diff options
Diffstat (limited to 'drivers/net/dsa/microchip/ksz_common.c')
| -rw-r--r-- | drivers/net/dsa/microchip/ksz_common.c | 135 |
1 files changed, 107 insertions, 28 deletions
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index 89f0796894af..f95a9aac56ee 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -265,16 +265,70 @@ static void ksz_phylink_mac_link_down(struct phylink_config *config, unsigned int mode, phy_interface_t interface); +/** + * ksz_phylink_mac_disable_tx_lpi() - Callback to signal LPI support (Dummy) + * @config: phylink config structure + * + * This function is a dummy handler. See ksz_phylink_mac_enable_tx_lpi() for + * a detailed explanation of EEE/LPI handling in KSZ switches. + */ +static void ksz_phylink_mac_disable_tx_lpi(struct phylink_config *config) +{ +} + +/** + * ksz_phylink_mac_enable_tx_lpi() - Callback to signal LPI support (Dummy) + * @config: phylink config structure + * @timer: timer value before entering LPI (unused) + * @tx_clock_stop: whether to stop the TX clock in LPI mode (unused) + * + * This function signals to phylink that the driver architecture supports + * LPI management, enabling phylink to control EEE advertisement during + * negotiation according to IEEE Std 802.3 (Clause 78). + * + * Hardware Management of EEE/LPI State: + * For KSZ switch ports with integrated PHYs (e.g., KSZ9893R ports 1-2), + * observation and testing suggest that the actual EEE / Low Power Idle (LPI) + * state transitions are managed autonomously by the hardware based on + * the auto-negotiation results. (Note: While the datasheet describes EEE + * operation based on negotiation, it doesn't explicitly detail the internal + * MAC/PHY interaction, so autonomous hardware management of the MAC state + * for LPI is inferred from observed behavior). + * This hardware control, consistent with the switch's ability to operate + * autonomously via strapping, means MAC-level software intervention is not + * required or exposed for managing the LPI state once EEE is negotiated. + * (Ref: KSZ9893R Data Sheet DS00002420D, primarily Section 4.7.5 explaining + * EEE, also Sections 4.1.7 on Auto-Negotiation and 3.2.1 on Configuration + * Straps). + * + * Additionally, ports configured as MAC interfaces (e.g., KSZ9893R port 3) + * lack documented MAC-level LPI control. + * + * Therefore, this callback performs no action and serves primarily to inform + * phylink of LPI awareness and to document the inferred hardware behavior. + * + * Returns: 0 (Always success) + */ +static int ksz_phylink_mac_enable_tx_lpi(struct phylink_config *config, + u32 timer, bool tx_clock_stop) +{ + return 0; +} + static const struct phylink_mac_ops ksz88x3_phylink_mac_ops = { .mac_config = ksz88x3_phylink_mac_config, .mac_link_down = ksz_phylink_mac_link_down, .mac_link_up = ksz8_phylink_mac_link_up, + .mac_disable_tx_lpi = ksz_phylink_mac_disable_tx_lpi, + .mac_enable_tx_lpi = ksz_phylink_mac_enable_tx_lpi, }; static const struct phylink_mac_ops ksz8_phylink_mac_ops = { .mac_config = ksz_phylink_mac_config, .mac_link_down = ksz_phylink_mac_link_down, .mac_link_up = ksz8_phylink_mac_link_up, + .mac_disable_tx_lpi = ksz_phylink_mac_disable_tx_lpi, + .mac_enable_tx_lpi = ksz_phylink_mac_enable_tx_lpi, }; static const struct ksz_dev_ops ksz88xx_dev_ops = { @@ -358,6 +412,8 @@ static const struct phylink_mac_ops ksz9477_phylink_mac_ops = { .mac_config = ksz_phylink_mac_config, .mac_link_down = ksz_phylink_mac_link_down, .mac_link_up = ksz9477_phylink_mac_link_up, + .mac_disable_tx_lpi = ksz_phylink_mac_disable_tx_lpi, + .mac_enable_tx_lpi = ksz_phylink_mac_enable_tx_lpi, }; static const struct ksz_dev_ops ksz9477_dev_ops = { @@ -401,6 +457,8 @@ static const struct phylink_mac_ops lan937x_phylink_mac_ops = { .mac_config = ksz_phylink_mac_config, .mac_link_down = ksz_phylink_mac_link_down, .mac_link_up = ksz9477_phylink_mac_link_up, + .mac_disable_tx_lpi = ksz_phylink_mac_disable_tx_lpi, + .mac_enable_tx_lpi = ksz_phylink_mac_enable_tx_lpi, }; static const struct ksz_dev_ops lan937x_dev_ops = { @@ -2016,6 +2074,18 @@ static void ksz_phylink_get_caps(struct dsa_switch *ds, int port, if (dev->dev_ops->get_caps) dev->dev_ops->get_caps(dev, port, config); + + if (ds->ops->support_eee && ds->ops->support_eee(ds, port)) { + memcpy(config->lpi_interfaces, config->supported_interfaces, + sizeof(config->lpi_interfaces)); + + config->lpi_capabilities = MAC_100FD; + if (dev->info->gbit_capable[port]) + config->lpi_capabilities |= MAC_1000FD; + + /* EEE is fully operational */ + config->eee_enabled_default = true; + } } void ksz_r_mib_stats64(struct ksz_device *dev, int port) @@ -3008,31 +3078,6 @@ static u32 ksz_get_phy_flags(struct dsa_switch *ds, int port) if (!port) return MICREL_KSZ8_P1_ERRATA; break; - case KSZ8567_CHIP_ID: - /* KSZ8567R Errata DS80000752C Module 4 */ - case KSZ8765_CHIP_ID: - case KSZ8794_CHIP_ID: - case KSZ8795_CHIP_ID: - /* KSZ879x/KSZ877x/KSZ876x Errata DS80000687C Module 2 */ - case KSZ9477_CHIP_ID: - /* KSZ9477S Errata DS80000754A Module 4 */ - case KSZ9567_CHIP_ID: - /* KSZ9567S Errata DS80000756A Module 4 */ - case KSZ9896_CHIP_ID: - /* KSZ9896C Errata DS80000757A Module 3 */ - case KSZ9897_CHIP_ID: - case LAN9646_CHIP_ID: - /* KSZ9897R Errata DS80000758C Module 4 */ - /* Energy Efficient Ethernet (EEE) feature select must be manually disabled - * The EEE feature is enabled by default, but it is not fully - * operational. It must be manually disabled through register - * controls. If not disabled, the PHY ports can auto-negotiate - * to enable EEE, and this feature can cause link drops when - * linked to another device supporting EEE. - * - * The same item appears in the errata for all switches above. - */ - return MICREL_NO_EEE; } return 0; @@ -3466,6 +3511,20 @@ static int ksz_max_mtu(struct dsa_switch *ds, int port) return -EOPNOTSUPP; } +/** + * ksz_support_eee - Determine Energy Efficient Ethernet (EEE) support for a + * port + * @ds: Pointer to the DSA switch structure + * @port: Port number to check + * + * This function also documents devices where EEE was initially advertised but + * later withdrawn due to reliability issues, as described in official errata + * documents. These devices are explicitly listed to record known limitations, + * even if there is no technical necessity for runtime checks. + * + * Returns: true if the internal PHY on the given port supports fully + * operational EEE, false otherwise. + */ static bool ksz_support_eee(struct dsa_switch *ds, int port) { struct ksz_device *dev = ds->priv; @@ -3475,15 +3534,35 @@ static bool ksz_support_eee(struct dsa_switch *ds, int port) switch (dev->chip_id) { case KSZ8563_CHIP_ID: + case KSZ9563_CHIP_ID: + case KSZ9893_CHIP_ID: + return true; case KSZ8567_CHIP_ID: + /* KSZ8567R Errata DS80000752C Module 4 */ + case KSZ8765_CHIP_ID: + case KSZ8794_CHIP_ID: + case KSZ8795_CHIP_ID: + /* KSZ879x/KSZ877x/KSZ876x Errata DS80000687C Module 2 */ case KSZ9477_CHIP_ID: - case KSZ9563_CHIP_ID: + /* KSZ9477S Errata DS80000754A Module 4 */ case KSZ9567_CHIP_ID: - case KSZ9893_CHIP_ID: + /* KSZ9567S Errata DS80000756A Module 4 */ case KSZ9896_CHIP_ID: + /* KSZ9896C Errata DS80000757A Module 3 */ case KSZ9897_CHIP_ID: case LAN9646_CHIP_ID: - return true; + /* KSZ9897R Errata DS80000758C Module 4 */ + /* Energy Efficient Ethernet (EEE) feature select must be + * manually disabled + * The EEE feature is enabled by default, but it is not fully + * operational. It must be manually disabled through register + * controls. If not disabled, the PHY ports can auto-negotiate + * to enable EEE, and this feature can cause link drops when + * linked to another device supporting EEE. + * + * The same item appears in the errata for all switches above. + */ + break; } return false; |