From 87f062ed853ce75f9f71fd2f7aa9887ee7e8ba65 Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Mon, 27 Nov 2023 15:50:59 +0100 Subject: [PATCH 1/3] net: dsa: microchip: ksz8: Make flow control, speed, and duplex on CPU port configurable Allow flow control, speed, and duplex settings on the CPU port to be configurable. Previously, the speed and duplex relied on default switch values, which limited flexibility. Additionally, flow control was hardcoded and only functional in duplex mode. This update enhances the configurability of these parameters. Signed-off-by: Oleksij Rempel Reviewed-by: Simon Horman Reviewed-by: Vladimir Oltean Reviewed-by: Florian Fainelli Reviewed-by: Russell King (Oracle) Link: https://lore.kernel.org/r/20231127145101.3039399-2-o.rempel@pengutronix.de Signed-off-by: Jakub Kicinski --- drivers/net/dsa/microchip/ksz8.h | 4 ++ drivers/net/dsa/microchip/ksz8795.c | 53 +++++++++++++++++++++++++- drivers/net/dsa/microchip/ksz_common.c | 1 + 3 files changed, 56 insertions(+), 2 deletions(-) diff --git a/drivers/net/dsa/microchip/ksz8.h b/drivers/net/dsa/microchip/ksz8.h index 4cea811e73ac6..1a5225264e6a3 100644 --- a/drivers/net/dsa/microchip/ksz8.h +++ b/drivers/net/dsa/microchip/ksz8.h @@ -56,5 +56,9 @@ int ksz8_reset_switch(struct ksz_device *dev); int ksz8_switch_init(struct ksz_device *dev); void ksz8_switch_exit(struct ksz_device *dev); int ksz8_change_mtu(struct ksz_device *dev, int port, int mtu); +void ksz8_phylink_mac_link_up(struct ksz_device *dev, int port, + unsigned int mode, phy_interface_t interface, + struct phy_device *phydev, int speed, int duplex, + bool tx_pause, bool rx_pause); #endif diff --git a/drivers/net/dsa/microchip/ksz8795.c b/drivers/net/dsa/microchip/ksz8795.c index 4bf4d67557dcf..88b10aa527d6b 100644 --- a/drivers/net/dsa/microchip/ksz8795.c +++ b/drivers/net/dsa/microchip/ksz8795.c @@ -1439,6 +1439,57 @@ void ksz8_config_cpu_port(struct dsa_switch *ds) } } +/** + * ksz8_cpu_port_link_up - Configures the CPU port of the switch. + * @dev: The KSZ device instance. + * @speed: The desired link speed. + * @duplex: The desired duplex mode. + * @tx_pause: If true, enables transmit pause. + * @rx_pause: If true, enables receive pause. + * + * Description: + * The function configures flow control and speed settings for the CPU + * port of the switch based on the desired settings, current duplex mode, and + * speed. + */ +static void ksz8_cpu_port_link_up(struct ksz_device *dev, int speed, int duplex, + bool tx_pause, bool rx_pause) +{ + const u16 *regs = dev->info->regs; + u8 ctrl = 0; + + /* SW_FLOW_CTRL, SW_HALF_DUPLEX, and SW_10_MBIT bits are bootstrappable + * at least on KSZ8873. They can have different values depending on your + * board setup. + */ + if (tx_pause || rx_pause) + ctrl |= SW_FLOW_CTRL; + + if (duplex == DUPLEX_HALF) + ctrl |= SW_HALF_DUPLEX; + + /* This hardware only supports SPEED_10 and SPEED_100. For SPEED_10 + * we need to set the SW_10_MBIT bit. Otherwise, we can leave it 0. + */ + if (speed == SPEED_10) + ctrl |= SW_10_MBIT; + + ksz_rmw8(dev, regs[S_BROADCAST_CTRL], SW_HALF_DUPLEX | SW_FLOW_CTRL | + SW_10_MBIT, ctrl); +} + +void ksz8_phylink_mac_link_up(struct ksz_device *dev, int port, + unsigned int mode, phy_interface_t interface, + struct phy_device *phydev, int speed, int duplex, + bool tx_pause, bool rx_pause) +{ + /* If the port is the CPU port, apply special handling. Only the CPU + * port is configured via global registers. + */ + if (dev->cpu_port == port) + ksz8_cpu_port_link_up(dev, speed, duplex, tx_pause, rx_pause); +} + static int ksz8_handle_global_errata(struct dsa_switch *ds) { struct ksz_device *dev = ds->priv; @@ -1487,8 +1538,6 @@ int ksz8_setup(struct dsa_switch *ds) */ ds->vlan_filtering_is_global = true; - ksz_cfg(dev, S_REPLACE_VID_CTRL, SW_FLOW_CTRL, true); - /* Enable automatic fast aging when link changed detected. */ ksz_cfg(dev, S_LINK_AGING_CTRL, SW_LINK_AUTO_AGING, true); diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index 3fed406fb46ae..0ee7cfb8d4bd5 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -277,6 +277,7 @@ static const struct ksz_dev_ops ksz8_dev_ops = { .mirror_add = ksz8_port_mirror_add, .mirror_del = ksz8_port_mirror_del, .get_caps = ksz8_get_caps, + .phylink_mac_link_up = ksz8_phylink_mac_link_up, .config_cpu_port = ksz8_config_cpu_port, .enable_stp_addr = ksz8_enable_stp_addr, .reset = ksz8_reset_switch, From 2f58148c41e23e11f16e79308455d82ab9342607 Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Mon, 27 Nov 2023 15:51:00 +0100 Subject: [PATCH 2/3] net: dsa: microchip: ksz8: Add function to configure ports with integrated PHYs This patch introduces the function 'ksz8_phy_port_link_up' to the Microchip KSZ8xxx driver. This function is responsible for setting up flow control and duplex settings for the ports that are integrated with PHYs. The KSZ8795 switch supports asymmetric pause control, which can't be fully utilized since a single bit controls both RX and TX pause. Despite this, the flow control can be adjusted based on the auto-negotiation process, taking into account the capabilities of both link partners. On the other hand, the KSZ8873's PORT_FORCE_FLOW_CTRL bit can be set by the hardware bootstrap, which ignores the auto-negotiation result. Therefore, even in auto-negotiation mode, we need to ensure that this bit is correctly set. When auto-negotiation isn't in use, we enforce symmetric pause control for the KSZ8795 switch. Please note, forcing flow control disable on a port while still advertising pause support isn't possible. While this scenario might not be practical or desired, it's important to be aware of this limitation when working with the KSZ8873 and similar devices. Signed-off-by: Oleksij Rempel Reviewed-by: Simon Horman Reviewed-by: Florian Fainelli Reviewed-by: Russell King (Oracle) Link: https://lore.kernel.org/r/20231127145101.3039399-3-o.rempel@pengutronix.de Signed-off-by: Jakub Kicinski --- drivers/net/dsa/microchip/ksz8795.c | 70 ++++++++++++++++++++++++++ drivers/net/dsa/microchip/ksz_common.c | 4 +- drivers/net/dsa/microchip/ksz_common.h | 1 + 3 files changed, 74 insertions(+), 1 deletion(-) diff --git a/drivers/net/dsa/microchip/ksz8795.c b/drivers/net/dsa/microchip/ksz8795.c index 88b10aa527d6b..ec1ddfcf7473a 100644 --- a/drivers/net/dsa/microchip/ksz8795.c +++ b/drivers/net/dsa/microchip/ksz8795.c @@ -1439,6 +1439,74 @@ void ksz8_config_cpu_port(struct dsa_switch *ds) } } +/** + * ksz8_phy_port_link_up - Configures ports with integrated PHYs + * @dev: The KSZ device instance. + * @port: The port number to configure. + * @duplex: The desired duplex mode. + * @tx_pause: If true, enables transmit pause. + * @rx_pause: If true, enables receive pause. + * + * Description: + * The function configures flow control settings for a given port based on the + * desired settings and current duplex mode. + * + * According to the KSZ8873 datasheet, the PORT_FORCE_FLOW_CTRL bit in the + * Port Control 2 register (0x1A for Port 1, 0x22 for Port 2, 0x32 for Port 3) + * determines how flow control is handled on the port: + * "1 = will always enable full-duplex flow control on the port, regardless + * of AN result. + * 0 = full-duplex flow control is enabled based on AN result." + * + * This means that the flow control behavior depends on the state of this bit: + * - If PORT_FORCE_FLOW_CTRL is set to 1, the switch will ignore AN results and + * force flow control on the port. + * - If PORT_FORCE_FLOW_CTRL is set to 0, the switch will enable or disable + * flow control based on the AN results. + * + * However, there is a potential limitation in this configuration. It is + * currently not possible to force disable flow control on a port if we still + * advertise pause support. While such a configuration is not currently + * supported by Linux, and may not make practical sense, it's important