Re: [Intel-wired-lan] [PATCH iwl-net v3] ice: fall back to SBQ when LL PHY timer interface times out

> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf
> Of Przemyslaw Korba
> Sent: Friday, June 5, 2026 2:06 PM
> To: [email protected]
> Cc: [email protected]; Nguyen, Anthony L
> <[email protected]>; Kitszel, Przemyslaw
> <[email protected]>; Ilichev, Konstantin
> <[email protected]>; Lobakin, Aleksander
> <[email protected]>; Korba, Przemyslaw
> <[email protected]>
> Subject: [Intel-wired-lan] [PATCH iwl-net v3] ice: fall back to SBQ
> when LL PHY timer interface times out
> 
> The low-latency (LL) PHY timer interface relies on a tight, atomic
> poll of the PF_SB_ATQBAL register with a 2ms timeout. After an NVM
> update / EMPR, FW may need significantly longer than 2ms to start
> responding to ATQBAL commands. The first PHY adjust or incval write
> issued by
> ice_ptp_rebuild_owner() fails with -ETIMEDOUT.
> 
> Fix this by falling back to the existing SBQ-based PHY register write
> path when LL times out. This makes sure PTP is initialized when FW
> takes longer than expected to come back online.
> 
> Steps to reproduce:
> ./nvmupdate64e -if devlink -f
> Update E810 card with nvmupdate64e, and observe dmesg errors:
>   Failed to write PHC increment value, status -110
>   PTP reset failed, error: -110 (-ETIMEDOUT)
> 
> Fixes: ef9a64c07294 ("ice: implement low latency PHY timer updates")
> Signed-off-by: Przemyslaw Korba <[email protected]>
> ---
> v3:
> * actually add TIMEDOUT check in ice_prep_phy_adj_e810 (did do it)
> v2:
> * add TIMEDOUT check in ice_prep_phy_adj_e810 (did not do it)
> https://lore.kernel.org/intel-wired-lan/20260603114904.1297713-1-
> [email protected]/
> v1:
> https://lore.kernel.org/intel-wired-lan/20260511095830.1095984-1-
> [email protected]/
> ---
>  drivers/net/ethernet/intel/ice/ice_ptp_hw.c | 38 +++++++++++---------
> -
>  1 file changed, 20 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_ptp_hw.c
> b/drivers/net/ethernet/intel/ice/ice_ptp_hw.c
> index d47d5baf3281..e77c7f2b5575 100644
> --- a/drivers/net/ethernet/intel/ice/ice_ptp_hw.c
> +++ b/drivers/net/ethernet/intel/ice/ice_ptp_hw.c
> @@ -4789,15 +4789,12 @@ static int ice_ptp_prep_phy_adj_ll_e810(struct
> ice_hw *hw, s32 adj)
>  				       !FIELD_GET(REG_LL_PROXY_H_EXEC,
> val),
>  				       10, REG_LL_PROXY_H_TIMEOUT_US,
> false, hw,
>  				       REG_LL_PROXY_H);
> -	if (err) {
> -		ice_debug(hw, ICE_DBG_PTP, "Failed to prepare PHY timer
> adjustment using low latency interface\n");
> -		spin_unlock_irq(&params->atqbal_wq.lock);
> -		return err;
> -	}
> -
>  	spin_unlock_irq(&params->atqbal_wq.lock);
> 
> -	return 0;
> +	if (err)
> +		ice_debug(hw, ICE_DBG_PTP, "Failed to prepare PHY timer
> adjustment
> +using low latency interface\n");
> +
> +	return err;
>  }
> 
>  /**
> @@ -4818,8 +4815,12 @@ static int ice_ptp_prep_phy_adj_e810(struct
> ice_hw *hw, s32 adj)
>  	u8 tmr_idx;
>  	int err;
> 
> -	if (hw->dev_caps.ts_dev_info.ll_phy_tmr_update)
> -		return ice_ptp_prep_phy_adj_ll_e810(hw, adj);
> +	if (hw->dev_caps.ts_dev_info.ll_phy_tmr_update) {
> +		err = ice_ptp_prep_phy_adj_ll_e810(hw, adj);
> +		if (err != -ETIMEDOUT)
> +			return err;
> +		ice_debug(hw, ICE_DBG_PTP, "LL adj timed out, falling
> back to SBQ\n");
> +	}
> 
>  	tmr_idx = hw->func_caps.ts_func_info.tmr_index_owned;
> 
> @@ -4882,15 +4883,12 @@ static int
> ice_ptp_prep_phy_incval_ll_e810(struct ice_hw *hw, u64 incval)
>  				       !FIELD_GET(REG_LL_PROXY_H_EXEC,
> val),
>  				       10, REG_LL_PROXY_H_TIMEOUT_US,
> false, hw,
>  				       REG_LL_PROXY_H);
> -	if (err) {
> -		ice_debug(hw, ICE_DBG_PTP, "Failed to prepare PHY timer
> increment using low latency interface\n");
> -		spin_unlock_irq(&params->atqbal_wq.lock);
> -		return err;
> -	}
> -
>  	spin_unlock_irq(&params->atqbal_wq.lock);
> 
> -	return 0;
> +	if (err)
> +		ice_debug(hw, ICE_DBG_PTP, "Failed to prepare PHY timer
> increment
> +using low latency interface\n");
> +
> +	return err;
>  }
> 
>  /**
> @@ -4908,8 +4906,12 @@ static int ice_ptp_prep_phy_incval_e810(struct
> ice_hw *hw, u64 incval)
>  	u8 tmr_idx;
>  	int err;
> 
> -	if (hw->dev_caps.ts_dev_info.ll_phy_tmr_update)
> -		return ice_ptp_prep_phy_incval_ll_e810(hw, incval);
> +	if (hw->dev_caps.ts_dev_info.ll_phy_tmr_update) {
> +		err = ice_ptp_prep_phy_incval_ll_e810(hw, incval);
> +		if (err != -ETIMEDOUT)
> +			return err;
> +		ice_debug(hw, ICE_DBG_PTP, "LL incval timed out, falling
> back to SBQ\n");
> +	}
> 
>  	tmr_idx = hw->func_caps.ts_func_info.tmr_index_owned;
>  	low = lower_32_bits(incval);
> 
> base-commit: 2d72c95ac8e2d1abccf671d95b94532a8b2abb24
> --
> 2.43.0

Reviewed-by: Aleksandr Loktionov <[email protected]>