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Date:   Fri, 30 Aug 2019 19:04:29 -0700 (PDT)
From:   Paul Walmsley <paul.walmsley@sifive.com>
To:     Charles Papon <charles.papon.90@gmail.com>
cc:     Christoph Hellwig <hch@infradead.org>,
        Bin Meng <bmeng.cn@gmail.com>,
        Atish Patra <atish.patra@wdc.com>,
        linux-riscv <linux-riscv@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] riscv: kbuild: drop CONFIG_RISCV_ISA_C
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Hi Charles,

On Tue, 13 Aug 2019, Charles Papon wrote:

> > Because it it the unix platform baseline as stated in the patch.
> I know that, but i'm looking for arguments why RVC could't be kept as
> an option, especialy it is only an optimisation option without
> behavioral/code changes.
> 
> That baseline make sense for heavy linux distributions, where you
> expect everybody to compile with a baseline set of ISA extentions, to
> make binary exchanges easier.
> But for smaller systems, i do not see advantages having RVC forced.

OK - I agree with you.

Still, I think it would be good if we made this option depend on other 
more general kernel configuration parameters for smaller systems.  Will 
think about this further.

Thanks for commenting on this, and am looking forward to adding a VexRiscv 
system to our kernel tests -


- Paul