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Date:   Mon, 24 Jul 2023 13:56:15 +0200
From:   Simon Horman <simon.horman@corigine.com>
To:     Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc:     Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Heiner Kallweit <hkallweit1@gmail.com>, netdev@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        kernel@axis.com
Subject: Re: [PATCH net] net: stmmac: Apply redundant write work around on
 4.xx too
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References: <20230721-stmmac-tx-workaround-v1-1-9411cbd5ee07@axis.com>
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On Fri, Jul 21, 2023 at 03:39:20PM +0200, Vincent Whitchurch wrote:
> commit a3a57bf07de23fe1ff779e0fdf710aa581c3ff73 ("net: stmmac: work
> around sporadic tx issue on link-up") worked around a problem with TX
> sometimes not working after a link-up by avoiding a redundant write to
> MAC_CTRL_REG (aka GMAC_CONFIG), since the IP appeared to have problems
> with handling multiple writes to that register in some cases.
> 
> That commit however only added the work around to dwmac_lib.c (apart
> from the common code in stmmac_main.c), but my systems with version
> 4.21a of the IP exhibit the same problem, so add the work around to
> dwmac4_lib.c too.
> 
> Fixes: a3a57bf07de2 ("net: stmmac: work around sporadic tx issue on link-up")
> Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>

Reviewed-by: Simon Horman <simon.horman@corigine.com>