The MiPHY28lp is a Generic PHY which can serve various SATA or PCIe or USB3 devices. Signed-off-by: alexandre torgue <alexandre.torgue@xxxxxx> Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx> Signed-off-by: Gabriel Fernandez <gabriel.fernandez@xxxxxxxxxx> --- .../devicetree/bindings/phy/phy-miphy28lp.txt | 2 +- drivers/phy/Kconfig | 8 + drivers/phy/Makefile | 1 + drivers/phy/phy-miphy28lp.c | 1174 ++++++++++++++++++++ 4 files changed, 1184 insertions(+), 1 deletion(-) create mode 100644 drivers/phy/phy-miphy28lp.c diff --git a/Documentation/devicetree/bindings/phy/phy-miphy28lp.txt b/Documentation/devicetree/bindings/phy/phy-miphy28lp.txt index f7cfc5f..1ad4433 100644 --- a/Documentation/devicetree/bindings/phy/phy-miphy28lp.txt +++ b/Documentation/devicetree/bindings/phy/phy-miphy28lp.txt @@ -23,7 +23,7 @@ Required properties (port (child) node): - MIPHY_TYPE_USB3 - reg : Address and length of the register set for the device. - reg-names : The names of the register addresses corresponding to the registers - filled in "reg". Is can also contain the offset of the system configuration + filled in "reg". It can also contain the offset of the system configuration registers used as glue-logic to setup the device for SATA/PCIe or USB3 devices. - resets : phandle to the parent reset controller. diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig index 2a436e6..cfaced9 100644 --- a/drivers/phy/Kconfig +++ b/drivers/phy/Kconfig @@ -38,6 +38,14 @@ config PHY_MVEBU_SATA depends on OF select GENERIC_PHY +config PHY_MIPHY28LP + tristate "STMicroelectronics MIPHY28LP PHY driver for STiH407" + depends on ARCH_STI + select GENERIC_PHY + help + Enable this to support the miphy transceiver (for SATA/PCIE/USB3) + that is part of STMicroelectronics STiH407 SoC. + config PHY_MIPHY365X tristate "STMicroelectronics MIPHY365X PHY driver for STiH41x series" depends on ARCH_STI diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile index c4590fc..30d90a8 100644 --- a/drivers/phy/Makefile +++ b/drivers/phy/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_BCM_KONA_USB2_PHY) += phy-bcm-kona-usb2.o obj-$(CONFIG_PHY_EXYNOS_DP_VIDEO) += phy-exynos-dp-video.o obj-$(CONFIG_PHY_EXYNOS_MIPI_VIDEO) += phy-exynos-mipi-video.o obj-$(CONFIG_PHY_MVEBU_SATA) += phy-mvebu-sata.o +obj-$(CONFIG_PHY_MIPHY28LP) += phy-miphy28lp.o obj-$(CONFIG_PHY_MIPHY365X) += phy-miphy365x.o obj-$(CONFIG_PHY_RCAR_GEN2) += phy-rcar-gen2.o obj-$(CONFIG_OMAP_CONTROL_PHY) += phy-omap-control.o diff --git a/drivers/phy/phy-miphy28lp.c b/drivers/phy/phy-miphy28lp.c new file mode 100644 index 0000000..b9816d5 --- /dev/null +++ b/drivers/phy/phy-miphy28lp.c @@ -0,0 +1,1174 @@ +/* + * Copyright (C) 2014 STMicroelectronics + * + * STMicroelectronics PHY driver MiPHY28lp (for SoC STiH407). + * + * Author: Alexandre Torgue <alexandre.torgue@xxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2, as + * published by the Free Software Foundation. + * + */ + +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/of_address.h> +#include <linux/clk.h> +#include <linux/phy/phy.h> +#include <linux/delay.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> +#include <linux/reset.h> + +#include <dt-bindings/phy/phy.h> + +/* MiPHY registers */ +#define MIPHY_CONF_RESET 0x00 +#define RST_APPLI_SW BIT(0) +#define RST_CONF_SW BIT(1) +#define RST_MACRO_SW BIT(2) + +#define MIPHY_RESET 0x01 +#define RST_PLL_SW BIT(0) +#define RST_COMP_SW BIT(2) + +#define MIPHY_STATUS_1 0x02 +#define PHY_RDY BIT(0) +#define HFC_RDY BIT(1) +#define HFC_PLL BIT(2) + +#define MIPHY_CONTROL 0x04 +#define TERM_EN_SW BIT(2) +#define DIS_LINK_RST BIT(3) +#define AUTO_RST_RX BIT(4) +#define PX_RX_POL BIT(5) + +#define MIPHY_BOUNDARY_SEL 0x0a +#define TX_SEL BIT(6) +#define SSC_SEL BIT(4) +#define GENSEL_SEL BIT(0) + +#define MIPHY_BOUNDARY_1 0x0b +#define MIPHY_BOUNDARY_2 0x0c +#define SSC_EN_SW BIT(2) + +#define MIPHY_PLL_CLKREF_FREQ 0x0d +#define MIPHY_SPEED 0x0e +#define TX_SPDSEL_80DEC 0 +#define TX_SPDSEL_40DEC 1 +#define TX_SPDSEL_20DEC 2 +#define RX_SPDSEL_80DEC 0 +#define RX_SPDSEL_40DEC (1 << 2) +#define RX_SPDSEL_20DEC (2 << 2) + +#define MIPHY_CONF 0x0f +#define MIPHY_CTRL_TEST_SEL 0x20 +#define MIPHY_CTRL_TEST_1 0x21 +#define MIPHY_CTRL_TEST_2 0x22 +#define MIPHY_CTRL_TEST_3 0x23 +#define