1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Amlogic Meson8b, Meson8m2 and GXBB DWMAC glue layer
4  *
5  * Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/clk-provider.h>
10 #include <linux/device.h>
11 #include <linux/ethtool.h>
12 #include <linux/io.h>
13 #include <linux/ioport.h>
14 #include <linux/module.h>
15 #include <linux/of_device.h>
16 #include <linux/of_net.h>
17 #include <linux/mfd/syscon.h>
18 #include <linux/platform_device.h>
19 #include <linux/stmmac.h>
20 
21 #include "stmmac_platform.h"
22 
23 #define PRG_ETH0			0x0
24 
25 #define PRG_ETH0_RGMII_MODE		BIT(0)
26 
27 #define PRG_ETH0_EXT_PHY_MODE_MASK	GENMASK(2, 0)
28 #define PRG_ETH0_EXT_RGMII_MODE		1
29 #define PRG_ETH0_EXT_RMII_MODE		4
30 
31 /* mux to choose between fclk_div2 (bit unset) and mpll2 (bit set) */
32 #define PRG_ETH0_CLK_M250_SEL_SHIFT	4
33 #define PRG_ETH0_CLK_M250_SEL_MASK	GENMASK(4, 4)
34 
35 #define PRG_ETH0_TXDLY_SHIFT		5
36 #define PRG_ETH0_TXDLY_MASK		GENMASK(6, 5)
37 
38 /* divider for the result of m250_sel */
39 #define PRG_ETH0_CLK_M250_DIV_SHIFT	7
40 #define PRG_ETH0_CLK_M250_DIV_WIDTH	3
41 
42 #define PRG_ETH0_RGMII_TX_CLK_EN	10
43 
44 #define PRG_ETH0_INVERTED_RMII_CLK	BIT(11)
45 #define PRG_ETH0_TX_AND_PHY_REF_CLK	BIT(12)
46 
47 #define MUX_CLK_NUM_PARENTS		2
48 
49 struct meson8b_dwmac;
50 
51 struct meson8b_dwmac_data {
52 	int (*set_phy_mode)(struct meson8b_dwmac *dwmac);
53 };
54 
55 struct meson8b_dwmac {
56 	struct device			*dev;
57 	void __iomem			*regs;
58 
59 	const struct meson8b_dwmac_data	*data;
60 	phy_interface_t			phy_mode;
61 	struct clk			*rgmii_tx_clk;
62 	u32				tx_delay_ns;
63 };
64 
65 struct meson8b_dwmac_clk_configs {
66 	struct clk_mux		m250_mux;
67 	struct clk_divider	m250_div;
68 	struct clk_fixed_factor	fixed_div2;
69 	struct clk_gate		rgmii_tx_en;
70 };
71 
72 static void meson8b_dwmac_mask_bits(struct meson8b_dwmac *dwmac, u32 reg,
73 				    u32 mask, u32 value)
74 {
75 	u32 data;
76 
77 	data = readl(dwmac->regs + reg);
78 	data &= ~mask;
79 	data |= (value & mask);
80 
81 	writel(data, dwmac->regs + reg);
82 }
83 
84 static struct clk *meson8b_dwmac_register_clk(struct meson8b_dwmac *dwmac,
85 					      const char *name_suffix,
86 					      const char **parent_names,
87 					      int num_parents,
88 					      const struct clk_ops *ops,
89 					      struct clk_hw *hw)
90 {
91 	struct clk_init_data init;
92 	char clk_name[32];
93 
94 	snprintf(clk_name, sizeof(clk_name), "%s#%s", dev_name(dwmac->dev),
95 		 name_suffix);
96 
97 	init.name = clk_name;
98 	init.ops = ops;
99 	init.flags = CLK_SET_RATE_PARENT;
100 	init.parent_names = parent_names;
101 	init.num_parents = num_parents;
102 
103 	hw->init = &init;
104 
105 	return devm_clk_register(dwmac->dev, hw);
106 }
107 
108 static int meson8b_init_rgmii_tx_clk(struct meson8b_dwmac *dwmac)
109 {
110 	int i, ret;
111 	struct clk *clk;
112 	struct device *dev = dwmac->dev;
113 	const char *parent_name, *mux_parent_names[MUX_CLK_NUM_PARENTS];
114 	struct meson8b_dwmac_clk_configs *clk_configs;
115 
116 	clk_configs = devm_kzalloc(dev, sizeof(*clk_configs), GFP_KERNEL);
117 	if (!clk_configs)
