1 /*
2 * dwmac-sunxi.c - Allwinner sunxi DWMAC specific glue layer
3 *
4 * Copyright (C) 2013 Chen-Yu Tsai
5 *
6 * Chen-Yu Tsai <wens@csie.org>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 */
18
19 #include <linux/stmmac.h>
20 #include <linux/clk.h>
21 #include <linux/module.h>
22 #include <linux/phy.h>
23 #include <linux/platform_device.h>
24 #include <linux/of_net.h>
25 #include <linux/regulator/consumer.h>
26
27 #include "stmmac_platform.h"
28
29 struct sunxi_priv_data {
30 int interface;
31 int clk_enabled;
32 struct clk *tx_clk;
33 struct regulator *regulator;
34 };
35
36 #define SUN7I_GMAC_GMII_RGMII_RATE 125000000
37 #define SUN7I_GMAC_MII_RATE 25000000
38
sun7i_gmac_init(struct platform_device * pdev,void * priv)39 static int sun7i_gmac_init(struct platform_device *pdev, void *priv)
40 {
41 struct sunxi_priv_data *gmac = priv;
42 int ret;
43
44 if (gmac->regulator) {
45 ret = regulator_enable(gmac->regulator);
46 if (ret)
47 return ret;
48 }
49
50 /* Set GMAC interface port mode
51 *
52 * The GMAC TX clock lines are configured by setting the clock
53 * rate, which then uses the auto-reparenting feature of the
54 * clock driver, and enabling/disabling the clock.
55 */
56 if (phy_interface_mode_is_rgmii(gmac->interface)) {
57 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
58 clk_prepare_enable(gmac->tx_clk);
59 gmac->clk_enabled = 1;
60 } else {
61 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
62 ret = clk_prepare(gmac->tx_clk);
63 if (ret)
64 return ret;
65 }
66
67 return 0;
68 }
69
sun7i_gmac_exit(struct platform_device * pdev,void * priv)70 static void sun7i_gmac_exit(struct platform_device *pdev, void *priv)
71 {
72 struct sunxi_priv_data *gmac = priv;
73
74 if (gmac->clk_enabled) {
75 clk_disable(gmac->tx_clk);
76 gmac->clk_enabled = 0;
77 }
78 clk_unprepare(gmac->tx_clk);
79
80 if (gmac->regulator)
81 regulator_disable(gmac->regulator);
82 }
83
sun7i_fix_speed(void * priv,unsigned int speed)84 static void sun7i_fix_speed(void *priv, unsigned int speed)
85 {
86 struct sunxi_priv_data *gmac = priv;
87
88 /* only GMII mode requires us to reconfigure the clock lines */
89 if (gmac->interface != PHY_INTERFACE_MODE_GMII)
90 return;
91
92 if (gmac->clk_enabled) {
93 clk_disable(gmac->tx_clk);
94 gmac->clk_enabled = 0;
95 }
96 clk_unprepare(gmac->tx_clk);
97
98 if (speed == 1000) {
99 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
100 clk_prepare_enable(gmac->tx_clk);
101 gmac->clk_enabled = 1;
102 } else {
103 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
104 clk_prepare(gmac->tx_clk);
105 }
106 }
107
sun7i_gmac_probe(struct platform_device * pdev)108 static int sun7i_gmac_probe(struct platform_device *pdev)
109 {
110 struct plat_stmmacenet_data *plat_dat;
111 struct stmmac_resources stmmac_res;
112 struct sunxi_priv_data *gmac;
113 struct device *dev = &pdev->dev;
114 int ret;
115
116 ret = stmmac_get_platform_resources(pdev, &stmmac_res);
117 if (ret)
118 return ret;
119
120 plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
121 if (IS_ERR(plat_dat))
122 return PTR_ERR(plat_dat);
123
124 gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL);
125 if (!gmac) {
126 ret = -ENOMEM;
127 goto err_remove_config_dt;
128 }
129
130 gmac->interface = of_get_phy_mode(dev->of_node);
131
132 gmac->tx_clk = devm_clk_get(dev, "allwinner_gmac_tx");
133 if (IS_ERR(gmac->tx_clk)) {
134 dev_err(dev, "could not get tx clock\n");
135 ret = PTR_ERR(gmac->tx_clk);
136 goto err_remove_config_dt;
137 }
138
139 /* Optional regulator for PHY */
140 gmac->regulator = devm_regulator_get_optional(dev, "phy");
141 if (IS_ERR(gmac->regulator)) {
142 if (PTR_ERR(gmac->regulator) == -EPROBE_DEFER) {
143 ret = -EPROBE_DEFER;
144 goto err_remove_config_dt;
145 }
146 dev_info(dev, "no regulator found\n");
147 gmac->regulator = NULL;
148 }
149
150 /* platform data specifying hardware features and callbacks.
151 * hardware features were copied from Allwinner drivers. */
152 plat_dat->tx_coe = 1;
153 plat_dat->has_gmac = true;
154 plat_dat->bsp_priv = gmac;
155 plat_dat->init = sun7i_gmac_init;
156 plat_dat->exit = sun7i_gmac_exit;
157 plat_dat->fix_mac_speed = sun7i_fix_speed;
158 plat_dat->tx_fifo_size = 4096;
159 plat_dat->rx_fifo_size = 16384;
160
161 ret = sun7i_gmac_init(pdev, plat_dat->bsp_priv);
162 if (ret)
163 goto err_remove_config_dt;
164
165 ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
166 if (ret)
167 goto err_gmac_exit;
168
169 return 0;
170
171 err_gmac_exit:
172 sun7i_gmac_exit(pdev, plat_dat->bsp_priv);
173 err_remove_config_dt:
174 stmmac_remove_config_dt(pdev, plat_dat);
175
176 return ret;
177 }
178
179 static const struct of_device_id sun7i_dwmac_match[] = {
180 { .compatible = "allwinner,sun7i-a20-gmac" },
181 { }
182 };
183 MODULE_DEVICE_TABLE(of, sun7i_dwmac_match);
184
185 static struct platform_driver sun7i_dwmac_driver = {
186 .probe = sun7i_gmac_probe,
187 .remove = stmmac_pltfr_remove,
188 .driver = {
189 .name = "sun7i-dwmac",
190 .pm = &stmmac_pltfr_pm_ops,
191 .of_match_table = sun7i_dwmac_match,
192 },
193 };
194 module_platform_driver(sun7i_dwmac_driver);
195
196 MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
197 MODULE_DESCRIPTION("Allwinner sunxi DWMAC specific glue layer");
198 MODULE_LICENSE("GPL");
199