[PATCH v3 0/3] serial: Support a disabled serial port

[Caleb Connolly]

Hi Simon,

On 20/11/2024 16:35, Simon Glass wrote:
> This series provides a way to tell a serial UART that it can't actually
> work, at runtime. The main motivation is to deal with a coreboot feature
> where it does not provide UART details in the sysinfo structure unless
> the UART is also enabled in coreboot.

Why is the UART driver probed if coreboot doesn't provide the necessary
info for it?

Couldn't you disable CONFIG_REQUIRE_SERIAL_CONSOLE and skip probing it?

Kind regards,
> 
> Attempts to introduce a way to enable a silent UART in coreboot have
> lead to a large amount of discussion but no result, sadly.
> 
> This series reworks a patch sent last year, which was not quite ready to
> be applied. A coreboot user (on irc) hit this problem, so it needs to be
> resolved.
> 
> Link: https://patchwork.ozlabs.org/project/uboot/patch/20231101180447.99361-1-sjg@chromium.org/
> 
> Changes in v3:
> - Put the feature behind a Kconfig
> - Move the feature to the serial uclass, so any serial driver can use it
> 
> Changes in v2:
> - Drop RFC tag since there were no comments
> 
> Simon Glass (3):
>   serial: Allow a serial port to be silent disabled
>   serial: ns16550: Avoid probing hardware when disabled
>   x86: coreboot: Make use of disabled console
> 
>  arch/x86/cpu/coreboot/Kconfig    |  1 +
>  drivers/serial/Kconfig           |  9 +++++++++
>  drivers/serial/ns16550.c         |  3 ++-
>  drivers/serial/serial-uclass.c   | 19 ++++++++++++++++++-
>  drivers/serial/serial_coreboot.c |  2 ++
>  include/serial.h                 | 25 +++++++++++++++++++++++++
>  6 files changed, 57 insertions(+), 2 deletions(-)
> 

-- 
// Caleb (they/them)