h>
20 #include <linux/slab.h>
21 #include <linux/stmmac.h>
22 
23 #include "stmmac_platform.h"
24 
25 #define SYSCFG_MCU_ETH_MASK		BIT(23)
26 #define SYSCFG_MP1_ETH_MASK		GENMASK(23, 16)
27 #define SYSCFG_PMCCLRR_OFFSET		0x40
28 
29 #define SYSCFG_PMCR_ETH_CLK_SEL		BIT(16)
30 #define SYSCFG_PMCR_ETH_REF_CLK_SEL	BIT(17)
31 
32 /*  Ethernet PHY interface selection in register SYSCFG Configuration
33  *------------------------------------------
34  * src	 |BIT(23)| BIT(22)| BIT(21)|BIT(20)|
35  *------------------------------------------
36  * MII   |   0	 |   0	  |   0    |   1   |
37  *------------------------------------------
38  * GMII  |   0	 |   0	  |   0    |   0   |
39  *------------------------------------------
40  * RGMII |   0	 |   0	  |   1	   |  n/a  |
41  *------------------------------------------
42  * RMII  |   1	 |   0	  |   0	   |  n/a  |
43  *------------------------------------------
44  */
45 #define SYSCFG_PMCR_ETH_SEL_MII		BIT(20)
46 #define SYSCFG_PMCR_ETH_SEL_RGMII	BIT(21)
47 #define SYSCFG_PMCR_ETH_SEL_RMII	BIT(23)
48 #define SYSCFG_PMCR_ETH_SEL_GMII	0
49 #define SYSCFG_MCU_ETH_SEL_MII		0
50 #define SYSCFG_MCU_ETH_SEL_RMII		1
51 
52 /* STM32MP1 register definitions
53  *
54  * Below table summarizes the clock requirement and clock sources for
55  * supported phy interface modes.
56  * __________________________________________________________________________
57  *|PHY_MODE | Normal | PHY wo crystal|   PHY wo crystal   |No 125Mhz from PHY|
58  *|         |        |      25MHz    |        50MHz       |                  |
59  * ---------------------------------------------------------------------------
60  *|  MII    |	 -   |     eth-ck    |	      n/a	  |	  n/a        |
61  *|         |        |		     |                    |		     |
62  * ---------------------------------------------------------------------------
63  *|  GMII   |	 -   |     eth-ck    |	      n/a	  |	  n/a        |
64  *|         |        |               |                    |		     |
65  * ---------------------------------------------------------------------------
66  *| RGMII   |	 -   |     eth-ck    |	      n/a	  |  eth-ck (no pin) |
67  *|         |        |               |                    |  st,eth-clk-sel  |
68  * ---------------------------------------------------------------------------
69  *| RMII    |	 -   |     eth-ck    |	    eth-ck        |	  n/a        |
70  *|         |        |		     | st,eth-ref-clk-sel |		     |
71  * ---------------------------------------------------------------------------
72  *
73  * BIT(17) : set this bit in RMII mode when you have PHY without crystal 50MHz
74  * BIT(16) : set this bit in GMII/RGMII PHY when you do not want use 125Mhz
75  * from PHY
76  *-----------------------------------------------------
77  * src	 |         BIT(17)       |       BIT(16)      |
78  *-----------------------------------------------------
79  * MII   |           n/a	 |         n/a        |
80  *-----------------------------------------------------
81  * GMII  |           n/a         |   st,eth-clk-sel   |
82  *-----------------------------------------------------
83  * RGMII |           n/a         |   st,eth-clk-sel   |
84  *-----------------------------------------------------
85  * RMII  |   st,eth-ref-clk-sel	 |         n/a        |
86  *-----------------------------------------------------
87  *
88  */
89 
90 struct stm32_dwmac {
91 	struct clk *clk_tx;
92 	struct clk *clk_rx;
93 	struct clk *clk_eth_ck;
94 	struct clk *clk_ethstp;
