From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx3.molgen.mpg.de (mx3.molgen.mpg.de [141.14.17.11]) (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 1979037CD3D; Tue, 28 Apr 2026 15:07:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=141.14.17.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777388862; cv=none; b=foAxyOjAzIoR4lmDpOlyw1WKXWYl7ViuO9+bAy5P7AY+6eszuMdALSWGC340z1EeB50UxEIpy7obtH+cconTE/a5uyaMm1bDF22pmuWtQ8ZzVmqqeTouYhKXrwaUjqSVs/kjnOSCVZl88tYQORlw/uyf+Cox2n8XRzUzohYcI/8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777388862; c=relaxed/simple; bh=FWcTVjds0C9y5CpVpjxBQ30dXbhQ4u1EVVvXJBuYBAs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=a0yGf7Oe9KCK8lK5AbQCQy4MuAYNSC0jUi4e8V73ju8LHPUELEhfmVzX4HVQmzB0UqCo0rkvR4gp8n5sIDjsRlGbl0sVFIYdkMal/F107evVJqHlOGw1dukX3gchYoY49DXvWJqcK3e/CRYsMxCbFqYUVtJnAhWDvlmf7goQu20= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=molgen.mpg.de; spf=pass smtp.mailfrom=molgen.mpg.de; arc=none smtp.client-ip=141.14.17.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=molgen.mpg.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=molgen.mpg.de Received: from [141.14.220.42] (g42.guest.molgen.mpg.de [141.14.220.42]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: pmenzel) by mx.molgen.mpg.de (Postfix) with ESMTPSA id 524524C4431132; Tue, 28 Apr 2026 17:06:26 +0200 (CEST) Message-ID: Date: Tue, 28 Apr 2026 17:06:25 +0200 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: Faizal Abdul Rahim Cc: khai.wen.tan@linux.intel.com, 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> <84b4f8bb-3c8c-4098-bc7f-7e9fd248c5ca@linux.intel.com> Content-Language: en-US From: Paul Menzel In-Reply-To: <84b4f8bb-3c8c-4098-bc7f-7e9fd248c5ca@linux.intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Dear Faizal, Am 28.04.26 um 12:39 schrieb Abdul Rahim, Faizal: > On 28/4/2026 2:56 pm, Paul Menzel wrote: >> 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. Thank you. For me the information about just supporting copper would be great to have in the commit message. >>> 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 Just for your information, that your mailer wraps the lines of the quotes. […] >>>    * 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