From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6A95B3E0C5A; Tue, 28 Apr 2026 10:39:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777372755; cv=none; b=ph8zNLc0BtJD/qrlnAghlf/E/vJOiClFCSULgwLP848jDS0kBXaBIoXFNXbSYanBMtRSFme4MzgzYzKXA16wUAqtcW0nyPR4yyIy8FdNvA6gXSNziFbf4laE5wmMl0lMayQhGDy+InL4bTAGdxuuJGJBw9WX1wqomv6asZAmBoE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777372755; c=relaxed/simple; bh=Bgc9zNw8/VIIqORJYTIMHdUjkk5pjcVenC5PsPgEqi8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=GdBdNvNAKz4V2SYx3+H+WuozpRSh71N0PLr08oKmH2UvjG0OctwMIe7fJfSVJbpZpuToFj+hqBv4QdnTdSA5S7OVfl8FKYrdXDiW9u0WYsWHAoIN5AjKXg9x8aa06IonjqJkSnxX7ATjZ3sI3y1iF/Vp14OnBXD8KfN/5RnNt0k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=OYwOZAqw; arc=none smtp.client-ip=192.198.163.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="OYwOZAqw" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1777372754; x=1808908754; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=Bgc9zNw8/VIIqORJYTIMHdUjkk5pjcVenC5PsPgEqi8=; b=OYwOZAqwpQhGYpftplENX2d9cWM0+hyvNX6thfvE2qEXvkJXvvGadM8Z /h3A4eg1fnVPMcL+7/fCeXkJ7VSJcBnUsCnq+t9nDR9QyHl/BkP+vFUin /Tkdw5Y+4PK2XxyTdSXYLtcYvO5CLT+SDrNI2JJcw6Cc0U5WtS6RlTVF8 rNTFgQutJX3P/Rouc8qwi+OmVPd2nOMmJrJ9aOFPMsiZRDdUts+5CA5bl DCNc8eiOHs6LXVSXj7mT8HCkOdao0U04hEvwTo2d2KGgZIZ0SAQdfHE2x deWioRrsMZRsqc5sRcPgt6vc3+T6heyfBN5pb7Y5eTmVM3nhWEkd0Dvf9 g==; X-CSE-ConnectionGUID: b9d+Ua6vR2KXvcPFS9Zs6A== X-CSE-MsgGUID: aJ8bGpsRQpKAuGO9QNavGg== X-IronPort-AV: E=McAfee;i="6800,10657,11769"; a="82129661" X-IronPort-AV: E=Sophos;i="6.23,203,1770624000"; d="scan'208";a="82129661" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by fmvoesa106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Apr 2026 03:39:13 -0700 X-CSE-ConnectionGUID: b4j4xyRwTby95FsK2JPPBw== X-CSE-MsgGUID: +lgNgHwhSai15uUy7ChhtQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,203,1770624000"; d="scan'208";a="231273121" Received: from mohdfai2-mobl.gar.corp.intel.com (HELO [10.247.81.233]) ([10.247.81.233]) by fmviesa008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Apr 2026 03:39:09 -0700 Message-ID: <84b4f8bb-3c8c-4098-bc7f-7e9fd248c5ca@linux.intel.com> Date: Tue, 28 Apr 2026 18:39:06 +0800 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [Intel-wired-lan] [PATCH iwl-next v4 1/3] igc: remove unused autoneg_failed field To: Paul Menzel , khai.wen.tan@linux.intel.com Cc: anthony.l.nguyen@intel.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, faizal.abdul.rahim@intel.com, hong.aun.looi@intel.com, khai.wen.tan@intel.com, Aleksandr Loktionov References: <20260428060009.311393-1-khai.wen.tan@linux.intel.com> <20260428060009.311393-2-khai.wen.tan@linux.intel.com> Content-Language: en-US From: "Abdul Rahim, Faizal" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hi Paul, Thank you for your review. On 28/4/2026 2:56 pm, Paul Menzel wrote: > [Cc: Removed stray *Looi*] > > Dear Khai Wen Tan, > > > Thank you for your patch. > > > Am 28.04.26 um 08:00 schrieb KhaiWenTan: > > (Should spaces be added in your name?) > >> From: Faizal Rahim >> >> autoneg_failed in struct igc_mac_info is never set in the igc driver. >> Remove the field and the dead code checking it in >> igc_config_fc_after_link_up(). > > Could you please elaborate. Why is removal the correct fix, and it’s not an > incomplete feature? Does auto-negotiation always succeed? > Auto-negotiation does not always succeed, but igc does not use autoneg_failed to handle that case, the field was never set anywhere in the igc driver. Before this patch, the only igc references to autoneg_failed were the struct member declaration and the read in igc_config_fc_after_link_up(). No igc code ever assigned it to true, and git history shows