linux-kernel - Re: [PATCH net-next] net: pcs: tse: port to pcs-lynx

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230211215229.ra43h35rbuibpj2p@skbuf>
Date:   Sat, 11 Feb 2023 23:52:29 +0200
From:   Vladimir Oltean <vladimir.oltean@....com>
To:     Andrew Lunn <andrew@...n.ch>
Cc:     Maxime Chevallier <maxime.chevallier@...tlin.com>,
        davem@...emloft.net, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org, thomas.petazzoni@...tlin.com,
        Jakub Kicinski <kuba@...nel.org>,
        Eric Dumazet <edumazet@...gle.com>,
        Paolo Abeni <pabeni@...hat.com>,
        Florian Fainelli <f.fainelli@...il.com>,
        Heiner Kallweit <hkallweit1@...il.com>,
        Russell King <linux@...linux.org.uk>,
        linux-arm-kernel@...ts.infradead.org,
        Ioana Ciornei <ioana.ciornei@....com>
Subject: Re: [PATCH net-next] net: pcs: tse: port to pcs-lynx

On Fri, Feb 10, 2023 at 09:02:39PM +0100, Andrew Lunn wrote:
> I was wondering if the glue could actually be made generic. The kernel
> has a number of reasonably generic MMIO device drivers, which are just
> given an address range and assume a logical mapping.
> 
> Could this be made into a generic MDIO MMIO bus driver, which just
> gets configured with a base address, and maybe a stride between
> registers?

This sounds interesting to me because I also have at least one other
potential use for it. The "nxp,sja1110-base-tx-mdio" driver does basically
just that, except it's SPI instead of MMIO. So if the generic driver was a
platform device driver and it was aware of dev_get_regmap(), it could
get reused.

What I'm not sure of is the spacing between MDIO registers. For the
SJA1110 CBTX PHY, the registers are 32-bit wide (but contain 16-bit
values). So MII_BMCR is at offset 0x0, MII_BMSR at 0x4 etc. I'd imagine
that other MDIO buses might have MII_BMSR at 0x2.