[PATCH v2 2/2] phy: ralink: Add PHY driver for MT7621 PCIe PHY

From: Sergio Paracuellos
Date: Sat Mar 30 2019 - 01:50:54 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 | 7 +
drivers/phy/ralink/Makefile | 1 +
drivers/phy/ralink/phy-mt7621-pci.c | 401 ++++++++++++++++++++++++++++
3 files changed, 409 insertions(+)
create mode 100644 drivers/phy/ralink/phy-mt7621-pci.c

diff --git a/drivers/phy/ralink/Kconfig b/drivers/phy/ralink/Kconfig
index 14fd219535ef..87943a10f210 100644
--- a/drivers/phy/ralink/Kconfig
+++ b/drivers/phy/ralink/Kconfig
@@ -1,6 +1,13 @@
#
# PHY drivers for Ralink platforms.
#
+config PHY_MT7621_PCI
+ tristate "MediaTek MT7621 PCI PHY Driver"
+ depends on RALINK && OF
+ select GENERIC_PHY
+ 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 5c9e326e8757..2052d5649863 100644
--- a/drivers/phy/ralink/Makefile
+++ b/drivers/phy/ralink/Makefile
@@ -1 +1,2 @@
+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..118302c122ee
--- /dev/null
+++ b/drivers/phy/ralink/phy-mt7621-pci.c
@@ -0,0 +1,401 @@
+// 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/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 <mt7621.h>
+#include <ralink_regs.h>
+
+#define RALINK_CLKCFG1 0x30
+#define CHIP_REV_MT7621_E2 0x0101
+
+#define PCIE_PORT_CLK_EN(x) BIT(24 + (x))
+
+#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_H_LCDDS_PCW_VAL(x) ((0x7fffffff & (x)) << 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_H_XTAL_TYPE_VAL(x) ((0x3 & (x)) << 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_BC_VAL(x) ((0x3 & (x)) << 22)
+#define RG_PE1_H_PLL_BP GENMASK(21, 18)
+#define RG_PE1_H_PLL_BP_VAL(x) ((0xf & (x)) << 18)
+#define RG_PE1_H_PLL_IR GENMASK(15, 12)
+#define RG_PE1_H_PLL_IR_VAL(x) ((0xf & (x)) << 12)
+#define RG_PE1_H_PLL_IC GENMASK(11, 8)
+#define RG_PE1_H_PLL_IC_VAL(x) ((0xf & (x)) << 8)
+#define RG_PE1_H_PLL_PREDIV GENMASK(7, 6)
+#define RG_PE1_H_PLL_PREDIV_VAL(x) ((0x3 & (x)) << 6)
+#define RG_PE1_PLL_DIVEN GENMASK(3, 1)
+#define RG_PE1_PLL_DIVEN_VAL(x) ((0x7 & (x)) << 1)
+
+#define RG_PE1_H_PLL_FBKSEL_REG 0x4bc
+#define RG_PE1_H_PLL_FBKSEL GENMASK(5, 4)
+#define RG_PE1_H_PLL_FBKSEL_VAL(x) ((0x3 & (x)) << 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_PRD_VAL(x) ((0xffff & (x)) << 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_DELTA_VAL(x) ((0xfff & (x)) << 0)
+#define RG_PE1_H_LCDDS_SSC_DELTA1 GENMASK(27, 16)
+#define RG_PE1_H_LCDDS_SSC_DELTA1_VAL(x) ((0xff & (x)) << 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_H_PLL_BR_VAL(x) ((0x7 & (x)) << 16)
+
+#define RG_PE1_MSTCKDIV_REG 0x414
+#define RG_PE1_MSTCKDIV GENMASK(7, 6)
+#define RG_PE1_MSTCKDIV_VAL(x) ((0x3 & (x)) << 6)
+
+#define RG_PE1_FRC_MSTCKDIV BIT(5)
+
+#define MAX_PHYS 2
+
+/**
+ * struct mt7621_pci_phy_instance - Mt7621 Pcie PHY device
+ * @phy: pointer to the kernel PHY device
+ * @port_base: base register
+ * @index: internal ID to identify the Mt7621 PCIe PHY
+ */
+struct mt7621_pci_phy_instance {
+ struct phy *phy;
+ void __iomem *port_base;
+ u32 index;
+};
+
+/**
+ * struct mt7621_pci_phy - Mt7621 Pcie PHY core
+ * @dev: pointer to device
+ * @phys: pointer to Mt7621 PHY device
+ * @nphys: number of PHY devices for this core
+ */
+struct mt7621_pci_phy {
+ struct device *dev;
+ struct mt7621_pci_phy_instance **phys;
+ int nphys;
+};
+
+static inline u32 phy_read(struct mt7621_pci_phy_instance *instance, u32 reg)
+{
+ return readl(instance->port_base + reg);
+}
+
+static inline void phy_write(struct mt7621_pci_phy_instance *instance,
+ u32 val, u32 reg)
+{
+ writel(val, instance->port_base + reg);
+}
+
+static void mt7621_bypass_pipe_rst(struct mt7621_pci_phy *phy,
+ struct mt7621_pci_phy_instance *instance)
+{
+ u32 offset = (instance->index != 1) ?
