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

[Heinrich Schuchardt]

On 11/7/22 18:32, Simon Glass wrote:
> 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.

Yes, you reviewed patch a085aa1f2737 ("dm: video: Add basic ANSI escape
sequence support") exactly for this purpose.

Both CI tests on QEMU and sandbox pass. It is good that the CI sees
exactly the same output as a productive system. We should not change that.

Best regards

Heinrich