[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [PATCH v3 for-1.1 0/9] target-arm: More inference rules

From: Peter Maydell
Subject: Re: [Qemu-devel] [PATCH v3 for-1.1 0/9] target-arm: More inference rules for features
Date: Tue, 6 Dec 2011 10:47:01 +0000

On 6 December 2011 00:30, Andreas Färber <address@hidden> wrote:
> Question: Should we also add the following rules?
> V7MP => V7

Well, V7MP indicates support for the Multiprocessing Extensions, which
are an optional extension to ARMv7-A and ARMv7-R. So in some sense
V7MP implies V7. However it's not like the "main series" v4-v5-v6-v7.
So I think I'd rather not have the rule there: then when you're defining
the CPU you're effectively defining the main architecture version (V7)
and also specifying any optional extensions (V7MP).


Again, this is kind of true by accident -- THUMB2EE is an extension
to V7AR, and V7AR mandates THUMB2, so any core with THUMB2EE has
THUMB2, but it's not the kind of dependency I'd want to put in a rule
for. (V7 and A profile (not R) does imply THUMB2EE, but we don't
currently have a feature flag to distinguish A and R profiles unless
you want to claim that FEATURE_MPU does that...)

-- PMM

reply via email to

[Prev in Thread] Current Thread [Next in Thread]