From mboxrd@z Thu Jan  1 00:00:00 1970
From: Amir Vadai <amirv@mellanox.com>
Subject: Re: [PATCH net] net/mlx4_en: correct the endianness of doorbell_qpn
 on big endian platform
Date: Mon, 15 Dec 2014 11:59:15 +0200
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 <20141208144237.GB8382@richard> <20141213031338.GA12208@richard>
 <20141213.234320.1607496855879763694.davem@davemloft.net>
 <20141215013249.GA7341@richard>
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Cc: "eric.dumazet@gmail.com" <eric.dumazet@gmail.com>,
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	Gideon Naim <gideonn@mellanox.com>,
	"edumazet@google.com" <edumazet@google.com>
To: Wei Yang <weiyang@linux.vnet.ibm.com>,
	David Miller <davem@davemloft.net>,
	"David.Laight@ACULAB.COM" <David.Laight@ACULAB.COM>
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On 12/15/2014 3:32 AM, Wei Yang wrote:
[...]

Hi David's,

I need to do a native endianness write to the NIC register (the write is
on the fast path and the register value could be calculated once).

iowrite32be() is calling cpu_to_be32() on the value.
iowrite32() is calling cpu_to_le32().

I thought about using raw_writel() but as David Miller said, it lacks
necessary io barriers on some archs.

Does the only solution to this, is to add some sort of
iowrite32be_native(__be32 val,...) function to all the archs?

Thanks,
Amir