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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260108164024.fodfklk7xayh4dqj@authentic>
Date: Thu, 8 Jan 2026 10:40:24 -0600
From: Nishanth Menon <nm@...com>
To: Alexander Sverdlin <alexander.sverdlin@...il.com>
CC: Markus Schneider-Pargmann <msp@...libre.com>, Vignesh Raghavendra
	<vigneshr@...com>, Tero Kristo <kristo@...nel.org>, Rob Herring
	<robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley
	<conor+dt@...nel.org>, Vishal Mahaveer <vishalm@...com>, Kevin Hilman
	<khilman@...libre.com>, Dhruva Gole <d-gole@...com>, Sebin Francis
	<sebin.francis@...com>, Kendall Willis <k-willis@...com>, Akashdeep Kaur
	<a-kaur@...com>, <linux-arm-kernel@...ts.infradead.org>,
	<devicetree@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] arm64: dts: ti: k3-am62a7-sk: Disable mmc Schmitt Trigger

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
Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3  1A34 DDB5 849D 1736 249D
https://ti.com/opensource