• Kyle Moffett's avatar
    powerpc: Minimal private libgcc to build on Debian · 01baa056
    Kyle Moffett authored
    
    
    Standard Debian powerpc and powerpcspe systems only include hard-float
    libgcc in their native compilers, which causes scary build warnings when
    building U-Boot.
    
    Debian and other PowerPC-supporting distributions used to provide libgcc
    and other libraries in a "nof" (soft-float) form in the "multilib"
    packages.  As they were completely unused by the distribution and
    therefore tended to be very buggy it was decided to save some time on
    the part of the maintainers and build-servers by removing them.
    
    Admittedly, right now the linker warnings do not indicate any problems,
    as the included routines do not use any floating point at all.
    
    The concern is that if floating-point code were ever added it might
    cause hard-float code to be unexpectedly included in U-Boot without
    generating a hard error.  This would cause unexplained crashes or
    indeterminate results at runtime.
    
    The easiest way to resolve this is to borrow the routines that U-Boot
    needs from the Linux kernel, which has the same issue.
    
    Specifically, the routines are: _ashldi3(), _ashrdi3(), and _lshrdi3().
    They were borrowed from arch/powerpc/kernel/misc_32.S as of v2.6.38-rc5,
    commit 85e2efbb1db9a18d218006706d6e4fbeb0216213, and are GPLv2+.
    
    The Makefile framework was copied from the U-Boot ARM port.
    
    Signed-off-by: default avatarKyle Moffett <Kyle.D.Moffett@boeing.com>
    Cc: Wolfgang Denk <wd@denx.de>
    Cc: Kim Phillips <kim.phillips@freescale.com>
    Cc: Andy Fleming <afleming@gmail.com>
    Cc: Kumar Gala <kumar.gala@freescale.com>
    Cc: Stefan Roese <sr@denx.de>
    01baa056