[PATCH v3 1/3] efi_loader: Avoid overwriting previous outputs on console screen clearing

[Simon Glass]

Hi Heinrich,

On Mon, 7 Nov 2022 at 09:18, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
> On 11/7/22 16:28, Simon Glass wrote:
> > Hi Jan,
> >
> > On Mon, 7 Nov 2022 at 06:50, Jan Kiszka <jan.kiszka at siemens.com> wrote:
> >>
> >> On 04.11.22 20:08, Simon Glass wrote:
> >>> Hi,
> >>>
> >>> On Fri, 4 Nov 2022 at 02:07, Jan Kiszka <jan.kiszka at siemens.com> wrote:
> >>>>
> >>>> From: Jan Kiszka <jan.kiszka at siemens.com>
> >>>>
> >>>> Before clearing the screen, ensure that no previous output of firmware
> >>>> or UEFI programs will be overwritten on serial devices or other
> >>>> streaming consoles. This helps generating complete boot logs.
> >>>>
> >>>> Tested regarding multi-output against qemu-x86_defconfig.
> >>>>
> >>>> Signed-off-by: Jan Kiszka <jan.kiszka at siemens.com>
> >>>> ---
> >>>>   lib/efi_loader/efi_console.c | 8 +++++++-
> >>>>   1 file changed, 7 insertions(+), 1 deletion(-)
> >>>
> >>> Please see this thread...some things need to be improved in this area.
> >>>
> >>> https://patchwork.ozlabs.org/project/uboot/patch/20221022092058.106052-1-heinrich.schuchardt@canonical.com/
> >>>
> >>
> >> Is there a conclusion already? Is there something that I can attach to
> >> to resolve this issue here?
> >
> > So far as I am concerned, there is a conclusion :) I provided a lot of
> > detail in the thread linked above.
>
> Simon, if you want to filter output on the sandbox you may do so in the
> serial driver of the sandbox. It is not related to the UEFI code.

>From what I can tell this problem also affects the qemu CI tests. It
seems that UEFI needs ANSI so this appears to be a UEFI thing. I
haven't actually noticed any other use of ANSI sequences in some years
of using U-Boot.

Regards,
Simon