dwmac-renesas-gbeth.c

  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/of.h>
 20#include <linux/pcs-rzn1-miic.h>
 21#include <linux/platform_device.h>
 22#include <linux/reset.h>
 23#include <linux/types.h>
 24
 25#include "stmmac_platform.h"
 26
 27/**
 28 * struct renesas_gbeth_of_data - OF data for Renesas GBETH
 29 *
 30 * @clks: Array of clock names
 31 * @num_clks: Number of clocks
 32 * @stmmac_flags: Flags for the stmmac driver
 33 * @handle_reset: Flag to indicate if reset control is
 34 *                handled by the glue driver or core driver.
 35 * @set_clk_tx_rate: Flag to indicate if Tx clock is fixed or
 36 *                   set_clk_tx_rate is needed.
 37 * @has_pcs: Flag to indicate if the MAC has a PCS
 38 */
 39struct renesas_gbeth_of_data {
 40	const char * const *clks;
 41	u8 num_clks;
 42	u32 stmmac_flags;
 43	bool handle_reset;
 44	bool set_clk_tx_rate;
 45	bool has_pcs;
 46};
 47
 48struct renesas_gbeth {
 49	const struct renesas_gbeth_of_data *of_data;
 50	struct plat_stmmacenet_data *plat_dat;
 51	struct reset_control *rstc;
 52	struct device *dev;
 53};
 54
 55static const char *const renesas_gbeth_clks[] = {
 56	"tx", "tx-180", "rx", "rx-180",
 57};
 58
 59static const char *const renesas_gmac_clks[] = {
 60	"tx",
 61};
 62
 63static int renesas_gmac_pcs_init(struct stmmac_priv *priv)
 64{
 65	struct device_node *np = priv->device->of_node;
 66	struct device_node *pcs_node;
 67	struct phylink_pcs *pcs;
 68
 69	pcs_node = of_parse_phandle(np, "pcs-handle", 0);
 70	if (pcs_node) {
 71		pcs = miic_create(priv->device, pcs_node);
 72		of_node_put(pcs_node);
 73		if (IS_ERR(pcs))
 74			return PTR_ERR(pcs);
 75
 76		priv->hw->phylink_pcs = pcs;
 77	}
 78
 79	return 0;
 80}
 81
 82static void renesas_gmac_pcs_exit(struct stmmac_priv *priv)
 83{
 84	if (priv->hw->phylink_pcs)
 85		miic_destroy(priv->hw->phylink_pcs);
 86}
 87
 88static struct phylink_pcs *renesas_gmac_select_pcs(struct stmmac_priv *priv,
 89						   phy_interface_t interface)
 90{
 91	return priv->hw->phylink_pcs;
 92}
 93
 94static int renesas_gbeth_init(struct device *dev, void *priv)
 95{
 96	struct plat_stmmacenet_data *plat_dat;
 97	struct renesas_gbeth *gbeth = priv;
 98	int ret;
 99
100	plat_dat = gbeth->plat_dat;
101
102	ret = reset_control_deassert(gbeth->rstc);
103	if (ret) {
104		dev_err(gbeth->dev, "Reset deassert failed\n");
105		return ret;
106	}
107
108	ret = clk_bulk_prepare_enable(plat_dat->num_clks,
109				      plat_dat->clks);
110	if (ret)
111		reset_control_assert(gbeth->rstc);
112
113	return ret;
114}
115
116static void renesas_gbeth_exit(struct device *dev, void *priv)
117{
118	struct plat_stmmacenet_data *plat_dat;
119	struct renesas_gbeth *gbeth = priv;
120	int ret;
121
122	plat_dat = gbeth->plat_dat;
123
124	clk_bulk_disable_unprepare(plat_dat->num_clks, plat_dat->clks);
125
126	ret = reset_control_assert(gbeth->rstc);
127	if (ret)
128		dev_err(gbeth->dev, "Reset assert failed\n");
129}
130
131static int renesas_gbeth_probe(struct platform_device *pdev)
132{
133	const struct renesas_gbeth_of_data *of_data;
134	struct plat_stmmacenet_data *plat_dat;
135	struct stmmac_resources stmmac_res;
136	struct device *dev = &pdev->dev;
137	struct renesas_gbeth *gbeth;
