RE: [EXT] Re: [net-next PATCH 3/7] octeontx2-pf: ethtool fec mode support

[Hariprasad Kelam]

Hi Jakub,

> -----Original Message-----
> From: Jakub Kicinski <kuba@xxxxxxxxxx>
> Sent: Saturday, January 23, 2021 10:00 AM
> To: Hariprasad Kelam <hkelam@xxxxxxxxxxx>
> Cc: netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> davem@xxxxxxxxxxxxx; Sunil Kovvuri Goutham <sgoutham@xxxxxxxxxxx>;
> Linu Cherian <lcherian@xxxxxxxxxxx>; Geethasowjanya Akula
> <gakula@xxxxxxxxxxx>; Jerin Jacob Kollanukkaran <jerinj@xxxxxxxxxxx>;
> Subbaraya Sundeep Bhatta <sbhatta@xxxxxxxxxxx>; Christina Jacob
> <cjacob@xxxxxxxxxxx>
> Subject: [EXT] Re: [net-next PATCH 3/7] octeontx2-pf: ethtool fec mode
> support
> 
> External Email
> 
> ----------------------------------------------------------------------
> On Thu, 21 Jan 2021 13:23:25 +0530 Hariprasad Kelam wrote:
> > From: Christina Jacob <cjacob@xxxxxxxxxxx>
> >
> > Add ethtool support to configure fec modes baser/rs and support to
> > fecth FEC stats from CGX as well PHY.
> >
> > Configure fec mode
> > 	- ethtool --set-fec eth0 encoding rs/baser/off/auto Query fec mode
> > 	- ethtool --show-fec eth0
> >
> > Signed-off-by: Christina Jacob <cjacob@xxxxxxxxxxx>
> > Signed-off-by: Sunil Goutham <sgoutham@xxxxxxxxxxx>
> > Signed-off-by: Hariprasad Kelam <hkelam@xxxxxxxxxxx>
> > ---
> >  .../ethernet/marvell/octeontx2/nic/otx2_common.c   |  23 +++
> >  .../ethernet/marvell/octeontx2/nic/otx2_common.h   |   6 +
> >  .../ethernet/marvell/octeontx2/nic/otx2_ethtool.c  | 174
> ++++++++++++++++++++-
> >  .../net/ethernet/marvell/octeontx2/nic/otx2_pf.c   |   3 +
> >  4 files changed, 204 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
> > b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
> > index bdfa2e2..d09119b 100644
> > --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
> > +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
> > @@ -60,6 +60,22 @@ void otx2_update_lmac_stats(struct otx2_nic *pfvf)
> >  	mutex_unlock(&pfvf->mbox.lock);
> >  }
> >
> > +void otx2_update_lmac_fec_stats(struct otx2_nic *pfvf) {
> > +	struct msg_req *req;
> > +
> > +	if (!netif_running(pfvf->netdev))
> > +		return;
> > +	mutex_lock(&pfvf->mbox.lock);
> > +	req = otx2_mbox_alloc_msg_cgx_fec_stats(&pfvf->mbox);
> > +	if (!req) {
> > +		mutex_unlock(&pfvf->mbox.lock);
> > +		return;
> > +	}
> > +	otx2_sync_mbox_msg(&pfvf->mbox);
> > +	mutex_unlock(&pfvf->mbox.lock);
> > +}
> > +
> >  int otx2_update_rq_stats(struct otx2_nic *pfvf, int qidx)  {
> >  	struct otx2_rcv_queue *rq = &pfvf->qset.rq[qidx]; @@ -1491,6
> > +1507,13 @@ void mbox_handler_cgx_stats(struct otx2_nic *pfvf,
> >  		pfvf->hw.cgx_tx_stats[id] = rsp->tx_stats[id];  }
> >
> > +void mbox_handler_cgx_fec_stats(struct otx2_nic *pfvf,
> > +				struct cgx_fec_stats_rsp *rsp)
> > +{
> > +		pfvf->hw.cgx_fec_corr_blks += rsp->fec_corr_blks;
> > +		pfvf->hw.cgx_fec_uncorr_blks += rsp->fec_uncorr_blks;
> 
> double indented
> 
I will fix this in V2.
> > +}
> > +
> >  void mbox_handler_nix_txsch_alloc(struct otx2_nic *pf,
> >  				  struct nix_txsch_alloc_rsp *rsp)  {
> 
> > @@ -183,12 +210,42 @@ static void otx2_get_ethtool_stats(struct
> net_device *netdev,
> >  	for (stat = 0; stat < CGX_TX_STATS_COUNT; stat++)
> >  		*(data++) = pfvf->hw.cgx_tx_stats[stat];
> >  	*(data++) = pfvf->reset_count;
> > +
> > +	if (pfvf->linfo.fec == OTX2_FEC_NONE)
> > +		return;
> 
> Don't hide the stats based on configuration.
> Getting number of stats and requesting them are two different syscalls.
> 
Agreed .  While getting number of stats also  , check is there to ensure interface 
Has valid fec mode. 
	if (pfvf->linfo.fec) {
                sprintf(data, "Fec Corrected Errors: ");
These checks ensures number of stats and request them are in sync.

