netdev - Re: [PATCH net-next] octeontx2-af: cn10k: devlink params to configure TIM

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>] [day] [month] [year] [list]

Date:   Mon, 29 Nov 2021 08:15:14 +0000
From:   Shijith Thotton <sthotton@...vell.com>
To:     Jakub Kicinski <kuba@...nel.org>
CC:     "davem@...emloft.net" <davem@...emloft.net>,
        Sunil Kovvuri Goutham <sgoutham@...vell.com>,
        Jerin Jacob Kollanukkaran <jerinj@...vell.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: [PATCH net-next] octeontx2-af: cn10k: devlink params to configure
 TIM

>> Added devlink parameters to configure the source clock of TIM block.
>> Supported clocks are TENNS, GPIOS, GTI, PTP, SYNC, BTS, EXT_MIO and
>> EXT_GTI.
>>
>> To adjust a given clock, the required delta can be written to the
>> corresponding tim_adjust_<clock> parameter and tim_adjust_timers
>> parameter can be used to trigger the adjustment. tim_capture_<clock>
>> parameter can be used to verify the adjusted values for a clock.
>>
>> Example using tenns clock source:
>> To adjust a clock source
>>  # devlink dev param set pci/0002:01:00.0 name tim_adjust_tenns \
>>         value "1000" cmode runtime
>>
>> To trigger adjustment
>>  # devlink dev param set pci/0002:01:00.0 name tim_adjust_timers \
>>         value 1 cmode runtime
>
>PTP subsystem exists.

TIM is a hardware block in Octeon TX2 DPU, which is used to generate events
like timeout (used in packet processing). TIM input needs to be configured with a
clock source for its working, but TIM does not act as a clock source. Supported
clocks for input are TENNS, GPIOS, GTI, PTP, SYNC, BTS and MIO. Devlink
parameters added in this patch are to configure TIM and won't be changing the
clock sources. 

We won't be able to use PTP subsystem here as the changes are specific to TIM.