On Thu, Apr 24, 2014 at 10:30 AM, Santosh Shilimkar <[email protected]> wrote: > From: Grygorii Strashko <[email protected]> > > In most of cases DMA addresses can be performed using offset value of > Bus address space relatively to physical address space as following: > > PFN->DMA: > __pfn_to_phys(pfn + [-]dma_pfn_offset) > > DMA->PFN: > __phys_to_pfn(dma_addr) + [-]dma_pfn_offset > > Cc: Greg Kroah-Hartman <[email protected]> > Cc: Russell King <[email protected]> > Cc: Arnd Bergmann <[email protected]> > Cc: Olof Johansson <[email protected]> > Cc: Grant Likely <[email protected]> > Cc: Rob Herring <[email protected]> > Cc: Catalin Marinas <[email protected]> > Cc: Linus Walleij <[email protected]> > Signed-off-by: Grygorii Strashko <[email protected]> > Signed-off-by: Santosh Shilimkar <[email protected]>
Reviewed-by: Rob Herring <[email protected]> > --- > arch/arm/include/asm/dma-mapping.h | 21 +++++++++++++++++---- > 1 file changed, 17 insertions(+), 4 deletions(-) > > 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); > } > > 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; > } > > 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))); > } > > 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)))); > } > > #else > -- > 1.7.9.5 > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
