arch/csky/mm/ioremap.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
   3
   4 #include <linux/export.h>
   5 #include <linux/mm.h>
   6 #include <linux/vmalloc.h>
   7 #include <linux/io.h>
   8
   9 #include <asm/pgtable.h>
  10
  11 void __iomem *ioremap(phys_addr_t addr, size_t size)
  12 {
  13         phys_addr_t last_addr;
  14         unsigned long offset, vaddr;
  15         struct vm_struct *area;
  16         pgprot_t prot;
  17
  18         last_addr = addr + size - 1;
  19         if (!size || last_addr < addr)
  20                 return NULL;
  21
  22         offset = addr & (~PAGE_MASK);
  23         addr &= PAGE_MASK;
  24         size = PAGE_ALIGN(size + offset);
  25
  26         area = get_vm_area_caller(size, VM_ALLOC, __builtin_return_address(0));
  27         if (!area)
  28                 return NULL;
  29
  30         vaddr = (unsigned long)area->addr;
  31
  32         prot = __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE |
  33                         _PAGE_GLOBAL | _CACHE_UNCACHED | _PAGE_SO);
  34
  35         if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
  36                 free_vm_area(area);
  37                 return NULL;
  38         }
  39
  40         return (void __iomem *)(vaddr + offset);
  41 }
  42 EXPORT_SYMBOL(ioremap);
  43
  44 void iounmap(void __iomem *addr)
  45 {
  46         vunmap((void *)((unsigned long)addr & PAGE_MASK));
  47 }
  48 EXPORT_SYMBOL(iounmap);
  49
  50 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
  51                               unsigned long size, pgprot_t vma_prot)
  52 {
  53         if (!pfn_valid(pfn)) {
  54                 vma_prot.pgprot |= _PAGE_SO;
  55                 return pgprot_noncached(vma_prot);
  56         } else if (file->f_flags & O_SYNC) {
  57                 return pgprot_noncached(vma_prot);
  58         }
  59
  60         return vma_prot;
  61 }
  62 EXPORT_SYMBOL(phys_mem_access_prot);