Re: [PATCH v3 1/5] xen/char: Default HAS_NS16550 to y only for X86 and ARM

[Jan Beulich <jbeulich@xxxxxxxx>]

On 14.05.2021 20:53, Connor Davis wrote:
> Defaulting to yes only for X86 and ARM reduces the requirements
> for a minimal build when porting new architectures.

While I agree with the statement, ...

> --- a/xen/drivers/char/Kconfig
> +++ b/xen/drivers/char/Kconfig
> @@ -1,6 +1,6 @@
>  config HAS_NS16550
>       bool "NS16550 UART driver" if ARM
> -     default y
> +     default y if (ARM || X86)

... this approach doesn't scale very well. You would likely have
been hesitant to add a, say, 12-way || here if we had this many
architectures already. I think you instead want

 config HAS_NS16550
        bool "NS16550 UART driver" if ARM
+       default n if RISCV
        default y

which then can be adjusted back by another one line change once
the driver code actually builds.

Jan