[PATCH net-next v2 3/3] net: stmmac: Add DWMAC glue layer for Renesas GBETH
From: Prabhakar
Date: Sat Mar 08 2025 - 15:10:53 EST
From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Add the DWMAC glue layer for the GBETH IP found in the Renesas RZ/V2H(P)
SoC.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
---
v1->v2
- Dropped __initconst for renesas_gbeth_clks array
- Added clks_config callback
- Dropped STMMAC_FLAG_RX_CLK_RUNS_IN_LPI flag as this needs
investigation.
---
drivers/net/ethernet/stmicro/stmmac/Kconfig | 11 ++
drivers/net/ethernet/stmicro/stmmac/Makefile | 1 +
.../stmicro/stmmac/dwmac-renesas-gbeth.c | 165 ++++++++++++++++++
3 files changed, 177 insertions(+)
create mode 100644 drivers/net/ethernet/stmicro/stmmac/dwmac-renesas-gbeth.c
diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
index 3c820ef56775..2c99b23f0faa 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
+++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
@@ -131,6 +131,17 @@ config DWMAC_QCOM_ETHQOS
This selects the Qualcomm ETHQOS glue layer support for the
stmmac device driver.
+config DWMAC_RENESAS_GBETH
+ tristate "Renesas RZ/V2H(P) GBETH support"
+ default ARCH_RENESAS
+ depends on OF && (ARCH_RENESAS || COMPILE_TEST)
+ help
+ Support for Gigabit Ethernet Interface (GBETH) on Renesas
+ RZ/V2H(P) SoCs.
+
+ This selects the Renesas RZ/V2H(P) Soc specific glue layer support
+ for the stmmac device driver.
+
config DWMAC_ROCKCHIP
tristate "Rockchip dwmac support"
default ARCH_ROCKCHIP
diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
index 594883fb4164..91050215511b 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Makefile
+++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_DWMAC_LPC18XX) += dwmac-lpc18xx.o
obj-$(CONFIG_DWMAC_MEDIATEK) += dwmac-mediatek.o
obj-$(CONFIG_DWMAC_MESON) += dwmac-meson.o dwmac-meson8b.o
obj-$(CONFIG_DWMAC_QCOM_ETHQOS) += dwmac-qcom-ethqos.o
+obj-$(CONFIG_DWMAC_RENESAS_GBETH) += dwmac-renesas-gbeth.o
obj-$(CONFIG_DWMAC_ROCKCHIP) += dwmac-rk.o
obj-$(CONFIG_DWMAC_RZN1) += dwmac-rzn1.o
obj-$(CONFIG_DWMAC_S32) += dwmac-s32.o
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-renesas-gbeth.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-renesas-gbeth.c
new file mode 100644
index 000000000000..7527387f30a0
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-renesas-gbeth.c
@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * dwmac-renesas-gbeth.c - DWMAC Specific Glue layer for Renesas GBETH
+ *
+ * The Rx and Tx clocks are supplied as follows for the GBETH IP.
+ *
+ * Rx / Tx
+ * -------+------------- on / off -------
+ * |
+ * | Rx-180 / Tx-180
+ * +---- not ---- on / off -------
+ *
+ * Copyright (C) 2025 Renesas Electronics Corporation
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+#include "dwmac4.h"
+#include "stmmac_platform.h"
+
+struct renesas_gbeth {
+ struct device *dev;
+ void __iomem *regs;
+ unsigned int num_clks;
+ struct clk *clk_tx_i;
+ struct clk_bulk_data *clks;
+ struct reset_control *rstc;
+};
+
+static const char *const renesas_gbeth_clks[] = {
+ "rx", "rx-180", "tx-180",
+};
+
+static int renesas_gbeth_clks_config(void *priv, bool enabled)
+{
+ struct renesas_gbeth *gbeth = priv;
+ int ret;
+
+ if (enabled) {
+ ret = reset_control_deassert(gbeth->rstc);
