1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * StarFive DWMAC platform driver
4  *
5  * Copyright (C) 2021 Emil Renner Berthing <kernel@esmil.dk>
6  * Copyright (C) 2022 StarFive Technology Co., Ltd.
7  *
8  */
9 
10 #include <linux/mod_devicetable.h>
11 #include <linux/platform_device.h>
12 #include <linux/property.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/regmap.h>
15 
16 #include "stmmac_platform.h"
17 
18 #define STARFIVE_DWMAC_PHY_INFT_RGMII		0x1
19 #define STARFIVE_DWMAC_PHY_INFT_RMII		0x4
20 #define STARFIVE_DWMAC_PHY_INFT_FIELD		0x7U
21 
22 #define JH7100_SYSMAIN_REGISTER49_DLYCHAIN	0xc8
23 
24 struct starfive_dwmac_data {
25 	unsigned int gtxclk_dlychain;
26 };
27 
28 struct starfive_dwmac {
29 	struct device *dev;
30 	struct clk *clk_tx;
31 	const struct starfive_dwmac_data *data;
32 };
33 
34 static void starfive_dwmac_fix_mac_speed(void *priv, unsigned int speed, unsigned int mode)
35 {
36 	struct starfive_dwmac *dwmac = priv;
37 	unsigned long rate;
38 	int err;
39 
40 	rate = clk_get_rate(dwmac->clk_tx);
41 
42 	switch (speed) {
43 	case SPEED_1000:
44 		rate = 125000000;
45 		break;
46 	case SPEED_100:
47 		rate = 25000000;
48 		break;
49 	case SPEED_10:
50 		rate = 2500000;
51 		break;
52 	default:
53 		dev_err(dwmac->dev, "invalid speed %u\n", speed);
54 		break;
55 	}
56 
57 	err = clk_set_rate(dwmac->clk_tx, rate);
58 	if (err)
59 		dev_err(dwmac->dev, "failed to set tx rate %lu\n", rate);
60 }
61 
62 static int starfive_dwmac_set_mode(struct plat_stmmacenet_data *plat_dat)
63 {
64 	struct starfive_dwmac *dwmac = plat_dat->bsp_priv;
65 	struct regmap *regmap;
66 	unsigned int args[2];
67 	unsigned int mode;
68 	int err;
69 
70 	switch (plat_dat->mac_interface) {
71 	case PHY_INTERFACE_MODE_RMII:
72 		mode = STARFIVE_DWMAC_PHY_INFT_RMII;
73 		break;
74 
75 	case PHY_INTERFACE_MODE_RGMII:
76 	case PHY_INTERFACE_MODE_RGMII_ID:
77 	case PHY_INTERFACE_MODE_RGMII_RXID:
78 	case PHY_INTERFACE_MODE_RGMII_TXID:
79 		mode = STARFIVE_DWMAC_PHY_INFT_RGMII;
80 		break;
81 
82 	default:
83 		dev_err(dwmac->dev, "unsupported interface %d\n",
84 			plat_dat->mac_interface);
85 		return -EINVAL;
86 	}
87 
88 	regmap = syscon_regmap_lookup_by_phandle_args(dwmac->dev->of_node,
89 						      "starfive,syscon",
90 						      2, args);
91 	if (IS_ERR(regmap))
92 		return dev_err_probe(dwmac->dev, PTR_ERR(regmap), "getting the regmap failed\n");
93 
94 	/* args[0]:offset  args[1]: shift */
95 	err = regmap_update_bits(regmap, args[0],
96 				 STARFIVE_DWMAC_PHY_INFT_FIELD << args[1],
97 				 mode << args[1]);
98 	if (err)
99 		return dev_err_probe(dwmac->dev, err, "error setting phy mode\n");
100 
101 	if (dwmac->data) {
102 		err = regmap_write(regmap, JH7100_SYSMAIN_REGISTER49_DLYCHAIN,
103 				   dwmac->data->gtxclk_dlychain);
104 		if (err)
105 			return dev_err_probe(dwmac->dev, err,
106 					     "error selecting gtxclk delay chain\n");
107 	}
108 
109 	return 0;
110 }