95 	struct clk *syscfg_clk;
96 	int eth_clk_sel_reg;
97 	int eth_ref_clk_sel_reg;
98 	int irq_pwr_wakeup;
99 	u32 mode_reg;		 /* MAC glue-logic mode register */
100 	struct regmap *regmap;
101 	u32 speed;
102 	const struct stm32_ops *ops;
103 	struct device *dev;
104 };
105 
106 struct stm32_ops {
107 	int (*set_mode)(struct plat_stmmacenet_data *plat_dat);
108 	int (*clk_prepare)(struct stm32_dwmac *dwmac, bool prepare);
109 	int (*suspend)(struct stm32_dwmac *dwmac);
110 	void (*resume)(struct stm32_dwmac *dwmac);
111 	int (*parse_data)(struct stm32_dwmac *dwmac,
112 			  struct device *dev);
113 	u32 syscfg_eth_mask;
114 };
115 
116 static int stm32_dwmac_init(struct plat_stmmacenet_data *plat_dat)
117 {
118 	struct stm32_dwmac *dwmac = plat_dat->bsp_priv;
119 	int ret;
120 
121 	if (dwmac->ops->set_mode) {
122 		ret = dwmac->ops->set_mode(plat_dat);
123 		if (ret)
124 			return ret;
125 	}
126 
127 	ret = clk_prepare_enable(dwmac->clk_tx);
128 	if (ret)
129 		return ret;
130 
131 	if (!dwmac->dev->power.is_suspended) {
132 		ret = clk_prepare_enable(dwmac->clk_rx);
133 		if (ret) {
134 			clk_disable_unprepare(dwmac->clk_tx);
135 			return ret;
136 		}
137 	}
138 
139 	if (dwmac->ops->clk_prepare) {
140 		ret = dwmac->ops->clk_prepare(dwmac, true);
141 		if (ret) {
142 			clk_disable_unprepare(dwmac->clk_rx);
143 			clk_disable_unprepare(dwmac->clk_tx);
144 		}
145 	}
146 
147 	return ret;
148 }
149 
150 static int stm32mp1_clk_prepare(struct stm32_dwmac *dwmac, bool prepare)
151 {
152 	int ret = 0;
153 
154 	if (prepare) {
155 		ret = clk_prepare_enable(dwmac->syscfg_clk);
156 		if (ret)
157 			return ret;
158 		ret = clk_prepare_enable(dwmac->clk_eth_ck);
159 		if (ret) {
160 			clk_disable_unprepare(dwmac->syscfg_clk);
161 			return ret;
162 		}
163 	} else {
164 		clk_disable_unprepare(dwmac->syscfg_clk);
165 		clk_disable_unprepare(dwmac->clk_eth_ck);
166 	}
167 	return ret;
168 }
169 
170 static int stm32mp1_set_mode(struct plat_stmmacenet_data *plat_dat)
171 {
172 	struct stm32_dwmac *dwmac = plat_dat->bsp_priv;
173 	u32 reg = dwmac->mode_reg;
174 	int val;
175 
176 	switch (plat_dat->interface) {
177 	case PHY_INTERFACE_MODE_MII:
178 		val = SYSCFG_PMCR_ETH_SEL_MII;
179 		pr_debug("SYSCFG init : PHY_INTERFACE_MODE_MII\n");
180 		break;
181 	case PHY_INTERFACE_MODE_GMII:
182 		val = SYSCFG_PMCR_ETH_SEL_GMII;
183 		if (dwmac->eth_clk_sel_reg)
184 			val |= SYSCFG_PMCR_ETH_CLK_SEL;
185 		pr_debug("SYSCFG init : PHY_INTERFACE_MODE_GMII\n");
186 		break;
187 	case PHY_INTERFACE_MODE_RMII:
188 		val = SYSCFG_PMCR_ETH_SEL_RMII;
189 		if (dwmac->eth_ref_clk_sel_reg)
190 			val |= SYSCFG_PMCR_ETH_REF_CLK_SEL;
191 		pr_debug("SYSCFG init : PHY_INTERFACE_MODE_RMII\n");
192 		break;
193 	case PHY_INTERFACE_MODE_RGMII:
194 	case PHY_INTERFACE_MODE_RGMII_ID:
195 	case PHY_INTERFACE_MODE_RGMII_RXID:
196 	case PHY_INTERFACE_MODE_RGMII_TXID:
197 		val = SYSCFG_PMCR_ETH_SEL_RGMII;
198 		if (dwmac->eth_clk_sel_reg)
199 			val |= SYSCFG_PMCR_ETH_CLK_SEL;
200 		pr_debug("SYSCFG init : PHY_INTERFACE_MODE_RGMII\n");
201 		break;
202 	default:
203 		pr_debug("SYSCFG init :  Do not manage %d interface\n",
204 			 plat_dat->interface);
205 		/* Do not manage others interfaces */
206 		return -EINVAL;
207 	}
208 
209 	/* Need to update PMCCLRR (clear register) */
210 	regmap_write(dwmac->regmap, reg + SYSCFG_PMCCLRR_OFFSET,
211 		     dwmac->ops->syscfg_eth_mask);
212 
213 	/* Update PMCSETR (set register) */
214 	return regmap_update_bits(dwmac->regmap, reg,
