Date:   Sat, 11 Mar 2023 00:49:03 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Klaus Kudielka <klaus.kudielka@gmail.com>
Cc:     Michael Walle <michael@walle.cc>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, Felix Fietkau <nbd@nbd.name>,
        John Crispin <john@phrozen.org>,
        Sean Wang <sean.wang@mediatek.com>,
        Mark Lee <Mark-MC.Lee@mediatek.com>,
        Lorenzo Bianconi <lorenzo@kernel.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Bryan Whitehead <bryan.whitehead@microchip.com>,
        UNGLinuxDriver@microchip.com,
        Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Joel Stanley <joel@jms.id.au>,
        Andrew Jeffery <andrew@aj.id.au>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-aspeed@lists.ozlabs.org,
        Jesse Brandeburg <jesse.brandeburg@intel.com>
Subject: Re: [PATCH net-next v2 4/6] net: mdio: scan bus based on bus
 capabilities for C22 and C45
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> Yes, that helps. Primarily, because mdiobus_scan_bus_c45 now is called only once,
> and at least some things are done in parallel.

Great. Could you cook up a proper patch and submit it?

> (Still, ~2s waiting for the C45 scan to complete).

The number of times it polled for the bit is somewhat high. The silly
thing here is, you are doing MDIO over MDIO. The inner MDIO bus should
be just as fast as the outer MDIO bus, both around 2.5MHz. So i don't
see why it should need to loop more than once waiting for the inner
MDIO to complete..

     Andrew