+ if (ret) {
+ dev_err(gbeth->dev, "Reset deassert failed\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(gbeth->clk_tx_i);
+ if (ret) {
+ dev_err(gbeth->dev, "Tx clock enable failed\n");
+ reset_control_assert(gbeth->rstc);
+ return ret;
+ }
+
+ ret = clk_bulk_prepare_enable(gbeth->num_clks, gbeth->clks);
+ if (ret)
+ clk_disable_unprepare(gbeth->clk_tx_i);
+ } else {
+ clk_bulk_disable_unprepare(gbeth->num_clks, gbeth->clks);
+ clk_disable_unprepare(gbeth->clk_tx_i);
+ ret = reset_control_assert(gbeth->rstc);
+ if (ret)
+ dev_err(gbeth->dev, "Reset assert failed\n");
+ }
+
+ return ret;
+}
+
+static int renesas_gbeth_probe(struct platform_device *pdev)
+{
+ struct plat_stmmacenet_data *plat_dat;
+ struct stmmac_resources stmmac_res;
+ struct device *dev = &pdev->dev;
+ struct renesas_gbeth *gbeth;
+ unsigned int i;
+ int err;
+
+ err = stmmac_get_platform_resources(pdev, &stmmac_res);
+ if (err)
+ return dev_err_probe(dev, err,
+ "failed to get resources\n");
+
+ plat_dat = devm_stmmac_probe_config_dt(pdev, stmmac_res.mac);
+ if (IS_ERR(plat_dat))
+ return dev_err_probe(dev, PTR_ERR(plat_dat),
+ "dt configuration failed\n");
+
+ gbeth = devm_kzalloc(dev, sizeof(*gbeth), GFP_KERNEL);
+ if (!gbeth)
+ return -ENOMEM;
+
+ plat_dat->clk_tx_i = devm_clk_get(dev, "tx");
+ if (IS_ERR(plat_dat->clk_tx_i))
+ return dev_err_probe(dev, PTR_ERR(plat_dat->clk_tx_i),
+ "error getting tx clock\n");
+
+ gbeth->clk_tx_i = plat_dat->clk_tx_i;
+ gbeth->num_clks = ARRAY_SIZE(renesas_gbeth_clks);
+ gbeth->clks = devm_kcalloc(dev, gbeth->num_clks,
+ sizeof(*gbeth->clks), GFP_KERNEL);
+ if (!gbeth->clks)
+ return -ENOMEM;
+
+ for (i = 0; i < gbeth->num_clks; i++)
+ gbeth->clks[i].id = renesas_gbeth_clks[i];
+
+ err = devm_clk_bulk_get(dev, gbeth->num_clks, gbeth->clks);
+ if (err < 0)
+ return err;
+
+ gbeth->rstc = devm_reset_control_get_exclusive(dev, NULL);
+ if (IS_ERR(gbeth->rstc))
+ return PTR_ERR(gbeth->rstc);
+
+ gbeth->dev = dev;
+ gbeth->regs = stmmac_res.addr;
+ plat_dat->bsp_priv = gbeth;
+ plat_dat->set_clk_tx_rate = stmmac_set_clk_tx_rate;
+ plat_dat->clks_config = renesas_gbeth_clks_config;
+ plat_dat->flags |= STMMAC_FLAG_HWTSTAMP_CORRECT_LATENCY |
+ STMMAC_FLAG_EN_TX_LPI_CLOCKGATING |
+ STMMAC_FLAG_SPH_DISABLE;
+
+ err = renesas_gbeth_clks_config(gbeth, true);
+ if (err)
+ return err;
+
+ err = stmmac_dvr_probe(dev, plat_dat, &stmmac_res);
+ if (err) {
+ renesas_gbeth_clks_config(gbeth, false);
+ return err;
+ }
+
+ return 0;
+}
+
+static void renesas_gbeth_remove(struct platform_device *pdev)
+{
+ stmmac_dvr_remove(&pdev->dev);
+
+ renesas_gbeth_clks_config(get_stmmac_bsp_priv(&pdev->dev), false);
+}
+
+static const struct of_device_id renesas_gbeth_match[] = {
+ { .compatible = "renesas,rzv2h-gbeth", },
+ { /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, renesas_gbeth_match);
+
+static struct platform_driver renesas_gbeth_driver = {
+ .probe = renesas_gbeth_probe,
+ .remove = renesas_gbeth_remove,
+ .driver = {
+ .name = "renesas-gbeth",
+ .pm = &stmmac_pltfr_pm_ops,
+ .of_match_table = renesas_gbeth_match,
+ },
+};
+module_platform_driver(renesas_gbeth_driver);
+
+MODULE_AUTHOR("Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Renesas GBETH DWMAC Specific Glue layer");
+MODULE_LICENSE("GPL");
--
2.43.0