Re: [PATCH net-next] net/mlx5: Implement swp_l4_csum_mode via devlink params

From: Jiri Pirko
Date: Fri Oct 24 2025 - 04:50:41 EST


Thu, Oct 23, 2025 at 04:34:15PM +0200, daniel.zahka@xxxxxxxxx wrote:
>
>
>On 10/23/25 8:18 AM, Jiri Pirko wrote:
>> Wed, Oct 22, 2025 at 09:09:31PM +0200, daniel.zahka@xxxxxxxxx wrote:
>> > swp_l4_csum_mode controls how L4 transmit checksums are computed when
>> > using Software Parser (SWP) hints for header locations.
>> >
>> > Supported values:
>> > 1. device_default: use device default setting.
>> Is this different between devices/fw_versions?
>
>That is what I presume. I believe the current setting for swp_l4_csum_mode is
>ultimately encoded in the capabilities advertised to the driver during
>initialization. For example, I am mostly interested in mlx5e_psp_init(),
>which depends on:
>
>    if (!MLX5_CAP_ETH(mdev, swp_csum_l4_partial)) {
>        mlx5_core_dbg(mdev, "SWP L4 partial checksum not supported\n");
>        return 0;
>    }
>
>My guess is that "device_default" means that this bit would depend on the
>device/fw_version.

Hmm, I would like to clear the meaning of this before we add it to UAPI.
Asked internally, will let you know.