no commit that added a setter since the code creation in 2018. The field originates from the e1000/e1000e fiber/serdes forced-link path: when MAC-level auto-negotiation on fiber times out, the driver forces link up and sets autoneg_failed so the flow-control code knows pause was not negotiated and must be forced. igc has no fiber or serdes media, it only supports copper (igc_media_type_copper), so the code that sets autoneg_failed was never ported. On copper, PHY auto-negotiation failure is handled differently: - No link at all: igc_check_for_copper_link() returns before reaching flow-control configuration, there's nothing to configure FC on. - Link present but autoneg not yet complete: igc_config_fc_after_link_up() checks MII_SR_AUTONEG_COMPLETE and returns early without resolving pause. The next link-status event re-triggers the check. - Autoneg completes (including via parallel detection fallback when the link partner doesn't autoneg): the PHY still sets AUTONEG_COMPLETE but LP_ABILITY won't have PAUSE bits since the partner never sent autoneg pages. The existing flow-control logic in igc_config_fc_after_link_up() handles that correctly, it falls through to igc_fc_none or igc_fc_rx_pause based on requested_mode. None of these paths need autoneg_failed. Keeping the field would be misleading to reader. >> Reviewed-by: Looi, Hong Aun > > Please order it to not use the comma: Hong Aun Looi > Will do, thanks. >> Reviewed-by: Aleksandr Loktionov >> Signed-off-by: Faizal Rahim >> Signed-off-by: KhaiWenTan >> --- >>   drivers/net/ethernet/intel/igc/igc_hw.h  |  1 - >>   drivers/net/ethernet/intel/igc/igc_mac.c | 16 +--------------- >>   2 files changed, 1 insertion(+), 16 deletions(-) >> >> diff --git a/drivers/net/ethernet/intel/igc/igc_hw.h b/drivers/net/ >> ethernet/intel/igc/igc_hw.h >> index be8a49a86d09..86ab8f566f44 100644 >> --- a/drivers/net/ethernet/intel/igc/igc_hw.h >> +++ b/drivers/net/ethernet/intel/igc/igc_hw.h >> @@ -92,7 +92,6 @@ struct igc_mac_info { >>       bool asf_firmware_present; >>       bool arc_subsystem_valid; >> >> -    bool autoneg_failed; >>       bool get_link_status; >>   }; >> >> diff --git a/drivers/net/ethernet/intel/igc/igc_mac.c b/drivers/net/ >> ethernet/intel/igc/igc_mac.c >> index 7ac6637f8db7..142beb9ae557 100644 >> --- a/drivers/net/ethernet/intel/igc/igc_mac.c >> +++ b/drivers/net/ethernet/intel/igc/igc_mac.c >> @@ -438,28 +438,14 @@ void igc_config_collision_dist(struct igc_hw *hw) >>    * Checks the status of auto-negotiation after link up to ensure that the >>    * speed and duplex were not forced.  If the link needed to be forced, >> then >>    * flow control needs to be forced also.  If auto-negotiation is enabled >> - * and did not fail, then we configure flow control based on our link >> - * partner. >> + * then we configure flow control based on our link partner. >>    */ >>   s32 igc_config_fc_after_link_up(struct igc_hw *hw) >>   { >>       u16 mii_status_reg, mii_nway_adv_reg, mii_nway_lp_ability_reg; >> -    struct igc_mac_info *mac = &hw->mac; >>       u16 speed, duplex; >>       s32 ret_val = 0; >> >> -    /* Check for the case where we have fiber media and auto-neg failed >> -     * so we had to force link.  In this case, we need to force the >> -     * configuration of the MAC to match the "fc" parameter. >> -     */ >> -    if (mac->autoneg_failed) >> -        ret_val = igc_force_mac_fc(hw); >> - >> -    if (ret_val) { >> -        hw_dbg("Error forcing flow control settings\n"); >> -        goto out; >> -    } >> - >>       /* In auto-neg, we need to check and see if Auto-Neg has completed, >>        * and if so, how the PHY and link partner has flow control >>        * configured. > > > Kind regards, > > Paul >