Re: [PATCH v2 09/10] clk: renesas: r9a08g045: Add the RZG2L_PD_F_CONSOLE flag to scif0 PM domain

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Claudiu <claudiu.beznea@tuxon.dev>
Cc: mturquette@baylibre.com, sboyd@kernel.org, robh@kernel.org,
	 krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
	magnus.damm@gmail.com,  linux-renesas-soc@vger.kernel.org,
	linux-clk@vger.kernel.org,  devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	 Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Subject: Re: [PATCH v2 09/10] clk: renesas: r9a08g045: Add the RZG2L_PD_F_CONSOLE flag to scif0 PM domain
Date: Thu, 14 Mar 2024 17:06:52 +0100	[thread overview]
Message-ID: <CAMuHMdXJtBNBqitJ3-5zC9JAJSZvP+4-9wOK9p8OO-OR42dUqQ@mail.gmail.com> (raw)
In-Reply-To: <20240307140728.190184-10-claudiu.beznea.uj@bp.renesas.com>

Hi Claudiu,

On Thu, Mar 7, 2024 at 3:08 PM Claudiu <claudiu.beznea@tuxon.dev> wrote:
> From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
>
> The RZG2L_PD_F_CONSOLE is used by the rzg2l-cpg driver to check if the
> SCIF domain need to be powered off in suspend. This is necessary when
> no_console_suspend is available in bootargs as we want to still see
> output on console, thus scif0 domain should remain powered on.
>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

Thanks for your patch!

> --- a/drivers/clk/renesas/r9a08g045-cpg.c
> +++ b/drivers/clk/renesas/r9a08g045-cpg.c
> @@ -293,7 +293,7 @@ static const struct rzg2l_cpg_pm_domain_init_data r9a08g045_pm_domains[] = {
>         DEF_PD("scif0",         R9A08G045_PD_SCIF0,
>                                 DEF_REG_CONF(CPG_BUS_MCPU2_MSTOP, BIT(1)),
>                                 DEF_REG_CONF(0, 0),
> -                               RZG2L_PD_F_NONE),
> +                               RZG2L_PD_F_CONSOLE),

This is not really correct: if SCIF0 is used as the console depends on the
use case, i.e. on chosen/stdout-path.
So this flag should be set at run-time. You can check the power-domains
property of the node pointed to by of_stdout to find the PM Domain that
holds the console, cfr. drivers/pmdomain/renesas/rmobile-sysc.c.

>  };
>
>  const struct rzg2l_cpg_info r9a08g045_cpg_info = {

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