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
20struct 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
30static 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
61static 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
75static 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
99static 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
166err_gmac_exit:
167	sun7i_gmac_exit(pdev, plat_dat->bsp_priv);
168err_remove_config_dt:
169	stmmac_remove_config_dt(pdev, plat_dat);
170
171	return ret;
172}
173
174static const struct of_device_id sun7i_dwmac_match[] = {
175	{ .compatible = "allwinner,sun7i-a20-gmac" },
176	{ }
177};
178MODULE_DEVICE_TABLE(of, sun7i_dwmac_match);
179
180static 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};
189module_platform_driver(sun7i_dwmac_driver);
190
191MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
192MODULE_DESCRIPTION("Allwinner sunxi DWMAC specific glue layer");
193MODULE_LICENSE("GPL");
194