1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * dwmac-sunxi.c - Allwinner sunxi DWMAC specific glue layer
4  *
5  * Copyright (C) 2013 Chen-Yu Tsai
6  *
7  * Chen-Yu Tsai  <wens@csie.org>
8  */
9 
10 #include <linux/stmmac.h>
11 #include <linux/clk.h>
12 #include <linux/module.h>
13 #include <linux/phy.h>
14 #include <linux/platform_device.h>
15 #include <linux/of_net.h>
16 #include <linux/regulator/consumer.h>
17 
18 #include "stmmac_platform.h"
19 
20 struct sunxi_priv_data {
21 	phy_interface_t interface;
22 	int clk_enabled;
23 	struct clk *tx_clk;
24 	struct regulator *regulator;
25 };
26 
27 #define SUN7I_GMAC_GMII_RGMII_RATE	125000000
28 #define SUN7I_GMAC_MII_RATE		25000000
29 
sun7i_gmac_init(struct platform_device * pdev,void * priv)30 static int sun7i_gmac_init(struct platform_device *pdev, void *priv)
31 {
32 	struct sunxi_priv_data *gmac = priv;
33 	int ret = 0;
34 
35 	if (gmac->regulator) {
36 		ret = regulator_enable(gmac->regulator);
37 		if (ret)
38 			return ret;
39 	}
40 
41 	/* Set GMAC interface port mode
42 	 *
43 	 * The GMAC TX clock lines are configured by setting the clock
44 	 * rate, which then uses the auto-reparenting feature of the
45 	 * clock driver, and enabling/disabling the clock.
46 	 */
47 	if (phy_interface_mode_is_rgmii(gmac->interface)) {
48 		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
49 		clk_prepare_enable(gmac->tx_clk);
50 		gmac->clk_enabled = 1;
51 	} else {
52 		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
53 		ret = clk_prepare(gmac->tx_clk);
54 		if (ret && gmac->regulator)
55 			regulator_disable(gmac->regulator);
56 	}
57 
58 	return ret;
59 }
60 
sun7i_gmac_exit(struct platform_device * pdev,void * priv)61 static void sun7i_gmac_exit(struct platform_device *pdev, void *priv)
62 {
63 	struct sunxi_priv_data *gmac = priv;
64 
65 	if (gmac->clk_enabled) {
66 		clk_disable(gmac->tx_clk);
67 		gmac->clk_enabled = 0;
68 	}
69 	clk_unprepare(gmac->tx_clk);
70 
71 	if (gmac->regulator)
72 		regulator_disable(gmac->regulator);
73 }
74 
sun7i_fix_speed(void * priv,unsigned int speed)75 static void sun7i_fix_speed(void *priv, unsigned int speed)
76 {
77 	struct sunxi_priv_data *gmac = priv;
78 
79 	/* only GMII mode requires us to reconfigure the clock lines */
80 	if (gmac->interface != PHY_INTERFACE_MODE_GMII)
81 		return;
82 
83 	if (gmac->clk_enabled) {
84 		clk_disable(gmac->tx_clk);
85 		gmac->clk_enabled = 0;
86 	}
87 	clk_unprepare(gmac->tx_clk);
88 
89 	if (speed == 1000) {
90 		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
91 		clk_prepare_enable(gmac->tx_clk);
92 		gmac->clk_enabled = 1;
93 	} else {
94 		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
95 		clk_prepare(gmac->tx_clk);
96 	}
97 }
98 
sun7i_gmac_probe(struct platform_device * pdev)99 static int sun7i_gmac_probe(struct platform_device *pdev)
100 {
101 	struct plat_stmmacenet_data *plat_dat;
102 	struct stmmac_resources stmmac_res;
103 	struct sunxi_priv_data *gmac;
104 	struct device *dev = &pdev->dev;
105 	int ret;
106 
107 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
108 	if (ret)
109 		return ret;
110 
111 	plat_dat = stmmac_probe_config_dt(pdev, stmmac_res.mac);
112 	if (IS_ERR(plat_dat))
113 		return PTR_ERR(plat_dat);
114 
115 	gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL);
116 	if (!gmac) {
117 		ret = -ENOMEM;
118 		goto err_remove_config_dt;
119 	}
120 
121 	ret = of_get_phy_mode(dev->of_node, &gmac->interface);
122 	if (ret && ret != -ENODEV) {
123 		dev_err(dev, "Can't get phy-mode\n");
124 		goto err_remove_config_dt;
125 	}
126 
127 	gmac->tx_clk = devm_clk_get(dev, "allwinner_gmac_tx");
128 	if (IS_ERR(gmac->tx_clk)) {
129 		dev_err(dev, "could not get tx clock\n");
130 		ret = PTR_ERR(gmac->tx_clk);
131 		goto err_remove_config_dt;
132 	}
133 
134 	/* Optional regulator for PHY */
135 	gmac->regulator = devm_regulator_get_optional(dev, "phy");
136 	if (IS_ERR(gmac->regulator)) {
137 		if (PTR_ERR(gmac->regulator) == -EPROBE_DEFER) {
138 			ret = -EPROBE_DEFER;
139 			goto err_remove_config_dt;
140 		}
141 		dev_info(dev, "no regulator found\n");
142 		gmac->regulator = NULL;
143 	}
144 
145 	/* platform data specifying hardware features and callbacks.
146 	 * hardware features were copied from Allwinner drivers. */
147 	plat_dat->tx_coe = 1;
148 	plat_dat->has_gmac = true;
149 	plat_dat->bsp_priv = gmac;
150 	plat_dat->init = sun7i_gmac_init;
151 	plat_dat->exit = sun7i_gmac_exit;
152 	plat_dat->fix_mac_speed = sun7i_fix_speed;
153 	plat_dat->tx_fifo_size = 4096;
154 	plat_dat->rx_fifo_size = 16384;
155 
156 	ret = sun7i_gmac_init(pdev, plat_dat->bsp_priv);
157 	if (ret)
158 		goto err_remove_config_dt;
159 
160 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
161 	if (ret)
162 		goto err_gmac_exit;
163 
164 	return 0;
165 
166 err_gmac_exit:
167 	sun7i_gmac_exit(pdev, plat_dat->bsp_priv);
168 err_remove_config_dt:
169 	stmmac_remove_config_dt(pdev, plat_dat);
170 
171 	return ret;
172 }
173 
174 static const struct of_device_id sun7i_dwmac_match[] = {
175 	{ .compatible = "allwinner,sun7i-a20-gmac" },
176 	{ }
177 };
178 MODULE_DEVICE_TABLE(of, sun7i_dwmac_match);
179 
180 static struct platform_driver sun7i_dwmac_driver = {
181 	.probe  = sun7i_gmac_probe,
182 	.remove = stmmac_pltfr_remove,
183 	.driver = {
184 		.name           = "sun7i-dwmac",
185 		.pm		= &stmmac_pltfr_pm_ops,
186 		.of_match_table = sun7i_dwmac_match,
187 	},
188 };
189 module_platform_driver(sun7i_dwmac_driver);
190 
191 MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
192 MODULE_DESCRIPTION("Allwinner sunxi DWMAC specific glue layer");
193 MODULE_LICENSE("GPL");
194