118 		return -ENOMEM;
119 
120 	/* get the mux parents from DT */
121 	for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
122 		char name[16];
123 
124 		snprintf(name, sizeof(name), "clkin%d", i);
125 		clk = devm_clk_get(dev, name);
126 		if (IS_ERR(clk)) {
127 			ret = PTR_ERR(clk);
128 			if (ret != -EPROBE_DEFER)
129 				dev_err(dev, "Missing clock %s\n", name);
130 			return ret;
131 		}
132 
133 		mux_parent_names[i] = __clk_get_name(clk);
134 	}
135 
136 	clk_configs->m250_mux.reg = dwmac->regs + PRG_ETH0;
137 	clk_configs->m250_mux.shift = PRG_ETH0_CLK_M250_SEL_SHIFT;
138 	clk_configs->m250_mux.mask = PRG_ETH0_CLK_M250_SEL_MASK;
139 	clk = meson8b_dwmac_register_clk(dwmac, "m250_sel", mux_parent_names,
140 					 MUX_CLK_NUM_PARENTS, &clk_mux_ops,
141 					 &clk_configs->m250_mux.hw);
142 	if (WARN_ON(IS_ERR(clk)))
143 		return PTR_ERR(clk);
144 
145 	parent_name = __clk_get_name(clk);
146 	clk_configs->m250_div.reg = dwmac->regs + PRG_ETH0;
147 	clk_configs->m250_div.shift = PRG_ETH0_CLK_M250_DIV_SHIFT;
148 	clk_configs->m250_div.width = PRG_ETH0_CLK_M250_DIV_WIDTH;
149 	clk_configs->m250_div.flags = CLK_DIVIDER_ONE_BASED |
150 				CLK_DIVIDER_ALLOW_ZERO |
151 				CLK_DIVIDER_ROUND_CLOSEST;
152 	clk = meson8b_dwmac_register_clk(dwmac, "m250_div", &parent_name, 1,
153 					 &clk_divider_ops,
154 					 &clk_configs->m250_div.hw);
155 	if (WARN_ON(IS_ERR(clk)))
156 		return PTR_ERR(clk);
157 
158 	parent_name = __clk_get_name(clk);
159 	clk_configs->fixed_div2.mult = 1;
160 	clk_configs->fixed_div2.div = 2;
161 	clk = meson8b_dwmac_register_clk(dwmac, "fixed_div2", &parent_name, 1,
162 					 &clk_fixed_factor_ops,
163 					 &clk_configs->fixed_div2.hw);
164 	if (WARN_ON(IS_ERR(clk)))
165 		return PTR_ERR(clk);
166 
167 	parent_name = __clk_get_name(clk);
168 	clk_configs->rgmii_tx_en.reg = dwmac->regs + PRG_ETH0;
169 	clk_configs->rgmii_tx_en.bit_idx = PRG_ETH0_RGMII_TX_CLK_EN;
170 	clk = meson8b_dwmac_register_clk(dwmac, "rgmii_tx_en", &parent_name, 1,
171 					 &clk_gate_ops,
172 					 &clk_configs->rgmii_tx_en.hw);
173 	if (WARN_ON(IS_ERR(clk)))
174 		return PTR_ERR(clk);
175 
176 	dwmac->rgmii_tx_clk = clk;
177 
178 	return 0;
179 }
180 
181 static int meson8b_set_phy_mode(struct meson8b_dwmac *dwmac)
182 {
183 	switch (dwmac->phy_mode) {
184 	case PHY_INTERFACE_MODE_RGMII:
185 	case PHY_INTERFACE_MODE_RGMII_RXID:
186 	case PHY_INTERFACE_MODE_RGMII_ID:
187 	case PHY_INTERFACE_MODE_RGMII_TXID:
188 		/* enable RGMII mode */
189 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
190 					PRG_ETH0_RGMII_MODE,
191 					PRG_ETH0_RGMII_MODE);
192 		break;
193 	case PHY_INTERFACE_MODE_RMII:
194 		/* disable RGMII mode -> enables RMII mode */
195 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
196 					PRG_ETH0_RGMII_MODE, 0);
197 		break;
198 	default:
199 		dev_err(dwmac->dev, "fail to set phy-mode %s\n",
200 			phy_modes(dwmac->phy_mode));
201 		return -EINVAL;
202 	}
203 
204 	return 0;
205 }
206 
207 static int meson_axg_set_phy_mode(struct meson8b_dwmac *dwmac)
208 {
209 	switch (dwmac->phy_mode) {
210 	case PHY_INTERFACE_MODE_RGMII:
