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

Markus Schneider-Pargmann msp at baylibre.com
Thu Jan 8 11:04:44 PST 2026


Hi Alexander,

On Wed Jan 7, 2026 at 3:49 PM CET, Alexander Sverdlin wrote:
> Hi Markus,
>
> On Tue, 2026-01-06 at 18:25 +0100, Alexander Sverdlin wrote:
>> >  	main_mmc1_pins_default: main-mmc1-default-pins {
>> >  		pinctrl-single,pins = <
>> > -			AM62AX_IOPAD(0x23c, PIN_INPUT, 0) /* (A21) MMC1_CMD */
>
> this is a bit trial-and-error, but maybe you could try to add missing clock
> retimer/loopback pin for test instead of disabling ST? Would this help:
>
> 			AM62AX_IOPAD(0x238, PIN_INPUT, 0) /* (N/A) MMC1_CLKLB */
>
> some SoCs from AM6x family seem to require it even though TRMs claim the default
> PoR state is the proper one.

Thanks, but adding that does not help unfortunately. And it seems ST
being enabled on that pin does not break it either. The data lines seem
to be the important ones.

Best
Markus

>
>> > -			AM62AX_IOPAD(0x234, PIN_INPUT, 0) /* (B22) MMC1_CLK */
>> > -			AM62AX_IOPAD(0x230, PIN_INPUT, 0) /* (A22) MMC1_DAT0 */
>> > -			AM62AX_IOPAD(0x22c, PIN_INPUT, 0) /* (B21) MMC1_DAT1 */
>> > -			AM62AX_IOPAD(0x228, PIN_INPUT, 0) /* (C21) MMC1_DAT2 */
>> > -			AM62AX_IOPAD(0x224, PIN_INPUT, 0) /* (D22) MMC1_DAT3 */
>> > -			AM62AX_IOPAD(0x240, PIN_INPUT, 0) /* (D17) MMC1_SDCD */
>> 
>> All of these have ST enabled on PoR, according to TRM.
>> 
>> > +			AM62AX_IOPAD(0x23c, PIN_INPUT_NOST, 0) /* (A21) MMC1_CMD */
>> > +			AM62AX_IOPAD(0x234, PIN_INPUT_NOST, 0) /* (B22) MMC1_CLK */
>> > +			AM62AX_IOPAD(0x230, PIN_INPUT_NOST, 0) /* (A22) MMC1_DAT0 */
>> > +			AM62AX_IOPAD(0x22c, PIN_INPUT_NOST, 0) /* (B21) MMC1_DAT1 */
>> > +			AM62AX_IOPAD(0x228, PIN_INPUT_NOST, 0) /* (C21) MMC1_DAT2 */
>> > +			AM62AX_IOPAD(0x224, PIN_INPUT_NOST, 0) /* (D22) MMC1_DAT3 */
>> > +			AM62AX_IOPAD(0x240, PIN_INPUT_NOST, 0) /* (D17) MMC1_SDCD */
>> >  		>;
>> >  		bootph-all;
>> >  	};

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 289 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20260108/36614615/attachment-0001.sig>


More information about the linux-arm-kernel mailing list