Hello Paul, thank you for answer. Yes i saw video-*.c files, but i can't understand how compilation of these video-*.c files depends on _WAKEUP macro... For example if'd remove -D_WAKEUP, i get errors during realmode.elf linking: arch/x86/realmode/rm/video-vga.o: In function `vga_probe': /home/alex/dev/linux/arch/x86/realmode/rm/../../boot/video-vga.c:259: undefined reference to `boot_params' As you wrote there are many #ifndef/#endif directives, but why there _WAKEUP is undefined everytime, but we pass it from command line with -D_WAKEUP? Thank you. 2015-01-07 22:54 GMT+06:00 Paul Bolle <pebolle@xxxxxxxxxx>: > On Wed, 2015-01-07 at 20:12 +0600, Alexander Kuleshov wrote: >> There is following definition at arch/x86/realmode/rm/Makefile: >> >> KBUILD_CFLAGS := $(LINUXINCLUDE) $(REALMODE_CFLAGS) -D_SETUP -D_WAKEUP \ >> -I$(srctree)/arch/x86/boot >> >> Is it used now? I'm asking because _WAKEUP definition everywhere >> undefined in the code. > > git grep tells me: > $ git grep -n "_WAKEUP\b" arch/x86 > arch/x86/boot/video-bios.c:51:#ifndef _WAKEUP > arch/x86/boot/video-bios.c:66:#ifdef _WAKEUP > arch/x86/boot/video-mode.c:169:#ifndef _WAKEUP > arch/x86/boot/video-vesa.c:27:#ifndef _WAKEUP > arch/x86/boot/video-vesa.c:29:#else /* _WAKEUP */ > arch/x86/boot/video-vesa.c:31:#endif /* _WAKEUP */ > arch/x86/boot/video-vesa.c:160:#ifndef _WAKEUP > arch/x86/boot/video-vesa.c:272:#endif /* not _WAKEUP */ > arch/x86/boot/video-vga.c:257:#ifndef _WAKEUP > arch/x86/boot/video-vga.c:269:#ifndef _WAKEUP > > And in that Makefile we also see, a few lines up: > wakeup-objs := [...] video-mode.o > [...] > wakeup-objs += video-vga.o > wakeup-objs += video-vesa.o > wakeup-objs += video-bios.o > > So this Makefile line defines a _WAKEUP macro that is, it seems, used > for the build of those four object files. (It's bit more complicated > than that. But I think KBUILD_CFLAGS is explained in Documentation/, > isn't it?) > > Hope this helps, > > > Paul Bolle > -- _________________________ 0xAX _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
