1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * dwmac-renesas-gbeth.c - DWMAC Specific Glue layer for Renesas GBETH
4 *
5 * The Rx and Tx clocks are supplied as follows for the GBETH IP.
6 *
7 * Rx / Tx
8 * -------+------------- on / off -------
9 * |
10 * | Rx-180 / Tx-180
11 * +---- not ---- on / off -------
12 *
13 * Copyright (C) 2025 Renesas Electronics Corporation
14 */
15
16 #include <linux/clk.h>
17 #include <linux/device.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/reset.h>
21
22 #include "stmmac_platform.h"
23
24 struct renesas_gbeth {
25 struct plat_stmmacenet_data *plat_dat;
26 struct reset_control *rstc;
27 struct device *dev;
28 };
29
30 static const char *const renesas_gbeth_clks[] = {
31 "tx", "tx-180", "rx", "rx-180",
32 };
33
renesas_gbeth_init(struct platform_device * pdev,void * priv)34 static int renesas_gbeth_init(struct platform_device *pdev, void *priv)
35 {
36 struct plat_stmmacenet_data *plat_dat;
37 struct renesas_gbeth *gbeth = priv;
38 int ret;
39
40 plat_dat = gbeth->plat_dat;
41
42 ret = reset_control_deassert(gbeth->rstc);
43 if (ret) {
44 dev_err(gbeth->dev, "Reset deassert failed\n");
45 return ret;
46 }
47
48 ret = clk_bulk_prepare_enable(plat_dat->num_clks,
49 plat_dat->clks);
50 if (ret)
51 reset_control_assert(gbeth->rstc);
52
53 return ret;
54 }
55
renesas_gbeth_exit(struct platform_device * pdev,void * priv)56 static void renesas_gbeth_exit(struct platform_device *pdev, void *priv)
57 {
58 struct plat_stmmacenet_data *plat_dat;
59 struct renesas_gbeth *gbeth = priv;
60 int ret;
61
62 plat_dat = gbeth->plat_dat;
63
64 clk_bulk_disable_unprepare(plat_dat->num_clks, plat_dat->clks);
65
66 ret = reset_control_assert(gbeth->rstc);
67 if (ret)
68 dev_err(gbeth->dev, "Reset assert failed\n");
69 }
70
renesas_gbeth_probe(struct platform_device * pdev)71 static int renesas_gbeth_probe(struct platform_device *pdev)
72 {
73 struct plat_stmmacenet_data *plat_dat;
74 struct stmmac_resources stmmac_res;
75 struct device *dev = &pdev->dev;
76 struct renesas_gbeth *gbeth;
77 unsigned int i;
78 int err;
79
80 err = stmmac_get_platform_resources(pdev, &stmmac_res);
81 if (err)
82 return dev_err_probe(dev, err,
83 "failed to get resources\n");
84
85 plat_dat = devm_stmmac_probe_config_dt(pdev, stmmac_res.mac);
86 if (IS_ERR(plat_dat))
87 return dev_err_probe(dev, PTR_ERR(plat_dat),
88 "dt configuration failed\n");
89
90 gbeth = devm_kzalloc(dev, sizeof(*gbeth), GFP_KERNEL);
91 if (!gbeth)
92 return -ENOMEM;
93
94 plat_dat->num_clks = ARRAY_SIZE(renesas_gbeth_clks);
95 plat_dat->clks = devm_kcalloc(dev, plat_dat->num_clks,
96 sizeof(*plat_dat->clks), GFP_KERNEL);
97 if (!plat_dat->clks)
98 return -ENOMEM;
99
100 for (i = 0; i < plat_dat->num_clks; i++)
101 plat_dat->clks[i].id = renesas_gbeth_clks[i];
102
103 err = devm_clk_bulk_get(dev, plat_dat->num_clks, plat_dat->clks);
104 if (err < 0)
105 return err;
106
107 plat_dat->clk_tx_i = stmmac_pltfr_find_clk(plat_dat, "tx");
108 if (!plat_dat->clk_tx_i)
109 return dev_err_probe(dev, -EINVAL,
110 "error finding tx clock\n");
111
112 gbeth->rstc = devm_reset_control_get_exclusive(dev, NULL);
113 if (IS_ERR(gbeth->rstc))
114 return PTR_ERR(gbeth->rstc);
115
116 gbeth->dev = dev;
117 gbeth->plat_dat = plat_dat;
118 plat_dat->bsp_priv = gbeth;
119 plat_dat->set_clk_tx_rate = stmmac_set_clk_tx_rate;
120 plat_dat->init = renesas_gbeth_init;
121 plat_dat->exit = renesas_gbeth_exit;
122 plat_dat->flags |= STMMAC_FLAG_HWTSTAMP_CORRECT_LATENCY |
123 STMMAC_FLAG_EN_TX_LPI_CLK_PHY_CAP |
124 STMMAC_FLAG_SPH_DISABLE;
125
126 return devm_stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res);
127 }
128
129 static const struct of_device_id renesas_gbeth_match[] = {
130 { .compatible = "renesas,rzv2h-gbeth", },
131 { /* Sentinel */ }
132 };
133 MODULE_DEVICE_TABLE(of, renesas_gbeth_match);
134
135 static struct platform_driver renesas_gbeth_driver = {
136 .probe = renesas_gbeth_probe,
137 .driver = {
138 .name = "renesas-gbeth",
139 .pm = &stmmac_pltfr_pm_ops,
140 .of_match_table = renesas_gbeth_match,
141 },
142 };
143 module_platform_driver(renesas_gbeth_driver);
144
145 MODULE_AUTHOR("Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>");
146 MODULE_DESCRIPTION("Renesas GBETH DWMAC Specific Glue layer");
147 MODULE_LICENSE("GPL");
148