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 	static const struct clk_div_table div_table[] = {
116 		{ .div = 2, .val = 2, },
117 		{ .div = 3, .val = 3, },
118 		{ .div = 4, .val = 4, },
119 		{ .div = 5, .val = 5, },
120 		{ .div = 6, .val = 6, },
121 		{ .div = 7, .val = 7, },
122 	};
123 
124 	clk_configs = devm_kzalloc(dev, sizeof(*clk_configs), GFP_KERNEL);
125 	if (!clk_configs)
126 		return -ENOMEM;
127 
128 	/* get the mux parents from DT */
129 	for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
130 		char name[16];
131 
132 		snprintf(name, sizeof(name), "clkin%d", i);
133 		clk = devm_clk_get(dev, name);
134 		if (IS_ERR(clk)) {
135 			ret = PTR_ERR(clk);
136 			if (ret != -EPROBE_DEFER)
137 				dev_err(dev, "Missing clock %s\n", name);
138 			return ret;
139 		}
140 
141 		mux_parent_names[i] = __clk_get_name(clk);
142 	}
143 
144 	clk_configs->m250_mux.reg = dwmac->regs + PRG_ETH0;
145 	clk_configs->m250_mux.shift = PRG_ETH0_CLK_M250_SEL_SHIFT;
146 	clk_configs->m250_mux.mask = PRG_ETH0_CLK_M250_SEL_MASK;
147 	clk = meson8b_dwmac_register_clk(dwmac, "m250_sel", mux_parent_names,
148 					 MUX_CLK_NUM_PARENTS, &clk_mux_ops,
149 					 &clk_configs->m250_mux.hw);
150 	if (WARN_ON(IS_ERR(clk)))
151 		return PTR_ERR(clk);
152 
153 	parent_name = __clk_get_name(clk);
154 	clk_configs->m250_div.reg = dwmac->regs + PRG_ETH0;
155 	clk_configs->m250_div.shift = PRG_ETH0_CLK_M250_DIV_SHIFT;
156 	clk_configs->m250_div.width = PRG_ETH0_CLK_M250_DIV_WIDTH;
157 	clk_configs->m250_div.table = div_table;
158 	clk_configs->m250_div.flags = CLK_DIVIDER_ALLOW_ZERO |
159 				      CLK_DIVIDER_ROUND_CLOSEST;
160 	clk = meson8b_dwmac_register_clk(dwmac, "m250_div", &parent_name, 1,
161 					 &clk_divider_ops,
162 					 &clk_configs->m250_div.hw);
163 	if (WARN_ON(IS_ERR(clk)))
164 		return PTR_ERR(clk);
165 
166 	parent_name = __clk_get_name(clk);
167 	clk_configs->fixed_div2.mult = 1;
168 	clk_configs->fixed_div2.div = 2;
169 	clk = meson8b_dwmac_register_clk(dwmac, "fixed_div2", &parent_name, 1,
170 					 &clk_fixed_factor_ops,
171 					 &clk_configs->fixed_div2.hw);
172 	if (WARN_ON(IS_ERR(clk)))
173 		return PTR_ERR(clk);
174 
175 	parent_name = __clk_get_name(clk);
176 	clk_configs->rgmii_tx_en.reg = dwmac->regs + PRG_ETH0;
177 	clk_configs->rgmii_tx_en.bit_idx = PRG_ETH0_RGMII_TX_CLK_EN;
178 	clk = meson8b_dwmac_register_clk(dwmac, "rgmii_tx_en", &parent_name, 1,
179 					 &clk_gate_ops,
180 					 &clk_configs->rgmii_tx_en.hw);
181 	if (WARN_ON(IS_ERR(clk)))
182 		return PTR_ERR(clk);
183 
184 	dwmac->rgmii_tx_clk = clk;
185 
186 	return 0;
187 }
188 
189 static int meson8b_set_phy_mode(struct meson8b_dwmac *dwmac)
190 {
191 	switch (dwmac->phy_mode) {
192 	case PHY_INTERFACE_MODE_RGMII:
193 	case PHY_INTERFACE_MODE_RGMII_RXID:
194 	case PHY_INTERFACE_MODE_RGMII_ID:
195 	case PHY_INTERFACE_MODE_RGMII_TXID:
196 		/* enable RGMII mode */
197 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
198 					PRG_ETH0_RGMII_MODE,
199 					PRG_ETH0_RGMII_MODE);
200 		break;
201 	case PHY_INTERFACE_MODE_RMII:
202 		/* disable RGMII mode -> enables RMII mode */
203 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
204 					PRG_ETH0_RGMII_MODE, 0);
205 		break;
206 	default:
