Is volatile always verboten for FSL QE structures?

Kumar Gala galak at
Sat Oct 3 02:41:28 EST 2009

On Oct 2, 2009, at 9:46 AM, Timur Tabi wrote:

> Michael Barkowski wrote:
>> Just wondering - is there a case where using volatile for UCC  
>> parameter RAM for example will not work, or is the use of I/O  
>> accessors everywhere an attempt to be portable to other  
>> architectures?
> 'volatile' just doesn't really do what you think it should do.  The  
> PowerPC architecture is too complicated w.r.t. ordering of reads and  
> writes.  In other words, you can't trust it.
> No one should be using 'volatile' to access I/O registers.

See Documentation/volatile-considered-harmful.txt

- k

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