[PATCH 1/3] efi_loader: print boot device and file path in helloworld

[AKASHI Takahiro <takahiro.akashi@linaro.org>]

On Fri, Jan 15, 2021 at 01:02:51PM +0100, Heinrich Schuchardt wrote:
> On 15.01.21 05:29, AKASHI Takahiro wrote:
> > On Fri, Jan 15, 2021 at 04:12:18AM +0100, Heinrich Schuchardt wrote:
> >> Am 15. Januar 2021 02:56:03 MEZ schrieb AKASHI Takahiro <takahiro.akashi@linaro.org>:
> >>> Heinrich,
> >>>
> >>> On Tue, Jan 12, 2021 at 08:58:40PM +0100, Heinrich Schuchardt wrote:
> >>>> Let helloworld.efi print the device path of the boot device and the
> >>> file
> >>>> path as provided by the loaded image protocol.
> >>>>
> >>>> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
> >>>> ---
> >>>>  lib/efi_loader/helloworld.c | 167
> >>> +++++++++++++++++++++++++++++-------
> 
> <snip />
> 
> >>>
> >>> If this kind of information is quite useful for users, why not add
> >>> that (printing) feature as an option of bootefi (or efidebug)?
> >>> I'm afraid that most users who are irritated as you said won't be able
> >>> to imagine such information be printed by helloworld app.
> >>>
> >>
> >> The file path is written in
> >>
> >> https://github.com/trini/u-boot/blob/master/cmd/bootefi.c#L471
> >>
> >> Device paths are not really user friendly.
> >
> > So why do you want to print such info at helloworld?
> >
> > I guess that, according to your cover letter, you have in your mind
> > some cases where an user may get in trouble relating to the boot device.
> > Right?
> >
> >> So I would not like to write it there.
> >
> > What I meant to suggest is to add an option, -v or -h, to bootefi,
> > which prints verbose (and helpful) information for users to identify a cause.
> > I can easily imagine users may blindly try to add -[v|h] when
> > they see an error message even if they don't know there is such an option:)
> 
> To me helloworld.efi is a tool for a developer to see if an EFI binary
> is correctly invoked.

My point is that most users (developers?) don't intuitively imagine
such information will be printed with helloworld app.

> The normal U-Boot code we want to keep as slim as possible.

(I doubt this in terms of UEFI)

> According to the spec UEFI boots from the ESP and typically there is
> only one. So printing the file path in cmd/bootefi should be enough.

So again,
> > So why do you want to print such info at helloworld?

-Takahiro Akashi


> Best regards
> 
> Heinrich