From: Santosh Shilimkar Date: Thu, 1 Aug 2013 02:12:01 +0000 (+0100) Subject: ARM: 7805/1: mm: change max*pfn to include the physical offset of memory X-Git-Tag: firefly_0821_release~176^2~4991^2 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=26ba47b18318abe7dadbe9294a611c0e932651d8;p=firefly-linux-kernel-4.4.55.git ARM: 7805/1: mm: change max*pfn to include the physical offset of memory 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. Cc: Catalin Marinas Cc: Will Deacon Cc: Nicolas Pitre Signed-off-by: Santosh Shilimkar Signed-off-by: Russell King --- diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h index 5b579b951503..863cd84eb1a2 100644 --- a/arch/arm/include/asm/dma-mapping.h +++ b/arch/arm/include/asm/dma-mapping.h @@ -64,6 +64,7 @@ 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) { @@ -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 PHYS_PFN_OFFSET + 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 8aab24f35a5e..d50533c2b409 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -426,12 +426,10 @@ 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; } /* @@ -537,7 +535,7 @@ 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 */