[PATCH v2 5/5] net: stmmac: Add NXP S32 SoC family support

[Chester Lin]

Add GMAC support for NXP S32 SoC family. This driver is mainly based on
NXP's downstream implementation on CodeAurora[1].

[1] https://source.codeaurora.org/external/autobsps32/linux/tree/drivers/net/ethernet/stmicro/stmmac?h=bsp34.0-5.10.120-rt

Signed-off-by: Jan Petrous <jan.petrous@xxxxxxx>
Signed-off-by: Ghennadi Procopciuc <Ghennadi.Procopciuc@xxxxxxx>
Signed-off-by: Andra-Teodora Ilie <andra.ilie@xxxxxxx>
Signed-off-by: Chester Lin <clin@xxxxxxxx>
---

Changes in v2:
- Replace clock names tx_sgmii/rx_sgmii with tx_pcs/rx_pcs.
- Adjust error handlings while calling devm_clk_get().
- Remove redundant dev_info messages.
- Remove unnecessary if conditions.
- Fix the copyright format suggested by NXP.

 drivers/net/ethernet/stmicro/stmmac/Kconfig   |  13 +
 drivers/net/ethernet/stmicro/stmmac/Makefile  |   1 +
 .../net/ethernet/stmicro/stmmac/dwmac-s32cc.c | 304 ++++++++++++++++++
 3 files changed, 318 insertions(+)
 create mode 100644 drivers/net/ethernet/stmicro/stmmac/dwmac-s32cc.c

diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
index 31ff35174034..dd3fb5e462b7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
+++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
@@ -153,6 +153,19 @@ config DWMAC_ROCKCHIP
 	  This selects the Rockchip RK3288 SoC glue layer support for
 	  the stmmac device driver.
 
