arch/parisc/mm/ioremap.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * arch/parisc/mm/ioremap.c
   4  *
   5  * (C) Copyright 1995 1996 Linus Torvalds
   6  * (C) Copyright 2001-2019 Helge Deller <deller@gmx.de>
   7  * (C) Copyright 2005 Kyle McMartin <kyle@parisc-linux.org>
   8  */
   9
  10 #include <linux/vmalloc.h>
  11 #include <linux/errno.h>
  12 #include <linux/module.h>
  13 #include <linux/io.h>
  14 #include <linux/mm.h>
  15
  16 void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
  17                            unsigned long prot)
  18 {
  19 #ifdef CONFIG_EISA
  20         unsigned long end = phys_addr + size - 1;
  21         /* Support EISA addresses */
  22         if ((phys_addr >= 0x00080000 && end < 0x000fffff) ||
  23             (phys_addr >= 0x00500000 && end < 0x03bfffff))
  24                 phys_addr |= F_EXTEND(0xfc000000);
  25 #endif
  26
  27         /*
  28          * Don't allow anybody to remap normal RAM that we're using..
  29          */
  30         if (phys_addr < virt_to_phys(high_memory)) {
  31                 char *t_addr, *t_end;
  32                 struct page *page;
  33
  34                 t_addr = __va(phys_addr);
  35                 t_end = t_addr + (size - 1);
  36
  37                 for (page = virt_to_page(t_addr);
  38                      page <= virt_to_page(t_end); page++) {
  39                         if(!PageReserved(page))
  40                                 return NULL;
  41                 }
  42         }
  43
  44         return generic_ioremap_prot(phys_addr, size, __pgprot(prot));
  45 }
  46 EXPORT_SYMBOL(ioremap_prot);