arch/xtensa/mm/ioremap.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * ioremap implementation.
   4  *
   5  * Copyright (C) 2015 Cadence Design Systems Inc.
   6  */
   7
   8 #include <linux/io.h>
   9 #include <linux/vmalloc.h>
  10 #include <linux/pgtable.h>
  11 #include <asm/cacheflush.h>
  12 #include <asm/io.h>
  13
  14 static void __iomem *xtensa_ioremap(unsigned long paddr, unsigned long size,
  15                                     pgprot_t prot)
  16 {
  17         unsigned long offset = paddr & ~PAGE_MASK;
  18         unsigned long pfn = __phys_to_pfn(paddr);
  19         struct vm_struct *area;
  20         unsigned long vaddr;
  21         int err;
  22
  23         paddr &= PAGE_MASK;
  24
  25         WARN_ON(pfn_valid(pfn));
  26
  27         size = PAGE_ALIGN(offset + size);
  28
  29         area = get_vm_area(size, VM_IOREMAP);
  30         if (!area)
  31                 return NULL;
  32
  33         vaddr = (unsigned long)area->addr;
  34         area->phys_addr = paddr;
  35
  36         err = ioremap_page_range(vaddr, vaddr + size, paddr, prot);
  37
  38         if (err) {
  39                 vunmap((void *)vaddr);
  40                 return NULL;
  41         }
  42
  43         flush_cache_vmap(vaddr, vaddr + size);
  44         return (void __iomem *)(offset + vaddr);
  45 }
  46
  47 void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size)
  48 {
  49         return xtensa_ioremap(addr, size, pgprot_noncached(PAGE_KERNEL));
  50 }
  51 EXPORT_SYMBOL(xtensa_ioremap_nocache);
  52
  53 void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size)
  54 {
  55         return xtensa_ioremap(addr, size, PAGE_KERNEL);
  56 }
  57 EXPORT_SYMBOL(xtensa_ioremap_cache);
  58
  59 void xtensa_iounmap(volatile void __iomem *io_addr)
  60 {
  61         void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
  62
  63         vunmap(addr);
  64 }
  65 EXPORT_SYMBOL(xtensa_iounmap);