Re: [PATCH 1/3] arm64: dts: ti: k3-am62-main: Update OTAP and ITAP delay select

From: Sjoerd Simons
Date: Tue Dec 20 2022 - 08:07:28 EST


Hey Vignesh

On Tue, 2022-12-20 at 16:49 +0530, Vignesh Raghavendra wrote:
>
>
> On 16/12/22 8:06 pm, Sjoerd Simons wrote:
> > From: Nitin Yadav <n-yadav@xxxxxx>
> >
> > UHS Class U1 sd-card are not getting detected due to incorrect
> > OTAP/ITAP delay select values in linux. Update OTAP and ITAP
> > delay select values for various speed modes. For sdhci0, update
> > OTAP delay values for ddr52 & HS200 and add ITAP delay for legacy
> > & mmc-hs. For sdhci1 & sdhci2, update OTAP & ITAP delay select
> > recommended as in RIOT for various speed modes.
> >
> > Signed-off-by: Nitin Yadav <n-yadav@xxxxxx>
> > [cherry-pick from vendor BSP]
> > Signed-off-by: Sjoerd Simons <sjoerd@xxxxxxxxxxxxx>
> > ---
> >
> >  arch/arm64/boot/dts/ti/k3-am62-main.dtsi | 46 ++++++++++++--------
> > ----
> >  1 file changed, 24 insertions(+), 22 deletions(-)
> >
> > diff --git a/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> > b/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> > index 03660476364f..28c250a8d1ec 100644
> > --- a/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> > +++ b/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> > @@ -391,8 +391,10 @@ sdhci0: mmc@fa10000 {
> >                 ti,clkbuf-sel = <0x7>;
> >                 ti,otap-del-sel-legacy = <0x0>;
> >                 ti,otap-del-sel-mmc-hs = <0x0>;
> > -               ti,otap-del-sel-ddr52 = <0x9>;
> > -               ti,otap-del-sel-hs200 = <0x6>;
> > +               ti,otap-del-sel-ddr52 = <0x5>;
> > +               ti,otap-del-sel-hs200 = <0x5>;
> > +               ti,itap-del-sel-legacy = <0xa>;
>
> This is pretty useless without corresponding driver changes
> to pick up ti,itap-del-sel-legacy as well

Right; itap-del-sel-legacy is properly documented in the device-tree
binding and was already previously set ofcourse so i didn't pick up it
needed more driver changes. That said the dtb change itself should
still be valid even if not actually applied.

> https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/commit/drivers/mmc/host/sdhci_am654.c?h=ti-linux-5.10.y&id=93d22fc56007ee13e589debf0d32c8b1d5fdc6d8
> https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/commit/drivers/mmc/host/sdhci_am654.c?h=ti-linux-5.10.y&id=9c878c3dc642f7f1f3ab6ca7f812cd43fe7ed7d8
>
> Could you list that cards affected and fixed by this change?

It's a Collabora branded UHS class 1 (SDR104) card; Matching the commit
message indication given by Nitin. So that in particular i guess, will
have been fixed by the change to the ti,otap-del-sel-sdr104 value for
sdhci1.

For the two patches you highlighted above; Is TI planning to upstream
those as well?


--
Sjoerd Simons
Collabora Ltd.