211 	case PHY_INTERFACE_MODE_RGMII_RXID:
212 	case PHY_INTERFACE_MODE_RGMII_ID:
213 	case PHY_INTERFACE_MODE_RGMII_TXID:
214 		/* enable RGMII mode */
215 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
216 					PRG_ETH0_EXT_PHY_MODE_MASK,
217 					PRG_ETH0_EXT_RGMII_MODE);
218 		break;
219 	case PHY_INTERFACE_MODE_RMII:
220 		/* disable RGMII mode -> enables RMII mode */
221 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
222 					PRG_ETH0_EXT_PHY_MODE_MASK,
223 					PRG_ETH0_EXT_RMII_MODE);
224 		break;
225 	default:
226 		dev_err(dwmac->dev, "fail to set phy-mode %s\n",
227 			phy_modes(dwmac->phy_mode));
228 		return -EINVAL;
229 	}
230 
231 	return 0;
232 }
233 
234 static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac)
235 {
236 	int ret;
237 	u8 tx_dly_val = 0;
238 
239 	switch (dwmac->phy_mode) {
240 	case PHY_INTERFACE_MODE_RGMII:
241 	case PHY_INTERFACE_MODE_RGMII_RXID:
242 		/* TX clock delay in ns = "8ns / 4 * tx_dly_val" (where
243 		 * 8ns are exactly one cycle of the 125MHz RGMII TX clock):
244 		 * 0ns = 0x0, 2ns = 0x1, 4ns = 0x2, 6ns = 0x3
245 		 */
246 		tx_dly_val = dwmac->tx_delay_ns >> 1;
247 		/* fall through */
248 
249 	case PHY_INTERFACE_MODE_RGMII_ID:
250 	case PHY_INTERFACE_MODE_RGMII_TXID:
251 		/* only relevant for RMII mode -> disable in RGMII mode */
252 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
253 					PRG_ETH0_INVERTED_RMII_CLK, 0);
254 
255 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TXDLY_MASK,
256 					tx_dly_val << PRG_ETH0_TXDLY_SHIFT);
257 
258 		/* Configure the 125MHz RGMII TX clock, the IP block changes
259 		 * the output automatically (= without us having to configure
260 		 * a register) based on the line-speed (125MHz for Gbit speeds,
261 		 * 25MHz for 100Mbit/s and 2.5MHz for 10Mbit/s).
262 		 */
263 		ret = clk_set_rate(dwmac->rgmii_tx_clk, 125 * 1000 * 1000);
264 		if (ret) {
265 			dev_err(dwmac->dev,
266 				"failed to set RGMII TX clock\n");
267 			return ret;
268 		}
269 
270 		ret = clk_prepare_enable(dwmac->rgmii_tx_clk);
271 		if (ret) {
272 			dev_err(dwmac->dev,
273 				"failed to enable the RGMII TX clock\n");
274 			return ret;
275 		}
276 
277 		devm_add_action_or_reset(dwmac->dev,
278 					(void(*)(void *))clk_disable_unprepare,
279 					dwmac->rgmii_tx_clk);
280 		break;
281 
282 	case PHY_INTERFACE_MODE_RMII:
283 		/* invert internal clk_rmii_i to generate 25/2.5 tx_rx_clk */
284 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
285 					PRG_ETH0_INVERTED_RMII_CLK,
286 					PRG_ETH0_INVERTED_RMII_CLK);
287 
288 		/* TX clock delay cannot be configured in RMII mode */
289 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TXDLY_MASK,
290 					0);
291 
292 		break;
293 
294 	default:
295 		dev_err(dwmac->dev, "unsupported phy-mode %s\n",
296 			phy_modes(dwmac->phy_mode));
297 		return -EINVAL;
298 	}
299 
300 	/* enable TX_CLK and PHY_REF_CLK generator */
301 	meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TX_AND_PHY_REF_CLK,
302 				PRG_ETH0_TX_AND_PHY_REF_CLK);
303 
304 	return 0;
305 }
306 
307 static int meson8b_dwmac_probe(struct platform_device *pdev)
308 {
