[Intel-wired-lan] [PATCH iwl-net v2 2/4] igc: Lengthen the hardware retry time to prevent timeouts

[Avigail Dahan]

On 23/10/2024 5:30, Chris H wrote:
> From: Christopher S M Hall <christopher.s.hall at intel.com>
> 
> Lengthen the hardware retry timer to four microseconds.
> 
> The i225/i226 hardware retries if it receives an inappropriate response
> from the upstream device. If the device retries too quickly, the root
> port does not respond.
> 
> The issue can be reproduced with the following:
> 
> $ sudo phc2sys -R 1000 -O 0 -i tsn0 -m
> 
> Note: 1000 Hz (-R 1000) is unrealistically large, but provides a way to
> quickly reproduce the issue.
> 
> PHC2SYS exits with:
> 
> "ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction
>    fails
> 
> Fixes: 6b8aa753a9f9 ("igc: Decrease PTM short interval from 10 us to 1 us")
> Signed-off-by: Christopher S M Hall <christopher.s.hall at intel.com>
> ---
>   drivers/net/ethernet/intel/igc/igc_defines.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>Tested-by: Avigail Dahan <avigailx.dahan at intel.com>