Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755071AbaDSOex (ORCPT ); Sat, 19 Apr 2014 10:34:53 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:58692 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754283AbaDSOe1 (ORCPT ); Sat, 19 Apr 2014 10:34:27 -0400 From: Santosh Shilimkar To: CC: , , Grygorii Strashko , Greg Kroah-Hartman , Russell King , Arnd Bergmann , Olof Johansson , Grant Likely , Rob Herring , Catalin Marinas , Linus Walleij , Santosh Shilimkar Subject: [PATCH v2 5/7] ARM: dma: Use dma_pfn_offset for dma address translation Date: Sat, 19 Apr 2014 10:32:50 -0400 Message-ID: <1397917972-6293-6-git-send-email-santosh.shilimkar@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1397917972-6293-1-git-send-email-santosh.shilimkar@ti.com> References: <1397917972-6293-1-git-send-email-santosh.shilimkar@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Grygorii Strashko 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 Cc: Russell King Cc: Arnd Bergmann Cc: Olof Johansson Cc: Grant Likely Cc: Rob Herring Cc: Catalin Marinas Cc: Linus Walleij Signed-off-by: Grygorii Strashko Signed-off-by: Santosh Shilimkar --- arch/arm/include/asm/dma-mapping.h | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h index e701a4d..8c12149 100644 --- a/arch/arm/include/asm/dma-mapping.h +++ b/arch/arm/include/asm/dma-mapping.h @@ -58,22 +58,31 @@ 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_ERROR_CODE; + 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 0; + 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 NULL; + 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_ERROR_CODE; + 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 linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/