215 				 dwmac->ops->syscfg_eth_mask, val);
216 }
217 
218 static int stm32mcu_set_mode(struct plat_stmmacenet_data *plat_dat)
219 {
220 	struct stm32_dwmac *dwmac = plat_dat->bsp_priv;
221 	u32 reg = dwmac->mode_reg;
222 	int val;
223 
224 	switch (plat_dat->interface) {
225 	case PHY_INTERFACE_MODE_MII:
226 		val = SYSCFG_MCU_ETH_SEL_MII;
227 		pr_debug("SYSCFG init : PHY_INTERFACE_MODE_MII\n");
228 		break;
229 	case PHY_INTERFACE_MODE_RMII:
230 		val = SYSCFG_MCU_ETH_SEL_RMII;
231 		pr_debug("SYSCFG init : PHY_INTERFACE_MODE_RMII\n");
232 		break;
233 	default:
234 		pr_debug("SYSCFG init :  Do not manage %d interface\n",
235 			 plat_dat->interface);
236 		/* Do not manage others interfaces */
237 		return -EINVAL;
238 	}
239 
240 	return regmap_update_bits(dwmac->regmap, reg,
241 				 dwmac->ops->syscfg_eth_mask, val << 23);
242 }
243 
244 static void stm32_dwmac_clk_disable(struct stm32_dwmac *dwmac)
245 {
246 	clk_disable_unprepare(dwmac->clk_tx);
247 	clk_disable_unprepare(dwmac->clk_rx);
248 
249 	if (dwmac->ops->clk_prepare)
250 		dwmac->ops->clk_prepare(dwmac, false);
251 }
252 
253 static int stm32_dwmac_parse_data(struct stm32_dwmac *dwmac,
254 				  struct device *dev)
255 {
256 	struct device_node *np = dev->of_node;
257 	int err;
258 
259 	/*  Get TX/RX clocks */
260 	dwmac->clk_tx = devm_clk_get(dev, "mac-clk-tx");
261 	if (IS_ERR(dwmac->clk_tx)) {
262 		dev_err(dev, "No ETH Tx clock provided...\n");
263 		return PTR_ERR(dwmac->clk_tx);
264 	}
265 
266 	dwmac->clk_rx = devm_clk_get(dev, "mac-clk-rx");
267 	if (IS_ERR(dwmac->clk_rx)) {
268 		dev_err(dev, "No ETH Rx clock provided...\n");
269 		return PTR_ERR(dwmac->clk_rx);
270 	}
271 
272 	if (dwmac->ops->parse_data) {
273 		err = dwmac->ops->parse_data(dwmac, dev);
274 		if (err)
275 			return err;
276 	}
277 
278 	/* Get mode register */
279 	dwmac->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscon");
280 	if (IS_ERR(dwmac->regmap))
281 		return PTR_ERR(dwmac->regmap);
282 
283 	err = of_property_read_u32_index(np, "st,syscon", 1, &dwmac->mode_reg);
284 	if (err)
285 		dev_err(dev, "Can't get sysconfig mode offset (%d)\n", err);
286 
287 	return err;
288 }
289 
290 static int stm32mp1_parse_data(struct stm32_dwmac *dwmac,
291 			       struct device *dev)
292 {
293 	struct platform_device *pdev = to_platform_device(dev);
294 	struct device_node *np = dev->of_node;
295 	int err = 0;
296 
297 	/* Gigabit Ethernet 125MHz clock selection. */
298 	dwmac->eth_clk_sel_reg = of_property_read_bool(np, "st,eth-clk-sel");
299 
300 	/* Ethernet 50Mhz RMII clock selection */
301 	dwmac->eth_ref_clk_sel_reg =
302 		of_property_read_bool(np, "st,eth-ref-clk-sel");
303 
304 	/*  Get ETH_CLK clocks */
305 	dwmac->clk_eth_ck = devm_clk_get(dev, "eth-ck");
306 	if (IS_ERR(dwmac->clk_eth_ck)) {
307 		dev_info(dev, "No phy clock provided...\n");
308 		dwmac->clk_eth_ck = NULL;
309 	}
310 
311 	/*  Clock used for low power mode */
312 	dwmac->clk_ethstp = devm_clk_get(dev, "ethstp");
313 	if (IS_ERR(dwmac->clk_ethstp)) {
314 		dev_err(dev,
315 			"No ETH peripheral clock provided for CStop mode ...\n");
316 		return PTR_ERR(dwmac->clk_ethstp);
317 	}
318 
319 	/*  Optional Clock for sysconfig */
320 	dwmac->syscfg_clk = devm_clk_get(dev, "syscfg-clk");
321 	if (IS_ERR(dwmac->syscfg_clk))
322 		dwmac->syscfg_clk = NULL;
323 
324 	/* Get IRQ information early to have an ability to ask for deferred
325 	 * probe if needed before we went too far with resource allocation.
