> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf
> Of Chwee-Lin Choong
> Sent: Tuesday, December 2, 2025 1:24 PM
> To: Nguyen, Anthony L <[email protected]>; Kitszel,
> Przemyslaw <[email protected]>; Andrew Lunn
> <[email protected]>; David S . Miller <[email protected]>; Eric
> Dumazet <[email protected]>; Jakub Kicinski <[email protected]>; Paolo
> Abeni <[email protected]>
> Cc: [email protected]; [email protected]; linux-
> [email protected]; Bouska; Bouska, Zdenek
> <[email protected]>; Faizal Rahim
> <[email protected]>
> Subject: [Intel-wired-lan] [PATCH iwl-net v1] igc: Use 5KB TX packet
> buffer per queue for TSN mode
>
> Update IGC_TXPBSIZE_TSN to allocate 5KB per TX queue (TXQ0-TXQ3) as
> recommended in I225/I226 SW User Manual Section 7.5.4 for TSN
> operation.
>
> Fixes: 0d58cdc902da ("igc: optimize TX packet buffer utilization for
> TSN mode")
> Reported-by: Bouska, Zdenek <[email protected]>
> Closes:
> https://lore.kernel.org/netdev/AS1PR10MB5675DBFE7CE5F2A9336ABFA4EBEAA@
> AS1PR10MB5675.EURPRD10.PROD.OUTLOOK.COM/
> Signed-off-by: Chwee-Lin Choong <[email protected]>
> ---
> drivers/net/ethernet/intel/igc/igc_defines.h | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h
> b/drivers/net/ethernet/intel/igc/igc_defines.h
> index 498ba1522ca4..9482ab11f050 100644
> --- a/drivers/net/ethernet/intel/igc/igc_defines.h
> +++ b/drivers/net/ethernet/intel/igc/igc_defines.h
> @@ -443,9 +443,10 @@
> #define IGC_TXPBSIZE_DEFAULT ( \
> IGC_TXPB0SIZE(20) | IGC_TXPB1SIZE(0) | IGC_TXPB2SIZE(0) | \
> IGC_TXPB3SIZE(0) | IGC_OS2BMCPBSIZE(4))
> +/* TSN value following I225/I226 SW User Manual Section 7.5.4 */
> #define IGC_TXPBSIZE_TSN ( \
> - IGC_TXPB0SIZE(7) | IGC_TXPB1SIZE(7) | IGC_TXPB2SIZE(7) | \
> - IGC_TXPB3SIZE(7) | IGC_OS2BMCPBSIZE(4))
> + IGC_TXPB0SIZE(5) | IGC_TXPB1SIZE(5) | IGC_TXPB2SIZE(5) | \
> + IGC_TXPB3SIZE(5) | IGC_OS2BMCPBSIZE(4))
>
> #define IGC_DTXMXPKTSZ_TSN 0x19 /* 1600 bytes of max TX DMA packet
> size */
> #define IGC_DTXMXPKTSZ_DEFAULT 0x98 /* 9728-byte Jumbo frames */
> --
> 2.43.0
Reviewed-by: Aleksandr Loktionov <[email protected]>
