From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) (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 D17652FFDE1; Mon, 27 Apr 2026 09:52:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777283531; cv=none; b=BfO8th1ioKPcewPZ10v3I6JLLMMv4pL+qEnugAtMQvfv3VFmSQ3pWhtzgo2agHsd09KGH2QW4TTJP6prPs2SSTxVx1ml4NhMNHQqjq/BARGY9qjpEbhuTESWZVvCHKglOD4v8qd2WZwkQkKlXBQhSgKHIvxUn7lSYTU1K6U8DX4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777283531; c=relaxed/simple; bh=3ScpVu6cd+qG8bDqwMH9nLLo7ljJEm+ttcCR8fkeroc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=O3LCG2yxOulLXQPy1LdXhJeoYiDWNB5yFv5ShavNDBPnYkl5J7qDQ1MglorBO23jQtkj5iLhaxzNAvRjVgc5XluAzBodJa8F8kehRvv7jdAFDBGyXEtp1thB4EsTTBQrmt0IXPS2YeOmUnQq4A1N4kNGnBso5zPIqkQ+e3WWpSY= 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=eGJTX6Ow; arc=none smtp.client-ip=198.175.65.15 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="eGJTX6Ow" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1777283530; x=1808819530; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=3ScpVu6cd+qG8bDqwMH9nLLo7ljJEm+ttcCR8fkeroc=; b=eGJTX6OwZL70AybYuQkg8EkqIya8P1IU5fynQ86fd91jrB56kzKmKxq4 JeiKT7Dl/fJQsLKUOYoJNR/Y8/N35G2hUQd+jreDXWoWmv/VyyTIUlSWr qgsiKheoFAn9ITkE+xaGeP9KVasuP3XZnvLw3LPw7IXkrmCQO6FsK9JqJ ObsZSvDOJQH/Cl/xDndSMBOlVlNRgy06yhUP/uHcXqPj/XRoNnfG+/t+U McMxElDxGD1kPopsFInJL4nqR83s8cfsxLfLvJquwWVkVhKPAPRzosUEe B/mhdxJaPsf47zyPkhngnbQwiMllngfN1RWkLgOPm9OIN416s1cv+R86w A==; X-CSE-ConnectionGUID: eMJ3aHQkTZa4nY+mcm2oXQ== X-CSE-MsgGUID: kU9HqWK3QHGRdDdsxLdxIw== X-IronPort-AV: E=McAfee;i="6800,10657,11768"; a="81775654" X-IronPort-AV: E=Sophos;i="6.23,201,1770624000"; d="scan'208";a="81775654" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by orvoesa107.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Apr 2026 02:52:10 -0700 X-CSE-ConnectionGUID: x6YF+sgUTPGQwgPOysOEng== X-CSE-MsgGUID: 34g8Pw/aRW+Zn8ka784p5g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,201,1770624000"; d="scan'208";a="237916743" Received: from mohdfai2-mobl.gar.corp.intel.com (HELO [10.247.80.101]) ([10.247.80.101]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Apr 2026 02:52:05 -0700 Message-ID: <7b10fe32-4f3f-4473-ae69-82af901b7a1f@linux.intel.com> Date: Mon, 27 Apr 2026 17:52:03 +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: [PATCH iwl-next v3 3/3] igc: add support for forcing link speed without autonegotiation To: Simon Horman , 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, Looi@web.codeaurora.org References: <20260422155701.7420-1-khai.wen.tan@linux.intel.com> <20260422155701.7420-4-khai.wen.tan@linux.intel.com> <20260424135958.GL900403@horms.kernel.org> Content-Language: en-US From: "Abdul Rahim, Faizal" In-Reply-To: <20260424135958.GL900403@horms.kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 24/4/2026 9:59 pm, Simon Horman wrote: > 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. Will update, thanks.