Re: PCI Express support for 2.4 kernel

[Vladimir Kondratiev]

Arjan van de Ven wrote:

> > > +	/* dummy read to flush PCI write */
> > > +	readb(addr);
> > >      
> > This is going to choke some hardware, I guarantee.
> >
> > You always want to make sure your flush is of the same size at the 
> > write.  Reading a byte from an address that the hardware defines as 
> > "32-bit writes only" can get ugly real quick ;-)
> >    
>
> also reading back addr might not be the best choice in case some
> registers have side effects on reading, it's probably better to read
> back an address that is known to be ok to read (like the vendor ID
> field)
>
>  
Good idea!
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