Re: [PATCH v2] mmc: sdhci-acpi: Fix HS400 tuning for AMDI0040

[Ulf Hansson]

On Fri, 21 Aug 2020 at 02:24, Nicolas Boichat <drinkcat@xxxxxxxxxxxx> wrote:
>
> On Thu, Aug 20, 2020 at 3:00 AM Raul E Rangel <rrangel@xxxxxxxxxxxx> wrote:
> >
> > The AMD eMMC Controller can only use the tuned clock while in HS200 and
> > HS400 mode. If we switch to a different mode, we need to disable the
> > tuned clock. If we have previously performed tuning and switch back to
> > HS200 or HS400, we can re-enable the tuned clock.
> >
> > Previously the tuned clock was not getting disabled when switching to
> > DDR52 which is part of the HS400 tuning sequence.
> >
> > Fixes: 34597a3f60b1 ("mmc: sdhci-acpi: Add support for ACPI HID of AMD Controller with HS400")
> > Signed-off-by: Raul E Rangel <rrangel@xxxxxxxxxxxx>
> > Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>

Applied for fixes, by dropping the trace_printk below, thanks!

Kind regards
Uffe


> > ---
> >
> > Changes in v2:
> > - Added static to amd_sdhci_execute_tuning
> >
> >  drivers/mmc/host/sdhci-acpi.c | 68 +++++++++++++++++++++++++++++------
> >  1 file changed, 58 insertions(+), 10 deletions(-)
> [snip]
> > +               /* DLL is only required for HS400 */
> > +               if (host->timing == MMC_TIMING_MMC_HS400 &&
> > +                   !amd_host->dll_enabled) {
> > +                       trace_printk("%s: Enabling DLL\n", __func__);
>
> Please do not use trace_printk in production code [1,2], it is only
> meant for debug use. Consider using dev_dbg.
>
> [1] https://elixir.bootlin.com/linux/v5.8/source/kernel/trace/trace.c#L3158
> [2] https://elixir.bootlin.com/linux/v5.8/source/include/linux/kernel.h#L766
>
> > +                       sdhci_acpi_amd_hs400_dll(host);
> > +                       amd_host->dll_enabled = true;
> > +               }
> >         }