diff --git a/drivers/net/ethernet/intel/ice/ice_ptp_hw.c b/drivers/net/ethernet/intel/ice/ice_ptp_hw.c index eb98f2781627f..10445bba65391 100644 --- a/drivers/net/ethernet/intel/ice/ice_ptp_hw.c +++ b/drivers/net/ethernet/intel/ice/ice_ptp_hw.c @@ -754,29 +754,32 @@ ice_read_phy_tstamp_e822(struct ice_hw *hw, u8 quad, u8 idx, u64 *tstamp) * @quad: the quad to read from * @idx: the timestamp index to reset * - * Clear a timestamp, resetting its valid bit, from the PHY quad block that is - * shared between the internal PHYs on the E822 devices. + * Read the timestamp out of the quad to clear its timestamp status bit from + * the PHY quad block that is shared between the internal PHYs of the E822 + * devices. + * + * Note that unlike E810, software cannot directly write to the quad memory + * bank registers. E822 relies on the ice_get_phy_tx_tstamp_ready() function + * to determine which timestamps are valid. Reading a timestamp auto-clears + * the valid bit. + * + * To directly clear the contents of the timestamp block entirely, discarding + * all timestamp data at once, software should instead use + * ice_ptp_reset_ts_memory_quad_e822(). + * + * This function should only be called on an idx whose bit is set according to + * ice_get_phy_tx_tstamp_ready(). */ static int ice_clear_phy_tstamp_e822(struct ice_hw *hw, u8 quad, u8 idx) { - u16 lo_addr, hi_addr; + u64 unused_tstamp; int err; - lo_addr = (u16)TS_L(Q_REG_TX_MEMORY_BANK_START, idx); - hi_addr = (u16)TS_H(Q_REG_TX_MEMORY_BANK_START, idx); - - err = ice_write_quad_reg_e822(hw, quad, lo_addr, 0); - if (err) { - ice_debug(hw, ICE_DBG_PTP, "Failed to clear low PTP timestamp register, err %d\n", - err); - return err; - } - - err = ice_write_quad_reg_e822(hw, quad, hi_addr, 0); + err = ice_read_phy_tstamp_e822(hw, quad, idx, &unused_tstamp); if (err) { - ice_debug(hw, ICE_DBG_PTP, "Failed to clear high PTP timestamp register, err %d\n", - err); + ice_debug(hw, ICE_DBG_PTP, "Failed to read the timestamp register for quad %u, idx %u, err %d\n", + quad, idx, err); return err; } @@ -2812,28 +2815,39 @@ ice_read_phy_tstamp_e810(struct ice_hw *hw, u8 lport, u8 idx, u64 *tstamp) * @lport: the lport to read from * @idx: the timestamp index to reset * - * Clear a timestamp, resetting its valid bit, from the timestamp block of the - * external PHY on the E810 device. + * Read the timestamp and then forcibly overwrite its value to clear the valid + * bit from the timestamp block of the external PHY on the E810 device. + * + * This function should only be called on an idx whose bit is set according to + * ice_get_phy_tx_tstamp_ready(). */ static int ice_clear_phy_tstamp_e810(struct ice_hw *hw, u8 lport, u8 idx) { u32 lo_addr, hi_addr; + u64 unused_tstamp; int err; + err = ice_read_phy_tstamp_e810(hw, lport, idx, &unused_tstamp); + if (err) { + ice_debug(hw, ICE_DBG_PTP, "Failed to read the timestamp register for lport %u, idx %u, err %d\n", + lport, idx, err); + return err; + } + lo_addr = TS_EXT(LOW_TX_MEMORY_BANK_START, lport, idx); hi_addr = TS_EXT(HIGH_TX_MEMORY_BANK_START, lport, idx); err = ice_write_phy_reg_e810(hw, lo_addr, 0); if (err) { - ice_debug(hw, ICE_DBG_PTP, "Failed to clear low PTP timestamp register, err %d\n", - err); + ice_debug(hw, ICE_DBG_PTP, "Failed to clear low PTP timestamp register for lport %u, idx %u, err %d\n", + lport, idx, err); return err; } err = ice_write_phy_reg_e810(hw, hi_addr, 0); if (err) { - ice_debug(hw, ICE_DBG_PTP, "Failed to clear high PTP timestamp register, err %d\n", - err); + ice_debug(hw, ICE_DBG_PTP, "Failed to clear high PTP timestamp register for lport %u, idx %u, err %d\n", + lport, idx, err); return err; } @@ -3515,9 +3529,15 @@ int ice_read_phy_tstamp(struct ice_hw *hw, u8 block, u8 idx, u64 *tstamp) * @block: the block to read from * @idx: the timestamp index to reset * - * Clear a timestamp, resetting its valid bit, from the timestamp block. For - * E822 devices, the block is the quad to clear from. For E810 devices, the - * block is the logical port to clear from. + * Clear a timestamp from the timestamp block, discarding its value without + * returning it. This resets the memory status bit for the timestamp index + * allowing it to be reused for another timestamp in the future. + * + * For E822 devices, the block number is the PHY quad to clear from. For E810 + * devices, the block number is the logical port to clear from. + * + * This function must only be called on a timestamp index whose valid bit is + * set according to ice_get_phy_tx_tstamp_ready(). */ int ice_clear_phy_tstamp(struct ice_hw *hw, u8 block, u8 idx) {