MIPHY_CTRL_TEST_4 0x24 +#define MIPHY_FEEDBACK_TEST 0x25 +#define MIPHY_DEBUG_BUS 0x26 +#define MIPHY_DEBUG_STATUS_MSB 0x27 +#define MIPHY_DEBUG_STATUS_LSB 0x28 +#define MIPHY_PWR_RAIL_1 0x29 +#define MIPHY_PWR_RAIL_2 0x2a +#define MIPHY_SYNCHAR_CONTROL 0x30 + +#define MIPHY_COMP_FSM_1 0x3a +#define COMP_START BIT(6) + +#define MIPHY_COMP_FSM_6 0x3f +#define COMP_DONE BIT(7) + +#define MIPHY_COMP_POSTP 0x42 +#define MIPHY_TX_CTRL_1 0x49 +#define TX_REG_STEP_0V 0 +#define TX_REG_STEP_P_25MV 1 +#define TX_REG_STEP_P_50MV 2 +#define TX_REG_STEP_N_25MV 7 +#define TX_REG_STEP_N_50MV 6 +#define TX_REG_STEP_N_75MV 5 + +#define MIPHY_TX_CTRL_2 0x4a +#define TX_SLEW_SW_40_PS 0 +#define TX_SLEW_SW_80_PS 1 +#define TX_SLEW_SW_120_PS 2 + +#define MIPHY_TX_CTRL_3 0x4b +#define MIPHY_TX_CAL_MAN 0x4e +#define TX_SLEW_CAL_MAN_EN BIT(0) + +#define MIPHY_TST_BIAS_BOOST_2 0x62 +#define MIPHY_BIAS_BOOST_1 0x63 +#define MIPHY_BIAS_BOOST_2 0x64 +#define MIPHY_RX_DESBUFF_FDB_2 0x67 +#define MIPHY_RX_DESBUFF_FDB_3 0x68 +#define MIPHY_SIGDET_COMPENS1 0x69 +#define MIPHY_SIGDET_COMPENS2 0x6a +#define MIPHY_JITTER_PERIOD 0x6b +#define MIPHY_JITTER_AMPLITUDE_1 0x6c +#define MIPHY_JITTER_AMPLITUDE_2 0x6d +#define MIPHY_JITTER_AMPLITUDE_3 0x6e +#define MIPHY_RX_K_GAIN 0x78 +#define MIPHY_RX_BUFFER_CTRL 0x7a +#define VGA_GAIN BIT(0) +#define EQ_DC_GAIN BIT(2) +#define EQ_BOOST_GAIN BIT(3) + +#define MIPHY_RX_VGA_GAIN 0x7b +#define MIPHY_RX_EQU_GAIN_1 0x7f +#define MIPHY_RX_EQU_GAIN_2 0x80 +#define MIPHY_RX_EQU_GAIN_3 0x81 +#define MIPHY_RX_CAL_CTRL_1 0x97 +#define MIPHY_RX_CAL_CTRL_2 0x98 + +#define MIPHY_RX_CAL_OFFSET_CTRL 0x99 +#define CAL_OFFSET_VGA_64 (0x03 << 0) +#define CAL_OFFSET_THRESHOLD_64 (0x03 << 2) +#define VGA_OFFSET_POLARITY BIT(4) +#define OFFSET_COMPENSATION_EN BIT(6) + +#define MIPHY_RX_CAL_VGA_STEP 0x9a +#define MIPHY_RX_CAL_EYE_MIN 0x9d +#define MIPHY_RX_CAL_OPT_LENGTH 0x9f +#define MIPHY_RX_LOCK_CTRL_1 0xc1 +#define MIPHY_RX_LOCK_SETTINGS_OPT 0xc2 +#define MIPHY_RX_LOCK_STEP 0xc4 + +#define MIPHY_RX_SIGDET_SLEEP_OA 0xc9 +#define MIPHY_RX_SIGDET_SLEEP_SEL 0xca +#define MIPHY_RX_SIGDET_WAIT_SEL 0xcb +#define MIPHY_RX_SIGDET_DATA_SEL 0xcc +#define EN_ULTRA_LOW_POWER BIT(0) +#define EN_FIRST_HALF BIT(1) +#define EN_SECOND_HALF BIT(2) +#define EN_DIGIT_SIGNAL_CHECK BIT(3) + +#define MIPHY_RX_POWER_CTRL_1 0xcd +#define MIPHY_RX_POWER_CTRL_2 0xce +#define MIPHY_PLL_CALSET_CTRL 0xd3 +#define MIPHY_PLL_CALSET_1 0xd4 +#define MIPHY_PLL_CALSET_2 0xd5 +#define MIPHY_PLL_CALSET_3 0xd6 +#define MIPHY_PLL_CALSET_4 0xd7 +#define MIPHY_PLL_SBR_1 0xe3 +#define SET_NEW_CHANGE BIT(1) + +#define MIPHY_PLL_SBR_2 0xe4 +#define MIPHY_PLL_SBR_3 0xe5 +#define MIPHY_PLL_SBR_4 0xe6 +#define MIPHY_PLL_COMMON_MISC_2 0xe9 +#define START_ACT_FILT BIT(6) + +#define MIPHY_PLL_SPAREIN 0xeb + +/* + * On STiH407 the glue logic can be different among MiPHY devices; for example: + * MiPHY0: OSC_FORCE_EXT means: + * 0: 30MHz crystal clk - 1: 100MHz ext clk routed through MiPHY1 + * MiPHY1: OSC_FORCE_EXT means: + * 1: 30MHz crystal clk - 0: 100MHz ext clk routed through MiPHY1 + * Some devices have not the possibility to check if the osc is ready. + */ +#define MIPHY_OSC_FORCE_EXT BIT(3) +#define MIPHY_OSC_RDY BIT(5) + +#define MIPHY_CTRL_MASK 0x0f +#define MIPHY_CTRL_DEFAULT 0 +#define MIPHY_CTRL_SYNC_D_EN BIT(2) + +/* SATA / PCIe defines */ +#define SATA_CTRL_MASK 0x07 +#define PCIE_CTRL_MASK 0xff +#define SATA_CTRL_SELECT_SATA 1 +#define SATA_CTRL_SELECT_PCIE 0 +#define SYSCFG_PCIE_PCIE_VAL 0x80 +#define SATA_SPDMODE 1 + +struct miphy28lp_phy { + struct phy *phy; + struct miphy28lp_dev *phydev; + void __iomem *base; + void __iomem *pipebase; + + bool osc_force_ext; + bool osc_rdy; + bool px_rx_pol_inv; + + struct reset_control *miphy_rst; + + u32 sata_gen; + + /* Sysconfig registers offsets needed to configure the device */ + u32 syscfg_miphy_ctrl; + u32 syscfg_miphy_status; + u32 syscfg_pci; + u32 syscfg_sata; + u8 type; +}; + +struct miphy28lp_dev { + struct device *dev; + struct regmap *regmap; + struct mutex miphy_mutex; + struct miphy28lp_phy **phys; +}; + +struct miphy_initval { + u16 reg; + u16 val; +}; + +enum miphy_sata_gen { SATA_GEN1, SATA_GEN2, SATA_GEN3 }; + +static char *PHY_TYPE_name[] = { "sata-up", "pcie-up", "usb3-up" }; + +struct pll_ratio { + int clk_ref; + int