LXR linux/arch/xtensa/mm/ioremap.c

   1/*
   2 * ioremap implementation.
   3 *
   4 * Copyright (C) 2015 Cadence Design Systems Inc.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 */
  10
  11#include <linux/io.h>
  12#include <linux/vmalloc.h>
  13#include <asm/cacheflush.h>
  14#include <asm/io.h>
  15#include <asm/pgtable.h>
  16
  17static void __iomem *xtensa_ioremap(unsigned long paddr, unsigned long size,
  18                                    pgprot_t prot)
  19{
  20        unsigned long offset = paddr & ~PAGE_MASK;
  21        unsigned long pfn = __phys_to_pfn(paddr);
  22        struct vm_struct *area;
  23        unsigned long vaddr;
  24        int err;
  25
  26        paddr &= PAGE_MASK;
  27
  28        WARN_ON(pfn_valid(pfn));
  29
  30        size = PAGE_ALIGN(offset + size);
  31
  32        area = get_vm_area(size, VM_IOREMAP);
  33        if (!area)
  34                return NULL;
  35
  36        vaddr = (unsigned long)area->addr;
  37        area->phys_addr = paddr;
  38
  39        err = ioremap_page_range(vaddr, vaddr + size, paddr, prot);
  40
  41        if (err) {
  42                vunmap((void *)vaddr);
  43                return NULL;
  44        }
  45
  46        flush_cache_vmap(vaddr, vaddr + size);
  47        return (void __iomem *)(offset + vaddr);
  48}
  49
  50void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size)
  51{
  52        return xtensa_ioremap(addr, size, pgprot_noncached(PAGE_KERNEL));
  53}
  54EXPORT_SYMBOL(xtensa_ioremap_nocache);
  55
  56void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size)
  57{
  58        return xtensa_ioremap(addr, size, PAGE_KERNEL);
  59}
  60EXPORT_SYMBOL(xtensa_ioremap_cache);
  61
  62void xtensa_iounmap(volatile void __iomem *io_addr)
  63{
  64        void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
  65
  66        vunmap(addr);
  67}
  68EXPORT_SYMBOL(xtensa_iounmap);
  69