Re: [PATCH] arm64: dts: ti: k3-am62a7-sk: Disable mmc Schmitt Trigger

[Nishanth Menon <nm@ti.com>]

On 23:57-20260107, Alexander Sverdlin wrote:
> Hi Markus,
> 
> On Tue, 2026-01-06 at 21:25 +0100, Markus Schneider-Pargmann wrote:
> > > I think we would need to discuss this with TI via our FAE, because the change
> > > in question has both been discussed with former FAE and the technical team
> > > behind, and adopted in TI SDK.
> > > 
> > > Or have you already discused this with corresponding TI HW team?
> > > 
> > > Which hardware is affected, is it the official SK-AM62A-LP?
> > > Is MMC2 the SD-card?
> > 
> > I only tested my am62a board on u-boot v2026.01. It is a SK-AM62A-LP.
> > MMC2 is the SD-card and mmc1 in the devicetree.
> 
> just wanted to let you know, I was able to reproduce the problems with SD
> card access via MMC2 under Linux on AM623 with ST enabled.
> 
> We will seek clarification from TI on why this happens, which peripherals
> are affected and what should be the course of actions.


I have passed this up the chain here at TI. What confuses the heck out
of me is this: from an internal email chain I am privy to, i am being
told that "the ST_EN bit in every PADCONFIG register should never be
changed from its power-on default state of 0b1" and the fact that Linux
kernel has been stable with the setting for a long period, So I am
confused why U-Boot would show this instability.. I don't have answers
at the moment. until we clarify the reasoning, I am going to have to
hold off this given that kernel behavior has not regressed that I am
aware of.

-- 
Regards,
Nishanth Menon
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