Re: [PATCH] lib/fonts: Avoid unncessary 64-bit math in font code

[Helge Deller <deller@kernel.org>]

* Ethan Nelson-Moore <enelsonmoore@gmail.com>:
> Hi, Helge and Thomas,
> 
> On Mon, Jun 8, 2026 at 12:58 PM Helge Deller <deller@gmx.de> wrote:
> >
> > On 6/8/26 13:25, Thomas Zimmermann wrote:
> > > Why is there a 64-bit division at all?
> >
> > Not sure. Might be platform specific.
> > Maybe, because you add two integers and divide by an integer, that the
> > compiler then chooses to use 64-bit integer division by 32-bit integer.
> 
> Actually, I think the real issue is that
> arch/arm/boot/compressed/Makefile defines "static" to nothing when
> compiling its copy of lib/fonts/font_acorn_8x8.c (via font.c), so that
> the font array is available outside of the object file. I assume that
> this causes various unused static inline functions in the headers it
> includes (such as <linux/math.h>) to be included in the object file
> because they become normal inline functions.

Does this patch fix the issue then?

diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index a159120d1e42..e3f550d62857 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -157,4 +157,4 @@ $(obj)/piggy_data: $(obj)/../Image FORCE
 
 $(obj)/piggy.o: $(obj)/piggy_data
 
-CFLAGS_font.o := -Dstatic=
+CFLAGS_font.o := -DBOOTLOADER
diff --git a/lib/fonts/font_acorn_8x8.c b/lib/fonts/font_acorn_8x8.c
index 36c51016769d..3327aa6d161d 100644
--- a/lib/fonts/font_acorn_8x8.c
+++ b/lib/fonts/font_acorn_8x8.c
@@ -5,7 +5,11 @@
 
 #define FONTDATAMAX 2048
 
+#ifndef BOOTLOADER
 static const struct font_data acorndata_8x8 = {
+#else
+const struct font_data acorndata_8x8 = {
+#endif
 { 0, 0, FONTDATAMAX, 0 }, {
 /* 00 */  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ^@ */
 /* 01 */  0x7e, 0x81, 0xa5, 0x81, 0xbd, 0x99, 0x81, 0x7e, /* ^A */