+ RG_PE1_PIPE_REG : RG_PE1_PIPE_REG + RG_P0_TO_P1_WIDTH;
+ u32 reg;
+
+ reg = phy_read(instance, offset);
+ reg &= ~(RG_PE1_PIPE_RST | RG_PE1_PIPE_CMD_FRC);
+ reg |= (RG_PE1_PIPE_RST | RG_PE1_PIPE_CMD_FRC);
+ phy_write(instance, reg, offset);
+}
+
+static void mt7621_set_phy_for_ssc(struct mt7621_pci_phy *phy,
+ struct mt7621_pci_phy_instance *instance)
+{
+ struct device *dev = phy->dev;
+ u32 reg = rt_sysc_r32(SYSC_REG_SYSTEM_CONFIG0);
+ u32 offset;
+ u32 val;
+
+ reg = (reg >> 6) & 0x7;
+ /* Set PCIe Port PHY to disable SSC */
+ /* Debug Xtal Type */
+ val = phy_read(instance, RG_PE1_FRC_H_XTAL_REG);
+ val &= ~(RG_PE1_FRC_H_XTAL_TYPE | RG_PE1_H_XTAL_TYPE);
+ val |= RG_PE1_FRC_H_XTAL_TYPE;
+ val |= RG_PE1_H_XTAL_TYPE_VAL(0x00);
+ phy_write(instance, val, RG_PE1_FRC_H_XTAL_REG);
+
+ /* disable port */
+ offset = (instance->index != 1) ?
+ RG_PE1_FRC_PHY_REG : RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH;
+ val = phy_read(instance, offset);
+ val &= ~(RG_PE1_FRC_PHY_EN | RG_PE1_PHY_EN);
+ val |= RG_PE1_FRC_PHY_EN;
+ phy_write(instance, val, offset);
+
+ /* Set Pre-divider ratio (for host mode) */
+ val = phy_read(instance, RG_PE1_H_PLL_REG);
+ val &= ~(RG_PE1_H_PLL_PREDIV);
+
+ if (reg <= 5 && reg >= 3) { /* 40MHz Xtal */
+ val |= RG_PE1_H_PLL_PREDIV_VAL(0x01);
+ phy_write(instance, val, RG_PE1_H_PLL_REG);
+ dev_info(dev, "Xtal is 40MHz\n");
+ } else { /* 25MHz | 20MHz Xtal */
+ val |= RG_PE1_H_PLL_PREDIV_VAL(0x00);
+ phy_write(instance, val, RG_PE1_H_PLL_REG);
+ if (reg >= 6) {
+ dev_info(dev, "Xtal is 25MHz\n");
+
+ /* Select feedback clock */
+ val = phy_read(instance, RG_PE1_H_PLL_FBKSEL_REG);
+ val &= ~(RG_PE1_H_PLL_FBKSEL);
+ val |= RG_PE1_H_PLL_FBKSEL_VAL(0x01);
+ phy_write(instance, val, RG_PE1_H_PLL_FBKSEL_REG);
+
+ /* DDS NCPO PCW (for host mode) */
+ val = phy_read(instance, RG_PE1_H_LCDDS_SSC_PRD_REG);
+ val &= ~(RG_PE1_H_LCDDS_SSC_PRD);
+ val |= RG_PE1_H_LCDDS_SSC_PRD_VAL(0x18000000);
+ phy_write(instance, val, RG_PE1_H_LCDDS_SSC_PRD_REG);
+
+ /* DDS SSC dither period control */
+ val = phy_read(instance, RG_PE1_H_LCDDS_SSC_PRD_REG);
+ val &= ~(RG_PE1_H_LCDDS_SSC_PRD);
