RE: [RFC/PATCH 12/18] ravb: Add timestamp to struct ravb_hw_info

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

Hi Sergei,

> Subject: RE: [RFC/PATCH 12/18] ravb: Add timestamp to struct ravb_hw_info
> 
> HI Sergei,
> 
> Thanks for the feedback.
> 
> > -----Original Message-----
> > Subject: Re: [RFC/PATCH 12/18] ravb: Add timestamp to struct
> > ravb_hw_info
> >
> > On 9/23/21 5:08 PM, Biju Das wrote:
> >
> > > R-Car AVB-DMAC supports timestamp feature.
> > > Add a timestamp hw feature bit to struct ravb_hw_info to add this
> > > feature only for R-Car.
> > >
> > > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> > > ---
> > >  drivers/net/ethernet/renesas/ravb.h      |  2 +
> > >  drivers/net/ethernet/renesas/ravb_main.c | 68
> > > +++++++++++++++---------
> > >  2 files changed, 45 insertions(+), 25 deletions(-)
> > >
> > > diff --git a/drivers/net/ethernet/renesas/ravb.h
> > > b/drivers/net/ethernet/renesas/ravb.h
> > > index ab4909244276..2505de5d4a28 100644
> > > --- a/drivers/net/ethernet/renesas/ravb.h
> > > +++ b/drivers/net/ethernet/renesas/ravb.h
> > > @@ -1034,6 +1034,7 @@ struct ravb_hw_info {
> > >  	unsigned mii_rgmii_selection:1;	/* E-MAC supports mii/rgmii
> > selection */
> > >  	unsigned half_duplex:1;		/* E-MAC supports half duplex mode */
> > >  	unsigned rx_2k_buffers:1;	/* AVB-DMAC has Max 2K buf size on RX
> > */
> > > +	unsigned timestamp:1;		/* AVB-DMAC has timestamp */
> >
> >    Isn't this a matter of the gPTP support as well, i.e. no separate
> > flag needed?
> 
> Agreed. Previously it is suggested to use timestamp. I will change it to
> as part of gPTP support cases.
> 
> >
> > [...]
> > > @@ -1089,6 +1090,7 @@ struct ravb_private {
> > >  	unsigned int num_tx_desc;	/* TX descriptors per packet */
> > >
> > >  	int duplex;
> > > +	struct ravb_rx_desc *rgeth_rx_ring[NUM_RX_QUEUE];
> >
> >    Strange place to declare this...
> 
> Agreed. This has to be on later patch. Will move it.
> 
> >
> > >
> > >  	const struct ravb_hw_info *info;
> > >  	struct reset_control *rstc;
> > > diff --git a/drivers/net/ethernet/renesas/ravb_main.c
> > > b/drivers/net/ethernet/renesas/ravb_main.c
> > > index 9c0d35f4b221..2c375002ebcb 100644
> > > --- a/drivers/net/ethernet/renesas/ravb_main.c
> > > +++ b/drivers/net/ethernet/renesas/ravb_main.c
> > > @@ -949,11 +949,14 @@ static bool ravb_queue_interrupt(struct
> > > net_device *ndev, int q)
> > >
> > >  static bool ravb_timestamp_interrupt(struct net_device *ndev)  {
> > > +	struct ravb_private *priv = netdev_priv(ndev);
> > > +	const struct ravb_hw_info *info = priv->info;
> > >  	u32 tis = ravb_read(ndev, TIS);
> > >
> > >  	if (tis & TIS_TFUF) {
> > >  		ravb_write(ndev, ~(TIS_TFUF | TIS_RESERVED), TIS);
> > > -		ravb_get_tx_tstamp(ndev);
> > > +		if (info->timestamp)
> > > +			ravb_get_tx_tstamp(ndev);
> >
> >    Shouldn't we just disable TIS.TFUF permanently instead for the
> > non-gPTP case?
> 
> Good catch. As ravb_dmac_init_rgeth(will be renamed to
> "ravb_dmac_init_gbeth") is not enabling this interrupt as it is not
> documented in RZ/G2L hardware manual.
> So this function never gets called for non-gPTP case.
> 
> I will remove this check.


As discussed, I will drop this patch in the next version and contents of this patch will be added to gPTP support cases.

Regards,
Biju