From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jerry Van Baren <gerald.vanbaren@ge.com>
Date: Wed, 30 Apr 2008 11:51:48 -0400
Subject: [U-Boot-Users] cfi_flash.c and lost volatile qualifier
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References: <20080430153830.3CC7024681@gemini.denx.de>
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Wolfgang Denk wrote:
> In message <48188584.3060109@ge.com> you wrote:
>> The solution in the PowerPC world is to add a "eieio" or "sync" 
>> instruction[1] appropriately[2], which prevents the bus interface unit 
>> from reordering the memory operations.
> 
> No, the solution for ALL architectures  is  to  use  the  appropriate
> accessor  macros which take care of such things (and probably contain
> calls like sync or similar).
> 
> Best regards,
> 
> Wolfgang Denk

Agreed.

If my theory is correct, Adrian has turned up a problem with the ARM 
configuration that apparently only shows up for the PXA250.  Or I'm 
blowing smoke - nothing to see, move along.

The hairs on the back of my neck say it is a sync/bus interface unit 
problem.

I don't know if it is significant, not being very intimately familiar 
with ARM (and, in particular, the PXA250), but my quick grep turns up 
./include/asm-arm/io.h and a quick browsing shows no syncs.  The hairs 
on the back of my neck are starting to ache.  ;-)

static inline void sync(void)
{
}

#define __arch_getb(a)                  (*(volatile unsigned char *)(a))

gvb