Bug#836741: linux: FTBFS on powerpcspe due to the use of unsupported instructions

[John Paul Adrian Glaubitz]

Source: linux
Version: 4.7.2-1
Severity: normal
User: debian-powerpc at lists.debian.org
Usertags: powerpcspe

Hi!

Linux 4.7.x introduced another regression on powerpcspe due to the use of
unsupported assembly instructions [1]:

/<<PKGBUILDDIR>>/arch/powerpc/xmon/spr_access.S: Assembler messages:
/<<PKGBUILDDIR>>/arch/powerpc/xmon/spr_access.S:5: Error: unrecognized opcode: `ld'
/<<PKGBUILDDIR>>/arch/powerpc/xmon/spr_access.S:10: Error: unrecognized opcode: `ld'
/<<PKGBUILDDIR>>/scripts/Makefile.build:331: recipe for target 'arch/powerpc/xmon/spr_access.o' failed
make[6]: *** [arch/powerpc/xmon/spr_access.o] Error 1

This is very reminiscent of #823526 [2] which also used some FPU instructions
not available on powerpcspe/e500. And, indeed, like "ldarx" and "stdcx", "ld"
is not available on e500 either [3] (see p. 3-68).

I haven't looked at the code yet, but I assume guarding the code with some
additional #ifdef's should fix the issue the same way as in #823526.

Thanks,
Adrian

> [1] https://buildd.debian.org/status/fetch.php?pkg=linux&arch=powerpcspe&ver=4.7.2-1&stamp=1472977882
> [2] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=823526
> [3] http://www.nxp.com/files/32bit/doc/ref_manual/E500CORERM.pdf

--
 .''`.  John Paul Adrian Glaubitz
 : :' :  Debian Developer - glaubitz at debian.org
 `. `'   Freie Universitaet Berlin - glaubitz at physik.fu-berlin.de
   `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913