From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 9740F3DA5A2; Fri, 24 Apr 2026 14:00:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777039204; cv=none; b=aK436DzGKWVtm8Rd587Ekk9lTWM1lSODqy/BGYVTqF3/NVJHkso1drcBYbTrxHtUOsYtezZHkdV+kiWUaQUfjEsN9hm5kJcj0jKyuhUe7masU14rk8yKzvl93mpoUeyX/8H4QjuyQ/POvtECWwJAVThHwR67KbrvEago+cHKu5E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777039204; c=relaxed/simple; bh=RjPXRwAeTtKHltjAE51ItOPdDhf9jKLVKaPyYVF/kmU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qSSY3jr9DGCLPL5kZ+4fFO8Dz1NyKT5NAcuxRTcOh/L1hkTt+utEEJzkOMxpnp3h2tjoHE499/PaAdKyFPMjLAzMweh3elM3mqgblWl+oAXpaYFw5FtsMsBRrN/DzYmRGrwCM+V+2IZgRVyF3p4JMuogutJ/yQ711OPw9eJDHJU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Nsfc9I4A; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Nsfc9I4A" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79FE5C19425; Fri, 24 Apr 2026 14:00:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777039204; bh=RjPXRwAeTtKHltjAE51ItOPdDhf9jKLVKaPyYVF/kmU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Nsfc9I4AdaKxHCRy2KFb+Y9+EwjnpX/Y3Yee7SewGiwoqUS87ru385v9QS+AC9Tlu Ev3ri/Dr7iQBhFV+L87rM+SimKLIGXXiM6UYXxJXYsmB/Vp/QaHyqvL4mZkRFAkFxQ 9rCN98ZbQK56Q+a87wdUSZ1mrSU1olCyLjOmPqGFQt+KtgeG0fLKk/zyMepzkf/02g QZnfzl65gmd34GvAzunuH8Yuc/JYGIcQSKSaAfFPrFgkUImH1kZjq0LkSeyj9r6J4P P1CnBYb9FuNWtgSbosp6yrG30e0rB5gR6m5tPWIVQdMiLJ9kvAERwJuo140yk0GKsK DMleeFOSEzqGw== Date: Fri, 24 Apr 2026 14:59:58 +0100 From: Simon Horman To: KhaiWenTan Cc: anthony.l.nguyen@intel.com, przemyslaw.kitszel@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, Faizal Rahim , Looi Subject: Re: [PATCH iwl-next v3 3/3] igc: add support for forcing link speed without autonegotiation Message-ID: <20260424135958.GL900403@horms.kernel.org> References: <20260422155701.7420-1-khai.wen.tan@linux.intel.com> <20260422155701.7420-4-khai.wen.tan@linux.intel.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260422155701.7420-4-khai.wen.tan@linux.intel.com> On Wed, Apr 22, 2026 at 11:57:01PM +0800, KhaiWenTan wrote: > From: Faizal Rahim > > Allow users to force 10/100 Mb/s link speed and duplex via ethtool > when autonegotiation is disabled. Previously, the driver rejected > these requests with "Force mode currently not supported.". > > Forcing at 1000 Mb/s and 2500 Mb/s is not supported. > > Reviewed-by: Looi, Hong Aun > Signed-off-by: Faizal Rahim > Signed-off-by: KhaiWenTan ... > diff --git a/drivers/net/ethernet/intel/igc/igc_ethtool.c b/drivers/net/ethernet/intel/igc/igc_ethtool.c ... > @@ -2000,6 +2013,41 @@ static int igc_ethtool_get_link_ksettings(struct net_device *netdev, > return 0; > } > > +/** > + * igc_handle_autoneg_disabled - Configure forced speed/duplex settings > + * @adapter: private driver structure > + * @speed: requested speed (must be SPEED_10 or SPEED_100) > + * @duplex: requested duplex > + * > + * Records forced speed/duplex when autoneg is disabled. > + * Caller must validate speed before calling this function. > + */ > +static void igc_handle_autoneg_disabled(struct igc_adapter *adapter, u32 speed, > + u8 duplex) > +{ > + struct igc_mac_info *mac = &adapter->hw.mac; > + > + switch (speed) { > + case SPEED_10: > + mac->forced_speed_duplex = (duplex == DUPLEX_FULL) ? > + IGC_FORCED_10F : IGC_FORCED_10H; > + break; > + case SPEED_100: > + mac->forced_speed_duplex = (duplex == DUPLEX_FULL) ? > + IGC_FORCED_100F : IGC_FORCED_100H; > + break; > + default: > + WARN_ONCE(1, "Unsupported speed %u\n", speed); > + return; > + } > + > + mac->autoneg_enabled = false; > + > + /* Half-duplex cannot support flow control per IEEE 802.3 */ > + if (duplex != DUPLEX_FULL) > + adapter->hw.fc.requested_mode = igc_fc_none; > +} > + > /** > * igc_handle_autoneg_enabled - Configure autonegotiation advertisement > * @adapter: private driver structure > @@ -2038,6 +2086,7 @@ static void igc_handle_autoneg_enabled(struct igc_adapter *adapter, > 10baseT_Half)) > advertised |= ADVERTISE_10_HALF; > > + hw->mac.autoneg_enabled = true; > hw->phy.autoneg_advertised = advertised; > if (adapter->fc_autoneg) > hw->fc.requested_mode = igc_fc_default; > @@ -2071,14 +2120,20 @@ igc_ethtool_set_link_ksettings(struct net_device *netdev, > } > } > > + if (cmd->base.autoneg == AUTONEG_DISABLE && > + cmd->base.speed != SPEED_10 && cmd->base.speed != SPEED_100) { > + netdev_info(dev, "Unsupported speed for forced link\n"); > + return -EINVAL; > + } The condition above verifies speed only if autoneg is AUTONEG_DISABLE. > + > while (test_and_set_bit(__IGC_RESETTING, &adapter->state)) > usleep_range(1000, 2000); > > - if (cmd->base.autoneg == AUTONEG_ENABLE) { > + if (cmd->base.autoneg == AUTONEG_ENABLE) > igc_handle_autoneg_enabled(adapter, cmd); > - } else { > - netdev_info(dev, "Force mode currently not supported\n"); > - } > + else > + igc_handle_autoneg_disabled(adapter, cmd->base.speed, > + cmd->base.duplex); But here igc_handle_autoneg_disabled, which relies on speed having been verified, is called if autoneg is not AUTONEG_ENABLE. If autoneg is AUTONEG_DISABLE here, then all is good. But if it is neither AUTONEG_DISABLE nor AUTONEG_ENABLE then we are in trouble. I suggest verifying autoneg is either AUTONEG_ENABLE or AUTONEG_DISABLE earlier in this function. The above is based on my analysis of review AI generated review from Sashiko. I believe that addressing autoneg verification address the review by Sashiko that is relevant to the progress of this patch. ...