From 7fff5d958648eadec1b164dc5a61a5644117d329 Mon Sep 17 00:00:00 2001 From: Dimitri Fedrau Date: Fri, 14 Feb 2025 15:14:09 +0100 Subject: [PATCH 1/3] dt-bindings: net: ethernet-phy: add property tx-amplitude-100base-tx-percent Add property tx-amplitude-100base-tx-percent in the device tree bindings for configuring the tx amplitude of 100BASE-TX PHYs. Modifying it can be necessary to compensate losses on the PCB and connector, so the voltages measured on the RJ45 pins are conforming. Acked-by: Conor Dooley Signed-off-by: Dimitri Fedrau Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/20250214-dp83822-tx-swing-v5-1-02ca72620599@liebherr.com Signed-off-by: Jakub Kicinski --- Documentation/devicetree/bindings/net/ethernet-phy.yaml | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml index 2c71454ae8e36..824bbe4333b7e 100644 --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml @@ -232,6 +232,12 @@ properties: PHY's that have configurable TX internal delays. If this property is present then the PHY applies the TX delay. + tx-amplitude-100base-tx-percent: + description: + Transmit amplitude gain applied for 100BASE-TX. 100% matches 2V + peak-to-peak specified in ANSI X3.263. When omitted, the PHYs default + will be left as is. + leds: type: object From 961ee5aeea048aa292f28d61f3a96a48554e91af Mon Sep 17 00:00:00 2001 From: Dimitri Fedrau Date: Fri, 14 Feb 2025 15:14:10 +0100 Subject: [PATCH 2/3] net: phy: Add helper for getting tx amplitude gain Add helper which returns the tx amplitude gain defined in device tree. Modifying it can be necessary to compensate losses on the PCB and connector, so the voltages measured on the RJ45 pins are conforming. Signed-off-by: Dimitri Fedrau Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/20250214-dp83822-tx-swing-v5-2-02ca72620599@liebherr.com Signed-off-by: Jakub Kicinski --- drivers/net/phy/phy_device.c | 53 ++++++++++++++++++++++++------------ include/linux/phy.h | 4 +++ 2 files changed, 39 insertions(+), 18 deletions(-) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 35ec99b4dc510..0d56e7c7f98cd 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -3096,19 +3096,12 @@ void phy_get_pause(struct phy_device *phydev, bool *tx_pause, bool *rx_pause) EXPORT_SYMBOL(phy_get_pause); #if IS_ENABLED(CONFIG_OF_MDIO) -static int phy_get_int_delay_property(struct device *dev, const char *name) +static int phy_get_u32_property(struct device *dev, const char *name, u32 *val) { - s32 int_delay; - int ret; - - ret = device_property_read_u32(dev, name, &int_delay); - if (ret) - return ret; - - return int_delay; + return device_property_read_u32(dev, name, val); } #else -static int phy_get_int_delay_property(struct device *dev, const char *name) +static int phy_get_u32_property(struct device *dev, const char *name, u32 *val) { return -EINVAL; } @@ -3133,12 +3126,12 @@ static int phy_get_int_delay_property(struct device *dev, const char *name) s32 phy_get_internal_delay(struct phy_device *phydev, struct device *dev, const int *delay_values, int size, bool is_rx) { - s32 delay; - int i; + int i, ret; + u32 delay; if (is_rx) { - delay = phy_get_int_delay_property(dev, "rx-internal-delay-ps"); - if (delay < 0 && size == 0) { + ret = phy_get_u32_property(dev, "rx-internal-delay-ps", &delay); + if (ret < 0 && size == 0) { if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID || phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID) return 1; @@ -3147,8 +3140,8 @@ s32 phy_get_internal_delay(struct phy_device *phydev, struct device *dev, } } else { - delay = phy_get_int_delay_property(dev, "tx-internal-delay-ps"); - if (delay < 0 && size == 0) { + ret = phy_get_u32_property(dev, "tx-internal-delay-ps", &delay); + if (ret < 0 && size == 0) { if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID || phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID) return 1; @@ -3157,8 +3150,8 @@ s32 phy_get_internal_delay(struct phy_device *phydev, struct device *dev, } } - if (delay < 0) - return delay; + if (ret < 0) + return ret; if (size == 0) return delay; @@ -3193,6 +3186,30 @@ s32 phy_get_internal_delay(struct phy_device *phydev, struct device *dev, } EXPORT_SYMBOL(phy_get_internal_delay); +/** + * phy_get_tx_amplitude_gain - stores tx amplitude gain in @val + * @phydev: phy_device struct + * @dev: pointer to the devices device struct + * @linkmode: linkmode for which the tx amplitude gain should be retrieved + * @val: tx amplitude gain + * + * Returns: 0 on success, < 0 on failure + */ +int