207 		dev_err(dwmac->dev, "fail to set phy-mode %s\n",
208 			phy_modes(dwmac->phy_mode));
209 		return -EINVAL;
210 	}
211 
212 	return 0;
213 }
214 
215 static int meson_axg_set_phy_mode(struct meson8b_dwmac *dwmac)
216 {
217 	switch (dwmac->phy_mode) {
218 	case PHY_INTERFACE_MODE_RGMII:
219 	case PHY_INTERFACE_MODE_RGMII_RXID:
220 	case PHY_INTERFACE_MODE_RGMII_ID:
221 	case PHY_INTERFACE_MODE_RGMII_TXID:
222 		/* enable RGMII mode */
223 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
224 					PRG_ETH0_EXT_PHY_MODE_MASK,
225 					PRG_ETH0_EXT_RGMII_MODE);
226 		break;
227 	case PHY_INTERFACE_MODE_RMII:
228 		/* disable RGMII mode -> enables RMII mode */
229 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
230 					PRG_ETH0_EXT_PHY_MODE_MASK,
231 					PRG_ETH0_EXT_RMII_MODE);
232 		break;
233 	default:
234 		dev_err(dwmac->dev, "fail to set phy-mode %s\n",
235 			phy_modes(dwmac->phy_mode));
236 		return -EINVAL;
237 	}
238 
239 	return 0;
240 }
241 
242 static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac)
243 {
244 	int ret;
245 	u8 tx_dly_val = 0;
246 
247 	switch (dwmac->phy_mode) {
248 	case PHY_INTERFACE_MODE_RGMII:
249 	case PHY_INTERFACE_MODE_RGMII_RXID:
250 		/* TX clock delay in ns = "8ns / 4 * tx_dly_val" (where
251 		 * 8ns are exactly one cycle of the 125MHz RGMII TX clock):
252 		 * 0ns = 0x0, 2ns = 0x1, 4ns = 0x2, 6ns = 0x3
253 		 */
254 		tx_dly_val = dwmac->tx_delay_ns >> 1;
255 		/* fall through */
256 
257 	case PHY_INTERFACE_MODE_RGMII_ID:
258 	case PHY_INTERFACE_MODE_RGMII_TXID:
259 		/* only relevant for RMII mode -> disable in RGMII mode */
260 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
261 					PRG_ETH0_INVERTED_RMII_CLK, 0);
262 
263 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TXDLY_MASK,
264 					tx_dly_val << PRG_ETH0_TXDLY_SHIFT);
265 
266 		/* Configure the 125MHz RGMII TX clock, the IP block changes
267 		 * the output automatically (= without us having to configure
268 		 * a register) based on the line-speed (125MHz for Gbit speeds,
269 		 * 25MHz for 100Mbit/s and 2.5MHz for 10Mbit/s).
270 		 */
271 		ret = clk_set_rate(dwmac->rgmii_tx_clk, 125 * 1000 * 1000);
272 		if (ret) {
273 			dev_err(dwmac->dev,
274 				"failed to set RGMII TX clock\n");
275 			return ret;
276 		}
277 
278 		ret = clk_prepare_enable(dwmac->rgmii_tx_clk);
279 		if (ret) {
280 			dev_err(dwmac->dev,
281 				"failed to enable the RGMII TX clock\n");
282 			return ret;
283 		}
284 
285 		devm_add_action_or_reset(dwmac->dev,
286 					(void(*)(void *))clk_disable_unprepare,
287 					dwmac->rgmii_tx_clk);
288 		break;
289 
290 	case PHY_INTERFACE_MODE_RMII:
291 		/* invert internal clk_rmii_i to generate 25/2.5 tx_rx_clk */
292 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0,
293 					PRG_ETH0_INVERTED_RMII_CLK,
294 					PRG_ETH0_INVERTED_RMII_CLK);
295 
296 		/* TX clock delay cannot be configured in RMII mode */
297 		meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TXDLY_MASK,
298 					0);
299 
300 		break;
301 
302 	default:
303 		dev_err(dwmac->dev, "unsupported phy-mode %s\n",
304 			phy_modes(dwmac->phy_mode));
305 		return -EINVAL;
306 	}
307 
308 	/* enable TX_CLK and PHY_REF_CLK generator */
309 	meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TX_AND_PHY_REF_CLK,
