On 8 November 2016 at 21:06, H. Nikolaus Schaller <hns@goldelico.com> wrote:

- we need to be able to boot from eMMC or the µSD (needs proper control of
the TXS02612 switch (in MLO, U-Boot and Kernel)

Isn't control of that switch handled in hardware by default after reset? Otherwise ROM wouldn't be able to load MLO in the first place.

- we need an MLO/U-Boot/Kernel variant that switches pinmux of the SD interface

That doesn't sound like a problem

- we need a SD shaped hardware adapter to get the JTAG signals to a probe

This, however, is the tricky part. It would have to be custom made since the (already obscure) NIDnT interface is based on micro-SD.

maybe with level-shifters (I don't know)

No need

IMHO this has a high chance to find out in which state the Palmas is.

I don't suppose there's any way to physically access the i²c bus palmas is on? Since that would obviously also allow it to be interrogated.

Matthijs