Re: [PATCH net-next v2 3/5] net: phy: update in-band AN mode when changing interface by PHY driver

Choong Yong Liang
2023-08-10T09:24:04Z

On 4/8/2023 5:02 pm, Russell King (Oracle) wrote:
> On Fri, Aug 04, 2023 at 04:45:25PM +0800, Choong Yong Liang wrote:
>> From: "Tan, Tee Min" <tee.min.tan@linux.intel.com>
>>
>> Add cur_link_an_mode into phy_device struct for PHY drivers to
>> communicate the in-band AN mode setting with phylink framework.
>>
>> As there is a mechanism in PHY drivers to switch the PHY interface
>> between SGMII and 2500BaseX according to link speed. In this case,
>> the in-band AN mode should be switching based on the PHY interface
>> as well, if the PHY interface has been changed/updated by PHY driver.
>>
>> For e.g., disable in-band AN in 2500BaseX mode, or enable in-band AN
>> back for SGMII mode (10/100/1000Mbps).
>>
>> Signed-off-by: Tan, Tee Min <tee.min.tan@linux.intel.com>
>> Signed-off-by: Choong Yong Liang <yong.liang.choong@linux.intel.com>
>> ---
>> drivers/net/phy/marvell10g.c | 6 ++++++
>> drivers/net/phy/phylink.c | 4 ++++
>> include/linux/phy.h | 3 +++
>> 3 files changed, 13 insertions(+)
>>
>> diff --git a/drivers/net/phy/marvell10g.c b/drivers/net/phy/marvell10g.c
>> index d4bb90d76881..a9df19278618 100644
>> --- a/drivers/net/phy/marvell10g.c
>> +++ b/drivers/net/phy/marvell10g.c
>> @@ -30,6 +30,7 @@
>> #include <linux/phy.h>
>> #include <linux/sfp.h>
>> #include <linux/netdevice.h>
>> +#include <linux/phylink.h>
>>
>> #define MV_PHY_ALASKA_NBT_QUIRK_MASK 0xfffffffe
>> #define MV_PHY_ALASKA_NBT_QUIRK_REV (MARVELL_PHY_ID_88X3310 | 0xa)
>> @@ -946,6 +947,9 @@ static void mv3310_update_interface(struct phy_device *phydev)
>> * xaui / rxaui modes according to the speed.
>> * Florian suggests setting phydev->interface to communicate this to the
>> * MAC. Only do this if we are already in one of the above modes.
>> + * In-band Auto-negotiation is not supported in 2500BASE-X.
>> + * Setting phydev->cur_link_an_mode to communicate this to the
>> + * phylink framework.
>> */
>> switch (phydev->speed) {
>> case SPEED_10000:
>> @@ -956,11 +960,13 @@ static void mv3310_update_interface(struct phy_device *phydev)
>> break;
>> case SPEED_2500:
>> phydev->interface = PHY_INTERFACE_MODE_2500BASEX;
>> + phydev->cur_link_an_mode = MLO_AN_PHY;
>> break;
>> case SPEED_1000:
>> case SPEED_100:
>> case SPEED_10:
>> phydev->interface = PHY_INTERFACE_MODE_SGMII;
>> + phydev->cur_link_an_mode = MLO_AN_INBAND;
>> break;
>> default:
>> break;
>> diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
>> index 4f1c8bb199e9..f9cbb6d7e134 100644
>> --- a/drivers/net/phy/phylink.c
>> +++ b/drivers/net/phy/phylink.c
>> @@ -1720,6 +1720,8 @@ static void phylink_phy_change(struct phy_device *phydev, bool up)
>> pl->phy_state.pause |= MLO_PAUSE_RX;
>> pl->phy_state.interface = phydev->interface;
>> pl->phy_state.link = up;
>> + pl->cur_link_an_mode = phydev->cur_link_an_mode;
>> + pl->cfg_link_an_mode = phydev->cur_link_an_mode;
>> mutex_unlock(&pl->state_mutex);
>>
>> phylink_run_resolve(pl);
>> @@ -1824,6 +1826,8 @@ static int phylink_bringup_phy(struct phylink *pl, struct phy_device *phy,
>> if (pl->config->mac_managed_pm)
>> phy->mac_managed_pm = true;
>>
>> + pl->phydev->cur_link_an_mode = pl->cur_link_an_mode;
>
> I am really not happy with exposing phylink's AN mode into phylib.
>
Hi Russell,

Thank you for the feedback.
After conducting further analysis on my end, it appears that this line
"pl->phydev->cur_link_an_mode = pl->cur_link_an_mode;" is not necessary.
If we remove this line of code, would the implementation of this patch be
acceptable to you?