Re: [PATCH] powerpc: Use shared font data

From: Dr. David Alan Gilbert
Date: Wed Aug 02 2023 - 12:44:13 EST


* Randy Dunlap (rdunlap@xxxxxxxxxxxxx) wrote:
>
>
> On 8/2/23 05:19, Michael Ellerman wrote:
> > "Dr. David Alan Gilbert" <linux@xxxxxxxxxxx> writes:
> >> * Michael Ellerman (mpe@xxxxxxxxxxxxxx) wrote:
> >>> linux@xxxxxxxxxxx writes:
> >>>> From: "Dr. David Alan Gilbert" <linux@xxxxxxxxxxx>
> >>>>
> >>>> PowerPC has a 'btext' font used for the console which is almost identical
> >>>> to the shared font_sun8x16, so use it rather than duplicating the data.
> >>>>
> >>>> They were actually identical until about a decade ago when
> >>>> commit bcfbeecea11c ("drivers: console: font_: Change a glyph from
> >>>> "broken bar" to "vertical line"")
> >>>>
> >>>> which changed the | in the shared font to be a solid
> >>>> bar rather than a broken bar. That's the only difference.
> >>>>
> >>>> This was originally spotted by PMD which noticed that sparc does
> >>>
> >>> PMD means "Page Middle Directory" to most Linux folks, I assume that's
> >>> not what you meant :)
> >>
> >> Ah, any good TLA is ripe for reuse:
> >> https://pmd.github.io/pmd/pmd_userdocs_cpd.html
> >
> > Thanks.
> >
> > Unfortunately this patch causes a warning:
> >
> > WARNING: unmet direct dependencies detected for FONT_SUN8x16
> > Depends on [n]: FONT_SUPPORT [=y] && FRAMEBUFFER_CONSOLE [=y] && (!SPARC && FONTS [=n] || SPARC)
> > Selected by [y]:
> > - BOOTX_TEXT [=y] && PPC_BOOK3S [=y]
> >
> > And breaks allmodconfig with:
> >
> > ld: arch/powerpc/kernel/btext.o:(.toc+0x0): undefined reference to `font_sun_8x16'
> > make[3]: *** [../scripts/Makefile.vmlinux:36: vmlinux] Error 1
> >
> > I guess the Kconfig logic needs some more work.
>
> Also please see:
> https://lore.kernel.org/all/dd29e5f5-d9f7-0103-e602-b98f26c88fb1@xxxxxxxxxxxxx/
> for a similar problem on UML.

Thanks Michael, Randy.

Does anyone understand why the font_sun8x16 has any of those
'Depends on' ?

It's just a font structure definition.

Dave

> --
> ~Randy
--
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