> > +	fec_corr_blks = pfvf->hw.cgx_fec_corr_blks;
> > +	fec_uncorr_blks = pfvf->hw.cgx_fec_uncorr_blks;
> > +
> > +	rsp = otx2_get_fwdata(pfvf);
> > +	if (!IS_ERR(rsp) && rsp->fwdata.phy.misc.has_fec_stats &&
> > +	    !otx2_get_phy_fec_stats(pfvf)) {
> > +		/* Fetch fwdata again because it's been recently populated
> with
> > +		 * latest PHY FEC stats.
> > +		 */
> > +		rsp = otx2_get_fwdata(pfvf);
> > +		if (!IS_ERR(rsp)) {
> > +			struct fec_stats_s *p = &rsp->fwdata.phy.fec_stats;
> > +
> > +			if (pfvf->linfo.fec == OTX2_FEC_BASER) {
> > +				fec_corr_blks   = p->brfec_corr_blks;
> > +				fec_uncorr_blks = p->brfec_uncorr_blks;
> > +			} else {
> > +				fec_corr_blks   = p->rsfec_corr_cws;
> > +				fec_uncorr_blks = p->rsfec_uncorr_cws;
> > +			}
> > +		}
> > +	}
> > +
> > +	*(data++) = fec_corr_blks;
> > +	*(data++) = fec_uncorr_blks;
> >  }
> 
> > +static int otx2_get_fecparam(struct net_device *netdev,
> > +			     struct ethtool_fecparam *fecparam) {
> > +	struct otx2_nic *pfvf = netdev_priv(netdev);
> > +	struct cgx_fw_data *rsp;
> > +	int fec[] = {
> 
> const
>
Will fix in V2.
 
> > +		ETHTOOL_FEC_OFF,
> > +		ETHTOOL_FEC_BASER,
> > +		ETHTOOL_FEC_RS,
> > +		ETHTOOL_FEC_BASER | ETHTOOL_FEC_RS}; #define
> FEC_MAX_INDEX 3
> > +	if (pfvf->linfo.fec < FEC_MAX_INDEX)
> > +		fecparam->active_fec = fec[pfvf->linfo.fec];
> > +
> > +	rsp = otx2_get_fwdata(pfvf);
> > +	if (IS_ERR(rsp))
> > +		return PTR_ERR(rsp);
> > +
> > +	if (rsp->fwdata.supported_fec <= FEC_MAX_INDEX) {
> > +		if (!rsp->fwdata.supported_fec)
> > +			fecparam->fec = ETHTOOL_FEC_NONE;
> > +		else
> > +			fecparam->fec = fec[rsp->fwdata.supported_fec];
> > +	}
> > +	return 0;
> > +}
> > +
> > +static int otx2_set_fecparam(struct net_device *netdev,
> > +			     struct ethtool_fecparam *fecparam) {
> > +	struct otx2_nic *pfvf = netdev_priv(netdev);
> > +	struct mbox *mbox = &pfvf->mbox;
> > +	struct fec_mode *req, *rsp;
> > +	int err = 0, fec = 0;
> > +
> > +	switch (fecparam->fec) {
> > +	case ETHTOOL_FEC_OFF:
> > +		fec = OTX2_FEC_NONE;
> > +		break;
> > +	case ETHTOOL_FEC_RS:
> > +		fec = OTX2_FEC_RS;
> > +		break;
> > +	case ETHTOOL_FEC_BASER:
> > +		fec = OTX2_FEC_BASER;
> > +		break;
> > +	default:
> > +		fec = OTX2_FEC_NONE;
> 
> IIRC fecparam->fec is a bitmask, you can't assume other than one bit set is
> NONE.
Agreed . Will fix in V2.
> 
> > +		break;
> > +	}
> > +
> > +	if (fec == pfvf->linfo.fec)
> > +		return 0;
> > +
> > +	mutex_lock(&mbox->lock);
> > +	req = otx2_mbox_alloc_msg_cgx_set_fec_param(&pfvf->mbox);
> > +	if (!req) {
> > +		err = -EAGAIN;
> 
> Why -EAGAIN? When does msg allocation fail?
> 
Agreed . Message allocation fails incase No memory. Will fix this in V2.
> > +		goto end;
> > +	}
> > +	req->fec = fec;
> > +	err = otx2_sync_mbox_msg(&pfvf->mbox);
> > +	if (err)
> > +		goto end;
> > +
> > +	rsp = (struct fec_mode *)otx2_mbox_get_rsp(&pfvf->mbox.mbox,
> > +						   0, &req->hdr);
> > +	if (rsp->fec >= 0) {
> > +		pfvf->linfo.fec = rsp->fec;
> > +		pfvf->hw.cgx_fec_corr_blks = 0;
> > +		pfvf->hw.cgx_fec_uncorr_blks = 0;
> 
> Are you clearing stats every time FEC changes?
> 
Netdev driver gets fec stats from firmware. When user changes fec mode , counters local
To netdev driver becomes stale. So clearing fec counters.
> > +
> 
> spurious new line
> 
Will fix in v2.
> > +	} else {
> > +		err = rsp->fec;
> > +	}
> > +
> > +end:	mutex_unlock(&mbox->lock);
> 
> label on a separate line
> 
Will fix in v2.

Thanks,
Hariprasad k
> > +	return err;
> > +}