arch/nds32/mm/highmem.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2005-2017 Andes Technology Corporation
   3
   4 #include <linux/export.h>
   5 #include <linux/highmem.h>
   6 #include <linux/sched.h>
   7 #include <linux/smp.h>
   8 #include <linux/interrupt.h>
   9 #include <linux/memblock.h>
  10 #include <asm/fixmap.h>
  11 #include <asm/tlbflush.h>
  12
  13 void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
  14 {
  15         unsigned int idx;
  16         unsigned long vaddr, pte;
  17         int type;
  18         pte_t *ptep;
  19
  20         type = kmap_atomic_idx_push();
  21
  22         idx = type + KM_TYPE_NR * smp_processor_id();
  23         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
  24         pte = (page_to_pfn(page) << PAGE_SHIFT) | prot;
  25         ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
  26         set_pte(ptep, pte);
  27
  28         __nds32__tlbop_inv(vaddr);
  29         __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);
  30         __nds32__tlbop_rwr(pte);
  31         __nds32__isb();
  32         return (void *)vaddr;
  33 }
  34 EXPORT_SYMBOL(kmap_atomic_high_prot);
  35
  36 void kunmap_atomic_high(void *kvaddr)
  37 {
  38         if (kvaddr >= (void *)FIXADDR_START) {
  39                 unsigned long vaddr = (unsigned long)kvaddr;
  40                 pte_t *ptep;
  41                 kmap_atomic_idx_pop();
  42                 __nds32__tlbop_inv(vaddr);
  43                 __nds32__isb();
  44                 ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
  45                 set_pte(ptep, 0);
  46         }
  47 }
  48 EXPORT_SYMBOL(kunmap_atomic_high);