326 	 */
327 	dwmac->irq_pwr_wakeup = platform_get_irq_byname_optional(pdev,
328 							"stm32_pwr_wakeup");
329 	if (dwmac->irq_pwr_wakeup == -EPROBE_DEFER)
330 		return -EPROBE_DEFER;
331 
332 	if (!dwmac->clk_eth_ck && dwmac->irq_pwr_wakeup >= 0) {
333 		err = device_init_wakeup(&pdev->dev, true);
334 		if (err) {
335 			dev_err(&pdev->dev, "Failed to init wake up irq\n");
336 			return err;
337 		}
338 		err = dev_pm_set_dedicated_wake_irq(&pdev->dev,
339 						    dwmac->irq_pwr_wakeup);
340 		if (err) {
341 			dev_err(&pdev->dev, "Failed to set wake up irq\n");
342 			device_init_wakeup(&pdev->dev, false);
343 		}
344 		device_set_wakeup_enable(&pdev->dev, false);
345 	}
346 	return err;
347 }
348 
349 static int stm32_dwmac_probe(struct platform_device *pdev)
350 {
351 	struct plat_stmmacenet_data *plat_dat;
352 	struct stmmac_resources stmmac_res;
353 	struct stm32_dwmac *dwmac;
354 	const struct stm32_ops *data;
355 	int ret;
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 		ret = -ENOMEM;
368 		goto err_remove_config_dt;
369 	}
370 
371 	data = of_device_get_match_data(&pdev->dev);
372 	if (!data) {
373 		dev_err(&pdev->dev, "no of match data provided\n");
374 		ret = -EINVAL;
375 		goto err_remove_config_dt;
376 	}
377 
378 	dwmac->ops = data;
379 	dwmac->dev = &pdev->dev;
380 
381 	ret = stm32_dwmac_parse_data(dwmac, &pdev->dev);
382 	if (ret) {
383 		dev_err(&pdev->dev, "Unable to parse OF data\n");
384 		goto err_remove_config_dt;
385 	}
386 
387 	plat_dat->bsp_priv = dwmac;
388 
389 	ret = stm32_dwmac_init(plat_dat);
390 	if (ret)
391 		goto err_remove_config_dt;
392 
393 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
394 	if (ret)
395 		goto err_clk_disable;
396 
397 	return 0;
398 
399 err_clk_disable:
400 	stm32_dwmac_clk_disable(dwmac);
401 err_remove_config_dt:
402 	stmmac_remove_config_dt(pdev, plat_dat);
403 
404 	return ret;
405 }
406 
407 static int stm32_dwmac_remove(struct platform_device *pdev)
408 {
409 	struct net_device *ndev = platform_get_drvdata(pdev);
410 	struct stmmac_priv *priv = netdev_priv(ndev);
411 	int ret = stmmac_dvr_remove(&pdev->dev);
412 	struct stm32_dwmac *dwmac = priv->plat->bsp_priv;
413 
414 	stm32_dwmac_clk_disable(priv->plat->bsp_priv);
415 
416 	if (dwmac->irq_pwr_wakeup >= 0) {
417 		dev_pm_clear_wake_irq(&pdev->dev);
418 		device_init_wakeup(&pdev->dev, false);
419 	}
420 
421 	return ret;
422 }
423 
424 static int stm32mp1_suspend(struct stm32_dwmac *dwmac)
425 {
426 	int ret = 0;
427 
428 	ret = clk_prepare_enable(dwmac->clk_ethstp);
429 	if (ret)
430 		return ret;
431 
432 	clk_disable_unprepare(dwmac->clk_tx);
433 	clk_disable_unprepare(dwmac->syscfg_clk);
