arch/openrisc/include/asm/cacheflush.h

   1 /*
   2  * OpenRISC Linux
   3  *
   4  * Linux architectural port borrowing liberally from similar works of
   5  * others.  All original copyrights apply as per the original source
   6  * declaration.
   7  *
   8  * OpenRISC implementation:
   9  * Copyright (C) Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
  10  * et al.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  */
  17
  18 #ifndef __ASM_CACHEFLUSH_H
  19 #define __ASM_CACHEFLUSH_H
  20
  21 #include <linux/mm.h>
  22
  23 /*
  24  * Helper function for flushing or invalidating entire pages from data
  25  * and instruction caches. SMP needs a little extra work, since we need
  26  * to flush the pages on all cpus.
  27  */
  28 extern void local_dcache_page_flush(struct page *page);
  29 extern void local_icache_page_inv(struct page *page);
  30
  31 /*
  32  * Data cache flushing always happen on the local cpu. Instruction cache
  33  * invalidations need to be broadcasted to all other cpu in the system in
  34  * case of SMP configurations.
  35  */
  36 #ifndef CONFIG_SMP
  37 #define dcache_page_flush(page)      local_dcache_page_flush(page)
  38 #define icache_page_inv(page)        local_icache_page_inv(page)
  39 #else  /* CONFIG_SMP */
  40 #define dcache_page_flush(page)      local_dcache_page_flush(page)
  41 #define icache_page_inv(page)        smp_icache_page_inv(page)
  42 extern void smp_icache_page_inv(struct page *page);
  43 #endif /* CONFIG_SMP */
  44
  45 /*
  46  * Synchronizes caches. