From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ron Mercer <ron.mercer@qlogic.com>
Subject: Re: [PATCH 3/5] qlge: bugfix: Fix endian issue regarding shadow registers.
Date: Wed, 24 Dec 2008 13:29:03 -0800
Message-ID: <20081224212903.GA16018@susedev.qlogic.org>
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Cc: Ben Hutchings <bhutchings@solarflare.com>,
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To: Christoph Hellwig <hch@infradead.org>
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On Wed, Dec 24, 2008 at 01:15:21PM -0800, Christoph Hellwig wrote:
> > I think that should be:
> > 	???return le32_to_cpu(*(const volatile __le32 *)addr);
> 
> No.  It needs more love than that.
> 
> ql_read_sh_reg is only used to access .prod_idx_sh_reg in the rx_ring
> structure, which is an offset from the .rx_ring_shadow_reg_area member.
> So instead of all this werid casting .prod_idx_sh_reg should simply
> be a __le32 pointer, whithout volatile and the other mess, and then
> you can use le32_to_cpu directly and kill the helper.

Yes, .prod_idx_sh_reg should be an __le32 *, but the volatile modifier 
was used since the memory location is modified by the chip and read by 
the driver.  Isn't that a case where it should be used?

> 
> And please verify the whole driver for endianess issues using sparse
> while you're at it...

Will do...