arch/nds32/include/asm/highmem.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 // Copyright (C) 2005-2017 Andes Technology Corporation
   3
   4 #ifndef _ASM_HIGHMEM_H
   5 #define _ASM_HIGHMEM_H
   6
   7 #include <asm/proc-fns.h>
   8 #include <asm/fixmap.h>
   9
  10 /*
  11  * Right now we initialize only a single pte table. It can be extended
  12  * easily, subsequent pte tables have to be allocated in one physical
  13  * chunk of RAM.
  14  */
  15 /*
  16  * Ordering is (from lower to higher memory addresses):
  17  *
  18  * high_memory
  19  *                      Persistent kmap area
  20  * PKMAP_BASE
  21  *                      fixed_addresses
  22  * FIXADDR_START
  23  * FIXADDR_TOP
  24  *                      Vmalloc area
  25  * VMALLOC_START
  26  * VMALLOC_END
  27  */
  28 #define PKMAP_BASE              ((FIXADDR_START - PGDIR_SIZE) & (PGDIR_MASK))
  29 #define LAST_PKMAP              PTRS_PER_PTE
  30 #define LAST_PKMAP_MASK         (LAST_PKMAP - 1)
  31 #define PKMAP_NR(virt)          (((virt) - (PKMAP_BASE)) >> PAGE_SHIFT)
  32 #define PKMAP_ADDR(nr)          (PKMAP_BASE + ((nr) << PAGE_SHIFT))
  33
  34 static inline void flush_cache_kmaps(void)
  35 {
  36         cpu_dcache_wbinval_all();
  37 }
  38
  39 /* declarations for highmem.c */
  40 extern unsigned long highstart_pfn, highend_pfn;
  41
  42 extern pte_t *pkmap_page_table;
  43
  44 extern void kmap_init(void);
  45
  46 /*
  47  * FIXME: The below looks broken vs. a kmap_atomic() in task context which
  48  * is interupted and another kmap_atomic() happens in interrupt context.
  49  * But what do I know about nds32. -- tglx
  50  */
  51 #define arch_kmap_local_post_map(vaddr, pteval)                 \
  52         do {                                                    \
  53                 __nds32__tlbop_inv(vaddr);                      \
  54                 __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);     \
  55                 __nds32__tlbop_rwr(pteval);                     \
  56                 __nds32__isb();                                 \
  57         } while (0)
  58
  59 #define arch_kmap_local_pre_unmap(vaddr)                        \
  60         do {                                                    \
  61                 __nds32__tlbop_inv(vaddr);                      \
  62                 __nds32__isb();                                 \
  63         } while (0)
  64
  65 #endif