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 <20220705005035.14195-1-sh043.lee@samsung.com>
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From:   Ulf Hansson <ulf.hansson@linaro.org>
Date:   Tue, 12 Jul 2022 12:51:29 +0200
Message-ID: <CAPDyKFqzVJ+EQYZWJG3adYEWdr=9kAXunwyKESvWqT8-L84Q9w@mail.gmail.com>
Subject: Re: [PATCH] mmc: print clock frequency with recognization
To:     Seunghui Lee <sh043.lee@samsung.com>
Cc:     u.kleine-koenig@pengutronix.de, gregkh@linuxfoundation.org,
        linux@dominikbrodowski.net, alexandre.belloni@bootlin.com,
        linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
        grant.jung@samsung.com, jt77.jang@samsung.com,
        dh0421.hwang@samsung.com, junwoo80.lee@samsung.com,
        jangsub.yi@samsung.com, cw9316.lee@samsung.com,
        sh8267.baek@samsung.com, wkon.kim@samsung.com,
        seunghwan.hyun@samsung.com
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On Tue, 5 Jul 2022 at 02:18, Seunghui Lee <sh043.lee@samsung.com> wrote:
>
> It's easy to figure out how fast frequency it has from the log.
> e.g. mmc0: new ultra high speed SDR104 SDXC card
> at address aaaa(clk 202000000)

Well, this information is already available through debugfs and I
think that is sufficient.

Moreover, card->host->ios.clock doesn't necessarily contain that
actual clock rate, but rather the rate that is requested by the core.
To really know the rate the bus is running on,
card->host->ios.actual_clock needs to be checked too. This too is
available through debugfs.

Kind regards
Uffe

>
> Signed-off-by: Seunghui Lee <sh043.lee@samsung.com>
> ---
>  drivers/mmc/core/bus.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c
> index 58a60afa650b..3623cc27a61c 100644
> --- a/drivers/mmc/core/bus.c
> +++ b/drivers/mmc/core/bus.c
> @@ -348,7 +348,7 @@ int mmc_add_card(struct mmc_card *card)
>                         mmc_card_ddr52(card) ? "DDR " : "",
>                         type);
>         } else {
> -               pr_info("%s: new %s%s%s%s%s%s card at address %04x\n",
> +               pr_info("%s: new %s%s%s%s%s%s card at address %04x(clk %u)\n",
>                         mmc_hostname(card->host),
>                         mmc_card_uhs(card) ? "ultra high speed " :
>                         (mmc_card_hs(card) ? "high speed " : ""),
> @@ -356,7 +356,8 @@ int mmc_add_card(struct mmc_card *card)
>                         (mmc_card_hs200(card) ? "HS200 " : ""),
>                         mmc_card_hs400es(card) ? "Enhanced strobe " : "",
>                         mmc_card_ddr52(card) ? "DDR " : "",
> -                       uhs_bus_speed_mode, type, card->rca);
> +                       uhs_bus_speed_mode, type, card->rca,
> +                       card->host->ios.clock);
>         }
>
>  #ifdef CONFIG_DEBUG_FS
> --
> 2.29.0
>