| Message ID | 20240911212713.2178943-6-maxime.chevallier@bootlin.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Allow controlling PHY loopback and isolate modes | expand |
Hi Maxime, On Wed, Sep 11, 2024 at 11:27:09PM +0200, Maxime Chevallier wrote: ... > > +/** > + * struct phy_device_config - General PHY device configuration parameters for > + * status reporting and bulk configuration > + * > + * A structure containing generic PHY device information, allowing to expose > + * internal status to userspace, and perform PHY configuration in a controlled > + * manner. > + * > + * @isolate: The MII-side isolation status of the PHY > + * @loopback: The loopback state of the PHY > + */ > +struct phy_device_config { > + bool isolate; > + bool loopback; > +}; I would recommend to have loopback enum. There are different levels of loopback: https://www.ti.com/document-viewer/DP83TD510E/datasheet#GUID-50834313-DEF1-42FB-BA00-9B0902B2D7E4/TITLE-SNLS656SNLS5055224 I imagine something like this: /* * enum phy_loopback_mode - PHY loopback modes * These modes represent different loopback configurations to * facilitate in-circuit testing of the PHY's digital and analog paths. */ enum phy_loopback_mode { PHY_LOOPBACK_NONE = 0, /* No loopback mode enabled */ PHY_LOOPBACK_MII, /* MII Loopback: MAC to PHY internal loopback */ PHY_LOOPBACK_PCS, /* PCS Loopback: PCS layer loopback, no signal processing */ PHY_LOOPBACK_DIGITAL, /* Digital Loopback: Loops back entire digital TX/RX path */ PHY_LOOPBACK_ANALOG, /* Analog Loopback: Loops back after analog front-end */ PHY_LOOPBACK_FAR_END /* Far-End (Reverse) Loopback: Receiver to MAC interface loopback */ }; At same time, one interface will have multiple loopback providers, except of multiple PHYs, MAC will provide it too. I assume, we need a bit field per component to reflect supported loopback modes. If you have time, please take a look at net/core/selftests.c this will be one of consumers which should walk over different loopback levels to find the location of potential problem. Regards, Oleksij
Hello Oleksij, On Thu, 12 Sep 2024 06:46:29 +0200 Oleksij Rempel <o.rempel@pengutronix.de> wrote: > Hi Maxime, > > On Wed, Sep 11, 2024 at 11:27:09PM +0200, Maxime Chevallier wrote: > ... > > > > +/** > > + * struct phy_device_config - General PHY device configuration parameters for > > + * status reporting and bulk configuration > > + * > > + * A structure containing generic PHY device information, allowing to expose > > + * internal status to userspace, and perform PHY configuration in a controlled > > + * manner. > > + * > > + * @isolate: The MII-side isolation status of the PHY > > + * @loopback: The loopback state of the PHY > > + */ > > +struct phy_device_config { > > + bool isolate; > > + bool loopback; > > +}; > > I would recommend to have loopback enum. There are different levels of > loopback: > https://www.ti.com/document-viewer/DP83TD510E/datasheet#GUID-50834313-DEF1-42FB-BA00-9B0902B2D7E4/TITLE-SNLS656SNLS5055224 > > I imagine something like this: > > /* > * enum phy_loopback_mode - PHY loopback modes > * These modes represent different loopback configurations to > * facilitate in-circuit testing of the PHY's digital and analog paths. > */ > enum phy_loopback_mode { > PHY_LOOPBACK_NONE = 0, /* No loopback mode enabled */ > PHY_LOOPBACK_MII, /* MII Loopback: MAC to PHY internal loopback */ > PHY_LOOPBACK_PCS, /* PCS Loopback: PCS layer loopback, no signal processing */ > PHY_LOOPBACK_DIGITAL, /* Digital Loopback: Loops back entire digital TX/RX path */ > PHY_LOOPBACK_ANALOG, /* Analog Loopback: Loops back after analog front-end */ > PHY_LOOPBACK_FAR_END /* Far-End (Reverse) Loopback: Receiver to MAC interface loopback */ > }; I agree with you on that, having the ability to fine-tune where the loopback happens is really useful for debug. The main problem I would see is to come-up with a set of modes that are somewhat generic, as vendors implement a wide variety of loopback modes. For example, on BaseT4 PHYs the Analog loopback doesn't exist and is more akin to using a loopback stub, whereas the Digital loopback would be a loopback at the PMD level (I don't know if that even exists). That being said, the list of possible places to setup the loopback within a PHY is finite and it's conceivable to come-up with a set of loopback modes. Thanks a lot for the feedback, Maxime
