[PATCH v5 2/4] phy: ralink: Add PHY driver for MT7621 PCIe PHY

From: Sergio Paracuellos
Date: Thu Nov 19 2020 - 10:44:49 EST


This patch adds a driver for the PCIe PHY of MT7621 SoC.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@xxxxxxxxx>
---
drivers/phy/ralink/Kconfig | 8 +
drivers/phy/ralink/Makefile | 1 +
drivers/phy/ralink/phy-mt7621-pci.c | 346 ++++++++++++++++++++++++++++
3 files changed, 355 insertions(+)
create mode 100644 drivers/phy/ralink/phy-mt7621-pci.c

diff --git a/drivers/phy/ralink/Kconfig b/drivers/phy/ralink/Kconfig
index da982c9cffb3..2fabb14d2998 100644
--- a/drivers/phy/ralink/Kconfig
+++ b/drivers/phy/ralink/Kconfig
@@ -2,6 +2,14 @@
#
# PHY drivers for Ralink platforms.
#
+config PHY_MT7621_PCI
+ tristate "MediaTek MT7621 PCI PHY Driver"
+ depends on (RALINK || COMPILE_TEST) && OF
+ select GENERIC_PHY
+ select REGMAP_MMIO
+ help
+ Say 'Y' here to add support for MediaTek MT7621 PCI PHY driver,
+
config PHY_RALINK_USB
tristate "Ralink USB PHY driver"
depends on RALINK || COMPILE_TEST
diff --git a/drivers/phy/ralink/Makefile b/drivers/phy/ralink/Makefile
index d8d3ffcf0a15..cda2a4a7ca5e 100644
--- a/drivers/phy/ralink/Makefile
+++ b/drivers/phy/ralink/Makefile
@@ -1,2 +1,3 @@
# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_PHY_MT7621_PCI) += phy-mt7621-pci.o
obj-$(CONFIG_PHY_RALINK_USB) += phy-ralink-usb.o
diff --git a/drivers/phy/ralink/phy-mt7621-pci.c b/drivers/phy/ralink/phy-mt7621-pci.c
new file mode 100644
index 000000000000..c452bc679d53
--- /dev/null
+++ b/drivers/phy/ralink/phy-mt7621-pci.c
@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Mediatek MT7621 PCI PHY Driver
+ * Author: Sergio Paracuellos <sergio.paracuellos@xxxxxxxxx>
+ */
+
+#include <dt-bindings/phy/phy.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/sys_soc.h>
+#include <mt7621.h>
+#include <ralink_regs.h>
+
+#define RG_PE1_PIPE_REG 0x02c
+#define RG_PE1_PIPE_RST BIT(12)
+#define RG_PE1_PIPE_CMD_FRC BIT(4)
+
+#define RG_P0_TO_P1_WIDTH 0x100
+#define RG_PE1_H_LCDDS_REG 0x49c
+#define RG_PE1_H_LCDDS_PCW GENMASK(30, 0)
+
+#define RG_PE1_FRC_H_XTAL_REG 0x400
+#define RG_PE1_FRC_H_XTAL_TYPE BIT(8)
+#define RG_PE1_H_XTAL_TYPE GENMASK(10, 9)
+
+#define RG_PE1_FRC_PHY_REG 0x000
+#define RG_PE1_FRC_PHY_EN BIT(4)
+#define RG_PE1_PHY_EN BIT(5)
+
+#define RG_PE1_H_PLL_REG 0x490
+#define RG_PE1_H_PLL_BC GENMASK(23, 22)
+#define RG_PE1_H_PLL_BP GENMASK(21, 18)
+#define RG_PE1_H_PLL_IR GENMASK(15, 12)
+#define RG_PE1_H_PLL_IC GENMASK(11, 8)
+#define RG_PE1_H_PLL_PREDIV GENMASK(7, 6)
+#define RG_PE1_PLL_DIVEN GENMASK(3, 1)
+
+#define RG_PE1_H_PLL_FBKSEL_REG 0x4bc
+#define RG_PE1_H_PLL_FBKSEL GENMASK(5, 4)
+
+#define RG_PE1_H_LCDDS_SSC_PRD_REG 0x4a4
+#define RG_PE1_H_LCDDS_SSC_PRD GENMASK(15, 0)
+