to be + * aware of this limitation when working with the KSZ8873 and similar devices. + */ +static void ksz8_phy_port_link_up(struct ksz_device *dev, int port, int duplex, + bool tx_pause, bool rx_pause) +{ + const u16 *regs = dev->info->regs; + u8 sctrl = 0; + + /* The KSZ8795 switch differs from the KSZ8873 by supporting + * asymmetric pause control. However, since a single bit is used to + * control both RX and TX pause, we can't enforce asymmetric pause + * control - both TX and RX pause will be either enabled or disabled + * together. + * + * If auto-negotiation is enabled, we usually allow the flow control to + * be determined by the auto-negotiation process based on the + * capabilities of both link partners. However, for KSZ8873, the + * PORT_FORCE_FLOW_CTRL bit may be set by the hardware bootstrap, + * ignoring the auto-negotiation result. Thus, even in auto-negotiation + * mode, we need to ensure that the PORT_FORCE_FLOW_CTRL bit is + * properly cleared. + * + * In the absence of pause auto-negotiation, we will enforce symmetric + * pause control for both variants of switches - KSZ8873 and KSZ8795. + * + * Autoneg Pause Autoneg rx,tx PORT_FORCE_FLOW_CTRL + * 1 1 x 0 + * 0 1 x 0 (flow control probably disabled) + * x 0 1 1 (flow control force enabled) + * 1 0 0 0 (flow control still depends on + * aneg result due to hardware) + * 0 0 0 0 (flow control probably disabled) + */ + if (dev->ports[port].manual_flow && tx_pause) + sctrl |= PORT_FORCE_FLOW_CTRL; + + ksz_prmw8(dev, port, regs[P_STP_CTRL], PORT_FORCE_FLOW_CTRL, sctrl); +} + /** * ksz8_cpu_port_link_up - Configures the CPU port of the switch. * @dev: The KSZ device instance. @@ -1488,6 +1556,8 @@ void ksz8_phylink_mac_link_up(struct ksz_device *dev, int port, */ if (dev->cpu_port == port) ksz8_cpu_port_link_up(dev, speed, duplex, tx_pause, rx_pause); + else if (dev->info->internal_phy[port]) + ksz8_phy_port_link_up(dev, port, duplex, tx_pause, rx_pause); } static int ksz8_handle_global_errata(struct dsa_switch *ds) diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index 0ee7cfb8d4bd5..3b1fe9aff6a81 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -2967,8 +2967,10 @@ static void ksz_phylink_mac_config(struct dsa_switch *ds, int port, { struct ksz_device *dev = ds->priv; - if (ksz_is_ksz88x3(dev)) + if (ksz_is_ksz88x3(dev)) { + dev->ports[port].manual_flow = !(state->pause & MLO_PAUSE_AN); return; + } /* Internal PHYs */ if (dev->info->internal_phy[port]) diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h index b7e8a403a132f..d1a1c876ba0da 100644 --- a/drivers/net/dsa/microchip/ksz_common.h +++ b/drivers/net/dsa/microchip/ksz_common.h @@ -134,6 +134,7 @@ struct ksz_port { ktime_t tstamp_msg; struct completion tstamp_msg_comp; #endif + bool manual_flow; }; struct ksz_device { From 71cd5ce7e2f390de105b118a330ffe40a3417bdc Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Mon, 27 Nov 2023 15:51:01 +0100 Subject: [PATCH 3/3] net: dsa: microchip: make phylink_mac_link_up() not optional Last part of the driver do now support phylink_mac_link_up(). So, make it not optional. Signed-off-by: Oleksij Rempel Reviewed-by: Florian Fainelli Reviewed-by: Russell King (Oracle) Link: https://lore.kernel.org/r/20231127145101.3039399-4-o.rempel@pengutronix.de Signed-off-by: Jakub Kicinski --- drivers/net/dsa/microchip/ksz_common.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index 3b1fe9aff6a81..9545aed905f50 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -3113,10 +3113,8 @@ static void ksz_phylink_mac_link_up(struct dsa_switch *ds, int port, { struct ksz_device *dev = ds->priv; - if (dev->dev_ops->phylink_mac_link_up) - dev->dev_ops->phylink_mac_link_up(dev, port, mode, interface, - phydev, speed, duplex, - tx_pause, rx_pause); + dev->dev_ops->phylink_mac_link_up(dev, port, mode, interface, phydev, + speed, duplex, tx_pause, rx_pause); } static int ksz_switch_detect(struct ksz_device *dev)