RE: [Intel-wired-lan] [PATCHv3 net] igb: Fix extts capture value format for 82580/i354/i350

[Pucha, HimasekharX Reddy]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@xxxxxxxxxx> On Behalf Of Yuezhen Luan
> Sent: Friday, June 2, 2023 12:34 PM
> To: Brandeburg, Jesse <jesse.brandeburg@xxxxxxxxx>; Nguyen, Anthony L <anthony.l.nguyen@xxxxxxxxx>; davem@xxxxxxxxxxxxx; edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx; pabeni@xxxxxxxxxx
> Cc: netdev@xxxxxxxxxxxxxxx; intel-wired-lan@xxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Yuezhen Luan <eggcar.luan@xxxxxxxxx>
> Subject: [Intel-wired-lan] [PATCHv3 net] igb: Fix extts capture value format for 82580/i354/i350
>
> 82580/i354/i350 features circle-counter-like timestamp registers that are different with newer i210. The EXTTS capture value in AUXTSMPx should be converted from raw circle counter value to timestamp value in resolution of 1 nanosec by the driver.
>
> This issue can be reproduced on i350 nics, connecting an 1PPS signal to a SDP pin, and run 'ts2phc' command to read external 1PPS timestamp value. On i210 this works fine, but on i350 the extts is not correctly converted.
>
> The i350/i354/82580's SYSTIM and other timestamp registers are 40bit counters, presenting time range of 2^40 ns, that means these registers overflows every about 1099s. This causes all these regs can't be > used directly in contrast to the newer i210/i211s.
>
> The igb driver needs to convert these raw register values to valid time stamp format by using kernel timecounter apis for i350s families. Here the igb_extts() just forgot to do the convert.
>
> Fixes: 38970eac41db ("igb: support EXTTS on 82580/i354/i350")
> Signed-off-by: Yuezhen Luan <eggcar.luan@xxxxxxxxx>
> ---
> V2 -> V3: Add 'Fixes' tag, and add 'net' tag in patch title
> V1 -> V2: Fix typo in the source code, and add detailed explanation
>
> drivers/net/ethernet/intel/igb/igb_main.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>

Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@xxxxxxxxx> (A Contingent worker at Intel)