mirror of https://gitee.com/openkylin/linux.git
61 lines
1.6 KiB
C
61 lines
1.6 KiB
C
/*
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* (c) Copyright 2006 Hewlett-Packard Development Company, L.P.
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* Bjorn Helgaas <bjorn.helgaas@hp.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/compiler.h>
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#include <linux/module.h>
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#include <linux/efi.h>
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#include <asm/io.h>
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#include <asm/meminit.h>
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static inline void __iomem *
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__ioremap (unsigned long offset, unsigned long size)
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{
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return (void __iomem *) (__IA64_UNCACHED_OFFSET | offset);
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}
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void __iomem *
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ioremap (unsigned long offset, unsigned long size)
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{
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u64 attr;
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unsigned long gran_base, gran_size;
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/*
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* For things in kern_memmap, we must use the same attribute
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* as the rest of the kernel. For more details, see
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* Documentation/ia64/aliasing.txt.
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*/
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attr = kern_mem_attribute(offset, size);
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if (attr & EFI_MEMORY_WB)
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return phys_to_virt(offset);
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else if (attr & EFI_MEMORY_UC)
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return __ioremap(offset, size);
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/*
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* Some chipsets don't support UC access to memory. If
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* WB is supported for the whole granule, we prefer that.
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*/
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gran_base = GRANULEROUNDDOWN(offset);
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gran_size = GRANULEROUNDUP(offset + size) - gran_base;
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if (efi_mem_attribute(gran_base, gran_size) & EFI_MEMORY_WB)
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return phys_to_virt(offset);
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return __ioremap(offset, size);
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}
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EXPORT_SYMBOL(ioremap);
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void __iomem *
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ioremap_nocache (unsigned long offset, unsigned long size)
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{
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if (kern_mem_attribute(offset, size) & EFI_MEMORY_WB)
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return 0;
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return __ioremap(offset, size);
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}
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EXPORT_SYMBOL(ioremap_nocache);
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