Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965530Ab3GLVta (ORCPT ); Fri, 12 Jul 2013 17:49:30 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:59153 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757641Ab3GLVtZ (ORCPT ); Fri, 12 Jul 2013 17:49:25 -0400 From: Santosh Shilimkar To: , CC: Santosh Shilimkar , Russell King , Catalin Marinas , Will Deacon , Nicolas Pitre Subject: [RFC/RFT PATCH 4/5] ARM: mm: change max*pfn to include the physical offset of memory Date: Fri, 12 Jul 2013 17:48:13 -0400 Message-ID: <1373665694-7580-5-git-send-email-santosh.shilimkar@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1373665694-7580-1-git-send-email-santosh.shilimkar@ti.com> References: <1373665694-7580-1-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 Content-Length: 4022 Lines: 115 Most of the kernel code assumes that max*pfn is maximum pfns because the physical start of memory is expected to be PFN0. Since this assumption is not true on ARM architectures, the meaning of max*pfn is number of memory pages. This is done to keep drivers happy which are making use of of these variable to calculate the dma bounce limit using dma_mask. Now since we have a architecture override possibility for DMAable maximum pfns, lets make meaning of max*pfns as maximum pnfs on ARM as well. In the patch, the dma_to_pfn/pfn_to_dma() pair is hacked to take care of the physical memory offset. It is done this way just to enable testing since its understood that it can come in way of single zImage. Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Nicolas Pitre Signed-off-by: Santosh Shilimkar --- arch/arm/include/asm/dma-mapping.h | 16 ++++++++++++---- arch/arm/mm/init.c | 10 ++++------ 2 files changed, 16 insertions(+), 10 deletions(-) diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h index 5b579b9..b2d5937 100644 --- a/arch/arm/include/asm/dma-mapping.h +++ b/arch/arm/include/asm/dma-mapping.h @@ -47,12 +47,12 @@ 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); + return (dma_addr_t)__pfn_to_bus(pfn + PHYS_PFN_OFFSET); } static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr) { - return __bus_to_pfn(addr); + return __bus_to_pfn(addr) - PHYS_PFN_OFFSET; } static inline void *dma_to_virt(struct device *dev, dma_addr_t addr) @@ -64,15 +64,16 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr) { return (dma_addr_t)__virt_to_bus((unsigned long)(addr)); } + #else static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn) { - return __arch_pfn_to_dma(dev, pfn); + return __arch_pfn_to_dma(dev, pfn + PHYS_PFN_OFFSET); } static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr) { - return __arch_dma_to_pfn(dev, addr); + return __arch_dma_to_pfn(dev, addr) - PHYS_PFN_OFFSET; } static inline void *dma_to_virt(struct device *dev, dma_addr_t addr) @@ -86,6 +87,13 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr) } #endif +/* The ARM override for dma_max_pfn() */ +static inline unsigned long dma_max_pfn(struct device *dev) +{ + return dma_to_pfn(dev, *dev->dma_mask); +} +#define dma_max_pfn(dev) dma_max_pfn(dev) + /* * DMA errors are defined by all-bits-set in the DMA address. */ diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 6833cbe..588a2c1 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -420,12 +420,10 @@ void __init bootmem_init(void) * This doesn't seem to be used by the Linux memory manager any * more, but is used by ll_rw_block. If we can get rid of it, we * also get rid of some of the stuff above as well. - * - * Note: max_low_pfn and max_pfn reflect the number of _pages_ in - * the system, not the maximum PFN. */ - max_low_pfn = max_low - PHYS_PFN_OFFSET; - max_pfn = max_high - PHYS_PFN_OFFSET; + min_low_pfn = min; + max_low_pfn = max_low; + max_pfn = max_high; } /* @@ -531,7 +529,7 @@ static inline void free_area_high(unsigned long pfn, unsigned long end) static void __init free_highpages(void) { #ifdef CONFIG_HIGHMEM - unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET; + unsigned long max_low = max_low_pfn; struct memblock_region *mem, *res; /* set highmem page free */ -- 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/