net: stmmac: dwmac-nuvoton: Add dwmac glue for Nuvoton MA35 family

Add support for Gigabit Ethernet on Nuvoton MA35 series using dwmac driver.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Joey Lu <a0987203069@gmail.com>
Link: https://patch.msgid.link/20260323101756.81849-4-a0987203069@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
index d3a6ab7383fc1e1b2e4b12c670b12a8ad1606e6c..c2cb530fd0a2f49821147a308218eb7327debd75 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
+++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
@@ -132,6 +132,18 @@ config DWMAC_MESON
          the stmmac device driver. This driver is used for Meson6,
          Meson8, Meson8b and GXBB SoCs.
 
+config DWMAC_NUVOTON
+       tristate "Nuvoton MA35 dwmac support"
+       default ARCH_MA35
+       depends on OF && (ARCH_MA35 || COMPILE_TEST)
+       select MFD_SYSCON
+       help
+         Support for Ethernet controller on Nuvoton MA35 series SoC.
+
+         This selects the Nuvoton MA35 series SoC glue layer support
+         for the stmmac device driver. The nuvoton-dwmac driver is
+         used for MA35 series SoCs.
+
 config DWMAC_QCOM_ETHQOS
        tristate "Qualcomm ETHQOS support"
        default ARCH_QCOM

diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
index 945c5354ecedc6fc4737852283d0cc77b110b368..a1cea2f57252e69afcc6b9f0011c26f6966b638e 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/Makefile
+++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_DWMAC_IPQ806X)   += dwmac-ipq806x.o
 obj-$(CONFIG_DWMAC_LPC18XX)    += dwmac-lpc18xx.o
 obj-$(CONFIG_DWMAC_MEDIATEK)   += dwmac-mediatek.o
 obj-$(CONFIG_DWMAC_MESON)      += dwmac-meson.o dwmac-meson8b.o
+obj-$(CONFIG_DWMAC_NUVOTON)    += dwmac-nuvoton.o
 obj-$(CONFIG_DWMAC_QCOM_ETHQOS)        += dwmac-qcom-ethqos.o
 obj-$(CONFIG_DWMAC_RENESAS_GBETH) += dwmac-renesas-gbeth.o
 obj-$(CONFIG_DWMAC_ROCKCHIP)   += dwmac-rk.o

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-nuvoton.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-nuvoton.c
new file mode 100644 (file)
index 0000000..e2240b6
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-nuvoton.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Nuvoton DWMAC specific glue layer
+ *
+ * Copyright (C) 2025 Nuvoton Technology Corp.
+ *
+ * Author: Joey Lu <a0987203069@gmail.com>
+ */
+
+#include <linux/mfd/syscon.h>
+#include <linux/mod_devicetable.h>
+#include <linux/of.h>
+#include <linux/of_net.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/stmmac.h>
+
+#include "stmmac_platform.h"
+
+#define NVT_REG_SYS_GMAC0MISCR  0x108
+#define NVT_REG_SYS_GMAC1MISCR  0x10C
+
+#define NVT_MISCR_RMII          BIT(0)
+
+/* Two thousand picoseconds are evenly mapped to a 4-bit field,
+ * resulting in each step being 2000/15 picoseconds.
+ */
+#define NVT_PATH_DELAY_STEP     134
+#define NVT_TX_DELAY_MASK       GENMASK(19, 16)
+#define NVT_RX_DELAY_MASK       GENMASK(23, 20)
+
+struct nvt_priv_data {
+       struct device *dev;
+       struct regmap *regmap;
+       u32 macid;
+};
+
+static int nvt_gmac_get_delay(struct device *dev, const char *property)
+{
+       u32 arg;
+
+       if (of_property_read_u32(dev->of_node, property, &arg))
+               return 0;
+
+       if (arg > 2000)
+               return -EINVAL;
+
+       if (arg == 2000)
+               return 15;
+
+       return arg / NVT_PATH_DELAY_STEP;
+}
+
+static int nvt_set_phy_intf_sel(void *bsp_priv, u8 phy_intf_sel)
+{
+       struct nvt_priv_data *priv = bsp_priv;
+       u32 reg, val;
+       int ret;
+
+       if (phy_intf_sel == PHY_INTF_SEL_RGMII) {
+               ret = nvt_gmac_get_delay(priv->dev, "rx-internal-delay-ps");
+               if (ret < 0)
+                       return ret;
+               val = FIELD_PREP(NVT_RX_DELAY_MASK, ret);
+
+               ret = nvt_gmac_get_delay(priv->dev, "tx-internal-delay-ps");
+               if (ret < 0)
+                       return ret;
+               val |= FIELD_PREP(NVT_TX_DELAY_MASK, ret);
+       } else if (phy_intf_sel == PHY_INTF_SEL_RMII) {
+               val = NVT_MISCR_RMII;
+       } else {
+               return -EINVAL;
+       }
+
+       reg = (priv->macid == 0) ? NVT_REG_SYS_GMAC0MISCR : NVT_REG_SYS_GMAC1MISCR;
+       regmap_update_bits(priv->regmap, reg,
+                          NVT_RX_DELAY_MASK | NVT_TX_DELAY_MASK | NVT_MISCR_RMII, val);
+
+       return 0;
+}
+
+static int nvt_gmac_probe(struct platform_device *pdev)
+{
+       struct plat_stmmacenet_data *plat_dat;
+       struct stmmac_resources stmmac_res;
+       struct device *dev = &pdev->dev;
+       struct nvt_priv_data *priv;
+       int ret;
+
+       ret = stmmac_get_platform_resources(pdev, &stmmac_res);
+       if (ret)
+               return dev_err_probe(dev, ret, "Failed to get platform 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), "Failed to get platform data\n");
+
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return dev_err_probe(dev, -ENOMEM, "Failed to allocate private data\n");
+
+       priv->regmap = syscon_regmap_lookup_by_phandle_args(dev->of_node, "nuvoton,sys",
+                                                           1, &priv->macid);
+       if (IS_ERR(priv->regmap))
+               return dev_err_probe(dev, PTR_ERR(priv->regmap), "Failed to get sys register\n");
+
+       if (priv->macid > 1)
+               return dev_err_probe(dev, -EINVAL, "Invalid sys arguments\n");
+
+       plat_dat->bsp_priv = priv;
+       plat_dat->set_phy_intf_sel = nvt_set_phy_intf_sel;
+
+       return stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res);
+}
+
+static const struct of_device_id nvt_dwmac_match[] = {
+       { .compatible = "nuvoton,ma35d1-dwmac"},
+       { }
+};
+MODULE_DEVICE_TABLE(of, nvt_dwmac_match);
+
+static struct platform_driver nvt_dwmac_driver = {
+       .probe  = nvt_gmac_probe,
+       .remove = stmmac_pltfr_remove,
+       .driver = {
+               .name           = "nuvoton-dwmac",
+               .pm             = &stmmac_pltfr_pm_ops,
+               .of_match_table = nvt_dwmac_match,
+       },
+};
+module_platform_driver(nvt_dwmac_driver);
+
+MODULE_AUTHOR("Joey Lu <a0987203069@gmail.com>");
+MODULE_DESCRIPTION("Nuvoton DWMAC specific glue layer");
+MODULE_LICENSE("GPL");