310 				PRG_ETH0_TX_AND_PHY_REF_CLK);
311 
312 	return 0;
313 }
314 
315 static int meson8b_dwmac_probe(struct platform_device *pdev)
316 {
317 	struct plat_stmmacenet_data *plat_dat;
318 	struct stmmac_resources stmmac_res;
319 	struct meson8b_dwmac *dwmac;
320 	int ret;
321 
322 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
323 	if (ret)
324 		return ret;
325 
326 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
327 	if (IS_ERR(plat_dat))
328 		return PTR_ERR(plat_dat);
329 
330 	dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
331 	if (!dwmac) {
332 		ret = -ENOMEM;
333 		goto err_remove_config_dt;
334 	}
335 
336 	dwmac->data = (const struct meson8b_dwmac_data *)
337 		of_device_get_match_data(&pdev->dev);
338 	if (!dwmac->data) {
339 		ret = -EINVAL;
340 		goto err_remove_config_dt;
341 	}
342 	dwmac->regs = devm_platform_ioremap_resource(pdev, 1);
343 	if (IS_ERR(dwmac->regs)) {
344 		ret = PTR_ERR(dwmac->regs);
345 		goto err_remove_config_dt;
346 	}
347 
348 	dwmac->dev = &pdev->dev;
349 	ret = of_get_phy_mode(pdev->dev.of_node, &dwmac->phy_mode);
350 	if (ret) {
351 		dev_err(&pdev->dev, "missing phy-mode property\n");
352 		goto err_remove_config_dt;
353 	}
354 
355 	/* use 2ns as fallback since this value was previously hardcoded */
356 	if (of_property_read_u32(pdev->dev.of_node, "amlogic,tx-delay-ns",
357 				 &dwmac->tx_delay_ns))
358 		dwmac->tx_delay_ns = 2;
359 
360 	ret = meson8b_init_rgmii_tx_clk(dwmac);
361 	if (ret)
362 		goto err_remove_config_dt;
363 
364 	ret = dwmac->data->set_phy_mode(dwmac);
365 	if (ret)
366 		goto err_remove_config_dt;
367 
368 	ret = meson8b_init_prg_eth(dwmac);
369 	if (ret)
370 		goto err_remove_config_dt;
371 
372 	plat_dat->bsp_priv = dwmac;
373 
374 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
375 	if (ret)
376 		goto err_remove_config_dt;
377 
378 	return 0;
379 
380 err_remove_config_dt:
381 	stmmac_remove_config_dt(pdev, plat_dat);
382 
383 	return ret;
384 }
385 
386 static const struct meson8b_dwmac_data meson8b_dwmac_data = {
387 	.set_phy_mode = meson8b_set_phy_mode,
388 };
389 
390 static const struct meson8b_dwmac_data meson_axg_dwmac_data = {
391 	.set_phy_mode = meson_axg_set_phy_mode,
392 };
393 
394 static const struct of_device_id meson8b_dwmac_match[] = {
395 	{
396 		.compatible = "amlogic,meson8b-dwmac",
397 		.data = &meson8b_dwmac_data,
398 	},
399 	{
400 		.compatible = "amlogic,meson8m2-dwmac",
401 		.data = &meson8b_dwmac_data,
402 	},
403 	{
404 		.compatible = "amlogic,meson-gxbb-dwmac",
405 		.data = &meson8b_dwmac_data,
406 	},
407 	{
408 		.compatible = "amlogic,meson-axg-dwmac",
409 		.data = &meson_axg_dwmac_data,
410 	},
411 	{ }
412 };
413 MODULE_DEVICE_TABLE(of, meson8b_dwmac_match);
414 
415 static struct platform_driver meson8b_dwmac_driver = {
416 	.probe  = meson8b_dwmac_probe,
417 	.remove = stmmac_pltfr_remove,
418 	.driver = {
419 		.name           = "meson8b-dwmac",
420 		.pm		= &stmmac_pltfr_pm_ops,
421 		.of_match_table = meson8b_dwmac_match,
422 	},
423 };
424 module_platform_driver(meson8b_dwmac_driver);
425 
426 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
427 MODULE_DESCRIPTION("Amlogic Meson8b, Meson8m2 and GXBB DWMAC glue layer");
428 MODULE_LICENSE("GPL v2");
429