RE: [ECOS] Vr4131 porting issues

["Jurica Baricevic" <jura at INTESIS dot hr>]

Bart Veer wrote:
>     Jura> Sounds great. Bart seems much more reserved with this issue
>     Jura> though. He made me think that the mips64vr4100-elf would be
>     Jura> the only safe path to go.
>
> I am not sure I meant to imply that.
>
> The problem is that the mipsisa32-elf toolchain may never have been
> tested on the NEC VR4xxx series, or on a TX49. Ideally you would not
> use a toolchain for a given processor unless it has been tested,
> possibly just a full run of eCos tests, preferably a full run of the
> gcc testsuite as well. The toolchain should work, but unpleasant
> surprises are possible.
>
> On the other hand it is also possible that nobody has built, let alone
> tested, a mips64vr4xxx-elf toolchain using gcc 3.2.1 sources. If so
> then there would be no reason to prefer a mips64vr4xxx toolchain
> to a mipsisa32 toolchain. Either toolchain could be broken in various
> subtle or unsubtle ways. There may be information in the gcc mailing
> lists or on their web site about which targets have been tested.
>

Thank you on your explanation.

According to both your and gcc-list information gcc 3.2.1 should be avoided
for mips64vr4xxx targets (gcc 3.3 should give more support though).
Nevertheless, I have some issues with mipsisa32 too. Namely, I don't know if
anybody tried provided mipsisa32 toolchain with Vr4300, but
mipsisa32-elf-gdb used with Vr4100 is not able to understand messages from
GDB stubs (in Redboot). I guess it is due to the fact that mipsisa32-elf-gdb
does not support 64-bit registers. When I build the Redboot telling to stubs
that my registers are smaller (32-bits as Nick suggested) then a conflict
occurs between stubs and assembler code which saves 64-bit register context.

Also, I wasn't able to build mips64vr4300 target following your instructions
at the http://sources.redhat.com/ecos/build-toolchain.html. GCC 3.2.1
provided there doesn't support that target.

So, it seems that GCC 2.95.x is the way to go. However, the mips64vr4300-elf
target seems as not supported in that version too (I tried the to build the
sources provided on CD from Massa's book).
Seems like these are not the luckiest days of my life :-(


Best regards,
Jura



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