+ val |= RG_PE1_H_LCDDS_SSC_PRD_VAL(0x18d);
+ phy_write(instance, val, RG_PE1_H_LCDDS_SSC_PRD_REG);
+
+ /* DDS SSC dither amplitude control */
+ val = phy_read(instance, RG_PE1_H_LCDDS_SSC_DELTA_REG);
+ val &= ~(RG_PE1_H_LCDDS_SSC_DELTA |
+ RG_PE1_H_LCDDS_SSC_DELTA1);
+ val |= RG_PE1_H_LCDDS_SSC_DELTA_VAL(0x4a);
+ val |= RG_PE1_H_LCDDS_SSC_DELTA1_VAL(0x4a);
+ phy_write(instance, val, RG_PE1_H_LCDDS_SSC_DELTA_REG);
+ } else {
+ dev_info(dev, "Xtal is 20MHz\n");
+ }
+ }
+
+ /* DDS clock inversion */
+ val = phy_read(instance, RG_PE1_LCDDS_CLK_PH_INV_REG);
+ val &= ~(RG_PE1_LCDDS_CLK_PH_INV);
+ val |= RG_PE1_LCDDS_CLK_PH_INV;
+ phy_write(instance, val, RG_PE1_LCDDS_CLK_PH_INV_REG);
+
+ /* Set PLL bits */
+ val = phy_read(instance, RG_PE1_H_PLL_REG);
+ val &= ~(RG_PE1_H_PLL_BC | RG_PE1_H_PLL_BP | RG_PE1_H_PLL_IR |
+ RG_PE1_H_PLL_IC | RG_PE1_PLL_DIVEN);
+ val |= RG_PE1_H_PLL_BC_VAL(0x02);
+ val |= RG_PE1_H_PLL_BP_VAL(0x06);
+ val |= RG_PE1_H_PLL_IR_VAL(0x02);
+ val |= RG_PE1_H_PLL_IC_VAL(0x01);
+ val |= RG_PE1_PLL_DIVEN_VAL(0x02);
+ phy_write(instance, val, RG_PE1_H_PLL_REG);
+
+ val = phy_read(instance, RG_PE1_H_PLL_BR_REG);
+ val &= ~(RG_PE1_H_PLL_BR);
+ val |= RG_PE1_H_PLL_BR_VAL(0x00);
+ phy_write(instance, val, RG_PE1_H_PLL_BR_REG);
+
+ if (reg <= 5 && reg >= 3) { /* 40MHz Xtal */
+ /* set force mode enable of da_pe1_mstckdiv */
+ val = phy_read(instance, RG_PE1_MSTCKDIV_REG);
+ val &= ~(RG_PE1_MSTCKDIV | RG_PE1_FRC_MSTCKDIV);
+ val |= (RG_PE1_MSTCKDIV_VAL(0x01) | RG_PE1_FRC_MSTCKDIV);
+ phy_write(instance, val, RG_PE1_MSTCKDIV_REG);
+ }
+}
+
+static int mt7621_pci_phy_init(struct phy *phy)
+{
+ struct mt7621_pci_phy_instance *instance = phy_get_drvdata(phy);
+ struct mt7621_pci_phy *mphy = dev_get_drvdata(phy->dev.parent);
+ u32 chip_rev_id = rt_sysc_r32(SYSC_REG_CHIP_REV);
+
+ if ((chip_rev_id & 0xFFFF) == CHIP_REV_MT7621_E2)
+ mt7621_bypass_pipe_rst(mphy, instance);
+
+ mt7621_set_phy_for_ssc(mphy, instance);
+
+ return 0;
+}
+
+static int mt7621_pci_phy_power_on(struct phy *phy)
+{
+ struct mt7621_pci_phy_instance *instance = phy_get_drvdata(phy);
+ u32 offset = (instance->index != 1) ?
