1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Oxford Semiconductor OXNAS DWMAC glue layer
4  *
5  * Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com>
6  * Copyright (C) 2014 Daniel Golle <daniel@makrotopia.org>
7  * Copyright (C) 2013 Ma Haijun <mahaijuns@gmail.com>
8  * Copyright (C) 2012 John Crispin <blogic@openwrt.org>
9  */
10 
11 #include <linux/device.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_device.h>
16 #include <linux/platform_device.h>
17 #include <linux/regmap.h>
18 #include <linux/mfd/syscon.h>
19 #include <linux/stmmac.h>
20 
21 #include "stmmac_platform.h"
22 
23 /* System Control regmap offsets */
24 #define OXNAS_DWMAC_CTRL_REGOFFSET	0x78
25 #define OXNAS_DWMAC_DELAY_REGOFFSET	0x100
26 
27 /* Control Register */
28 #define DWMAC_CKEN_RX_IN        14
29 #define DWMAC_CKEN_RXN_OUT      13
30 #define DWMAC_CKEN_RX_OUT       12
31 #define DWMAC_CKEN_TX_IN        10
32 #define DWMAC_CKEN_TXN_OUT      9
33 #define DWMAC_CKEN_TX_OUT       8
34 #define DWMAC_RX_SOURCE         7
35 #define DWMAC_TX_SOURCE         6
36 #define DWMAC_LOW_TX_SOURCE     4
37 #define DWMAC_AUTO_TX_SOURCE    3
38 #define DWMAC_RGMII             2
39 #define DWMAC_SIMPLE_MUX        1
40 #define DWMAC_CKEN_GTX          0
41 
42 /* Delay register */
43 #define DWMAC_TX_VARDELAY_SHIFT		0
44 #define DWMAC_TXN_VARDELAY_SHIFT	8
45 #define DWMAC_RX_VARDELAY_SHIFT		16
46 #define DWMAC_RXN_VARDELAY_SHIFT	24
47 #define DWMAC_TX_VARDELAY(d)		((d) << DWMAC_TX_VARDELAY_SHIFT)
48 #define DWMAC_TXN_VARDELAY(d)		((d) << DWMAC_TXN_VARDELAY_SHIFT)
49 #define DWMAC_RX_VARDELAY(d)		((d) << DWMAC_RX_VARDELAY_SHIFT)
50 #define DWMAC_RXN_VARDELAY(d)		((d) << DWMAC_RXN_VARDELAY_SHIFT)
51 
52 struct oxnas_dwmac;
53 
54 struct oxnas_dwmac_data {
55 	int (*setup)(struct oxnas_dwmac *dwmac);
56 };
57 
58 struct oxnas_dwmac {
59 	struct device	*dev;
60 	struct clk	*clk;
61 	struct regmap	*regmap;
62 	const struct oxnas_dwmac_data	*data;
63 };
64 
oxnas_dwmac_setup_ox810se(struct oxnas_dwmac * dwmac)65 static int oxnas_dwmac_setup_ox810se(struct oxnas_dwmac *dwmac)
66 {
67 	unsigned int value;
68 	int ret;
69 
70 	ret = regmap_read(dwmac->regmap, OXNAS_DWMAC_CTRL_REGOFFSET, &value);
71 	if (ret < 0)
72 		return ret;
73 
74 	/* Enable GMII_GTXCLK to follow GMII_REFCLK, required for gigabit PHY */
75 	value |= BIT(DWMAC_CKEN_GTX)		|
76 		 /* Use simple mux for 25/125 Mhz clock switching */
77 		 BIT(DWMAC_SIMPLE_MUX);
78 
79 	regmap_write(dwmac->regmap, OXNAS_DWMAC_CTRL_REGOFFSET, value);
80 
81 	return 0;
82 }
83 
oxnas_dwmac_setup_ox820(struct oxnas_dwmac * dwmac)84 static int oxnas_dwmac_setup_ox820(struct oxnas_dwmac *dwmac)
85 {
86 	unsigned int value;
87 	int ret;
88 
89 	ret = regmap_read(dwmac->regmap, OXNAS_DWMAC_CTRL_REGOFFSET, &value);
90 	if (ret < 0)
91 		return ret;
92 
93 	/* Enable GMII_GTXCLK to follow GMII_REFCLK, required for gigabit PHY */
94 	value |= BIT(DWMAC_CKEN_GTX)		|
95 		 /* Use simple mux for 25/125 Mhz clock switching */
96 		BIT(DWMAC_SIMPLE_MUX)		|
97 		/* set auto switch tx clock source */
98 		BIT(DWMAC_AUTO_TX_SOURCE)	|
99 		/* enable tx & rx vardelay */
100 		BIT(DWMAC_CKEN_TX_OUT)		|
101 		BIT(DWMAC_CKEN_TXN_OUT)	|
102 		BIT(DWMAC_CKEN_TX_IN)		|
103 		BIT(DWMAC_CKEN_RX_OUT)		|
104 		BIT(DWMAC_CKEN_RXN_OUT)	|
105 		BIT(DWMAC_CKEN_RX_IN);
106 	regmap_write(dwmac->regmap, OXNAS_DWMAC_CTRL_REGOFFSET, value);
107 
108 	/* set tx & rx vardelay */
109 	value = DWMAC_TX_VARDELAY(4)	|
110 		DWMAC_TXN_VARDELAY(2)	|
111 		DWMAC_RX_VARDELAY(10)	|
112 		DWMAC_RXN_VARDELAY(8);
113 	regmap_write(dwmac->regmap, OXNAS_DWMAC_DELAY_REGOFFSET, value);
114 