+config DWMAC_S32CC
+	tristate "NXP S32 series GMAC support"
+	default ARCH_S32
+	depends on OF && (ARCH_S32 || COMPILE_TEST)
+	select MFD_SYSCON
+	select PHYLINK
+	help
+	  Support for ethernet controller on NXP S32 series SOCs.
+
+	  This selects NXP SoC glue layer support for the stmmac
+	  device driver. This driver is used for the S32 series
+	  SOCs GMAC ethernet controller.
+
 config DWMAC_SOCFPGA
 	tristate "SOCFPGA dwmac support"
 	default ARCH_INTEL_SOCFPGA
diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
index d4e12e9ace4f..ec92cc2becd7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Makefile
+++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_DWMAC_INTEL_PLAT)	+= dwmac-intel-plat.o
 obj-$(CONFIG_DWMAC_GENERIC)	+= dwmac-generic.o
 obj-$(CONFIG_DWMAC_IMX8)	+= dwmac-imx.o
 obj-$(CONFIG_DWMAC_VISCONTI)	+= dwmac-visconti.o
+obj-$(CONFIG_DWMAC_S32CC)	+= dwmac-s32cc.o
 stmmac-platform-objs:= stmmac_platform.o
 dwmac-altr-socfpga-objs := altr_tse_pcs.o dwmac-socfpga.o
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-s32cc.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-s32cc.c
new file mode 100644
index 000000000000..92a132ad985a
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-s32cc.c
@@ -0,0 +1,304 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * DWMAC Specific Glue layer for NXP S32 Common Chassis
+ *
+ * Copyright 2019-2022 NXP
+ * Copyright (C) 2022 SUSE LLC
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/ethtool.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_net.h>
+#include <linux/of_address.h>
+#include <linux/stmmac.h>
+
+#include "stmmac_platform.h"
+
+#define GMAC_TX_RATE_125M	125000000	/* 125MHz */
+#define GMAC_TX_RATE_25M	25000000	/* 25MHz */
+#define GMAC_TX_RATE_2M5	2500000		/* 2.5MHz */
+
+/* S32 SRC register for phyif selection */
+#define PHY_INTF_SEL_MII        0x00
+#define PHY_INTF_SEL_SGMII      0x01
+#define PHY_INTF_SEL_RGMII      0x02
+#define PHY_INTF_SEL_RMII       0x08
+
+/* AXI4 ACE control settings */
+#define ACE_DOMAIN_SIGNAL	0x2
+#define ACE_CACHE_SIGNAL	0xf
+#define ACE_CONTROL_SIGNALS	((ACE_DOMAIN_SIGNAL << 4) | ACE_CACHE_SIGNAL)
+#define ACE_PROTECTION		0x2
+
+struct s32cc_priv_data {
+	void __iomem *ctrl_sts;
+	struct device *dev;
+	phy_interface_t intf_mode;
+	struct clk *tx_clk;
+	struct clk *rx_clk;
+};
+
+static int s32cc_gmac_init(struct platform_device *pdev, void *priv)
+{
+	struct s32cc_priv_data *gmac = priv;
+	u32 intf_sel;
+	int ret;
+
+	ret = clk_prepare_enable(gmac->tx_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't enable tx clock\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(gmac->rx_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't enable rx clock\n");
+		return ret;
+	}
+
+	/* set interface mode */
+	switch (gmac->intf_mode) {
+	case PHY_INTERFACE_MODE_SGMII:
+		intf_sel = PHY_INTF_SEL_SGMII;
+		break;
+	case PHY_INTERFACE_MODE_RGMII:
+	case PHY_INTERFACE_MODE_RGMII_ID:
+	case PHY_INTERFACE_MODE_RGMII_TXID:
+	case PHY_INTERFACE_MODE_RGMII_RXID:
+		intf_sel = PHY_INTF_SEL_RGMII;
+		break;
+	case PHY_INTERFACE_MODE_RMII:
+		intf_sel = PHY_INTF_SEL_RMII;
+		break;
+	case PHY_INTERFACE_MODE_MII:
+		intf_sel = PHY_INTF_SEL_MII;
+		break;
+	default:
+		dev_err(&pdev->dev, "Unsupported PHY interface: %s\n",
+			phy_modes(gmac->intf_mode));
+		return -EINVAL;
+	}
+
+	writel(intf_sel, gmac->ctrl_sts);
+
+	dev_dbg(&pdev->dev, "PHY mode set to %s\n", phy_modes(gmac->intf_mode));
+
+	return 0;
+}
+
+static void s32cc_gmac_exit(struct platform_device *pdev, void *priv)
+{
+	struct s32cc_priv_data *gmac = priv;
+
+	clk_disable_unprepare(gmac->tx_clk);
+	clk_disable_unprepare(gmac->rx_clk);
+}
+
+static void s32cc_fix_speed(void *priv, unsigned int speed)
+{
+	struct s32cc_priv_data *gmac = priv;
+
+	/* SGMII mode doesn't support the clock reconfiguration */
+	if (gmac->intf_mode == PHY_INTERFACE_MODE_SGMII)
+		return;
+
+	switch (speed) {
+	case SPEED_1000:
+		dev_info(gmac->dev, "Set TX clock to 125M\n");
+		clk_set_rate(gmac->tx_clk, GMAC_TX_RATE_125M);
+		break;
+	case SPEED_100:
+		dev_info(gmac->dev, "Set TX clock to 25M\n");
+		clk_set_rate(gmac->tx_clk, GMAC_TX_RATE_25M);
+		break;
+	case SPEED_10:
+		dev_info(gmac->dev, "Set TX clock to 2.5M\n");
+		clk_set_rate(gmac->tx_clk, GMAC_TX_RATE_2M5);
+		break;
+	default:
+		dev_err(gmac->dev, "Unsupported/Invalid speed: %d\n", speed);
+		return;
+	}
+}
+
+static int s32cc_config_cache_coherency(struct platform_device *pdev,
+					struct plat_stmmacenet_data *plat_dat)
+{
+	plat_dat->axi4_ace_ctrl =
