Subject: Re: [PATCH v3 6/8] ARM: zte: Bring back zx29 UART support

From: Stefan Dösinger <[email-masked]>
Date: Tue, 21 Apr 2026 00:21:51 +0300

Am Montag, 20. April 2026, 16:00:24 Ostafrikanische Zeit schrieben Sie:
> Topic should be prefixed:
> "amba/serial: amba-pl011: ..."

I'll change it

> Interesting with the AMBA pseudo-ID, but I kind of like the idea.

It wasn't my idea. That's - as the description says - the code that was once 
upstream before it got removed in 89d4f98ae90d. This is also why the 
ZX_UART011_* defines still exist.

I re-checked if the device identifies itself in the mmio area in any way, and 
that I maybe got the size wrong - but that was not the case, everything past 
the ZX_UART011_* registers is zero until the next device starts.

> Things without bit 7 set such as ARMs 0x41 and Qualcomms
> 0x51 are kind of cowboy values however. LSI 0xb6 is the only
> vendor actually following the standard.

> You could use 0x7e.

Another idea I considered is using ZTE's 0x8c (assuming that "Microelectronics 
Institute ZTE" is the same ZTE that made the board), but then I would have to 
invent a device number, ideally without clashing with an existing ZTE device.

Thanks for the review,
Stefan