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c index 4f3e742907cb..0cdb0fc30727 100644 --- a/drivers/net/phy/phy.c +++ b/drivers/net/phy/phy.c @@ -1811,3 +1811,62 @@ int phy_ethtool_nway_reset(struct net_device *ndev) return ret; } EXPORT_SYMBOL(phy_ethtool_nway_reset); + +/** + * phy_get_config - Get PHY configuration parameters + * @phydev: the PHY device to act upon + * @phy_cfg: The configuration to apply + */ + +int phy_get_config(struct phy_device *phydev, + struct phy_device_config *phy_cfg) +{ + mutex_lock(&phydev->lock); + phy_cfg->isolate = phydev->isolated; + phy_cfg->loopback = phydev->loopback_enabled; + mutex_unlock(&phydev->lock); + + return 0; +} + +/** + * phy_set_config - Set PHY configuration parameters + * @phydev: the PHY device to act upon + * @phy_cfg: the configuration to apply + * @extack: a netlink extack for useful error reporting + */ + +int phy_set_config(struct phy_device *phydev, + const struct phy_device_config *phy_cfg, + struct netlink_ext_ack *extack) +{ + bool loopback_change, isolate_change; + int ret; + + /* As the phydev's loopback and isolation state are protected by the + * phy lock, check first if we'll need to perform the action, + * then do them as a second step. + */ + mutex_lock(&phydev->lock); + isolate_change = (phy_cfg->isolate != phydev->isolated); + loopback_change = (phy_cfg->loopback != phydev->loopback_enabled); + mutex_unlock(&phydev->lock); + + if (isolate_change) { + ret = phy_isolate(phydev, phy_cfg->isolate); + if (ret) { + NL_SET_ERR_MSG(extack, "Error while configuring PHY isolation"); + return ret; + } + } + + if (loopback_change) { + ret = phy_loopback(phydev, phy_cfg->loopback); + if (ret) { + NL_SET_ERR_MSG(extack, "Error while configuring PHY loopback"); + return ret; + } + } + + return 0; +} diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 2a3db1043626..0714a2b83d18 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -3845,6 +3845,8 @@ static const struct ethtool_phy_ops phy_ethtool_phy_ops = { .get_plca_status = phy_ethtool_get_plca_status, .start_cable_test = phy_start_cable_test, .start_cable_test_tdr = phy_start_cable_test_tdr, + .get_config = phy_get_config, + .set_config = phy_set_config, }; static const struct phylib_stubs __phylib_stubs = { diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index 12f6dc567598..480ee99a69a5 100644 --- a/include/linux/ethtool.h +++ b/include/linux/ethtool.h @@ -1140,6 +1140,7 @@ struct phy_device; struct phy_tdr_config; struct phy_plca_cfg; struct phy_plca_status; +struct phy_device_config; /** * struct ethtool_phy_ops - Optional PHY device options @@ -1151,6 +1152,8 @@ struct phy_plca_status; * @get_plca_status: Get PLCA configuration. * @start_cable_test: Start a cable test * @start_cable_test_tdr: Start a Time Domain Reflectometry cable test + * @get_config: Retrieve phy device configuration parameters + * @set_config: Set phy device configuration parameters * * All operations are optional (i.e. the function pointer may be set to %NULL) * and callers must take this into account. Callers must hold the RTNL lock. @@ -1172,6 +1175,11 @@ struct ethtool_phy_ops { int (*start_cable_test_tdr)(struct phy_device *phydev, struct netlink_ext_ack *extack, const struct phy_tdr_config *config); + int (*get_config)(struct phy_device *phydev, + struct phy_device_config *phy_cfg); + int (*set_config)(struct phy_device *phydev, + const struct phy_device_config *phy_cfg, + struct netlink_ext_ack *extack); }; /** diff --git a/include/linux/phy.h b/include/linux/phy.h index f0a8a5459fbe..ee0364d2afc3 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -887,6 +887,22 @@ enum phy_led_modes { __PHY_LED_MODES_NUM, }; +/** + * struct phy_device_config - General PHY device configuration parameters for + * status reporting and bulk configuration + * + * A structure containing generic PHY device information, allowing to expose + * internal status to userspace, and perform PHY configuration in a controlled + * manner. + * + * @isolate: The MII-side isolation status of the PHY + * @loopback: The loopback state of the PHY + */ +struct phy_device_config { + bool isolate; + bool loopback; +}; + /** * struct phy_led: An LED driven by the PHY * @@ -2067,6 +2083,11 @@ int phy_ethtool_set_plca_cfg(struct phy_device *phydev, struct netlink_ext_ack *extack); int phy_ethtool_get_plca_status(struct phy_device *phydev, struct phy_plca_status *plca_st); +int phy_get_config(struct phy_device *phydev, + struct phy_device_config *phy_cfg); +int phy_set_config(struct phy_device *phydev, + const struct phy_device_config *phy_cfg, + struct netlink_ext_ack *extack); int __phy_hwtstamp_get(struct phy_device *phydev, struct kernel_hwtstamp_config *config);
Expose phy-specific configuration hooks to get and set the state of an ethernet PHY's internal configuration. So far, these parameters include the loopback state of the PHY (host-side loopback) and the isolation state of the PHY. The .get_config() ethtool_phy_ops gets these status information from the phy_device's internal flags, while the .set_config() operation allows changing these configuration parameters. Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> --- drivers/net/phy/phy.c | 59 ++++++++++++++++++++++++++++++++++++ drivers/net/phy/phy_device.c | 2 ++ include/linux/ethtool.h | 8 +++++ include/linux/phy.h | 21 +++++++++++++ 4 files changed, 90 insertions(+)