Re: [PATCH v1 01/16] arm/vpl011: rename virtual PL011 Kconfig option

[dmkhn@xxxxxxxxx]

On Thu, Jul 17, 2025 at 05:43:22PM +0200, Alejandro Vallejo wrote:
> On Tue Jun 24, 2025 at 9:24 AM CEST, dmkhn wrote:
> > On Tue, Jun 24, 2025 at 08:13:08AM +0200, Orzel, Michal wrote:
> >>
> >>
> >> On 24/06/2025 05:55, dmkhn@xxxxxxxxx wrote:
> >> > From: Denis Mukhin <dmukhin@xxxxxxxx>
> >> >
> >> > Rename CONFIG_SBSA_VUART_CONSOLE to CONFIG_HAS_VUART_PL011.
> >> Why? We emulate SBSA UART and not PL011. Despite the similarities (the 
> >> former is
> >> a subset of the latter) they are not the same. I find it confusing and 
> >> drivers
> >> for PL011 might not work with SBSA UART. Also, in the future we may want to
> >> emulate full PL011 in which case it will be even more confusing.
> >
> > That's because the emulator is called vpl011, but yes, it is SBSA UART.
> > I will adjust to SBSA, thanks!
> >
> >>
> >> Also, why HAS_?
> >
> > My understanding is that HAS_ is the desired naming convention throughout 
> > the
> > code (not documented, though), e.g. all Arm UART drivers are gated by 
> > HAS_XXX
> > (e.g. arch/arm/platforms/Kconfig).
> 
> HAS_ is a non-selectable property dependent on the arch. Think HAS_PCI, or
> HAS_EHCI, etc. IOW: HAS_X means "you may implement feature X on this arch",
> which is why some options have X and HAS_X variants, where X is selectable
> while HAS_X is not.

Thanks; I will fix that.

Jan explained the difference here [1] and [2]:
[1] 
https://lore.kernel.org/xen-devel/6d33355c-477f-4ef3-8f17-b7f1dd1164ce@xxxxxxxx/
[2] 
https://lore.kernel.org/xen-devel/a63ac9d5-152e-47b0-8169-bf470611c059@xxxxxxxx/

It's just there's a lot of drivers (UARTs) which are selectable by the user via
HAS_ symbols (drivers/char/Kconfig)

> 
> Cheers,
> Alejandro
>