net: stmmac: Add glue layer for StarFive JH71x0 SoCs

This adds a glue layer for the Synopsys DesignWare MAC IP core on the
StarFive JH71x0 SoCs.

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>

diff --git a/MAINTAINERS b/MAINTAINERS
index 18d4b97b56887bd8b282bc9d3869ac397301a529..41f04811fb1443b7bec2053bab504ba25f4c272e 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19643,6 +19643,12 @@ M:     Emil Renner Berthing <kernel@esmil.dk>
 S:     Maintained
 F:     arch/riscv/boot/dts/starfive/
 
+STARFIVE DWMAC GLUE LAYER
+M:     Emil Renner Berthing <kernel@esmil.dk>
+S:     Maintained
+F:     Documentation/devicetree/bindings/net/dwmac-starfive.yaml
+F:     drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
+
 STARFIVE JH7100 CLOCK DRIVERS
 M:     Emil Renner Berthing <kernel@esmil.dk>
 S:     Maintained

diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
index 31ff35174034297ab68cc6eeae6b9d063812f1f4..afe5bb88962b3b341d779910d14b9b9fae454d7f 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
+++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
@@ -165,6 +165,18 @@ config DWMAC_SOCFPGA
          for the stmmac device driver. This driver is used for
          arria5 and cyclone5 FPGA SoCs.
 
+config DWMAC_STARFIVE
+       tristate "StarFive DWMAC support"
+       default m if SOC_STARFIVE
+       depends on SOC_STARFIVE || COMPILE_TEST
+       select MFD_SYSCON
+       help
+         Support for ethernet controller on StarFive SOCs.
+
+         This selects StarFive SoC glue layer support for the stmmac device
+         driver. This driver is used for the JH71x0 series GMAC ethernet
+         controller.
+
 config DWMAC_STI
        tristate "STi GMAC support"
        default ARCH_STI

diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
index d4e12e9ace4ffe3ab45267fc610148e877a9a9c2..09e3c141c2a11e667deb5fa763c68a2709978ffe 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/Makefile
+++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_DWMAC_OXNAS)     += dwmac-oxnas.o
 obj-$(CONFIG_DWMAC_QCOM_ETHQOS)        += dwmac-qcom-ethqos.o
 obj-$(CONFIG_DWMAC_ROCKCHIP)   += dwmac-rk.o
 obj-$(CONFIG_DWMAC_SOCFPGA)    += dwmac-altr-socfpga.o
+obj-$(CONFIG_DWMAC_STARFIVE)   += dwmac-starfive.o
 obj-$(CONFIG_DWMAC_STI)                += dwmac-sti.o
 obj-$(CONFIG_DWMAC_STM32)      += dwmac-stm32.o
 obj-$(CONFIG_DWMAC_SUNXI)      += dwmac-sunxi.o

