armv6 tree vs. buildkernel

[Warner Losh]

On Jun 22, 2012, at 10:11 PM, Tim Kientzle wrote:

> On the BeagleBone, running a very recent armv6 tree:
> 
> # make TARGET_CPUTYPE=armv6 buildworld
> # make TARGET_CPUTYPE=armv6 KERNCONF=BEAGLEBONE buildkernel
> ….
> --------------------------------------------------------------
>>>> stage 3.2: building everything
> --------------------------------------------------------------
> cd /usr/obj/usr/src/sys/BEAGLEBONE; MAKEOBJDIRPREFIX=/usr/obj  MACHINE_ARCH=arm  MACHINE=arm  CPUTYPE=armv6 GROFF_BIN_PATH=/usr/obj/usr/src/tmp/legacy/usr/bin  GROFF_FONT_PATH=/usr/obj/usr/src/tmp/legacy/usr/share/groff_font  GROFF_TMAC_PATH=/usr/obj/usr/src/tmp/legacy/usr/share/tmac  _SHLIBDIRPREFIX=/usr/obj/usr/src/tmp  VERSION="FreeBSD 10.0-CURRENT arm 1000011"  INSTALL="sh /usr/src/tools/install.sh"  PATH=/usr/obj/usr/src/tmp/legacy/usr/sbin:/usr/obj/usr/src/tmp/legacy/usr/bin:/usr/obj/usr/src/tmp/legacy/usr/games:/usr/obj/usr/src/tmp/usr/sbin:/usr/obj/usr/src/tmp/usr/bin:/usr/obj/usr/src/tmp/usr/games:/sbin:/bin:/usr/sbin:/usr/bin make KERNEL=kernel all -DNO_MODULES_OBJ
> cc -mlittle-endian -c -x assembler-with-cpp -DLOCORE -O -pipe -march=armv6 -DARM_ARCH_6=1 -std=c99 -g -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes  -Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual  -Wundef -Wno-pointer-sign -fformat-extensions  -Wmissing-include-dirs -fdiagnostics-show-option   -nostdinc  -I. -I/usr/src/sys -I/usr/src/sys/contrib/altq -I/usr/src/sys/contrib/libfdt -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h -fno-common -finline-limit=8000 --param inline-unit-growth=100 --param large-function-growth=1000 -D_ARM_ARCH_6 -ffreestanding -Werror /usr/src/sys/arm/arm/locore.S
> In file included from /usr/src/sys/arm/arm/locore.S:38:
> ./machine/asm.h:139:1: error: "_ARM_ARCH_6" redefined
> <command-line>: error: this is the location of the previous definition
> 
> 
> One solution to this seems to be to edit sys/arm/include/asm.h to properly redefine these symbols, e.g.,
> 
>  #if defined(_ARM_ARCH_7) || defined (__ARM_ARCH_6__) || \
>      defined (__ARM_ARCH_6J__)
> + #undef _ARM_ARCH_6
>  #define _ARM_ARCH_6
>  #endif
> 
> 
> After this change, it gets as far as:
> 
> cc -mlittle-endian -c -O -pipe -march=armv6 -DARM_ARCH_6=1 -std=c99 -g -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes  -Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual  -Wundef -Wno-pointer-sign -fformat-extensions  -Wmissing-include-dirs -fdiagnostics-show-option   -nostdinc  -I. -I/usr/src/sys -I/usr/src/sys/contrib/altq -I/usr/src/sys/contrib/libfdt -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h -fno-common -finline-limit=8000 --param inline-unit-growth=100 --param large-function-growth=1000 -D_ARM_ARCH_6 -ffreestanding -Werror  /usr/src/sys/kern/kern_clock.c
> {standard input}: Assembler messages:
> {standard input}:1363: Error: selected processor does not support `dmb'
> {standard input}:1382: Error: selected processor does not support `dmb'
> *** [kern_clock.o] Error code 1
> 
> This seems to be due to some mismatch between sys/arm/include/atomic.h (which is getting ARM_ARCH_7A from somewhere?) and the -march setting.  I hope to track down the details this weekend.
> 
> Tim
> 
> P.S.  How is CPUTYPE/TARGET_CPUTYPE supposed to be inferred for regular "buildworld"?
> The only option I can find is to set it explicitly in /etc/src.conf

It can't possibly work very well.  We need to get TARGET_ARCH=armv6 working instead of continuing these kludges.

Warner