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, unsigned int mode)
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 = devm_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		return -ENOMEM;
118
119	ret = of_get_phy_mode(dev->of_node, &gmac->interface);
120	if (ret && ret != -ENODEV) {
121		dev_err(dev, "Can't get phy-mode\n");
122		return ret;
123	}
124
125	gmac->tx_clk = devm_clk_get(dev, "allwinner_gmac_tx");
126	if (IS_ERR(gmac->tx_clk)) {
127		dev_err(dev, "could not get tx clock\n");
128		return PTR_ERR(gmac->tx_clk);
129	}
130
131	/* Optional regulator for PHY */
132	gmac->regulator = devm_regulator_get_optional(dev, "phy");
133	if (IS_ERR(gmac->regulator)) {
134		if (PTR_ERR(gmac->regulator) == -EPROBE_DEFER)
135			return -EPROBE_DEFER;
136		dev_info(dev, "no regulator found\n");
137		gmac->regulator = NULL;
138	}
139
140	/* platform data specifying hardware features and callbacks.
141	 * hardware features were copied from Allwinner drivers. */
142	plat_dat->tx_coe = 1;
143	plat_dat->has_gmac = true;
144	plat_dat->bsp_priv = gmac;
145	plat_dat->init = sun7i_gmac_init;
146	plat_dat->exit = sun7i_gmac_exit;
147	plat_dat->fix_mac_speed = sun7i_fix_speed;
148	plat_dat->tx_fifo_size = 4096;
149	plat_dat->rx_fifo_size = 16384;
150
151	ret = sun7i_gmac_init(pdev, plat_dat->bsp_priv);
152	if (ret)
153		return ret;
154
155	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
156	if (ret)
157		goto err_gmac_exit;
158
159	return 0;
160
161err_gmac_exit:
162	sun7i_gmac_exit(pdev, plat_dat->bsp_priv);
163
164	return ret;
165}
166
167static const struct of_device_id sun7i_dwmac_match[] = {
168	{ .compatible = "allwinner,sun7i-a20-gmac" },
169	{ }
170};
171MODULE_DEVICE_TABLE(of, sun7i_dwmac_match);
172
173static struct platform_driver sun7i_dwmac_driver = {
174	.probe  = sun7i_gmac_probe,
175	.remove_new = stmmac_pltfr_remove,
176	.driver = {
177		.name           = "sun7i-dwmac",
178		.pm		= &stmmac_pltfr_pm_ops,
179		.of_match_table = sun7i_dwmac_match,
180	},
181};
182module_platform_driver(sun7i_dwmac_driver);
183
184MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
185MODULE_DESCRIPTION("Allwinner sunxi DWMAC specific glue layer");
186MODULE_LICENSE("GPL");
187