+		devm_kzalloc(&pdev->dev,
+			     sizeof(struct stmmac_axi4_ace_ctrl),
+			     GFP_KERNEL);
+
+	if (!plat_dat->axi4_ace_ctrl)
+		return -ENOMEM;
+
+	plat_dat->axi4_ace_ctrl->tx_ar_reg = (ACE_CONTROL_SIGNALS << 16)
+		| (ACE_CONTROL_SIGNALS << 8) | ACE_CONTROL_SIGNALS;
+
+	plat_dat->axi4_ace_ctrl->rx_aw_reg = (ACE_CONTROL_SIGNALS << 24)
+		| (ACE_CONTROL_SIGNALS << 16) | (ACE_CONTROL_SIGNALS << 8)
+		| ACE_CONTROL_SIGNALS;
+
+	plat_dat->axi4_ace_ctrl->txrx_awar_reg = (ACE_PROTECTION << 20)
+		| (ACE_PROTECTION << 16) | (ACE_CONTROL_SIGNALS << 8)
+		| ACE_CONTROL_SIGNALS;
+
+	return 0;
+}
+
+static int s32cc_dwmac_probe(struct platform_device *pdev)
+{
+	struct plat_stmmacenet_data *plat_dat;
+	struct stmmac_resources stmmac_res;
+	struct s32cc_priv_data *gmac;
+	struct resource *res;
+	const char *tx_clk, *rx_clk;
+	int ret;
+
+	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
+	if (ret)
+		return ret;
+
+	gmac = devm_kzalloc(&pdev->dev, sizeof(*gmac), GFP_KERNEL);
+	if (!gmac)
+		return PTR_ERR(gmac);
+
+	gmac->dev = &pdev->dev;
+
+	/* S32G control reg */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	gmac->ctrl_sts = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR_OR_NULL(gmac->ctrl_sts)) {
+		dev_err(&pdev->dev, "S32CC config region is missing\n");
+		return PTR_ERR(gmac->ctrl_sts);
+	}
+
+	plat_dat = stmmac_probe_config_dt(pdev, stmmac_res.mac);
+	if (IS_ERR(plat_dat))
+		return PTR_ERR(plat_dat);
+
+	plat_dat->bsp_priv = gmac;
+
+	switch (plat_dat->phy_interface) {
+	case PHY_INTERFACE_MODE_SGMII:
+		tx_clk = "tx_pcs";
+		rx_clk = "rx_pcs";
+		break;
+	case PHY_INTERFACE_MODE_RGMII:
+	case PHY_INTERFACE_MODE_RGMII_ID:
+	case PHY_INTERFACE_MODE_RGMII_TXID:
+	case PHY_INTERFACE_MODE_RGMII_RXID:
+		tx_clk = "tx_rgmii";
+		rx_clk = "rx_rgmii";
+		break;
+	case PHY_INTERFACE_MODE_RMII:
+		tx_clk = "tx_rmii";
+		rx_clk = "rx_rmii";
+		break;
+	case PHY_INTERFACE_MODE_MII:
+		tx_clk = "tx_mii";
+		rx_clk = "rx_mii";
+		break;
+	default:
+		dev_err(&pdev->dev, "Not supported phy interface mode: [%s]\n",
+			phy_modes(plat_dat->phy_interface));
+		return -EINVAL;
+	};
+
+	gmac->intf_mode = plat_dat->phy_interface;
+
+	/* DMA cache coherency settings */
+	if (of_dma_is_coherent(pdev->dev.of_node)) {
+		ret = s32cc_config_cache_coherency(pdev, plat_dat);
+		if (ret)
+			goto err_remove_config_dt;
+	}
+
+	/* tx clock */
+	gmac->tx_clk = devm_clk_get(&pdev->dev, tx_clk);
+	if (IS_ERR(gmac->tx_clk)) {
+		dev_err(&pdev->dev, "Get TX clock failed\n");
+		ret = PTR_ERR(gmac->tx_clk);
+		goto err_remove_config_dt;
+	}
+
+	/* rx clock */
+	gmac->rx_clk = devm_clk_get(&pdev->dev, rx_clk);
+	if (IS_ERR(gmac->rx_clk)) {
+		dev_err(&pdev->dev, "Get RX clock failed\n");
+		ret = PTR_ERR(gmac->rx_clk);
+		goto err_remove_config_dt;
+	}
+
+	ret = s32cc_gmac_init(pdev, gmac);
+	if (ret)
+		goto err_remove_config_dt;
+
+	/* core feature set */
+	plat_dat->has_gmac4 = true;
+	plat_dat->pmt = 1;
+
+	plat_dat->init = s32cc_gmac_init;
+	plat_dat->exit = s32cc_gmac_exit;
+	plat_dat->fix_mac_speed = s32cc_fix_speed;
+
+	/* safety feature config */
+	plat_dat->safety_feat_cfg =
+		devm_kzalloc(&pdev->dev, sizeof(*plat_dat->safety_feat_cfg),
+			     GFP_KERNEL);
+
+	if (!plat_dat->safety_feat_cfg) {
+		dev_err(&pdev->dev, "Allocate safety_feat_cfg failed\n");
+		goto err_gmac_exit;
+	}
+
+	plat_dat->safety_feat_cfg->tsoee = 1;
+	plat_dat->safety_feat_cfg->mrxpee = 1;
+	plat_dat->safety_feat_cfg->mestee = 1;
+	plat_dat->safety_feat_cfg->mrxee = 1;
+	plat_dat->safety_feat_cfg->mtxee = 1;
+	plat_dat->safety_feat_cfg->epsi = 1;
+	plat_dat->safety_feat_cfg->edpp = 1;
+	plat_dat->safety_feat_cfg->prtyen = 1;
+	plat_dat->safety_feat_cfg->tmouten = 1;
+
+	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
+	if (ret)
+		goto err_gmac_exit;
+
+	return 0;
+
+err_gmac_exit:
+	s32cc_gmac_exit(pdev, plat_dat->bsp_priv);
+err_remove_config_dt:
+	stmmac_remove_config_dt(pdev, plat_dat);
+	return ret;
+}
+
+static const struct of_device_id s32_dwmac_match[] = {
+	{ .compatible = "nxp,s32cc-dwmac" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, s32_dwmac_match);
+
+static struct platform_driver s32_dwmac_driver = {
+	.probe  = s32cc_dwmac_probe,
+	.remove = stmmac_pltfr_remove,
+	.driver = {
+		.name           = "s32cc-dwmac",
+		.pm		= &stmmac_pltfr_pm_ops,
+		.of_match_table = s32_dwmac_match,
+	},
+};
+module_platform_driver(s32_dwmac_driver);
+
+MODULE_AUTHOR("Jan Petrous <jan.petrous@xxxxxxx>");
+MODULE_DESCRIPTION("NXP S32 common chassis GMAC driver");
+MODULE_LICENSE("GPL v2");
-- 
2.37.3