RE: [PATCH net-next v2 6/8] ravb: Add net_features and net_hw_features to struct ravb_hw_info

[Biju Das <biju.das.jz@bp.renesas.com>]

Hi Sergei,

Thanks for the feedback.

> Subject: Re: [PATCH net-next v2 6/8] ravb: Add net_features and
> net_hw_features to struct ravb_hw_info
> 
> On 8/2/21 1:26 PM, Biju Das wrote:
> 
> > On R-Car the checksum calculation on RX frames is done by the E-MAC
> > module, whereas on RZ/G2L it is done by the TOE.
> >
> > TOE calculates the checksum of received frames from E-MAC and outputs
> > it to DMAC. TOE also calculates the checksum of transmission frames
> > from DMAC and outputs it E-MAC.
> >
> > Add net_features and net_hw_features to struct ravb_hw_info, to
> > support subsequent SoCs without any code changes in the ravb_probe
> function.
> >
> > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> > Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> [...]
> > diff --git a/drivers/net/ethernet/renesas/ravb.h
> > b/drivers/net/ethernet/renesas/ravb.h
> > index b765b2b7d9e9..3df813b2e253 100644
> > --- a/drivers/net/ethernet/renesas/ravb.h
> > +++ b/drivers/net/ethernet/renesas/ravb.h
> > @@ -991,6 +991,8 @@ enum ravb_chip_id {  struct ravb_hw_info {
> >  	const char (*gstrings_stats)[ETH_GSTRING_LEN];
> >  	size_t gstrings_size;
> > +	netdev_features_t net_hw_features;
> > +	netdev_features_t net_features;
> 
>    Do we really need both of these here? 

R-Car has only Rx Checksum on E-Mac, where as Geth supports Rx Check Sum on E-Mac or Rx/Tx CheckSum on TOE.
So there is a hw difference. Please let me know what is the best way to handle this?

>It seems like the 'feartures'
> mirrors the enabled features?

Can you please explain this little bit?

> 
> >  	enum ravb_chip_id chip_id;
> >  	int num_gstat_queue;
> >  	int num_tx_desc;
> > diff --git a/drivers/net/ethernet/renesas/ravb_main.c
> > b/drivers/net/ethernet/renesas/ravb_main.c
> > index 7a69668cb512..2ac962b5b8fb 100644
> > --- a/drivers/net/ethernet/renesas/ravb_main.c
> > +++ b/drivers/net/ethernet/renesas/ravb_main.c
> [...]
> > @@ -2077,14 +2081,14 @@ static int ravb_probe(struct platform_device
> *pdev)
> >  	if (!ndev)
> >  		return -ENOMEM;
> >
> > -	ndev->features = NETIF_F_RXCSUM;
> > -	ndev->hw_features = NETIF_F_RXCSUM;
> > +	info = of_device_get_match_data(&pdev->dev);
> > +
> > +	ndev->features = info->net_features;
> > +	ndev->hw_features = info->net_hw_features;
> 
>    What value you plan to set her for GbEth, NETIF_F_HW_CSUM?

Yes, That is the plan.
.net_hw_features = (NETIF_F_HW_CSUM | NETIF_F_RXCSUM),

Regards,
Biju

> 
> [...]
> 
> MBR, Sergei