Re: [PATCH] drivers: net: gianfar: Shortest frame drops at Ethernet port

From: Daniel Walker
Date: Wed Nov 06 2019 - 12:46:10 EST


On Wed, Nov 06, 2019 at 05:38:06PM +0000, Claudiu Manoil wrote:
> >-----Original Message-----
> >From: Daniel Walker <danielwa@xxxxxxxxx>
> >Sent: Wednesday, November 6, 2019 7:03 PM
> >To: Claudiu Manoil <claudiu.manoil@xxxxxxx>
> >Cc: Sathish Jarugumalli <sjarugum@xxxxxxxxx>; xe-linux-external@xxxxxxxxx;
> >Daniel Walker <dwalker@xxxxxxxxxx>; David S. Miller
> ><davem@xxxxxxxxxxxxx>; netdev@xxxxxxxxxxxxxxx; linux-
> >kernel@xxxxxxxxxxxxxxx
> >Subject: [PATCH] drivers: net: gianfar: Shortest frame drops at Ethernet port
> >
> >NXP has provided the patch for packet drops at ethernet port
> >Frames shorter than 60bytes are getting dropped at ethernetport
> >need to add padding for the shorter range frames to be transmit
> >the function "eth_skb_pad(skb" provides padding (and CRC) for
> >packets under 60 bytes
> >
> >Signed-off-by: Sathish Jarugumalli <sjarugum@xxxxxxxxx>
> >Cc: xe-linux-external@xxxxxxxxx
> >Signed-off-by: Daniel Walker <dwalker@xxxxxxxxxx>
>
> Signed-off-by: Claudiu Manoil <claudiu.manoil@xxxxxxx>
>
> Normally padding is done by the hardware, and it works at least on my
> test cases and boards.
> But cisco seems to have hit a case where h/w padding gets
> unexpectedly disabled (concurrency issue writing the config register?).
> This patch should go as a workaround, until root cause found.


Where would this hardware setup normally happen? Does it happen in the
bootloader or inside the kernel someplace ?

Daniel