[U-Boot] [PATCH] arm: fix memory coherency problem after relocation

[Mike Dunn]

On 06/20/2013 06:56 AM, Marek Vasut wrote:
> Dear Mike Dunn,
> 
>> On the xscale, the icache must be invalidated and the write buffers drained
>> after writing code over the data bus, even if the caches are disabled. 
>> After rebasing with the main git repository, u-boot began crashing in odd
>> places on my pxa270 board (palmtreo680) after the code relocation routine
>> ran.  This patch fixes it.  Cache coherency problems are often
>> hit-and-miss (ha ha), and this latent problem didn't rear its ugly head
>> until now.  Tested on the pxa270.
>>
>> Signed-off-by: Mike Dunn <mikedunn at newsguy.com>
>> ---
>>
>> I realize that __ARM_ARCH_5TE__ does not necessarily mean xscale.
> 
> We should introduce some CONFIG_PXA I guess.


I think CONFIG_XSCALE is more correct, because if I'm not mistaken more recent
Marvell processors continue to use the 'pxa' nomenclature in their name but do
not contain xscale cores.

I'll take a stab at a patch if you like.  Maybe something like this macro in
arch/arm/include/asm/arch-pxa/hardware.h

/*
 * Define CONFIG_CPU_MONAHANS in case some CPU of the PXA3xx family is selected.
 * PXA300/310/320 all have distinct register mappings in some cases, that's why
 * the exact CPU has to be selected. CONFIG_CPU_MONAHANS is a helper for common
 * drivers and compatibility glue with old source then.
 */
#ifndef	CONFIG_CPU_MONAHANS
#if	defined(CONFIG_CPU_PXA300) || \
	defined(CONFIG_CPU_PXA310) || \
	defined(CONFIG_CPU_PXA320)
#define	CONFIG_CPU_MONAHANS
#endif
#endif

Thanks,
Mike