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Message-ID: <b858ec2a84546d7cdb666fd01c44a23714a33332.camel@xry111.site>
Subject: Re: [PATCH] loongarch/crypto: Clean up useless assignment operations
From: Xi Ruoyao <xry111@xry111.site>
To: WANG Xuerui <kernel@xen0n.name>, =?gb2312?Q?=B9=D8=CE=C4=CC=CE?=
	 <guanwentao@uniontech.com>, =?gb2312?Q?=CD=F5=EA=C5=C1=A6?=
	 <wangyuli@uniontech.com>, herbert <herbert@gondor.apana.org.au>, davem
	 <davem@davemloft.net>, chenhuacai <chenhuacai@kernel.org>
Cc: linux-crypto <linux-crypto@vger.kernel.org>, loongarch
	 <loongarch@lists.linux.dev>, linux-kernel <linux-kernel@vger.kernel.org>
Date: Tue, 27 Feb 2024 17:22:18 +0800
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References: <20240226080328.334021-1-wangyuli@uniontech.com>
	 <48afa638-9145-40ee-9868-fa82a1fce271@xen0n.name>
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On Tue, 2024-02-27 at 15:42 +0800, WANG Xuerui wrote:
> Sorry. I have checked the manual and it turns out you & Yuli are=20
> correct: even though the narrower CRC instructions doesn't require=20
> GRLEN=3D64, they still *aren't* part of LA32 (LoongArch reference manual
> v1.10, Volume 1, Table 2-1). Counter-intuitive as it is, the original=20
> patch is correct nevertheless.

But I don't think the table in the spec will 100% reflect the real
status of the LA32 hardware.  And we should use CPUCFG to detect it
anyway.

Based on my experience programming some aeronautic device I'd say having
some hardware CRC support should be useful even in embedded area.

--=20
Xi Ruoyao <xry111@xry111.site>
School of Aerospace Science and Technology, Xidian University