111 
112 static int starfive_dwmac_probe(struct platform_device *pdev)
113 {
114 	struct plat_stmmacenet_data *plat_dat;
115 	struct stmmac_resources stmmac_res;
116 	struct starfive_dwmac *dwmac;
117 	struct clk *clk_gtx;
118 	int err;
119 
120 	err = stmmac_get_platform_resources(pdev, &stmmac_res);
121 	if (err)
122 		return dev_err_probe(&pdev->dev, err,
123 				     "failed to get resources\n");
124 
125 	plat_dat = stmmac_probe_config_dt(pdev, stmmac_res.mac);
126 	if (IS_ERR(plat_dat))
127 		return dev_err_probe(&pdev->dev, PTR_ERR(plat_dat),
128 				     "dt configuration failed\n");
129 
130 	dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
131 	if (!dwmac)
132 		return -ENOMEM;
133 
134 	dwmac->data = device_get_match_data(&pdev->dev);
135 
136 	dwmac->clk_tx = devm_clk_get_enabled(&pdev->dev, "tx");
137 	if (IS_ERR(dwmac->clk_tx))
138 		return dev_err_probe(&pdev->dev, PTR_ERR(dwmac->clk_tx),
139 				     "error getting tx clock\n");
140 
141 	clk_gtx = devm_clk_get_enabled(&pdev->dev, "gtx");
142 	if (IS_ERR(clk_gtx))
143 		return dev_err_probe(&pdev->dev, PTR_ERR(clk_gtx),
144 				     "error getting gtx clock\n");
145 
146 	/* Generally, the rgmii_tx clock is provided by the internal clock,
147 	 * which needs to match the corresponding clock frequency according
148 	 * to different speeds. If the rgmii_tx clock is provided by the
149 	 * external rgmii_rxin, there is no need to configure the clock
150 	 * internally, because rgmii_rxin will be adaptively adjusted.
151 	 */
152 	if (!device_property_read_bool(&pdev->dev, "starfive,tx-use-rgmii-clk"))
153 		plat_dat->fix_mac_speed = starfive_dwmac_fix_mac_speed;
154 
155 	dwmac->dev = &pdev->dev;
156 	plat_dat->bsp_priv = dwmac;
157 	plat_dat->dma_cfg->dche = true;
158 
159 	err = starfive_dwmac_set_mode(plat_dat);
160 	if (err)
161 		return err;
162 
163 	err = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
164 	if (err) {
165 		stmmac_remove_config_dt(pdev, plat_dat);
166 		return err;
167 	}
168 
169 	return 0;
170 }
171 
172 static const struct starfive_dwmac_data jh7100_data = {
173 	.gtxclk_dlychain = 4,
174 };
175 
176 static const struct of_device_id starfive_dwmac_match[] = {
177 	{ .compatible = "starfive,jh7100-dwmac", .data = &jh7100_data },
178 	{ .compatible = "starfive,jh7110-dwmac" },
179 	{ /* sentinel */ }
180 };
181 MODULE_DEVICE_TABLE(of, starfive_dwmac_match);
182 
183 static struct platform_driver starfive_dwmac_driver = {
184 	.probe  = starfive_dwmac_probe,
185 	.remove_new = stmmac_pltfr_remove,
186 	.driver = {
187 		.name = "starfive-dwmac",
188 		.pm = &stmmac_pltfr_pm_ops,
189 		.of_match_table = starfive_dwmac_match,
190 	},
191 };
192 module_platform_driver(starfive_dwmac_driver);
193 
194 MODULE_LICENSE("GPL");
195 MODULE_DESCRIPTION("StarFive DWMAC platform driver");
196 MODULE_AUTHOR("Emil Renner Berthing <kernel@esmil.dk>");
197 MODULE_AUTHOR("Samin Guo <samin.guo@starfivetech.com>");
198