+#define RG_PE1_H_LCDDS_SSC_DELTA_REG 0x4a8
+#define RG_PE1_H_LCDDS_SSC_DELTA GENMASK(11, 0)
+#define RG_PE1_H_LCDDS_SSC_DELTA1 GENMASK(27, 16)
+
+#define RG_PE1_LCDDS_CLK_PH_INV_REG 0x4a0
+#define RG_PE1_LCDDS_CLK_PH_INV BIT(5)
+
+#define RG_PE1_H_PLL_BR_REG 0x4ac
+#define RG_PE1_H_PLL_BR GENMASK(18, 16)
+
+#define RG_PE1_MSTCKDIV_REG 0x414
+#define RG_PE1_MSTCKDIV GENMASK(7, 6)
+
+#define RG_PE1_FRC_MSTCKDIV BIT(5)
+
+#define XTAL_MODE_SEL_MASK 0x7
+
+#define MAX_PHYS 2
+
+/**
+ * struct mt7621_pci_phy - Mt7621 Pcie PHY core
+ * @dev: pointer to device
+ * @regmap: kernel regmap pointer
+ * @phy: pointer to the kernel PHY device
+ * @port_base: base register
+ * @has_dual_port: if the phy has dual ports.
+ * @bypass_pipe_rst: mark if 'mt7621_bypass_pipe_rst'
+ * needs to be executed. Depends on chip revision.
+ */
+struct mt7621_pci_phy {
+ struct device *dev;
+ struct regmap *regmap;
+ struct phy *phy;
+ void __iomem *port_base;
+ bool has_dual_port;
+ bool bypass_pipe_rst;
+};
+
+static inline void mt7621_phy_rmw(struct mt7621_pci_phy *phy,
+ u32 reg, u32 clr, u32 set)
+{
+ u32 val;
+
+ regmap_read(phy->regmap, reg, &val);
+
+ val &= ~clr;
+ val |= set;
+ regmap_write(phy->regmap, reg, val);
+}
+
+static void mt7621_bypass_pipe_rst(struct mt7621_pci_phy *phy)
+{
+ mt7621_phy_rmw(phy, RG_PE1_PIPE_REG, 0, RG_PE1_PIPE_RST);
+ mt7621_phy_rmw(phy, RG_PE1_PIPE_REG, 0, RG_PE1_PIPE_CMD_FRC);
+
+ if (phy->has_dual_port) {
+ mt7621_phy_rmw(phy, RG_PE1_PIPE_REG + RG_P0_TO_P1_WIDTH,
+ 0, RG_PE1_PIPE_RST);
+ mt7621_phy_rmw(phy, RG_PE1_PIPE_REG + RG_P0_TO_P1_WIDTH,
+ 0, RG_PE1_PIPE_CMD_FRC);
+ }
+}
+
+static void mt7621_set_phy_for_ssc(struct mt7621_pci_phy *phy)
+{
+ struct device *dev = phy->dev;
+ u32 xtal_mode;
+
+ xtal_mode = FIELD_GET(XTAL_MODE_SEL_MASK,
+ rt_sysc_r32(SYSC_REG_SYSTEM_CONFIG0));
+
+ /* Set PCIe Port PHY to disable SSC */
+ /* Debug Xtal Type */
+ mt7621_phy_rmw(phy, RG_PE1_FRC_H_XTAL_REG,
+ RG_PE1_FRC_H_XTAL_TYPE | RG_PE1_H_XTAL_TYPE,
+ FIELD_PREP(RG_PE1_FRC_H_XTAL_TYPE, 0x00));
+
+ /* disable port */
+ mt7621_phy_rmw(phy, RG_PE1_FRC_PHY_REG, RG_PE1_PHY_EN,
+ RG_PE1_FRC_PHY_EN);
+
+ if (phy->has_dual_port) {
+ mt7621_phy_rmw(phy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH,
+ RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN);
+ }
+
+ if (xtal_mode <= 5 && xtal_mode >= 3) { /* 40MHz Xtal */
+ /* Set Pre-divider ratio (for host mode) */
+ mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV,
+ FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x01));
+
+ dev_dbg(dev, "Xtal is 40MHz\n");
+ } else if (xtal_mode >= 6) { /* 25MHz Xal */
+ mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV,
+ FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x00));
+
+ /* Select feedback clock */
