From: "Alex Bennée" <alex.bennee@linaro.org>
To: Richard Henderson <richard.henderson@linaro.org>
Cc: Peter Maydell <peter.maydell@linaro.org>,
Leandro Lupori <leandro.lupori@eldorado.org.br>,
danielhb413@gmail.com, qemu-devel@nongnu.org, groug@kaod.org,
qemu-ppc@nongnu.org, clg@kaod.org, pbonzini@redhat.com,
david@gibson.dropbear.id.au
Subject: Re: [RFC PATCH v3 2/5] ppc64: Fix semihosting on ppc64le
Date: Thu, 21 Apr 2022 09:46:30 +0100 [thread overview]
Message-ID: <87zgkevn3c.fsf@linaro.org> (raw)
In-Reply-To: <962f7ef4-7dcc-fb5d-5e55-90eb3ba65e47@linaro.org>
Richard Henderson <richard.henderson@linaro.org> writes:
> On 4/20/22 12:42, Peter Maydell wrote:
>> On Mon, 18 Apr 2022 at 20:19, Leandro Lupori
>> <leandro.lupori@eldorado.org.br> wrote:
>>>
>>> PPC64 CPUs can change its endian dynamically, so semihosting code
>>> must check its MSR at run time to determine if byte swapping is
>>> needed.
>> Arm CPUs also change endianness dynamically, so why is this
>> change PPC-specific ?
>
> I'm reasonably certain that we simply don't test armbe or aarch64_be
> semihosting. Leandro found this because qemu-system-ppc64 defaults to
> BE and qemu-system-aarch64 defaults to LE.
Maybe it is time to have a generic endianess variable in CPUState so we
can avoid having arch specific hacks in the semihosting code. That said
is endianess binary? I seem to recall on ARM the instruction stream is
always in one endianess so it only really affects CPU data loads and
stores. Is it the same for PPC?
>
>
> r~
--
Alex Bennée
next prev parent reply other threads:[~2022-04-21 9:04 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-18 19:10 [RFC PATCH v3 0/5] Port PPC64/PowerNV MMU tests to QEMU Leandro Lupori
2022-04-18 19:10 ` [RFC PATCH v3 1/5] ppc64: Add semihosting support Leandro Lupori
2022-04-18 20:22 ` Cédric Le Goater
2022-04-20 17:54 ` Leandro Lupori
2022-04-20 18:18 ` Richard Henderson
2022-04-20 18:38 ` Leandro Lupori
2022-04-20 18:09 ` Leandro Lupori
2022-04-21 2:04 ` Nicholas Piggin
2022-04-21 6:21 ` Cédric Le Goater
2022-04-21 9:56 ` Nicholas Piggin
2022-04-28 3:56 ` Nicholas Piggin
2022-05-03 15:50 ` Fabiano Rosas
2022-05-10 9:41 ` Nicholas Piggin
2022-04-21 6:12 ` Cédric Le Goater
2022-04-18 23:33 ` Richard Henderson
2022-04-19 9:26 ` Peter Maydell
2022-04-20 18:20 ` Leandro Lupori
2022-04-20 19:24 ` Peter Maydell
2022-04-20 18:05 ` Peter Maydell
2022-04-20 18:30 ` Leandro Lupori
2022-04-18 19:10 ` [RFC PATCH v3 2/5] ppc64: Fix semihosting on ppc64le Leandro Lupori
2022-04-18 23:36 ` Richard Henderson
2022-04-20 18:42 ` Leandro Lupori
2022-04-20 19:42 ` Peter Maydell
2022-04-20 19:52 ` Richard Henderson
2022-04-21 8:46 ` Alex Bennée [this message]
2022-04-21 9:13 ` Peter Maydell
2022-04-21 9:43 ` Alex Bennée
2022-04-21 10:01 ` Peter Maydell
2022-04-18 19:10 ` [RFC PATCH v3 3/5] tests/tcg/ppc64: Add basic softmmu test support Leandro Lupori
2022-04-18 20:27 ` Cédric Le Goater
2022-04-18 21:52 ` Daniel Henrique Barboza
2022-04-20 18:13 ` Leandro Lupori
2022-04-18 19:10 ` [RFC PATCH v3 4/5] tests/tcg/ppc64: Add MMU test sources Leandro Lupori
2022-04-18 19:11 ` [RFC PATCH v3 5/5] tests/tcg/ppc64: Build PowerNV and LE tests Leandro Lupori
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