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
new file mode 100644 (file)
index 0000000..4e1a339
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * dwmac-starfive.c - DWMAC glue layer for StarFive SoCs
+ *
+ * Copyright (C) 2021 Emil Renner Berthing <kernel@esmil.dk>
+ */
+
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include "stmmac.h"
+#include "stmmac_platform.h"
+
+#define JH7100_SYSMAIN_REGISTER28 0x70
+/* The value below is not a typo, just really bad naming by StarFive ¯\_(ツ)_/¯ */
+#define JH7100_SYSMAIN_REGISTER49 0xc8
+
+struct dwmac_starfive {
+       struct device *dev;
+       struct clk *gtxc;
+};
+
+static int dwmac_starfive_jh7100_syscon_init(struct device *dev)
+{
+       struct device_node *np = dev->of_node;
+       struct regmap *sysmain;
+       u32 gtxclk_dlychain;
+       int ret;
+
+       sysmain = syscon_regmap_lookup_by_phandle(np, "starfive,syscon");
+       if (IS_ERR(sysmain))
+               return dev_err_probe(dev, PTR_ERR(sysmain),
+                                    "error getting sysmain registers\n");
+
+       /* Choose RGMII interface to the phy.
+        * TODO: support other interfaces once we know the meaning of other
+        * values in the register
+        */
+       ret = regmap_update_bits(sysmain, JH7100_SYSMAIN_REGISTER28, 0x7, 1);
+       if (ret)
+               return dev_err_probe(dev, ret, "error selecting gmac interface\n");
+
+       if (!of_property_read_u32(np, "starfive,gtxclk-dlychain", &gtxclk_dlychain)) {
+               ret = regmap_write(sysmain, JH7100_SYSMAIN_REGISTER49, gtxclk_dlychain);
+               if (ret)
+                       return dev_err_probe(dev, ret, "error selecting gtxclk delay chain\n");
+       }
+
+       return 0;
+}
+
+static void dwmac_starfive_fix_mac_speed(void *data, unsigned int speed)
+{
+       struct dwmac_starfive *dwmac = data;
+       unsigned long rate;
+       int ret;
+
+       switch (speed) {
+       case SPEED_1000:
+               rate = 125000000;
+               break;
+       case SPEED_100:
+               rate = 25000000;
+               break;
+       case SPEED_10:
+               rate = 2500000;
+               break;
+       default:
+               dev_warn(dwmac->dev, "unsupported link speed %u\n", speed);
+               return;
+       }
+
+       ret = clk_set_rate(dwmac->gtxc, rate);
+       if (ret)
+               dev_err(dwmac->dev, "error setting gtx clock rate: %d\n", ret);
+}
+
+static int dwmac_starfive_probe(struct platform_device *pdev)
+{
+       struct stmmac_resources stmmac_res;
+       struct plat_stmmacenet_data *plat;
+       struct dwmac_starfive *dwmac;
+       struct clk *txclk;
+       int (*syscon_init)(struct device *dev);
+       int ret;
+
+       dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
+       if (!dwmac)
+               return -ENOMEM;
+
+       ret = stmmac_get_platform_resources(pdev, &stmmac_res);
+       if (ret)
+               return ret;
+
+       syscon_init = of_device_get_match_data(&pdev->dev);
+       if (syscon_init) {
+               ret = syscon_init(&pdev->dev);
+               if (ret)
+                       return ret;
+       }
+
+       dwmac->gtxc = devm_clk_get_enabled(&pdev->dev, "gtxc");
+       if (IS_ERR(dwmac->gtxc))
+               return dev_err_probe(&pdev->dev, PTR_ERR(dwmac->gtxc),
+                                    "error getting/enabling gtxc clock\n");
+
+       txclk = devm_clk_get_enabled(&pdev->dev, "tx");
+       if (IS_ERR(txclk))
+               return dev_err_probe(&pdev->dev, PTR_ERR(txclk),
+                                    "error getting/enabling tx clock\n");
+
+       plat = stmmac_probe_config_dt(pdev, stmmac_res.mac);
+       if (IS_ERR(plat))
+               return dev_err_probe(&pdev->dev, PTR_ERR(plat),
+                                    "dt configuration failed\n");
+
+       dwmac->dev = &pdev->dev;
+       plat->bsp_priv = dwmac;
+       plat->fix_mac_speed = dwmac_starfive_fix_mac_speed;
+
+       ret = stmmac_dvr_probe(&pdev->dev, plat, &stmmac_res);
+       if (ret) {
+               stmmac_remove_config_dt(pdev, plat);
+               return ret;
+       }
+
+       return 0;
+}
+
+static const struct of_device_id dwmac_starfive_match[] = {
+       {
+               .compatible = "starfive,jh7100-gmac",
+               .data = dwmac_starfive_jh7100_syscon_init,
+       },
+       {
+               .compatible = "starfive,jh7110-gmac",
+       },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, dwmac_starfive_match);
+
+static struct platform_driver dwmac_starfive_driver = {
+       .probe  = dwmac_starfive_probe,
+       .remove = stmmac_pltfr_remove,
+       .driver = {
+               .name           = "dwmac-starfive",
+               .pm             = &stmmac_pltfr_pm_ops,
+               .of_match_table = dwmac_starfive_match,
+       },
+};
+module_platform_driver(dwmac_starfive_driver);
+
+MODULE_AUTHOR("Emil Renner Berthing <kernel@esmil.dk>");
+MODULE_DESCRIPTION("StarFive DWMAC Glue Layer");
+MODULE_LICENSE("GPL");