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
  17 static 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
  50 void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size)
  51 {
  52         return xtensa_ioremap(addr, size, pgprot_noncached(PAGE_KERNEL));
  53 }
  54 EXPORT_SYMBOL(xtensa_ioremap_nocache);
  55
  56 void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size)
  57 {
  58         return xtensa_ioremap(addr, size, PAGE_KERNEL);
  59 }
  60 EXPORT_SYMBOL(xtensa_ioremap_cache);
  61
  62 void xtensa_iounmap(volatile void __iomem *io_addr)
  63 {
  64         void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
  65
  66         vunmap(addr);
  67 }
  68 EXPORT_SYMBOL(xtensa_iounmap);