309 	struct plat_stmmacenet_data *plat_dat;
310 	struct stmmac_resources stmmac_res;
311 	struct meson8b_dwmac *dwmac;
312 	int ret;
313 
314 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
315 	if (ret)
316 		return ret;
317 
318 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
319 	if (IS_ERR(plat_dat))
320 		return PTR_ERR(plat_dat);
321 
322 	dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
323 	if (!dwmac) {
324 		ret = -ENOMEM;
325 		goto err_remove_config_dt;
326 	}
327 
328 	dwmac->data = (const struct meson8b_dwmac_data *)
329 		of_device_get_match_data(&pdev->dev);
330 	if (!dwmac->data) {
331 		ret = -EINVAL;
332 		goto err_remove_config_dt;
333 	}
334 	dwmac->regs = devm_platform_ioremap_resource(pdev, 1);
335 	if (IS_ERR(dwmac->regs)) {
336 		ret = PTR_ERR(dwmac->regs);
337 		goto err_remove_config_dt;
338 	}
339 
340 	dwmac->dev = &pdev->dev;
341 	dwmac->phy_mode = of_get_phy_mode(pdev->dev.of_node);
342 	if ((int)dwmac->phy_mode < 0) {
343 		dev_err(&pdev->dev, "missing phy-mode property\n");
344 		ret = -EINVAL;
345 		goto err_remove_config_dt;
346 	}
347 
348 	/* use 2ns as fallback since this value was previously hardcoded */
349 	if (of_property_read_u32(pdev->dev.of_node, "amlogic,tx-delay-ns",
350 				 &dwmac->tx_delay_ns))
351 		dwmac->tx_delay_ns = 2;
352 
353 	ret = meson8b_init_rgmii_tx_clk(dwmac);
354 	if (ret)
355 		goto err_remove_config_dt;
356 
357 	ret = dwmac->data->set_phy_mode(dwmac);
358 	if (ret)
359 		goto err_remove_config_dt;
360 
361 	ret = meson8b_init_prg_eth(dwmac);
362 	if (ret)
363 		goto err_remove_config_dt;
364 
365 	plat_dat->bsp_priv = dwmac;
366 
367 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
368 	if (ret)
369 		goto err_remove_config_dt;
370 
371 	return 0;
372 
373 err_remove_config_dt:
374 	stmmac_remove_config_dt(pdev, plat_dat);
375 
376 	return ret;
377 }
378 
379 static const struct meson8b_dwmac_data meson8b_dwmac_data = {
380 	.set_phy_mode = meson8b_set_phy_mode,
381 };
382 
383 static const struct meson8b_dwmac_data meson_axg_dwmac_data = {
384 	.set_phy_mode = meson_axg_set_phy_mode,
385 };
386 
387 static const struct of_device_id meson8b_dwmac_match[] = {
388 	{
389 		.compatible = "amlogic,meson8b-dwmac",
390 		.data = &meson8b_dwmac_data,
391 	},
392 	{
393 		.compatible = "amlogic,meson8m2-dwmac",
394 		.data = &meson8b_dwmac_data,
395 	},
396 	{
397 		.compatible = "amlogic,meson-gxbb-dwmac",
398 		.data = &meson8b_dwmac_data,
399 	},
400 	{
401 		.compatible = "amlogic,meson-axg-dwmac",
402 		.data = &meson_axg_dwmac_data,
403 	},
404 	{ }
405 };
406 MODULE_DEVICE_TABLE(of, meson8b_dwmac_match);
407 
408 static struct platform_driver meson8b_dwmac_driver = {
409 	.probe  = meson8b_dwmac_probe,
410 	.remove = stmmac_pltfr_remove,
411 	.driver = {
412 		.name           = "meson8b-dwmac",
413 		.pm		= &stmmac_pltfr_pm_ops,
414 		.of_match_table = meson8b_dwmac_match,
415 	},
416 };
417 module_platform_driver(meson8b_dwmac_driver);
418 
419 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
420 MODULE_DESCRIPTION("Amlogic Meson8b, Meson8m2 and GXBB DWMAC glue layer");
421 MODULE_LICENSE("GPL v2");
422