Re: [PATCH v3 4/6] can: rcar_canfd: Add postdiv to struct rcar_canfd_hw_info

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: biju.das.jz@bp.renesas.com
Cc: "Wolfgang Grandegger" <wg@grandegger.com>,
	"Marc Kleine-Budde" <mkl@pengutronix.de>,
	"David S. Miller" <davem@davemloft.net>,
	"Eric Dumazet" <edumazet@google.com>,
	"Jakub Kicinski" <kuba@kernel.org>,
	"Paolo Abeni" <pabeni@redhat.com>,
	"Vincent Mailhol" <mailhol.vincent@wanadoo.fr>,
	"Stefan Mätje" <stefan.maetje@esd.eu>,
	"Ulrich Hecht" <uli+renesas@fpond.eu>,
	"Lad Prabhakar" <prabhakar.mahadev-lad.rj@bp.renesas.com>,
	"Christophe JAILLET" <christophe.jaillet@wanadoo.fr>,
	linux-can@vger.kernel.org, netdev@vger.kernel.org,
	"Geert Uytterhoeven" <geert+renesas@glider.be>,
	"Chris Paterson" <Chris.Paterson2@renesas.com>,
	"Biju Das" <biju.das@bp.renesas.com>,
	linux-renesas-soc@vger.kernel.org
Subject: Re: [PATCH v3 4/6] can: rcar_canfd: Add postdiv to struct rcar_canfd_hw_info
Date: Fri, 28 Oct 2022 11:31:21 +0200	[thread overview]
Message-ID: <CAMuHMdVf8R8JHM8jay2LiGGb8gLn1W0N8Q901ADcaNWv4hmAvQ@mail.gmail.com> (raw)
In-Reply-To: <20221027082158.95895-5-biju.das.jz@bp.renesas.com>

Hi Biju,

On Thu, Oct 27, 2022 at 10:22 AM Biju Das <biju.das.jz@bp.renesas.com> wrote:
> R-Car has a clock divider for CAN FD clock within the IP, whereas
> it is not available on RZ/G2L.
>
> Add postdiv variable to struct rcar_canfd_hw_info to take care of this
> difference.
>
> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v2->v3:
>  * Replaced data type of postdiv from unsigned int->u8 to save memory.

Thanks for the update!

> --- a/drivers/net/can/rcar/rcar_canfd.c
> +++ b/drivers/net/can/rcar/rcar_canfd.c
> @@ -1943,9 +1947,9 @@ static int rcar_canfd_probe(struct platform_device *pdev)
>         }
>         fcan_freq = clk_get_rate(gpriv->can_clk);
>
> -       if (gpriv->fcan == RCANFD_CANFDCLK && info->chip_id != RENESAS_RZG2L)
> +       if (gpriv->fcan == RCANFD_CANFDCLK)
>                 /* CANFD clock is further divided by (1/2) within the IP */

may be further divided?

> -               fcan_freq /= 2;
> +               fcan_freq /= info->postdiv;
>
>         addr = devm_platform_ioremap_resource(pdev, 0);
>         if (IS_ERR(addr)) {

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds