RE: [RFC/PATCH 05/18] ravb: Exclude gPTP feature support for RZ/G2L

From: Biju Das <biju.das.jz@bp.renesas.com>
To: Sergey Shtylyov <s.shtylyov@omp.ru>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>
Cc: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>,
	Andrew Lunn <andrew@lunn.ch>,
	Sergei Shtylyov <sergei.shtylyov@gmail.com>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Adam Ford <aford173@gmail.com>,
	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-renesas-soc@vger.kernel.org" 
	<linux-renesas-soc@vger.kernel.org>,
	Chris Paterson <Chris.Paterson2@renesas.com>,
	Biju Das <biju.das@bp.renesas.com>
Subject: RE: [RFC/PATCH 05/18] ravb: Exclude gPTP feature support for RZ/G2L
Date: Thu, 23 Sep 2021 19:13:28 +0000	[thread overview]
Message-ID: <OS0PR01MB5922F3EE90E79FDB0703BCEC86A39@OS0PR01MB5922.jpnprd01.prod.outlook.com> (raw)
In-Reply-To: <2b4acd15-4b46-4f63-d9e7-ba1b86311def@omp.ru>

Hi Sergei,

Thanks for the review.

> -----Original Message-----
> From: Sergey Shtylyov <s.shtylyov@omp.ru>
> Sent: 23 September 2021 20:00
> To: Biju Das <biju.das.jz@bp.renesas.com>; David S. Miller
> <davem@davemloft.net>; Jakub Kicinski <kuba@kernel.org>
> Cc: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>;
> Andrew Lunn <andrew@lunn.ch>; Sergei Shtylyov <sergei.shtylyov@gmail.com>;
> Geert Uytterhoeven <geert+renesas@glider.be>; Adam Ford
> <aford173@gmail.com>; Yoshihiro Shimoda
> <yoshihiro.shimoda.uh@renesas.com>; netdev@vger.kernel.org; linux-renesas-
> soc@vger.kernel.org; Chris Paterson <Chris.Paterson2@renesas.com>; Biju
> Das <biju.das@bp.renesas.com>
> Subject: Re: [RFC/PATCH 05/18] ravb: Exclude gPTP feature support for
> RZ/G2L
> 
> On 9/23/21 5:08 PM, Biju Das wrote:
> 
> > R-Car supports gPTP feature whereas RZ/G2L does not support it.
> > This patch excludes gtp feature support for RZ/G2L by enabling no_gptp
> > feature bit.
> >
> > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> >  drivers/net/ethernet/renesas/ravb_main.c | 46
> > ++++++++++++++----------
> >  1 file changed, 28 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/renesas/ravb_main.c
> > b/drivers/net/ethernet/renesas/ravb_main.c
> > index d38fc33a8e93..8663d83507a0 100644
> > --- a/drivers/net/ethernet/renesas/ravb_main.c
> > +++ b/drivers/net/ethernet/renesas/ravb_main.c
> [...]
> > @@ -953,7 +954,7 @@ static irqreturn_t ravb_interrupt(int irq, void
> *dev_id)
> >  	}
> >
> >  	/* gPTP interrupt status summary */
> > -	if (iss & ISS_CGIS) {
> 
>    Isn't this bit always 0 on RZ/G2L?

This CGIM bit(BIT13) which is present on R-Car Gen3 is not present in RZ/G2L. As per the HW manual
BIT13 is reserved bit and read is always 0.

> 
> > +	if (!info->no_gptp && (iss & ISS_CGIS)) {
> >  		ravb_ptp_interrupt(ndev);
> >  		result = IRQ_HANDLED;
> >  	}
> > @@ -1378,6 +1379,7 @@ static int ravb_get_ts_info(struct net_device
> *ndev,
> >  			    struct ethtool_ts_info *info)
> >  {
> >  	struct ravb_private *priv = netdev_priv(ndev);
> > +	const struct ravb_hw_info *hw_info = priv->info;
> >
> >  	info->so_timestamping =
> >  		SOF_TIMESTAMPING_TX_SOFTWARE |
> > @@ -1391,7 +1393,8 @@ static int ravb_get_ts_info(struct net_device
> *ndev,
> >  		(1 << HWTSTAMP_FILTER_NONE) |
> >  		(1 << HWTSTAMP_FILTER_PTP_V2_L2_EVENT) |
> >  		(1 << HWTSTAMP_FILTER_ALL);
> > -	info->phc_index = ptp_clock_index(priv->ptp.clock);
> > +	if (!hw_info->no_gptp)
> > +		info->phc_index = ptp_clock_index(priv->ptp.clock);
> >
> >  	return 0;
> >  }
> > @@ -2116,6 +2119,7 @@ static const struct ravb_hw_info rgeth_hw_info = {
> >  	.emac_init = ravb_rgeth_emac_init,
> >  	.aligned_tx = 1,
> >  	.tx_counters = 1,
> > +	.no_gptp = 1,
> 
>    Mhm, I definitely don't like the way you "extend" the GbEthernet info
> structure. All the applicable flags should be set in the last patch of the
> series, not amidst of it.

According to me, It is clearer with smaller patches like, what we have done with previous 2 patch sets for factorisation.
Please correct me, if any one have different opinion.

Regards,
Biju

> 
> [...]
> 
> MBR, Sergey