RE: [PATCH net-next 4/5] net: ravb: Do not apply RX checksum settings to hardware if the interface is down

From: Biju Das
Date: Thu Feb 08 2024 - 03:10:00 EST


Hi Sergey,

> -----Original Message-----
> From: Sergey Shtylyov <s.shtylyov@xxxxxx>
> Sent: Wednesday, February 7, 2024 8:50 PM
> Subject: Re: [PATCH net-next 4/5] net: ravb: Do not apply RX checksum
> settings to hardware if the interface is down
>
> On 2/7/24 3:07 PM, Claudiu wrote:
>
> > From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
> >
> > Do not apply the RX checksum settings to hardware if the interface is
> down.
> > In case runtime PM is enabled, and while the interface is down, the IP
> > will be in reset mode (as for some platforms disabling the clocks will
> > switch the IP to reset mode, which will lead to losing registers
> > content) and
>
> The register contents? I thought I'd pointed out all of these...
>
> > applying settings in reset mode is not an option. Instead, cache the
> > RX checksum settings and apply them in ravb_open() through
> ravb_emac_init().
> > This has been solved by introducing pm_runtime_active() check. The
> > device runtime PM usage counter has been incremented to avoid
> > disabling the device clocks while the check is in progress (if any).
> >
> > Commit prepares for the addition of runtime PM.
> >
> > Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>
> Reviewed-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
>
> I'm afraid such check now needs to be added to
> ravb_set_features_gbeth() that's populated by Biju Das' checksum patches
> (which I've already ACKed)...

You mean this check to be moved to ravb_set_features_rcar() instead of ravb_set_rx_csum()
as ravb_set_rx_csum() is called in receive path as well which is interface up case.
ON reset mode, anyway we don't get any interrupts so there is no rx.
Then possibility is through set_features??

Cheers,
Biju