Re: [PATCH v2 02/15] serial: core: add uart_iotype_mmio/legacy_io helper functions

[Maciej W. Rozycki]

On Thu, 30 Apr 2026, Andy Shevchenko wrote:

> > +bool uart_iotype_legacy_io(enum uart_iotype iotype)
> 
> Why do we use 'legacy'? Still in use in modern CPUs...

 Deprecated in PCIe and not available in numerous systems.  Also actually 
called "legacy" in some serial port datasheets aged ~20 years now.  While 
some contemporary CPUs indeed retain the port I/O address space, it's for 
legacy use anyway, you don't want to rely on it in new designs.

  Maciej