phy_get_tx_amplitude_gain(struct phy_device *phydev, struct device *dev, + enum ethtool_link_mode_bit_indices linkmode, + u32 *val) +{ + switch (linkmode) { + case ETHTOOL_LINK_MODE_100baseT_Full_BIT: + return phy_get_u32_property(dev, + "tx-amplitude-100base-tx-percent", + val); + default: + return -EINVAL; + } +} +EXPORT_SYMBOL_GPL(phy_get_tx_amplitude_gain); + static int phy_led_set_brightness(struct led_classdev *led_cdev, enum led_brightness value) { diff --git a/include/linux/phy.h b/include/linux/phy.h index 3665cdd610a3d..70c632799082e 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -2097,6 +2097,10 @@ void phy_get_pause(struct phy_device *phydev, bool *tx_pause, bool *rx_pause); s32 phy_get_internal_delay(struct phy_device *phydev, struct device *dev, const int *delay_values, int size, bool is_rx); +int phy_get_tx_amplitude_gain(struct phy_device *phydev, struct device *dev, + enum ethtool_link_mode_bit_indices linkmode, + u32 *val); + void phy_resolve_pause(unsigned long *local_adv, unsigned long *partner_adv, bool *tx_pause, bool *rx_pause); From 4f3735e82d8a2e80ee39731832536b1e34697c71 Mon Sep 17 00:00:00 2001 From: Dimitri Fedrau Date: Fri, 14 Feb 2025 15:14:11 +0100 Subject: [PATCH 3/3] net: phy: dp83822: Add support for changing the transmit amplitude voltage Add support for changing the transmit amplitude voltage in 100BASE-TX mode. Modifying it can be necessary to compensate losses on the PCB and connector, so the voltages measured on the RJ45 pins are conforming. Signed-off-by: Dimitri Fedrau Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/20250214-dp83822-tx-swing-v5-3-02ca72620599@liebherr.com Signed-off-by: Jakub Kicinski --- drivers/net/phy/dp83822.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/drivers/net/phy/dp83822.c b/drivers/net/phy/dp83822.c index 6599feca1967d..3662f3905d5ad 100644 --- a/drivers/net/phy/dp83822.c +++ b/drivers/net/phy/dp83822.c @@ -31,6 +31,7 @@ #define MII_DP83822_RCSR 0x17 #define MII_DP83822_RESET_CTRL 0x1f #define MII_DP83822_MLEDCR 0x25 +#define MII_DP83822_LDCTRL 0x403 #define MII_DP83822_LEDCFG1 0x460 #define MII_DP83822_IOCTRL1 0x462 #define MII_DP83822_IOCTRL2 0x463 @@ -123,6 +124,9 @@ #define DP83822_IOCTRL1_GPIO1_CTRL GENMASK(2, 0) #define DP83822_IOCTRL1_GPIO1_CTRL_LED_1 BIT(0) +/* LDCTRL bits */ +#define DP83822_100BASE_TX_LINE_DRIVER_SWING GENMASK(7, 4) + /* IOCTRL2 bits */ #define DP83822_IOCTRL2_GPIO2_CLK_SRC GENMASK(6, 4) #define DP83822_IOCTRL2_GPIO2_CTRL GENMASK(2, 0) @@ -197,6 +201,7 @@ struct dp83822_private { bool set_gpio2_clk_out; u32 gpio2_clk_out; bool led_pin_enable[DP83822_MAX_LED_PINS]; + int tx_amplitude_100base_tx_index; }; static int dp83822_config_wol(struct phy_device *phydev, @@ -522,6 +527,12 @@ static int dp83822_config_init(struct phy_device *phydev) FIELD_PREP(DP83822_IOCTRL2_GPIO2_CLK_SRC, dp83822->gpio2_clk_out)); + if (dp83822->tx_amplitude_100base_tx_index >= 0) + phy_modify_mmd(phydev, MDIO_MMD_VEND2, MII_DP83822_LDCTRL, + DP83822_100BASE_TX_LINE_DRIVER_SWING, + FIELD_PREP(DP83822_100BASE_TX_LINE_DRIVER_SWING, + dp83822->tx_amplitude_100base_tx_index)); + err = dp83822_config_init_leds(phydev); if (err) return err; @@ -720,6 +731,11 @@ static int dp83822_phy_reset(struct phy_device *phydev) } #ifdef CONFIG_OF_MDIO +static const u32 tx_amplitude_100base_tx_gain[] = { + 80, 82, 83, 85, 87, 88, 90, 92, + 93, 95, 97, 98, 100, 102, 103, 105, +}; + static int dp83822_of_init_leds(struct phy_device *phydev) { struct device_node *node = phydev->mdio.dev.of_node; @@ -780,6 +796,8 @@ static int dp83822_of_init(struct phy_device *phydev) struct dp83822_private *dp83822 = phydev->priv; struct device *dev = &phydev->mdio.dev; const char *of_val; + int i, ret; + u32 val; /* Signal detection for the PHY is only enabled if the FX_EN and the * SD_EN pins are strapped. Signal detection can only enabled if FX_EN @@ -815,6 +833,26 @@ static int dp83822_of_init(struct phy_device *phydev) dp83822->set_gpio2_clk_out = true; } + dp83822->tx_amplitude_100base_tx_index = -1; + ret = phy_get_tx_amplitude_gain(phydev, dev, + ETHTOOL_LINK_MODE_100baseT_Full_BIT, + &val); + if (!ret) { + for (i = 0; i < ARRAY_SIZE(tx_amplitude_100base_tx_gain); i++) { + if (tx_amplitude_100base_tx_gain[i] == val) { + dp83822->tx_amplitude_100base_tx_index = i; + break; + } + } + + if (dp83822->tx_amplitude_100base_tx_index < 0) { + phydev_err(phydev, + "Invalid value for tx-amplitude-100base-tx-percent property (%u)\n", + val); + return -EINVAL; + } + } + return dp83822_of_init_leds(phydev); }