From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] r8169: set RxConfig after tx/rx is enabled for
 RTL8169sb/8110sb devices
Date: Mon, 27 Aug 2018 15:25:26 -0700 (PDT)
Message-ID: <20180827.152526.373553144560078421.davem@davemloft.net>
References: <20180826140309.32310-1-a3at.mail@gmail.com>
Mime-Version: 1.0
Content-Type: Text/Plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Cc: netdev@vger.kernel.org, hkallweit1@gmail.com, nic_swsd@realtek.com
To: a3at.mail@gmail.com
Return-path: <netdev-owner@vger.kernel.org>
Received: from shards.monkeyblade.net ([23.128.96.9]:33714 "EHLO
        shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1726994AbeH1COB (ORCPT
        <rfc822;netdev@vger.kernel.org>); Mon, 27 Aug 2018 22:14:01 -0400
In-Reply-To: <20180826140309.32310-1-a3at.mail@gmail.com>
Sender: netdev-owner@vger.kernel.org
List-ID: <netdev.vger.kernel.org>

From: Azat Khuzhin <a3at.mail@gmail.com>
Date: Sun, 26 Aug 2018 17:03:09 +0300

> I have two Ethernet adapters:
>   r8169 0000:03:01.0 eth0: RTL8169sb/8110sb, 00:14:d1:14:2d:49, XID 10000000, IRQ 18
>   r8169 0000:01:00.0 eth0: RTL8168e/8111e, 64:66:b3:11:14:5d, XID 2c200000, IRQ 30
> And after upgrading from linux 4.15 [1] to linux 4.18+ [2] RTL8169sb failed to
> receive any packets. tcpdump shows a lot of checksum mismatch.
> 
>   [1]: a0f79386a4968b4925da6db2d1daffd0605a4402
>   [2]: 0519359784328bfa92bf0931bf0cff3b58c16932 (4.19 merge window opened)
> 
> I started bisecting and the found that [3] breaks it. According to [4]:
>   "For 8110S, 8110SB, and 8110SC series, the initial value of RxConfig
>   needs to be set after the tx/rx is enabled."
> So I moved rtl_init_rxcfg() after enabling tx/rs and now my adapter works
> (RTL8168e works too).
> 
>   [3]: 3559d81e76bfe3803e89f2e04cf6ef7ab4f3aace
>   [4]: e542a2269f232d61270ceddd42b73a4348dee2bb ("r8169: adjust the RxConfig
> settings.")
> 
> Also drop "rx" from rtl_set_rx_tx_config_registers(), since it does nothing
> with it already.
> 
> Fixes: 3559d81e76bfe3803e89f2e04cf6ef7ab4f3aace ("r8169: simplify
> rtl_hw_start_8169")
> 
> Cc: Heiner Kallweit <hkallweit1@gmail.com>
> Cc: David S. Miller <davem@davemloft.net>
> Cc: netdev@vger.kernel.org
> Cc: Realtek linux nic maintainers <nic_swsd@realtek.com>
> Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com>
> ---
> It looks like calling rtl_init_rxcfg() the second time is fine, but I
> can move it into rtl_hw_start_8169())

Heiner, please review.