Re: [PATCH] mmc: print clock frequency with recognization

[Ulf Hansson]

On Tue, 5 Jul 2022 at 02:18, Seunghui Lee <sh043.lee@xxxxxxxxxxx> 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@xxxxxxxxxxx>
> ---
>  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
>