138	unsigned int i;
139	int err;
140
141	err = stmmac_get_platform_resources(pdev, &stmmac_res);
142	if (err)
143		return dev_err_probe(dev, err,
144				     "failed to get resources\n");
145
146	plat_dat = devm_stmmac_probe_config_dt(pdev, stmmac_res.mac);
147	if (IS_ERR(plat_dat))
148		return dev_err_probe(dev, PTR_ERR(plat_dat),
149				     "dt configuration failed\n");
150
151	gbeth = devm_kzalloc(dev, sizeof(*gbeth), GFP_KERNEL);
152	if (!gbeth)
153		return -ENOMEM;
154
155	of_data = of_device_get_match_data(&pdev->dev);
156	gbeth->of_data = of_data;
157
158	plat_dat->num_clks = of_data->num_clks;
159	plat_dat->clks = devm_kcalloc(dev, plat_dat->num_clks,
160				      sizeof(*plat_dat->clks), GFP_KERNEL);
161	if (!plat_dat->clks)
162		return -ENOMEM;
163
164	for (i = 0; i < plat_dat->num_clks; i++)
165		plat_dat->clks[i].id = of_data->clks[i];
166
167	err = devm_clk_bulk_get(dev, plat_dat->num_clks, plat_dat->clks);
168	if (err < 0)
169		return err;
170
171	plat_dat->clk_tx_i = stmmac_pltfr_find_clk(plat_dat, "tx");
172	if (!plat_dat->clk_tx_i)
173		return dev_err_probe(dev, -EINVAL,
174				     "error finding tx clock\n");
175
176	if (of_data->handle_reset) {
177		gbeth->rstc = devm_reset_control_get_exclusive(dev, NULL);
178		if (IS_ERR(gbeth->rstc))
179			return PTR_ERR(gbeth->rstc);
180	}
181
182	gbeth->dev = dev;
183	gbeth->plat_dat = plat_dat;
184	plat_dat->bsp_priv = gbeth;
185	if (of_data->set_clk_tx_rate)
186		plat_dat->set_clk_tx_rate = stmmac_set_clk_tx_rate;
187	plat_dat->init = renesas_gbeth_init;
188	plat_dat->exit = renesas_gbeth_exit;
189	plat_dat->flags |= STMMAC_FLAG_EN_TX_LPI_CLK_PHY_CAP |
190			   gbeth->of_data->stmmac_flags;
191	if (of_data->has_pcs) {
192		plat_dat->pcs_init = renesas_gmac_pcs_init;
193		plat_dat->pcs_exit = renesas_gmac_pcs_exit;
194		plat_dat->select_pcs = renesas_gmac_select_pcs;
195	}
196
197	return devm_stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res);
198}
199
200static const struct renesas_gbeth_of_data renesas_gbeth_of_data = {
201	.clks = renesas_gbeth_clks,
202	.num_clks = ARRAY_SIZE(renesas_gbeth_clks),
203	.handle_reset = true,
204	.set_clk_tx_rate = true,
205	.stmmac_flags = STMMAC_FLAG_HWTSTAMP_CORRECT_LATENCY |
206			STMMAC_FLAG_SPH_DISABLE,
207};
208
209static const struct renesas_gbeth_of_data renesas_gmac_of_data = {
210	.clks = renesas_gmac_clks,
211	.num_clks = ARRAY_SIZE(renesas_gmac_clks),
212	.stmmac_flags = STMMAC_FLAG_HWTSTAMP_CORRECT_LATENCY,
213	.has_pcs = true,
214};
215
216static const struct of_device_id renesas_gbeth_match[] = {
217	{ .compatible = "renesas,r9a09g077-gbeth", .data = &renesas_gmac_of_data },
218	{ .compatible = "renesas,rzv2h-gbeth", .data = &renesas_gbeth_of_data },
219	{ /* Sentinel */ }
220};
221MODULE_DEVICE_TABLE(of, renesas_gbeth_match);
222
223static struct platform_driver renesas_gbeth_driver = {
224	.probe  = renesas_gbeth_probe,
225	.driver = {
226		.name		= "renesas-gbeth",
227		.pm		= &stmmac_pltfr_pm_ops,
228		.of_match_table	= renesas_gbeth_match,
229	},
230};
231module_platform_driver(renesas_gbeth_driver);
232
233MODULE_AUTHOR("Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>");
234MODULE_DESCRIPTION("Renesas GBETH DWMAC Specific Glue layer");
235MODULE_LICENSE("GPL");