115 	return 0;
116 }
117 
oxnas_dwmac_init(struct platform_device * pdev,void * priv)118 static int oxnas_dwmac_init(struct platform_device *pdev, void *priv)
119 {
120 	struct oxnas_dwmac *dwmac = priv;
121 	int ret;
122 
123 	/* Reset HW here before changing the glue configuration */
124 	ret = device_reset(dwmac->dev);
125 	if (ret)
126 		return ret;
127 
128 	ret = clk_prepare_enable(dwmac->clk);
129 	if (ret)
130 		return ret;
131 
132 	ret = dwmac->data->setup(dwmac);
133 	if (ret)
134 		clk_disable_unprepare(dwmac->clk);
135 
136 	return ret;
137 }
138 
oxnas_dwmac_exit(struct platform_device * pdev,void * priv)139 static void oxnas_dwmac_exit(struct platform_device *pdev, void *priv)
140 {
141 	struct oxnas_dwmac *dwmac = priv;
142 
143 	clk_disable_unprepare(dwmac->clk);
144 }
145 
oxnas_dwmac_probe(struct platform_device * pdev)146 static int oxnas_dwmac_probe(struct platform_device *pdev)
147 {
148 	struct plat_stmmacenet_data *plat_dat;
149 	struct stmmac_resources stmmac_res;
150 	struct oxnas_dwmac *dwmac;
151 	int ret;
152 
153 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
154 	if (ret)
155 		return ret;
156 
157 	plat_dat = stmmac_probe_config_dt(pdev, stmmac_res.mac);
158 	if (IS_ERR(plat_dat))
159 		return PTR_ERR(plat_dat);
160 
161 	dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
162 	if (!dwmac) {
163 		ret = -ENOMEM;
164 		goto err_remove_config_dt;
165 	}
166 
167 	dwmac->data = (const struct oxnas_dwmac_data *)of_device_get_match_data(&pdev->dev);
168 	if (!dwmac->data) {
169 		ret = -EINVAL;
170 		goto err_remove_config_dt;
171 	}
172 
173 	dwmac->dev = &pdev->dev;
174 	plat_dat->bsp_priv = dwmac;
175 	plat_dat->init = oxnas_dwmac_init;
176 	plat_dat->exit = oxnas_dwmac_exit;
177 
178 	dwmac->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
179 							"oxsemi,sys-ctrl");
180 	if (IS_ERR(dwmac->regmap)) {
181 		dev_err(&pdev->dev, "failed to have sysctrl regmap\n");
182 		ret = PTR_ERR(dwmac->regmap);
183 		goto err_remove_config_dt;
184 	}
185 
186 	dwmac->clk = devm_clk_get(&pdev->dev, "gmac");
187 	if (IS_ERR(dwmac->clk)) {
188 		ret = PTR_ERR(dwmac->clk);
189 		goto err_remove_config_dt;
190 	}
191 
192 	ret = oxnas_dwmac_init(pdev, plat_dat->bsp_priv);
193 	if (ret)
194 		goto err_remove_config_dt;
195 
196 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
197 	if (ret)
198 		goto err_dwmac_exit;
199 
200 
201 	return 0;
202 
203 err_dwmac_exit:
204 	oxnas_dwmac_exit(pdev, plat_dat->bsp_priv);
205 err_remove_config_dt:
206 	stmmac_remove_config_dt(pdev, plat_dat);
207 
208 	return ret;
209 }
210 
211 static const struct oxnas_dwmac_data ox810se_dwmac_data = {
212 	.setup = oxnas_dwmac_setup_ox810se,
213 };
214 
215 static const struct oxnas_dwmac_data ox820_dwmac_data = {
216 	.setup = oxnas_dwmac_setup_ox820,
217 };
218 
219 static const struct of_device_id oxnas_dwmac_match[] = {
220 	{
221 		.compatible = "oxsemi,ox810se-dwmac",
222 		.data = &ox810se_dwmac_data,
223 	},
224 	{
225 		.compatible = "oxsemi,ox820-dwmac",
226 		.data = &ox820_dwmac_data,
227 	},
228 	{ }
229 };
230 MODULE_DEVICE_TABLE(of, oxnas_dwmac_match);
231 
232 static struct platform_driver oxnas_dwmac_driver = {
233 	.probe  = oxnas_dwmac_probe,
234 	.remove = stmmac_pltfr_remove,
235 	.driver = {
236 		.name           = "oxnas-dwmac",
237 		.pm		= &stmmac_pltfr_pm_ops,
238 		.of_match_table = oxnas_dwmac_match,
239 	},
240 };
241 module_platform_driver(oxnas_dwmac_driver);
242 
243 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
244 MODULE_DESCRIPTION("Oxford Semiconductor OXNAS DWMAC glue layer");
245 MODULE_LICENSE("GPL v2");
246