diff options
| author | Kory Maincent <kory.maincent@bootlin.com> | 2024-07-09 15:53:36 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-07-15 08:02:26 -0700 |
| commit | 2dd35600590148d843367c04975acad3c1a527c3 (patch) | |
| tree | 3133e7a29bd2cf1511c7a6c7889bc79fe4b8c964 /include/linux/phy.h | |
| parent | e50bfd6bb231a6e2b7221ad78dce294330238c76 (diff) | |
net: Change the API of PHY default timestamp to MAC
Change the API to select MAC default time stamping instead of the PHY.
Indeed the PHY is closer to the wire therefore theoretically it has less
delay than the MAC timestamping but the reality is different. Due to lower
time stamping clock frequency, latency in the MDIO bus and no PHC hardware
synchronization between different PHY, the PHY PTP is often less precise
than the MAC. The exception is for PHY designed specially for PTP case but
these devices are not very widespread. For not breaking the compatibility
default_timestamp flag has been introduced in phy_device that is set by
the phy driver to know we are using the old API behavior.
Reviewed-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20240709-feature_ptp_netnext-v17-4-b5317f50df2a@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux/phy.h')
| -rw-r--r-- | include/linux/phy.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/phy.h b/include/linux/phy.h index bd68f9d8e74f..e7a38137211c 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -616,6 +616,8 @@ struct macsec_ops; * handling shall be postponed until PHY has resumed * @irq_rerun: Flag indicating interrupts occurred while PHY was suspended, * requiring a rerun of the interrupt handler after resume + * @default_timestamp: Flag indicating whether we are using the phy + * timestamp as the default one * @interface: enum phy_interface_t value * @possible_interfaces: bitmap if interface modes that the attached PHY * will switch between depending on media speed. @@ -681,6 +683,8 @@ struct phy_device { unsigned irq_suspended:1; unsigned irq_rerun:1; + unsigned default_timestamp:1; + int rate_matching; enum phy_state state; @@ -1626,6 +1630,21 @@ static inline void phy_txtstamp(struct phy_device *phydev, struct sk_buff *skb, } /** + * phy_is_default_hwtstamp - Is the PHY hwtstamp the default timestamp + * @phydev: Pointer to phy_device + * + * This is used to get default timestamping device taking into account + * the new API choice, which is selecting the timestamping from MAC by + * default if the phydev does not have default_timestamp flag enabled. + * + * Return: True if phy is the default hw timestamp, false otherwise. + */ +static inline bool phy_is_default_hwtstamp(struct phy_device *phydev) +{ + return phy_has_hwtstamp(phydev) && phydev->default_timestamp; +} + +/** * phy_is_internal - Convenience function for testing if a PHY is internal * @phydev: the phy_device struct */ |