On Thu, Apr 24, 2014 at 11:30:05AM -0400, Santosh Shilimkar wrote: > diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h > index e701a4d..424fda9 100644 > --- a/arch/arm/include/asm/dma-mapping.h > +++ b/arch/arm/include/asm/dma-mapping.h > @@ -58,22 +58,35 @@ static inline int dma_set_mask(struct device *dev, u64 mask) > #ifndef __arch_pfn_to_dma > static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn) > { > - return (dma_addr_t)__pfn_to_bus(pfn); > + if (!dev) > + return (dma_addr_t)__pfn_to_bus(pfn); > + else > + return (dma_addr_t)__pfn_to_bus(pfn - dev->dma_pfn_offset); I really don't trust gcc to do this right, so I think it would be better to make life easier on the compiler: if (dev) pfn -= dev->dma_pfn_offset; return (dma_addr_t)__pfn_to_bus(pfn); > static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr) > { > - return __bus_to_pfn(addr); > + if (!dev) > + return __bus_to_pfn(addr); > + else > + return __bus_to_pfn(addr) + dev->dma_pfn_offset; and: unsigned long pfn = __bus_to_pfn(addr); if (dev) pfn += dev->dma_pfn_offset; return pfn; > } > > static inline void *dma_to_virt(struct device *dev, dma_addr_t addr) > { > - return (void *)__bus_to_virt((unsigned long)addr); > + if (!dev) > + return (void *)__bus_to_virt((unsigned long)addr); > + else > + return (void *)__bus_to_virt(__pfn_to_bus(dma_to_pfn(dev, addr))); This is quite horrendous. There's easier ways to do this... I assume you haven't looked at the assembler resulting from this at all with stuff like the p2v patching enabled? > } > > static inline dma_addr_t virt_to_dma(struct device *dev, void *addr) > { > - return (dma_addr_t)__virt_to_bus((unsigned long)(addr)); > + if (!dev) > + return (dma_addr_t)__virt_to_bus((unsigned long)(addr)); > + else > + return pfn_to_dma(dev, > + __bus_to_pfn(__virt_to_bus((unsigned long)(addr)))); Same here. -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html