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Subject: Re: [PATCH] riscv: kbuild: drop CONFIG_RISCV_ISA_C
To:     Christoph Hellwig <hch@infradead.org>,
        Charles Papon <charles.papon.90@gmail.com>
Cc:     Atish Patra <atish.patra@wdc.com>,
        linux-riscv <linux-riscv@lists.infradead.org>,
        Bin Meng <bmeng.cn@gmail.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Paul Walmsley <paul.walmsley@sifive.com>
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 <20190812150348.GH26897@infradead.org>
From:   Darius Rad <darius@bluespec.com>
Message-ID: <5a931461-c6a8-6d2d-4f73-103a10b26f0e@bluespec.com>
Date:   Mon, 12 Aug 2019 15:49:06 -0400
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On 8/12/19 11:03 AM, Christoph Hellwig wrote:
> On Thu, Aug 08, 2019 at 02:18:53PM +0200, Charles Papon wrote:
>> Please do not drop it.
>>
>> Compressed instruction extension has some specific overhead in small
>> RISC-V FPGA softcore, especialy in the ones which can't implement the
>> register file read in a asynchronous manner because of the FPGA
>> technology.
>> What are reasons to enforce RVC ?
> 
> Because it it the unix platform baseline as stated in the patch.
> 

The same argument could be made for an FPU or MMU, yet there are options 
to disable those.