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Date:   Tue, 25 Jul 2023 19:01:04 +0200
From:   Sam Ravnborg <sam@ravnborg.org>
To:     linux@treblig.org
Cc:     mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@csgroup.eu,
        benh@kernel.crashing.org, linuxppc-dev@lists.ozlabs.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] powerpc: Use shared font data
Message-ID: <20230725170104.GA838289@ravnborg.org>
References: <20230725000141.165985-1-linux@treblig.org>
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Hi David,

On Tue, Jul 25, 2023 at 01:01:41AM +0100, linux@treblig.org wrote:
> From: "Dr. David Alan Gilbert" <linux@treblig.org>
> 
> 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
> the same thing with the same data, and they also share a bunch
> of functions to manipulate the data.  I've previously posted a near
> identical patch for sparc.
> 
> One difference I notice in PowerPC is that there are a bunch of compile
> options for the .c files for the early code to avoid a bunch of security
> compilation features;  it's not clear to me if this is a problem for
> this font data.
> 
> Tested very lightly with a boot without FS in qemu.
> 
> Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>

Yep, looks very similar to sparc, so

Reviewed-by: Sam Ravnborg <sam@ravnborg.org>