Re: [PATCH v2 2/2] docs: Document efitextmode command

[Glenn Washburn]

On Tue, 5 Jul 2022 16:01:04 +0200
Daniel Kiper <dkiper@net-space.pl> wrote:

> On Fri, May 13, 2022 at 12:54:12PM -0500, Glenn Washburn wrote:
> > Signed-off-by: Glenn Washburn <development@efficientek.com>
> 
> I think this patch should be merged with patch #1.
> 
> > ---
> >  docs/grub.texi | 26 ++++++++++++++++++++++++++
> >  1 file changed, 26 insertions(+)
> >
> > diff --git a/docs/grub.texi b/docs/grub.texi
> > index 5de94d062..178957096 100644
> > --- a/docs/grub.texi
> > +++ b/docs/grub.texi
> > @@ -4049,6 +4049,7 @@ you forget a command, you can run the command 
> > @command{help}
> >  * distrust::                    Remove a pubkey from trusted keys
> >  * drivemap::                    Map a drive to another
> >  * echo::                        Display a line of text
> > +* efitextmode::                 Set/Get text output mode resolution
> >  * eval::                        Evaluate agruments as GRUB commands
> >  * export::                      Export an environment variable
> >  * false::                       Do nothing, unsuccessfully
> > @@ -4505,6 +4506,31 @@ character will print that character.
> >  @end deffn
> >
> >
> > +@node efitextmode
> > +@subsection efitextmode
> > +
> > +@deffn Command efitextmode [min | max | mode_num]
> 
> s/mode_num/<mode_num>/?
> 
> After some thinking it seems to me this interface is not very convenient.
> My guess is that the same mode may have different <mode_num> on
> different implementations/platforms. I think EFI shell "mode" command
> "col" "row" approach is more universal/reliable. Though I think it makes
> sense to leave min and max as is...

Hmm, not convenient for who? in what scenario? Its more convenient for
someone at a grub prompt and wanting to set the mode (type less numbers
and when switching between modes easier to go to the next higher or
lower mode). It was more convenient for someone to remember which mode
they wanted when they want to put it in a grub config, which can take a
while because the OS generally needs to boot to edit the config.

The only way I can see specifying cols and rows as convenient is for
someone who wants to make sure that they are at a specific textmode
resolution. But what is the use case for that? Its also convenient for
someone reading a grub config file and wanting to know what resolution
is being requested (which may not be the resolution you get, if its not
supported). But again, who needs to do that? And this can be remedied
by a comment in the config file if desired.

How about keeping the mode number usage if one argument is supplied and
adding the cols/rows usage when two numbers are supplied?

Glenn

> > +When used with no arguments displays all available text output modes. The
> > +set mode determines the columns and rows of the text display when in
> > +text mode. An asterisk, @samp{*}, will be at the end of the line of the
> > +currently set mode.
> > +
> > +Otherwise the command only takes a single parameter, which can be
> > +@samp{min}, @samp{max}, or a mode number given by the listing when run
> > +with no arguments. These arguments set the mode to the minimum, maximum,
> > +and particular mode respectively.
> > +
> > +By default GRUB will start in whatever mode the EFI firmware defaults to.
> > +There are firmwares known to set up the default mode such that output
> > +behaves strangely, for example the cursor in the grub shell never reaches
> > +the bottom of the screen or, when typing characters at the prompt,
> > +characters from previous command output are overwritten. Setting the mode
> > +may fix this.
> > +
> > +Note: This command is only available on EFI platforms.
> 
> s/./ and is similar to EFI shell "mode" command./?
> 
> Daniel