[PATCH 6/7] ARM: use the common dma_to_phys/phys_to_dma implementation where possible

Christoph Hellwig hch at lst.de
Thu Apr 21 07:12:29 PDT 2022


On Thu, Apr 21, 2022 at 10:05:11AM +0200, Arnd Bergmann wrote:
> > -unsigned long __pfn_to_bus(unsigned long pfn)
> > +#else
> > +static inline unsigned long fb_bus_sdram_offset(void)
> >  {
> > -       return __pfn_to_phys(pfn) + (fb_bus_sdram_offset() - PHYS_OFFSET);
> > +       return BUS_OFFSET;
> >  }
> > -EXPORT_SYMBOL(__pfn_to_bus);
> > +#endif /* CONFIG_FOOTBRIDGE_ADDIN */
> 
> I have an older patch to remove CONFIG_FOOTBRIDGE_ADDIN
> completely, as it does a couple of other nasty things and there are
> apparently no users. Would that help here?

For this series it doesn't really make much of a difference.  The addin
case actually is simpler than the host mode for DMA,  But overall
CONFIG_FOOTBRIDGE_ADDIN seems to be a collection of special cases, so
if it is unused and can be remove that would probably be a good thing.



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