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  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]
Date:   Wed, 11 Aug 2021 07:55:29 +0800
From:   Wong Vee Khee <>
To:     Andrew Lunn <>
Cc:     Vivien Didelot <>,
        Florian Fainelli <>,
        "David S . Miller" <>,
        Jakub Kicinski <>,
        Giuseppe Cavallaro <>,
        Alexandre Torgue <>,
        Jose Abreu <>,
        Maxime Coquelin <>,
        Heiner Kallweit <>,
        Russell King <>,
        Voon Weifeng <>,
        Michael Sit Wei Hong <>,
        Vladimir Oltean <>,,,,
Subject: Re: [PATCH net-next 1/2] net: pcs: xpcs: enable skip xPCS soft reset

Hi Andrew,
On Mon, Aug 09, 2021 at 03:35:09PM +0200, Andrew Lunn wrote:
> On Mon, Aug 09, 2021 at 06:22:28PM +0800, Wong Vee Khee wrote:
> > From: Michael Sit Wei Hong <>
> > 
> > Unlike any other platforms, Intel AlderLake-S uses Synopsys SerDes where
> > all the SerDes PLL configurations are controlled by the xPCS at the BIOS
> > level. If the driver perform a xPCS soft reset on initialization, these
> > settings will be switched back to the power on reset values.
> > 
> > This changes the xpcs_create function to take in an additional argument
> > to check if the platform request to skip xPCS soft reset during device
> > initialization.
> Why not just call into the BIOS and ask it to configure the SERDES?
> Isn't that what ACPI is all about, hiding the details from the OS? Or
> did the BIOS writers not add a control method to do this?
>     Andrew

BIOS does configured the SerDes. The problem here is that all the
configurations done by BIOS are being reset at xpcs_create().

We would want user of the pcs-xpcs module (stmmac, sja1105) to have
control whether or not we need to perform to the soft reset in the
xpcs_create() call.

Hope that explained.


Powered by blists - more mailing lists