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Subject: Re: [PATCH] drivers/block/xsysace - replace
 in(out)_8/in(out)_be16/in(out)_le16 with generic iowrite(read)8/16(be)
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Grant Likely <grant.likely@secretlab.ca>, Michal Simek <monstr@monstr.eu>,
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Date: Thu, 07 Feb 2013 23:23:13 +1100
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On Thu, 2013-02-07 at 23:20 +1100, Benjamin Herrenschmidt wrote:

> For the "swapped" case, I would suggest using ioread16be for the registers
> for the data port, use ioread16_rep followed by a pass of byteswap. I assume
> that this incorrect wiring case only happens on BE platforms right ?

Of course that won't work on writes unless you use a bounce buffer, but
heh, who cares, it's busted anyway ?

Another option is to stick with a loop of ioread16be/iowrite16be, it
*should* work, but it will have too many memory barriers, the impact
will vary depending on the core.

Cheers,
Ben.