+ mt7621_phy_rmw(phy, RG_PE1_H_PLL_FBKSEL_REG,
+ RG_PE1_H_PLL_FBKSEL,
+ FIELD_PREP(RG_PE1_H_PLL_FBKSEL, 0x01));
+
+ /* DDS NCPO PCW (for host mode) */
+ mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_PRD_REG,
+ RG_PE1_H_LCDDS_SSC_PRD,
+ FIELD_PREP(RG_PE1_H_LCDDS_SSC_PRD, 0x00));
+
+ /* DDS SSC dither period control */
+ mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_PRD_REG,
+ RG_PE1_H_LCDDS_SSC_PRD,
+ FIELD_PREP(RG_PE1_H_LCDDS_SSC_PRD, 0x18d));
+
+ /* DDS SSC dither amplitude control */
+ mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_DELTA_REG,
+ RG_PE1_H_LCDDS_SSC_DELTA |
+ RG_PE1_H_LCDDS_SSC_DELTA1,
+ FIELD_PREP(RG_PE1_H_LCDDS_SSC_DELTA, 0x4a) |
+ FIELD_PREP(RG_PE1_H_LCDDS_SSC_DELTA1, 0x4a));
+
+ dev_dbg(dev, "Xtal is 25MHz\n");
+ } else { /* 20MHz Xtal */
+ mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV,
+ FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x00));
+
+ dev_dbg(dev, "Xtal is 20MHz\n");
+ }
+
+ /* DDS clock inversion */
+ mt7621_phy_rmw(phy, RG_PE1_LCDDS_CLK_PH_INV_REG,
+ RG_PE1_LCDDS_CLK_PH_INV, RG_PE1_LCDDS_CLK_PH_INV);
+
+ /* Set PLL bits */
+ mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG,
+ RG_PE1_H_PLL_BC | RG_PE1_H_PLL_BP | RG_PE1_H_PLL_IR |
+ RG_PE1_H_PLL_IC | RG_PE1_PLL_DIVEN,
+ FIELD_PREP(RG_PE1_H_PLL_BC, 0x02) |
+ FIELD_PREP(RG_PE1_H_PLL_BP, 0x06) |
+ FIELD_PREP(RG_PE1_H_PLL_IR, 0x02) |
+ FIELD_PREP(RG_PE1_H_PLL_IC, 0x01) |
+ FIELD_PREP(RG_PE1_PLL_DIVEN, 0x02));
+
+ mt7621_phy_rmw(phy, RG_PE1_H_PLL_BR_REG,
+ RG_PE1_H_PLL_BR, FIELD_PREP(RG_PE1_H_PLL_BR, 0x00));
+
+ if (xtal_mode <= 5 && xtal_mode >= 3) { /* 40MHz Xtal */
+ /* set force mode enable of da_pe1_mstckdiv */
+ mt7621_phy_rmw(phy, RG_PE1_MSTCKDIV_REG,
+ RG_PE1_MSTCKDIV | RG_PE1_FRC_MSTCKDIV,
+ FIELD_PREP(RG_PE1_MSTCKDIV, 0x01) |
+ RG_PE1_FRC_MSTCKDIV);
+ }
+}
+
+static int mt7621_pci_phy_init(struct phy *phy)
+{
+ struct mt7621_pci_phy *mphy = phy_get_drvdata(phy);
+
+ if (mphy->bypass_pipe_rst)
+ mt7621_bypass_pipe_rst(mphy);
+
+ mt7621_set_phy_for_ssc(mphy);
+
+ return 0;
+}
+
+static int mt7621_pci_phy_power_on(struct phy *phy)
+{
+ struct mt7621_pci_phy *mphy = phy_get_drvdata(phy);
+
+ /* Enable PHY and disable force mode */
+ mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG,
+ RG_PE1_FRC_PHY_EN, RG_PE1_PHY_EN);
+
+ if (mphy->has_dual_port) {
+ mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH,
+ RG_PE1_FRC_PHY_EN, RG_PE1_PHY_EN);
+ }
+
+ return 0;
+}
+
+static int mt7621_pci_phy_power_off(struct phy *phy)
+{
+ struct mt7621_pci_phy *mphy = phy_get_drvdata(phy);
+
+ /* Disable PHY */
+ mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG,
+ RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN);
+
+ if (mphy->has_dual_port) {
+ mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH,
+ RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN);
+ }
+
+ return 0;
+}
+
+static int mt7621_pci_phy_exit(struct phy *phy)
+{
+ return 0;
+}
+
+static const struct phy_ops mt7621_pci_phy_ops = {
+ .init = mt7621_pci_phy_init,
+ .exit = mt7621_pci_phy_exit,
+ .power_on = mt7621_pci_phy_power_on,
+ .power_off = mt7621_pci_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static struct phy *mt7621_pcie_phy_of_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct mt7621_pci_phy *mt7621_phy = dev_get_drvdata(dev);
+
+ if (WARN_ON(args->args[0] >= MAX_PHYS))
+ return ERR_PTR(-ENODEV);
+
+ mt7621_phy->has_dual_port = args->args[0];
+
+ dev_info(dev, "PHY for 0x%08x (dual port = %d)\n",
+ (unsigned int)mt7621_phy->port_base, mt7621_phy->has_dual_port);
+
+ return mt7621_phy->phy;
+}
+
+static const struct soc_device_attribute mt7621_pci_quirks_match[] = {
+ { .soc_id = "mt7621", .revision = "E2" }
+};
+
+static const struct regmap_config mt7621_pci_phy_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = 0x700,
+};
+
+static int mt7621_pci_phy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ const struct soc_device_attribute *attr;
+ struct phy_provider *provider;
+ struct mt7621_pci_phy *phy;
+
+ phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
+ if (!phy)
+ return -ENOMEM;
+
+ attr = soc_device_match(mt7621_pci_quirks_match);
+ if (attr)
+ phy->bypass_pipe_rst = true;
+
+ phy->dev = dev;
+ platform_set_drvdata(pdev, phy);
+
+ phy->port_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(phy->port_base)) {
+ dev_err(dev, "failed to remap phy regs\n");
+ return PTR_ERR(phy->port_base);
+ }
+
+ phy->regmap = devm_regmap_init_mmio(phy->dev, phy->port_base,
+ &mt7621_pci_phy_regmap_config);
+ if (IS_ERR(phy->regmap))
+ return PTR_ERR(phy->regmap);
+
+ phy->phy = devm_phy_create(dev, dev->of_node, &mt7621_pci_phy_ops);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "failed to create phy\n");
+ return PTR_ERR(phy);
+ }
+
+ phy_set_drvdata(phy->phy, phy);
+
+ provider = devm_of_phy_provider_register(dev, mt7621_pcie_phy_of_xlate);
+
+ return PTR_ERR_OR_ZERO(provider);
+}
+
+static const struct of_device_id mt7621_pci_phy_ids[] = {
+ { .compatible = "mediatek,mt7621-pci-phy" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mt7621_pci_ids);
+
+static struct platform_driver mt7621_pci_phy_driver = {
+ .probe = mt7621_pci_phy_probe,
+ .driver = {
+ .name = "mt7621-pci-phy",
+ .of_match_table = of_match_ptr(mt7621_pci_phy_ids),
+ },
+};
+
+builtin_platform_driver(mt7621_pci_phy_driver);
+
+MODULE_AUTHOR("Sergio Paracuellos <sergio.paracuellos@xxxxxxxxx>");
+MODULE_DESCRIPTION("MediaTek MT7621 PCIe PHY driver");
+MODULE_LICENSE("GPL v2");
--
2.25.1