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Re: ldrb vs ldrh in gcc-3.4.4 (ARM)

Steven Scholz wrote:

Richard,

Thanks a million. Maybe you could explain the difference of arm920t and arm9tdmi as well, please? 



The arm9tdmi is the main 'core' of the CPU.  The arm920t is the core
plus the associated cache, mmu, and system registers.   Different models
all have substantially the same 'core' but may have different (or
missing) additional parts...


Thanks. So when I am using Freescale i.MX and Atmel AT91RM9200 which are both arm920t I rather use

    GCC_EXTRA_CONFIG="--with-float=soft --with-cpu=arm920t \
                          --enable-cxx-flags=-mcpu=arm920t"

instead of

    GCC_EXTRA_CONFIG="--with-float=soft --with-cpu=arm9tdmi \
                          --enable-cxx-flags=-mcpu=arm9tdmi"

when building the toolchain. Right?

ARGH! There's no "--with-cpu=arm920t" !

gcc/config/arm/arm.h only knows

#define TARGET_CPU_arm9         0x0080
#define TARGET_CPU_arm9tdmi     0x0080

So when arm9tdmi is only thre core without caches will "--with-cpu=arm9tdmi" use the caches in a sane way ?

--
Steven


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