+ RG_PE1_FRC_PHY_REG : RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH;
+ u32 val;
+
+ /* Enable PHY and disable force mode */
+ val = phy_read(instance, offset);
+ val &= ~(RG_PE1_FRC_PHY_EN | RG_PE1_PHY_EN);
+ val |= (RG_PE1_FRC_PHY_EN | RG_PE1_PHY_EN);
+ phy_write(instance, val, offset);
+
+ return 0;
+}
+
+static int mt7621_pci_phy_power_off(struct phy *phy)
+{
+ struct mt7621_pci_phy_instance *instance = phy_get_drvdata(phy);
+ u32 offset = (instance->index != 1) ?
+ RG_PE1_FRC_PHY_REG : RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH;
+ u32 val;
+
+ /* Disable PHY */
+ val = phy_read(instance, offset);
+ val &= ~(RG_PE1_FRC_PHY_EN | RG_PE1_PHY_EN);
+ val |= RG_PE1_FRC_PHY_EN;
+ phy_write(instance, val, offset);
+
+ return 0;
+}
+
+static int mt7621_pci_phy_exit(struct phy *phy)
+{
+ struct mt7621_pci_phy_instance *instance = phy_get_drvdata(phy);
+
+ rt_sysc_m32(PCIE_PORT_CLK_EN(instance->index), 0, RALINK_CLKCFG1);
+
+ 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 (args->args_count == 0)
+ return mt7621_phy->phys[0]->phy;
+
+ if (WARN_ON(args->args[0] >= MAX_PHYS))
+ return ERR_PTR(-ENODEV);
+
+ return mt7621_phy->phys[args->args[0]]->phy;
+}
+
+static int mt7621_pci_phy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct device_node *child_np;
+ struct phy_provider *provider;
+ struct mt7621_pci_phy *phy;
+ struct resource res;
+ int port, ret;
+ void __iomem *port_base;
+
+ phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
+ if (!phy)
+ return -ENOMEM;
+
+ phy->nphys = MAX_PHYS;
+ phy->phys = devm_kcalloc(dev, phy->nphys,
+ sizeof(*phy->phys), GFP_KERNEL);
+ if (!phy->phys)
+ return -ENOMEM;
+
+ phy->dev = dev;
+ platform_set_drvdata(pdev, phy);
+
+ ret = of_address_to_resource(np, 0, &res);
+ if (ret) {
+ dev_err(dev, "failed to get address resource(id-%d)\n", port);
+ return ret;
+ }
+
+ port_base = devm_ioremap_resource(dev, &res);
+ if (IS_ERR(port_base)) {
+ dev_err(dev, "failed to remap phy regs\n");
+ return PTR_ERR(port_base);
+ }
+
+ for (port = 0; port < MAX_PHYS; port++) {
+ struct mt7621_pci_phy_instance *instance;
+ struct phy *pphy;
+
+ instance = devm_kzalloc(dev, sizeof(*instance), GFP_KERNEL);
+ if (!instance) {
+ ret = -ENOMEM;
+ goto put_child;
+ }
+
+ phy->phys[port] = instance;
+
+ pphy = devm_phy_create(dev, dev->of_node, &mt7621_pci_phy_ops);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "failed to create phy\n");
+ ret = PTR_ERR(phy);
+ goto put_child;
+ }
+
+ instance->port_base = port_base;
+ instance->phy = pphy;
+ instance->index = port;
+ phy_set_drvdata(pphy, instance);
+ }
+
+ provider = devm_of_phy_provider_register(dev, mt7621_pcie_phy_of_xlate);
+
+ return PTR_ERR_OR_ZERO(provider);
+
+put_child:
+ of_node_put(child_np);
+ return ret;
+}
+
+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),
+ },
+};
+
+static int __init mt7621_pci_phy_drv_init(void)
+{
+ return platform_driver_register(&mt7621_pci_phy_driver);
+}
+
+module_init(mt7621_pci_phy_drv_init);
+
+MODULE_AUTHOR("Sergio Paracuellos <sergio.paracuellos@xxxxxxxxx>");
+MODULE_DESCRIPTION("MediaTek MT7621 PCIe PHY driver");
+MODULE_LICENSE("GPL v2");
--
2.19.1