[PATCH v2 1/1] sandbox: allow cross-compiling sandbox

[Sean Anderson]

On 2/10/21 1:20 PM, Sean Anderson wrote:
> 
> 
> On 2/10/21 12:54 PM, Heinrich Schuchardt wrote:
>  > UEFI test files like helloworld.efi require an architecture specific
>  > PE-COFF header.
>  >
>  > Currently this does not work for cross compiling. If $CROSS_COMPILE 
> is set,
>  > use the first part of the architecture triplet from the variable to
>  > choose the PE-COFF header.
>  >
>  > Now we can cross-compile the sandbox, e.g.
>  >
>  >      make sandbox_defconfig NO_SDL=1
>  >      CROSS_COMPILE=/opt/bin/aarch64-linux-gnu- NO_SDL=1 
> MK_ARCH=aarch64 make
>  >
>  > Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
>  > ---
>  > v2:
>  >     use $CROSS_COMPILE instead of an extra environment variable
>  > ---
>  >   Makefile | 10 +++++++---
>  >   1 file changed, 7 insertions(+), 3 deletions(-)
>  >
>  > diff --git a/Makefile b/Makefile
>  > index ebbedb1fb1..6c256a23b6 100644
>  > --- a/Makefile
>  > +++ b/Makefile
>  > @@ -17,9 +17,13 @@ NAME =
>  >   # o Look for make include files relative to root of kernel src
>  >   MAKEFLAGS += -rR --include-dir=$(CURDIR)
>  >
>  > -# Determine host architecture
>  > +# Determine target architecture for the sandbox
>  >   include include/host_arch.h
>  > -MK_ARCH="${shell uname -m}"
>  > +ifeq ("", "$(CROSS_COMPILE)")
>  > +  MK_ARCH="${shell uname -m}"
>  > +else
>  > +  MK_ARCH="${shell echo $(CROSS_COMPILE) | sed -n 
> 's/^\s*\([^\/]*\/\)*\([^-]*\)-\S*/\2/p'}"
>  > +endif
> 
> Won't this break cross-compiling? E.g. if on my x86_64 machine I run
> "CROSS_COMPILE=arm-linux-gnueabihf- make" my HOST_ARCH will be
> HOST_ARCH_ARM, even though it should be HOST_ARCH_X86_64.

And it seems I've confused HOSTARCH with HOST_ARCH...

(probably a good candidate for a rename)

--Sean

> 
> I think you need a separate variable for a "canadian cross." gcc uses
> "build," "host," and "target," but as-is U-Boot's HOST_ARCH is gcc's
> "build" arch.
> 
> --Sean
> 
>  >   unexport HOST_ARCH
>  >   ifeq ("x86_64", $(MK_ARCH))
>  >     export HOST_ARCH=$(HOST_ARCH_X86_64)
>  > @@ -27,7 +31,7 @@ else ifneq (,$(findstring $(MK_ARCH), "i386" "i486" 
> "i586" "i686"))
>  >     export HOST_ARCH=$(HOST_ARCH_X86)
>  >   else ifneq (,$(findstring $(MK_ARCH), "aarch64" "armv8l"))
>  >     export HOST_ARCH=$(HOST_ARCH_AARCH64)
>  > -else ifeq ("armv7l", $(MK_ARCH))
>  > +else ifneq (,$(findstring $(MK_ARCH), "arm" "armv7" "armv7l"))
>  >     export HOST_ARCH=$(HOST_ARCH_ARM)
>  >   else ifeq ("riscv32", $(MK_ARCH))
>  >     export HOST_ARCH=$(HOST_ARCH_RISCV32)
>  > --
>  > 2.30.0
>  >