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Date:   Mon, 9 Jan 2023 12:40:54 +0200
From:   Vladimir Oltean <vladimir.oltean@nxp.com>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Sparse warning when using ioread64() from include/asm-generic/io.h
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Hi,

I would like to get rid of the following sparse error in the enetc
driver (for arm64), which uses ioread64().

../drivers/net/ethernet/freescale/enetc/enetc_ethtool.c: note: in included file
	(through ../arch/arm64/include/asm/io.h, ../include/linux/io.h,
	../include/linux/irq.h, ../include/asm-generic/hardirq.h,
	../arch/arm64/include/asm/hardirq.h, ...):
../include/asm-generic/io.h:239:15: warning: cast to restricted __le64

The trouble is I don't understand why the casts to __le64 and use of
__le64_to_cpu() are even needed, when everything seems to be native
endianness. I've seen commit c1d55d50139b ("asm-generic/io.h: Fix sparse
warnings on big-endian architectures"), but that doesn't claim to fix
anything for little endian (and doesn't touch the 64 accessors, for some
reason).

Could you please help?

Thanks,
Vladimir