434 	clk_disable_unprepare(dwmac->clk_eth_ck);
435 
436 	return ret;
437 }
438 
439 static void stm32mp1_resume(struct stm32_dwmac *dwmac)
440 {
441 	clk_disable_unprepare(dwmac->clk_ethstp);
442 }
443 
444 static int stm32mcu_suspend(struct stm32_dwmac *dwmac)
445 {
446 	clk_disable_unprepare(dwmac->clk_tx);
447 	clk_disable_unprepare(dwmac->clk_rx);
448 
449 	return 0;
450 }
451 
452 #ifdef CONFIG_PM_SLEEP
453 static int stm32_dwmac_suspend(struct device *dev)
454 {
455 	struct net_device *ndev = dev_get_drvdata(dev);
456 	struct stmmac_priv *priv = netdev_priv(ndev);
457 	struct stm32_dwmac *dwmac = priv->plat->bsp_priv;
458 
459 	int ret;
460 
461 	ret = stmmac_suspend(dev);
462 
463 	if (dwmac->ops->suspend)
464 		ret = dwmac->ops->suspend(dwmac);
465 
466 	return ret;
467 }
468 
469 static int stm32_dwmac_resume(struct device *dev)
470 {
471 	struct net_device *ndev = dev_get_drvdata(dev);
472 	struct stmmac_priv *priv = netdev_priv(ndev);
473 	struct stm32_dwmac *dwmac = priv->plat->bsp_priv;
474 	int ret;
475 
476 	if (dwmac->ops->resume)
477 		dwmac->ops->resume(dwmac);
478 
479 	ret = stm32_dwmac_init(priv->plat);
480 	if (ret)
481 		return ret;
482 
483 	ret = stmmac_resume(dev);
484 
485 	return ret;
486 }
487 #endif /* CONFIG_PM_SLEEP */
488 
489 static SIMPLE_DEV_PM_OPS(stm32_dwmac_pm_ops,
490 	stm32_dwmac_suspend, stm32_dwmac_resume);
491 
492 static struct stm32_ops stm32mcu_dwmac_data = {
493 	.set_mode = stm32mcu_set_mode,
494 	.suspend = stm32mcu_suspend,
495 	.syscfg_eth_mask = SYSCFG_MCU_ETH_MASK
496 };
497 
498 static struct stm32_ops stm32mp1_dwmac_data = {
499 	.set_mode = stm32mp1_set_mode,
500 	.clk_prepare = stm32mp1_clk_prepare,
501 	.suspend = stm32mp1_suspend,
502 	.resume = stm32mp1_resume,
503 	.parse_data = stm32mp1_parse_data,
504 	.syscfg_eth_mask = SYSCFG_MP1_ETH_MASK
505 };
506 
507 static const struct of_device_id stm32_dwmac_match[] = {
508 	{ .compatible = "st,stm32-dwmac", .data = &stm32mcu_dwmac_data},
509 	{ .compatible = "st,stm32mp1-dwmac", .data = &stm32mp1_dwmac_data},
510 	{ }
511 };
512 MODULE_DEVICE_TABLE(of, stm32_dwmac_match);
513 
514 static struct platform_driver stm32_dwmac_driver = {
515 	.probe  = stm32_dwmac_probe,
516 	.remove = stm32_dwmac_remove,
517 	.driver = {
518 		.name           = "stm32-dwmac",
519 		.pm		= &stm32_dwmac_pm_ops,
520 		.of_match_table = stm32_dwmac_match,
521 	},
522 };
523 module_platform_driver(stm32_dwmac_driver);
524 
525 MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue@gmail.com>");
526 MODULE_AUTHOR("Christophe Roullier <christophe.roullier@st.com>");
527 MODULE_DESCRIPTION("STMicroelectronics STM32 DWMAC Specific Glue layer");
528 MODULE_LICENSE("GPL v2");
529