calset_1; + int calset_2; + int calset_3; + int calset_4; + int cal_ctrl; +}; + +static struct pll_ratio sata_pll_ratio = { + .clk_ref = 0x1e, + .calset_1 = 0xc8, + .calset_2 = 0x00, + .calset_3 = 0x00, + .calset_4 = 0x00, + .cal_ctrl = 0x00, +}; + +static struct pll_ratio pcie_pll_ratio = { + .clk_ref = 0x1e, + .calset_1 = 0xa6, + .calset_2 = 0xaa, + .calset_3 = 0xaa, + .calset_4 = 0x00, + .cal_ctrl = 0x00, +}; + +static struct pll_ratio usb3_pll_ratio = { + .clk_ref = 0x1e, + .calset_1 = 0xa6, + .calset_2 = 0xaa, + .calset_3 = 0xaa, + .calset_4 = 0x04, + .cal_ctrl = 0x00, +}; + +struct miphy28lp_pll_gen { + int bank; + int speed; + int bias_boost_1; + int bias_boost_2; + int tx_ctrl_1; + int tx_ctrl_2; + int tx_ctrl_3; + int rx_k_gain; + int rx_vga_gain; + int rx_equ_gain_1; + int rx_equ_gain_2; + int rx_equ_gain_3; + int rx_buff_ctrl; +}; + +static struct miphy28lp_pll_gen sata_pll_gen[] = { + { + .bank = 0x00, + .speed = TX_SPDSEL_80DEC | RX_SPDSEL_80DEC, + .bias_boost_1 = 0x00, + .bias_boost_2 = 0xae, + .tx_ctrl_2 = 0x53, + .tx_ctrl_3 = 0x00, + .rx_buff_ctrl = EQ_BOOST_GAIN | EQ_DC_GAIN | VGA_GAIN, + .rx_vga_gain = 0x00, + .rx_equ_gain_1 = 0x7d, + .rx_equ_gain_2 = 0x56, + .rx_equ_gain_3 = 0x00, + }, + { + .bank = 0x01, + .speed = TX_SPDSEL_40DEC | RX_SPDSEL_40DEC, + .bias_boost_1 = 0x00, + .bias_boost_2 = 0xae, + .tx_ctrl_2 = 0x72, + .tx_ctrl_3 = 0x20, + .rx_buff_ctrl = EQ_BOOST_GAIN | EQ_DC_GAIN | VGA_GAIN, + .rx_vga_gain = 0x00, + .rx_equ_gain_1 = 0x7d, + .rx_equ_gain_2 = 0x56, + .rx_equ_gain_3 = 0x00, + }, + { + .bank = 0x02, + .speed = TX_SPDSEL_20DEC | RX_SPDSEL_20DEC, + .bias_boost_1 = 0x00, + .bias_boost_2 = 0xae, + .tx_ctrl_2 = 0xc0, + .tx_ctrl_3 = 0x20, + .rx_buff_ctrl = EQ_BOOST_GAIN | EQ_DC_GAIN | VGA_GAIN, + .rx_vga_gain = 0x00, + .rx_equ_gain_1 = 0x7d, + .rx_equ_gain_2 = 0x56, + .rx_equ_gain_3 = 0x00, + }, +}; + +static struct miphy28lp_pll_gen pcie_pll_gen[] = { + { + .bank = 0x00, + .speed = TX_SPDSEL_40DEC | RX_SPDSEL_40DEC, + .bias_boost_1 = 0x00, + .bias_boost_2 = 0xa5, + .tx_ctrl_1 = TX_REG_STEP_N_25MV, + .tx_ctrl_2 = 0x71, + .tx_ctrl_3 = 0x60, + .rx_k_gain = 0x98, + .rx_buff_ctrl = EQ_BOOST_GAIN | EQ_DC_GAIN | VGA_GAIN, + .rx_vga_gain = 0x00, + .rx_equ_gain_1 = 0x79, + .rx_equ_gain_2 = 0x56, + }, + { + .bank = 0x01, + .speed = TX_SPDSEL_20DEC | RX_SPDSEL_20DEC, + .bias_boost_1 = 0x00, + .bias_boost_2 = 0xa5, + .tx_ctrl_1 = TX_REG_STEP_N_25MV, + .tx_ctrl_2 = 0x70, + .tx_ctrl_3 = 0x60, + .rx_k_gain = 0xcc, + .rx_buff_ctrl = EQ_BOOST_GAIN | EQ_DC_GAIN | VGA_GAIN, + .rx_vga_gain = 0x00, + .rx_equ_gain_1 = 0x78, + .rx_equ_gain_2 = 0x07, + }, +}; + +static inline void miphy28lp_set_reset(struct miphy28lp_phy *miphy_phy) +{ + void *base = miphy_phy->base; + u8 val; + + /* Putting Macro in reset */ + writeb_relaxed(RST_APPLI_SW, base + MIPHY_CONF_RESET); + + val = RST_APPLI_SW | RST_CONF_SW; + writeb_relaxed(val, base + MIPHY_CONF_RESET); + + writeb_relaxed(RST_APPLI_SW, base + MIPHY_CONF_RESET); + + /* Bringing the MIPHY-CPU registers out of reset */ + if (miphy_phy->type == PHY_TYPE_PCIE) { + val = AUTO_RST_RX | TERM_EN_SW; + writeb_relaxed(val, base + MIPHY_CONTROL); + } else { + val = AUTO_RST_RX | TERM_EN_SW | DIS_LINK_RST; + writeb_relaxed(val, base + MIPHY_CONTROL); + } +} + +static inline void miphy28lp_pll_calibration(struct miphy28lp_phy *miphy_phy, + struct pll_ratio *pll_ratio) +{ + void *base = miphy_phy->base; + u8 val; + + /* Applying PLL Settings */ + writeb_relaxed(0x1d, base + MIPHY_PLL_SPAREIN); + writeb_relaxed(pll_ratio->clk_ref, base + MIPHY_PLL_CLKREF_FREQ); + + /* PLL Ratio */ + writeb_relaxed(pll_ratio->calset_1, base + MIPHY_PLL_CALSET_1); + writeb_relaxed(pll_ratio->calset_2, base + MIPHY_PLL_CALSET_2); + writeb_relaxed(pll_ratio->calset_3, base + MIPHY_PLL_CALSET_3); + writeb_relaxed(pll_ratio->calset_4, base + MIPHY_PLL_CALSET_4); + writeb_relaxed(pll_ratio->cal_ctrl, base + MIPHY_PLL_CALSET_CTRL); + + writeb_relaxed(TX_SEL, base + MIPHY_BOUNDARY_SEL); + + val = (0x68 << 1) | TX_SLEW_CAL_MAN_EN; + writeb_relaxed(val, base + MIPHY_TX_CAL_MAN); + + val = VGA_OFFSET_POLARITY | CAL_OFFSET_THRESHOLD_64 | CAL_OFFSET_VGA_64; + + if (miphy_phy->type != PHY_TYPE_SATA) + val |= OFFSET_COMPENSATION_EN; + + writeb_relaxed(val, base + MIPHY_RX_CAL_OFFSET_CTRL); + + if (miphy_phy->type == PHY_TYPE_USB) { + writeb_relaxed(0x00, base + MIPHY_CONF); + writeb_relaxed(0x70, base + MIPHY_RX_LOCK_STEP); + writeb_relaxed(EN_FIRST_HALF, base + MIPHY_RX_SIGDET_SLEEP_OA); + writeb_relaxed(EN_FIRST_HALF, base + MIPHY_RX_SIGDET_SLEEP_SEL); + writeb_relaxed(EN_FIRST_HALF, base + MIPHY_RX_SIGDET_WAIT_SEL); + + val = EN_DIGIT_SIGNAL_CHECK | EN_FIRST_HALF; + writeb_relaxed(val, base + MIPHY_RX_SIGDET_DATA_SEL); + } + +} + +static inline void miphy28lp_sata_config_gen(struct miphy28lp_phy *miphy_phy) +{ + void __iomem *base = miphy_phy->base; + int i; + + for (i = 0; i < ARRAY_SIZE(sata_pll_gen); i++) { + struct miphy28lp_pll_gen *gen = &sata_pll_gen[i]; + + /* Banked settings */ + writeb_relaxed(gen->bank, base + MIPHY_CONF); + writeb_relaxed(gen->speed, base + MIPHY_SPEED); + writeb_relaxed(gen->bias_boost_1, base + MIPHY_BIAS_BOOST_1); + writeb_relaxed(gen->bias_boost_2, base + MIPHY_BIAS_BOOST_2); + + /* TX buffer Settings */ + writeb_relaxed(gen->tx_ctrl_2, base + MIPHY_TX_CTRL_2); + writeb_relaxed(gen->tx_ctrl_3, base + MIPHY_TX_CTRL_3); + + /* RX Buffer Settings */ + writeb_relaxed(gen->rx_buff_ctrl, base + MIPHY_RX_BUFFER_CTRL); + writeb_relaxed(gen->rx_vga_gain, base + MIPHY_RX_VGA_GAIN); + writeb_relaxed(gen->rx_equ_gain_1, base + MIPHY_RX_EQU_GAIN_1); + writeb_relaxed(gen->rx_equ_gain_2, base + MIPHY_RX_EQU_GAIN_2); + writeb_relaxed(gen->rx_equ_gain_3, base + MIPHY_RX_EQU_GAIN_3); + } +} + +static inline void miphy28lp_pcie_config_gen(struct miphy28lp_phy *miphy_phy) +{ + void __iomem *base = miphy_phy->base; + int i; + + for (i = 0; i < ARRAY_SIZE(pcie_pll_gen); i++) { + struct miphy28lp_pll_gen *gen = &pcie_pll_gen[i]; + + /* Banked settings */ + writeb_relaxed(gen->bank, base + MIPHY_CONF); + writeb_relaxed(gen->speed, base + MIPHY_SPEED); + writeb_relaxed(gen->bias_boost_1, base + MIPHY_BIAS_BOOST_1); + writeb_relaxed(gen->bias_boost_2, base + MIPHY_BIAS_BOOST_2); + + /* TX buffer Settings */ + writeb_relaxed(gen->tx_ctrl_1, base + MIPHY_TX_CTRL_1); + writeb_relaxed(gen->tx_ctrl_2, base + MIPHY_TX_CTRL_2); + writeb_relaxed(gen->tx_ctrl_3, base + MIPHY_TX_CTRL_3); + + writeb_relaxed(gen->rx_k_gain, base + MIPHY_RX_K_GAIN); + + /* RX Buffer Settings */ + writeb_relaxed(gen->rx_buff_ctrl, base + MIPHY_RX_BUFFER_CTRL); + writeb_relaxed(gen->rx_vga_gain, base + MIPHY_RX_VGA_GAIN); + writeb_relaxed(gen->rx_equ_gain_1, base + MIPHY_RX_EQU_GAIN_1); + writeb_relaxed(gen->rx_equ_gain_2, base + MIPHY_RX_EQU_GAIN_2); + } +} + +static inline int miphy28lp_wait_compensation(struct miphy28lp_phy *miphy_phy) +{ + unsigned long finish = jiffies + 5 * HZ; + u8 val; + + /* Waiting for Compensation to complete */ + do { + val = readb_relaxed(miphy_phy->base + MIPHY_COMP_FSM_6); + + if (time_after_eq(jiffies, finish)) + return -EBUSY; + cpu_relax(); + } while (!(val & COMP_DONE)); + + return 0; +} + + +static inline int miphy28lp_compensation(struct miphy28lp_phy *miphy_phy, + struct pll_ratio *pll_ratio) +{ + void __iomem *base = miphy_phy->base; + + /* Poll for HFC ready after reset release */ + /* Compensation measurement */ + writeb_relaxed(RST_PLL_SW | RST_COMP_SW, base + MIPHY_RESET); + + writeb_relaxed(0x00, base + MIPHY_PLL_COMMON_MISC_2); + writeb_relaxed(pll_ratio->clk_ref, base + MIPHY_PLL_CLKREF_FREQ); + writeb_relaxed(COMP_START, base + MIPHY_COMP_FSM_1); + + if (miphy_phy->type == PHY_TYPE_PCIE) + writeb_relaxed(RST_PLL_SW, base + MIPHY_RESET); + + writeb_relaxed(0x00, base + MIPHY_RESET); + writeb_relaxed(START_ACT_FILT, base + MIPHY_PLL_COMMON_MISC_2); + writeb_relaxed(SET_NEW_CHANGE, base + MIPHY_PLL_SBR_1); + + /* TX compensation offset to re-center TX impedance */ + writeb_relaxed(0x00, base + MIPHY_COMP_POSTP); + + if (miphy_phy->type == PHY_TYPE_PCIE) + return miphy28lp_wait_compensation(miphy_phy); + + return 0; +} + +static inline void miphy28_usb3_miphy_reset(struct miphy28lp_phy *miphy_phy) +{ + void __iomem *base = miphy_phy->base; + u8 val; + + /* MIPHY Reset */ + writeb_relaxed(RST_APPLI_SW, base + MIPHY_CONF_RESET); + writeb_relaxed(0x00, base + MIPHY_CONF_RESET); + writeb_relaxed(RST_COMP_SW, base + MIPHY_RESET); + + val = RST_COMP_SW | RST_PLL_SW; + writeb_relaxed(val, base + MIPHY_RESET); + + writeb_relaxed(0x00, base + MIPHY_PLL_COMMON_MISC_2); + writeb_relaxed(0x1e, base + MIPHY_PLL_CLKREF_FREQ); + writeb_relaxed(COMP_START, base + MIPHY_COMP_FSM_1); + writeb_relaxed(RST_PLL_SW, base + MIPHY_RESET); + writeb_relaxed(0x00, base + MIPHY_RESET); + writeb_relaxed(START_ACT_FILT, base + MIPHY_PLL_COMMON_MISC_2); + writeb_relaxed(0x00, base + MIPHY_CONF); + writeb_relaxed(0x00, base + MIPHY_BOUNDARY_1); + writeb_relaxed(0x00, base + MIPHY_TST_BIAS_BOOST_2); + writeb_relaxed(0x00, base + MIPHY_CONF); + writeb_relaxed(SET_NEW_CHANGE, base + MIPHY_PLL_SBR_1); + writeb_relaxed(0xa5, base + MIPHY_DEBUG_BUS); + writeb_relaxed(0x00, base + MIPHY_CONF); +} + +static inline int miphy28lp_configure_sata(struct miphy28lp_phy *miphy_phy) +{ + void __iomem *base = miphy_phy->base; + int err; + u8 val; + + /* Putting Macro in reset */ + miphy28lp_set_reset(miphy_phy); + + /* PLL calibration */ + miphy28lp_pll_calibration(miphy_phy, &sata_pll_ratio); + + /* Banked settings Gen1/Gen2/Gen3 */ + miphy28lp_sata_config_gen(miphy_phy); + + /* Power control */ + /* Input bridge enable, manual input bridge control */ + writeb_relaxed(0x21, base + MIPHY_RX_POWER_CTRL_1); + + /* Macro out of reset */ + writeb_relaxed(0x00, base + MIPHY_CONF_RESET); + + /* Poll for HFC ready after reset release */ + /* Compensation measurement */ + err = miphy28lp_compensation(miphy_phy, &sata_pll_ratio); + if (err) + return err; + + if (miphy_phy->px_rx_pol_inv) { + /* Invert Rx polarity */ + val = readb_relaxed(miphy_phy->base + MIPHY_CONTROL); + val |= PX_RX_POL; + writeb_relaxed(val, miphy_phy->base + MIPHY_CONTROL); + } + + return 0; +} + +static inline int miphy28lp_configure_pcie(struct miphy28lp_phy *miphy_phy) +{ + void __iomem *base = miphy_phy->base; + int err; + + /* Putting Macro in reset */ + miphy28lp_set_reset(miphy_phy); + + /* PLL calibration */ + miphy28lp_pll_calibration(miphy_phy, &pcie_pll_ratio); + + /* Banked settings Gen1/Gen2 */ + miphy28lp_pcie_config_gen(miphy_phy); + + /* Power control */ + /* Input bridge enable, manual input bridge control */ + writeb_relaxed(0x21, base + MIPHY_RX_POWER_CTRL_1); + + /* Macro out of reset */ + writeb_relaxed(0x00, base + MIPHY_CONF_RESET); + + /* Poll for HFC ready after reset release */ + /* Compensation measurement */ + err = miphy28lp_compensation(miphy_phy, &pcie_pll_ratio); + if (err) + return err; + + return 0; +} + + +static inline void miphy28lp_configure_usb3(struct miphy28lp_phy *miphy_phy) +{ + void __iomem *base = miphy_phy->base; + u8 val; + + /* Putting Macro in reset */ + miphy28lp_set_reset(miphy_phy); + + /* PLL calibration */ + miphy28lp_pll_calibration(miphy_phy, &usb3_pll_ratio); + + /* Writing The Speed Rate */ + writeb_relaxed(0x00, base + MIPHY_CONF); + + val = RX_SPDSEL_20DEC | TX_SPDSEL_20DEC; + writeb_relaxed(val, base + MIPHY_SPEED); + + /* RX Channel compensation and calibration */ + writeb_relaxed(0x1c, base + MIPHY_RX_LOCK_SETTINGS_OPT); + writeb_relaxed(0x51, base + MIPHY_RX_CAL_CTRL_1); + writeb_relaxed(0x70, base + MIPHY_RX_CAL_CTRL_2); + + val = OFFSET_COMPENSATION_EN | VGA_OFFSET_POLARITY | + CAL_OFFSET_THRESHOLD_64 | CAL_OFFSET_VGA_64; + writeb_relaxed(val, base + MIPHY_RX_CAL_OFFSET_CTRL); + writeb_relaxed(0x22, base + MIPHY_RX_CAL_VGA_STEP); + writeb_relaxed(0x0e, base + MIPHY_RX_CAL_OPT_LENGTH); + + val = EQ_DC_GAIN | VGA_GAIN; + writeb_relaxed(val, base + MIPHY_RX_BUFFER_CTRL); + writeb_relaxed(0x78, base + MIPHY_RX_EQU_GAIN_1); + writeb_relaxed(0x1b, base + MIPHY_SYNCHAR_CONTROL); + + /* TX compensation offset to re-center TX impedance */ + writeb_relaxed(0x02, base + MIPHY_COMP_POSTP); + + /* Enable GENSEL_SEL and SSC */ + /* TX_SEL=0 swing preemp forced by pipe registres */ + val = SSC_SEL | GENSEL_SEL; + writeb_relaxed(val, base + MIPHY_BOUNDARY_SEL); + + /* MIPHY Bias boost */ + writeb_relaxed(0x00, base + MIPHY_BIAS_BOOST_1); + writeb_relaxed(0xa7, base + MIPHY_BIAS_BOOST_2); + + /* SSC modulation */ + writeb_relaxed(SSC_EN_SW, base + MIPHY_BOUNDARY_2); + + /* MIPHY TX control */ + writeb_relaxed(0x00, base + MIPHY_CONF); + + /* Validate Step component */ + writeb_relaxed(0x5a, base + MIPHY_PLL_SBR_3); + writeb_relaxed(0xa0, base + MIPHY_PLL_SBR_4); + + /* Validate Period component */ + writeb_relaxed(0x3c, base + MIPHY_PLL_SBR_2); + writeb_relaxed(0xa1, base + MIPHY_PLL_SBR_4); + + /* Clear any previous request */ + writeb_relaxed(0x00, base + MIPHY_PLL_SBR_1); + + /* requests the PLL to take in account new parameters */ + writeb_relaxed(0x02, base + MIPHY_PLL_SBR_1); + + /* To be sure there is no other pending requests */ + writeb_relaxed(0x00, base + MIPHY_PLL_SBR_1); + + /* Rx PI controller settings */ + writeb_relaxed(0xca, base + MIPHY_RX_K_GAIN); + + /* MIPHY RX input bridge control */ + /* INPUT_BRIDGE_EN_SW=1, manual input bridge control[0]=1 */ + writeb_relaxed(0x21, base + MIPHY_RX_POWER_CTRL_1); + writeb_relaxed(0x29, base + MIPHY_RX_POWER_CTRL_1); + writeb_relaxed(0x1a, base + MIPHY_RX_POWER_CTRL_2); + + /* MIPHY Reset for usb3 */ + miphy28_usb3_miphy_reset(miphy_phy); +} + +static inline int miphy_is_ready(struct miphy28lp_phy *miphy_phy) +{ + unsigned long finish = jiffies + 5 * HZ; + u8 mask = HFC_PLL | HFC_RDY; + u8 val; + + /* + * For PCIe and USB3 check only that PLL and HFC are ready + * For SATA check also that phy is ready! + */ + if (miphy_phy->type == PHY_TYPE_SATA) + mask |= PHY_RDY; + + do { + val = readb_relaxed(miphy_phy->base + MIPHY_STATUS_1); + if ((val & mask) != mask) + cpu_relax(); + else + return 0; + } while (!time_after_eq(jiffies, finish)); + + return -EBUSY; +} + +static int miphy_osc_is_ready(struct miphy28lp_phy *miphy_phy) +{ + struct miphy28lp_dev *miphy_dev = miphy_phy->phydev; + unsigned long finish = jiffies + 5 * HZ; + u32 val; + + if (!miphy_phy->osc_rdy) + return 0; + + if (!miphy_phy->syscfg_miphy_status) + return -EINVAL; + + do { + regmap_read(miphy_dev->regmap, miphy_phy->syscfg_miphy_status, + &val); + + if ((val & MIPHY_OSC_RDY) != MIPHY_OSC_RDY) + cpu_relax(); + else + return 0; + } while (!time_after_eq(jiffies, finish)); + + return -EBUSY; +} + +static int miphy28lp_get_resource_byname(struct device_node *child, + char *rname, struct resource *res) +{ + int index; + + index = of_property_match_string(child, "reg-names", rname); + if (index < 0) + return -ENODEV; + + return of_address_to_resource(child, index, res); +} + +static int miphy28lp_get_one_addr(struct device *dev, + struct device_node *child, char *rname, + void __iomem **base) +{ + struct resource res; + int ret; + + ret = miphy28lp_get_resource_byname(child, rname, &res); + if (!ret) { + *base = devm_ioremap(dev, res.start, resource_size(&res)); + if (!*base) { + dev_err(dev, "failed to ioremap %s address region\n" + , rname); + return -ENOENT; + } + } + + return 0; +} + +/* MiPHY reset and sysconf setup */ +static int miphy28lp_setup(struct miphy28lp_phy *miphy_phy, u32 miphy_val) +{ + int err; + struct miphy28lp_dev *miphy_dev = miphy_phy->phydev; + + if (!miphy_phy->syscfg_miphy_ctrl) + return -EINVAL; + + err = reset_control_assert(miphy_phy->miphy_rst); + if (err) { + dev_err(miphy_dev->dev, "unable to bring out of miphy reset\n"); + return err; + } + + if (miphy_phy->osc_force_ext) + miphy_val |= MIPHY_OSC_FORCE_EXT; + + regmap_update_bits(miphy_dev->regmap, miphy_phy->syscfg_miphy_ctrl, + MIPHY_CTRL_MASK, miphy_val); + + err = reset_control_deassert(miphy_phy->miphy_rst); + if (err) { + dev_err(miphy_dev->dev, "unable to bring out of miphy reset\n"); + return err; + } + + return miphy_osc_is_ready(miphy_phy); +} + +static int miphy28lp_init_sata(struct miphy28lp_phy *miphy_phy) +{ + struct miphy28lp_dev *miphy_dev = miphy_phy->phydev; + int err, sata_conf = SATA_CTRL_SELECT_SATA; + + if ((!miphy_phy->syscfg_sata) || (!miphy_phy->syscfg_pci) + || (!miphy_phy->base)) + return -EINVAL; + + dev_info(miphy_dev->dev, "sata-up mode, addr 0x%p\n", miphy_phy->base); + + /* Configure the glue-logic */ + sata_conf |= ((miphy_phy->sata_gen - SATA_GEN1) << SATA_SPDMODE); + + regmap_update_bits(miphy_dev->regmap, miphy_phy->syscfg_sata, + SATA_CTRL_MASK, sata_conf); + + regmap_update_bits(miphy_dev->regmap, miphy_phy->syscfg_pci, + PCIE_CTRL_MASK, SATA_CTRL_SELECT_PCIE); + + /* MiPHY path and clocking init */ + err = miphy28lp_setup(miphy_phy, MIPHY_CTRL_DEFAULT); + + if (err) { + dev_err(miphy_dev->dev, "SATA phy setup failed\n"); + return err; + } + + /* initialize miphy */ + miphy28lp_configure_sata(miphy_phy); + + return miphy_is_ready(miphy_phy); +} + +static int miphy28lp_init_pcie(struct miphy28lp_phy *miphy_phy) +{ + struct miphy28lp_dev *miphy_dev = miphy_phy->phydev; + int err; + + if ((!miphy_phy->syscfg_sata) || (!miphy_phy->syscfg_pci) + || (!miphy_phy->base) || (!miphy_phy->pipebase)) + return -EINVAL; + + dev_info(miphy_dev->dev, "pcie-up mode, addr 0x%p\n", miphy_phy->base); + + /* Configure the glue-logic */ + regmap_update_bits(miphy_dev->regmap, miphy_phy->syscfg_sata, + SATA_CTRL_MASK, SATA_CTRL_SELECT_PCIE); + + regmap_update_bits(miphy_dev->regmap, miphy_phy->syscfg_pci, + PCIE_CTRL_MASK, SYSCFG_PCIE_PCIE_VAL); + + /* MiPHY path and clocking init */ + err = miphy28lp_setup(miphy_phy, MIPHY_CTRL_DEFAULT); + + if (err) { + dev_err(miphy_dev->dev, "PCIe phy setup failed\n"); + return err; + } + + /* initialize miphy */ + err = miphy28lp_configure_pcie(miphy_phy); + if (err) + return err; + + /* PIPE Wrapper Configuration */ + writeb_relaxed(0x68, miphy_phy->pipebase + 0x104); /* Rise_0 */ + writeb_relaxed(0x61, miphy_phy->pipebase + 0x105); /* Rise_1 */ + writeb_relaxed(0x68, miphy_phy->pipebase + 0x108); /* Fall_0 */ + writeb_relaxed(0x61, miphy_phy->pipebase + 0x109); /* Fall-1 */ + writeb_relaxed(0x68, miphy_phy->pipebase + 0x10c); /* Threshold_0 */ + writeb_relaxed(0x60, miphy_phy->pipebase + 0x10d); /* Threshold_1 */ + + /* Wait for phy_ready */ + return miphy_is_ready(miphy_phy); +} + +static int miphy28lp_init_usb3(struct miphy28lp_phy *miphy_phy) +{ + struct miphy28lp_dev *miphy_dev = miphy_phy->phydev; + int err; + + if ((!miphy_phy->base) || (!miphy_phy->pipebase)) + return -EINVAL; + + dev_info(miphy_dev->dev, "usb3-up mode, addr 0x%p\n", miphy_phy->base); + + /* MiPHY path and clocking init */ + err = miphy28lp_setup(miphy_phy, MIPHY_CTRL_SYNC_D_EN); + if (err) { + dev_err(miphy_dev->dev, "USB3 phy setup failed\n"); + return err; + } + + /* initialize miphy */ + miphy28lp_configure_usb3(miphy_phy); + + /* PIPE Wrapper Configuration */ + writeb_relaxed(0x68, miphy_phy->pipebase + 0x23); + writeb_relaxed(0x61, miphy_phy->pipebase + 0x24); + writeb_relaxed(0x68, miphy_phy->pipebase + 0x26); + writeb_relaxed(0x61, miphy_phy->pipebase + 0x27); + writeb_relaxed(0x18, miphy_phy->pipebase + 0x29); + writeb_relaxed(0x61, miphy_phy->pipebase + 0x2a); + + /* pipe Wrapper usb3 TX swing de-emph margin PREEMPH[7:4], SWING[3:0] */ + writeb_relaxed(0X67, miphy_phy->pipebase + 0x68); + writeb_relaxed(0x0d, miphy_phy->pipebase + 0x69); + writeb_relaxed(0X67, miphy_phy->pipebase + 0x6a); + writeb_relaxed(0X0d, miphy_phy->pipebase + 0x6b); + writeb_relaxed(0X67, miphy_phy->pipebase + 0x6c); + writeb_relaxed(0X0d, miphy_phy->pipebase + 0x6d); + writeb_relaxed(0X67, miphy_phy->pipebase + 0x6e); + writeb_relaxed(0X0d, miphy_phy->pipebase + 0x6f); + + return miphy_is_ready(miphy_phy); +} + +static int miphy28lp_init(struct phy *phy) +{ + struct miphy28lp_phy *miphy_phy = phy_get_drvdata(phy); + struct miphy28lp_dev *miphy_dev = miphy_phy->phydev; + int ret; + + mutex_lock(&miphy_dev->miphy_mutex); + + switch (miphy_phy->type) { + + case PHY_TYPE_SATA: + ret = miphy28lp_init_sata(miphy_phy); + break; + case PHY_TYPE_PCIE: + ret = miphy28lp_init_pcie(miphy_phy); + break; + case PHY_TYPE_USB: + ret = miphy28lp_init_usb3(miphy_phy); + break; + default: + return -EINVAL; + } + + mutex_unlock(&miphy_dev->miphy_mutex); + + return ret; +} + +static int miphy28lp_get_addr(struct miphy28lp_phy *miphy_phy) +{ + struct miphy28lp_dev *miphy_dev = miphy_phy->phydev; + struct device_node *phynode = miphy_phy->phy->dev.of_node; + int err; + + if (!miphy_phy->type || (miphy_phy->type > PHY_TYPE_USB)) + return -EINVAL; + + err = miphy28lp_get_one_addr(miphy_dev->dev, phynode, + PHY_TYPE_name[miphy_phy->type - PHY_TYPE_SATA], + &miphy_phy->base); + if (err) + return err; + + if ((miphy_phy->type == PHY_TYPE_PCIE) || + (miphy_phy->type == PHY_TYPE_USB)) { + err = miphy28lp_get_one_addr(miphy_dev->dev, phynode, "pipew", + &miphy_phy->pipebase); + if (err) + return err; + } + + return 0; +} + +static struct phy *miphy28lp_xlate(struct device *dev, + struct of_phandle_args *args) +{ + struct miphy28lp_dev *miphy_dev = dev_get_drvdata(dev); + struct miphy28lp_phy *miphy_phy = NULL; + struct device_node *phynode = args->np; + int ret, index = 0; + + if (!of_device_is_available(phynode)) { + dev_warn(dev, "Requested PHY is disabled\n"); + return ERR_PTR(-ENODEV); + } + + if (args->args_count != 1) { + dev_err(dev, "Invalid number of cells in 'phy' property\n"); + return ERR_PTR(-EINVAL); + } + + for (index = 0; index < of_get_child_count(dev->of_node); index++) + if (phynode == miphy_dev->phys[index]->phy->dev.of_node) { + miphy_phy = miphy_dev->phys[index]; + break; + } + + if (!miphy_phy) { + dev_err(dev, "Failed to find appropriate phy\n"); + return ERR_PTR(-EINVAL); + } + + miphy_phy->type = args->args[0]; + + ret = miphy28lp_get_addr(miphy_phy); + if (ret < 0) + return ERR_PTR(ret); + + return miphy_phy->phy; +} + +static struct phy_ops miphy28lp_ops = { + .init = miphy28lp_init, +}; + +static int miphy28lp_probe_resets(struct device_node *node, + struct miphy28lp_phy *miphy_phy) +{ + struct miphy28lp_dev *miphy_dev = miphy_phy->phydev; + int err; + + miphy_phy->miphy_rst = of_reset_control_get(node, "miphy-sw-rst"); + + if (IS_ERR(miphy_phy->miphy_rst)) { + dev_err(miphy_dev->dev, + "miphy soft reset control not defined\n"); + return PTR_ERR(miphy_phy->miphy_rst); + } + + err = reset_control_deassert(miphy_phy->miphy_rst); + if (err) { + dev_err(miphy_dev->dev, "unable to bring out of miphy reset\n"); + return err; + } + + return 0; +} + +static int miphy28lp_of_probe(struct device_node *np, + struct miphy28lp_phy *miphy_phy) +{ + struct resource res; + + miphy_phy->osc_force_ext = + of_property_read_bool(np, "st,osc-force-ext"); + + miphy_phy->osc_rdy = of_property_read_bool(np, "st,osc-rdy"); + + miphy_phy->px_rx_pol_inv = + of_property_read_bool(np, "st,px_rx_pol_inv"); + + of_property_read_u32(np, "st,sata-gen", &miphy_phy->sata_gen); + if (!miphy_phy->sata_gen) + miphy_phy->sata_gen = SATA_GEN1; + + if (!miphy28lp_get_resource_byname(np, "miphy-ctrl-glue", &res)) + miphy_phy->syscfg_miphy_ctrl = res.start; + + if (!miphy28lp_get_resource_byname(np, "miphy-status-glue", &res)) + miphy_phy->syscfg_miphy_status = res.start; + + if (!miphy28lp_get_resource_byname(np, "pcie-glue", &res)) + miphy_phy->syscfg_pci = res.start; + + if (!miphy28lp_get_resource_byname(np, "sata-glue", &res)) + miphy_phy->syscfg_sata = res.start; + + + return 0; +} + +static int miphy28lp_probe(struct platform_device *pdev) +{ + struct device_node *child, *np = pdev->dev.of_node; + struct miphy28lp_dev *miphy_dev; + struct phy_provider *provider; + struct phy *phy; + int chancount, port = 0; + int ret; + + miphy_dev = devm_kzalloc(&pdev->dev, sizeof(*miphy_dev), GFP_KERNEL); + if (!miphy_dev) + return -ENOMEM; + + chancount = of_get_child_count(np); + miphy_dev->phys = devm_kzalloc(&pdev->dev, sizeof(phy) * chancount, + GFP_KERNEL); + if (!miphy_dev->phys) + return -ENOMEM; + + miphy_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg"); + if (IS_ERR(miphy_dev->regmap)) { + dev_err(miphy_dev->dev, "No syscfg phandle specified\n"); + return PTR_ERR(miphy_dev->regmap); + } + + miphy_dev->dev = &pdev->dev; + + dev_set_drvdata(&pdev->dev, miphy_dev); + + mutex_init(&miphy_dev->miphy_mutex); + + for_each_child_of_node(np, child) { + struct miphy28lp_phy *miphy_phy; + + miphy_phy = devm_kzalloc(&pdev->dev, sizeof(*miphy_phy), + GFP_KERNEL); + if (!miphy_phy) + return -ENOMEM; + + miphy_dev->phys[port] = miphy_phy; + + phy = devm_phy_create(&pdev->dev, child, &miphy28lp_ops, NULL); + if (IS_ERR(phy)) { + dev_err(&pdev->dev, "failed to create PHY\n"); + return PTR_ERR(phy); + } + + miphy_dev->phys[port]->phy = phy; + miphy_dev->phys[port]->phydev = miphy_dev; + + ret = miphy28lp_of_probe(child, miphy_phy); + if (ret) + return ret; + + ret = miphy28lp_probe_resets(child, miphy_dev->phys[port]); + if (ret) + return ret; + + phy_set_drvdata(phy, miphy_dev->phys[port]); + port++; + + } + + provider = devm_of_phy_provider_register(&pdev->dev, miphy28lp_xlate); + if (IS_ERR(provider)) + return PTR_ERR(provider); + + return 0; +} + +static const struct of_device_id miphy28lp_of_match[] = { + {.compatible = "st,miphy28lp-phy", }, + {}, +}; + +MODULE_DEVICE_TABLE(of, miphy28lp_of_match); + +static struct platform_driver miphy28lp_driver = { + .probe = miphy28lp_probe, + .driver = { + .name = "miphy28lp-phy", + .owner = THIS_MODULE, + .of_match_table = miphy28lp_of_match, + } +}; + +module_platform_driver(miphy28lp_driver); + +MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue@xxxxxx>"); +MODULE_DESCRIPTION("STMicroelectronics miphy28lp driver"); +MODULE_LICENSE("GPL v2"); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html