netdev - RE: [PATCH 6/6] can: rcar_canfd: Add has_gerfl_eef to struct rcar_canfd_hw

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 24 Oct 2022 17:46:05 +0000
From:   Biju Das <biju.das.jz@...renesas.com>
To:     Geert Uytterhoeven <geert@...ux-m68k.org>
CC:     Wolfgang Grandegger <wg@...ndegger.com>,
        Marc Kleine-Budde <mkl@...gutronix.de>,
        "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        Vincent Mailhol <mailhol.vincent@...adoo.fr>,
        Stefan Mätje <stefan.maetje@....eu>,
        Ulrich Hecht <uli+renesas@...nd.eu>,
        Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@...renesas.com>,
        Christophe JAILLET <christophe.jaillet@...adoo.fr>,
        "linux-can@...r.kernel.org" <linux-can@...r.kernel.org>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        Chris Paterson <Chris.Paterson2@...esas.com>,
        Biju Das <biju.das@...renesas.com>,
        "linux-renesas-soc@...r.kernel.org" 
        <linux-renesas-soc@...r.kernel.org>
Subject: RE: [PATCH 6/6] can: rcar_canfd: Add has_gerfl_eef to struct
 rcar_canfd_hw_info

Hi Geert,

Thanks for the feedback.

> Subject: Re: [PATCH 6/6] can: rcar_canfd: Add has_gerfl_eef to struct
> rcar_canfd_hw_info
> 
> Hi Biju,
> 
> On Sat, Oct 22, 2022 at 1:03 PM Biju Das <biju.das.jz@...renesas.com>
> wrote:
> > R-Car has ECC error flags in global error interrupts whereas it is
> not
> > available on RZ/G2L.
> >
> > Add has_gerfl_eef to struct rcar_canfd_hw_info so that rcar_canfd_
> > global_error() will process ECC errors only for R-Car.
> >
> > whilst, this patch fixes the below checkpatch warnings
> >   CHECK: Unnecessary parentheses around 'ch == 0'
> >   CHECK: Unnecessary parentheses around 'ch == 1'
> >
> > Signed-off-by: Biju Das <biju.das.jz@...renesas.com>
> 
> Thanks for your patch!
> 
> > --- a/drivers/net/can/rcar/rcar_canfd.c
> > +++ b/drivers/net/can/rcar/rcar_canfd.c
> > @@ -523,6 +523,7 @@ struct rcar_canfd_hw_info {
> >         unsigned multi_global_irqs:1;   /* Has multiple global irqs
> */
> >         unsigned clk_postdiv:1;         /* Has CAN clk post divider
> */
> >         unsigned multi_channel_irqs:1;  /* Has multiple channel irqs
> > */
> > +       unsigned has_gerfl_eef:1;       /* Has ECC Error Flag  */
> 
> Do you really need this flag? According to the RZ/G2L docs, the
> corresponding register bits are always read as zero.

These are reserved bits with 0 value, But it is not documented as ECC Error flag for RZ/G2L.
So just want to be clear it is a hw feature that not supported for RZ/G2L.  

> 
> >  };
> >
> >  /* Channel priv data */
> 
> > @@ -947,17 +950,18 @@ static void rcar_canfd_global_error(struct
> > net_device *ndev)  {
> >         struct rcar_canfd_channel *priv = netdev_priv(ndev);
> >         struct rcar_canfd_global *gpriv = priv->gpriv;
> > +       const struct rcar_canfd_hw_info *info = gpriv->info;
> >         struct net_device_stats *stats = &ndev->stats;
> >         u32 ch = priv->channel;
> >         u32 gerfl, sts;
> >         u32 ridx = ch + RCANFD_RFFIFO_IDX;
> >
> >         gerfl = rcar_canfd_read(priv->base, RCANFD_GERFL);
> > -       if ((gerfl & RCANFD_GERFL_EEF0) && (ch == 0)) {
> > +       if (info->has_gerfl_eef && (gerfl & RCANFD_GERFL_EEF0) && ch
> > + == 0) {
> >                 netdev_dbg(ndev, "Ch0: ECC Error flag\n");
> >                 stats->tx_dropped++;
> >         }
> > -       if ((gerfl & RCANFD_GERFL_EEF1) && (ch == 1)) {
> > +       if (info->has_gerfl_eef && (gerfl & RCANFD_GERFL_EEF1) && ch
> > + == 1) {
> >                 netdev_dbg(ndev, "Ch1: ECC Error flag\n");
> >                 stats->tx_dropped++;
> >         }
> 
> Just wrap both checks inside a single "if (gpriv->info->has_gerfl) {
> ... }"?
> 

OK, cheers,
Biju