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/phy.h>
22 #include <linux/of_net.h>
23 #include <linux/regulator/consumer.h>
24
25 #include "stmmac_platform.h"
26
27 struct sunxi_priv_data {
28 int interface;
29 int clk_enabled;
30 struct clk *tx_clk;
31 struct regulator *regulator;
32 };
33
sun7i_gmac_setup(struct platform_device * pdev)34 static void *sun7i_gmac_setup(struct platform_device *pdev)
35 {
36 struct sunxi_priv_data *gmac;
37 struct device *dev = &pdev->dev;
38
39 gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL);
40 if (!gmac)
41 return ERR_PTR(-ENOMEM);
42
43 gmac->interface = of_get_phy_mode(dev->of_node);
44
45 gmac->tx_clk = devm_clk_get(dev, "allwinner_gmac_tx");
46 if (IS_ERR(gmac->tx_clk)) {
47 dev_err(dev, "could not get tx clock\n");
48 return gmac->tx_clk;
49 }
50
51 /* Optional regulator for PHY */
52 gmac->regulator = devm_regulator_get_optional(dev, "phy");
53 if (IS_ERR(gmac->regulator)) {
54 if (PTR_ERR(gmac->regulator) == -EPROBE_DEFER)
55 return ERR_PTR(-EPROBE_DEFER);
56 dev_info(dev, "no regulator found\n");
57 gmac->regulator = NULL;
58 }
59
60 return gmac;
61 }
62
63 #define SUN7I_GMAC_GMII_RGMII_RATE 125000000
64 #define SUN7I_GMAC_MII_RATE 25000000
65
sun7i_gmac_init(struct platform_device * pdev,void * priv)66 static int sun7i_gmac_init(struct platform_device *pdev, void *priv)
67 {
68 struct sunxi_priv_data *gmac = priv;
69 int ret;
70
71 if (gmac->regulator) {
72 ret = regulator_enable(gmac->regulator);
73 if (ret)
74 return ret;
75 }
76
77 /* Set GMAC interface port mode
78 *
79 * The GMAC TX clock lines are configured by setting the clock
80 * rate, which then uses the auto-reparenting feature of the
81 * clock driver, and enabling/disabling the clock.
82 */
83 if (gmac->interface == PHY_INTERFACE_MODE_RGMII) {
84 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
85 clk_prepare_enable(gmac->tx_clk);
86 gmac->clk_enabled = 1;
87 } else {
88 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
89 clk_prepare(gmac->tx_clk);
90 }
91
92 return 0;
93 }
94
sun7i_gmac_exit(struct platform_device * pdev,void * priv)95 static void sun7i_gmac_exit(struct platform_device *pdev, void *priv)
96 {
97 struct sunxi_priv_data *gmac = priv;
98
99 if (gmac->clk_enabled) {
100 clk_disable(gmac->tx_clk);
101 gmac->clk_enabled = 0;
102 }
103 clk_unprepare(gmac->tx_clk);
104
105 if (gmac->regulator)
106 regulator_disable(gmac->regulator);
107 }
108
sun7i_fix_speed(void * priv,unsigned int speed)109 static void sun7i_fix_speed(void *priv, unsigned int speed)
110 {
111 struct sunxi_priv_data *gmac = priv;
112
113 /* only GMII mode requires us to reconfigure the clock lines */
114 if (gmac->interface != PHY_INTERFACE_MODE_GMII)
115 return;
116
117 if (gmac->clk_enabled) {
118 clk_disable(gmac->tx_clk);
119 gmac->clk_enabled = 0;
120 }
121 clk_unprepare(gmac->tx_clk);
122
123 if (speed == 1000) {
124 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
125 clk_prepare_enable(gmac->tx_clk);
126 gmac->clk_enabled = 1;
127 } else {
128 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
129 clk_prepare(gmac->tx_clk);
130 }
131 }
132
133 /* of_data specifying hardware features and callbacks.
134 * hardware features were copied from Allwinner drivers. */
135 const struct stmmac_of_data sun7i_gmac_data = {
136 .has_gmac = 1,
137 .tx_coe = 1,
138 .fix_mac_speed = sun7i_fix_speed,
139 .setup = sun7i_gmac_setup,
140 .init = sun7i_gmac_init,
141 .exit = sun7i_gmac_exit,
142 };
143