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Date:   Wed, 08 Feb 2023 15:08:31 +0100
From:   "Arnd Bergmann" <arnd@arndb.de>
To:     "Huacai Chen" <chenhuacai@loongson.cn>,
        "Huacai Chen" <chenhuacai@kernel.org>
Cc:     loongarch@lists.linux.dev, Linux-Arch <linux-arch@vger.kernel.org>,
        "Xuefeng Li" <lixuefeng@loongson.cn>, guoren <guoren@kernel.org>,
        "WANG Xuerui" <kernel@xen0n.name>,
        "Jiaxun Yang" <jiaxun.yang@flygoat.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH V2] LoongArch: Make -mstrict-align configurable
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On Wed, Feb 8, 2023, at 15:05, Huacai Chen wrote:
> Introduce Kconfig option ARCH_STRICT_ALIGN to make -mstrict-align be
> configurable.
>
> Not all LoongArch cores support h/w unaligned access, we can use the
> -mstrict-align build parameter to prevent unaligned accesses.
>
> CPUs with h/w unaligned access support:
> Loongson-2K2000/2K3000/3A5000/3C5000/3D5000.
>
> CPUs without h/w unaligned access support:
> Loongson-2K500/2K1000.
>
> This option is enabled by default to make the kernel be able to run on
> all LoongArch systems. But you can disable it manually if you want to
> run kernel only on systems with h/w unaligned access support in order to
> optimise for performance.
>
> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Reviewed-by: Arnd Bergmann <arnd@arndb.de>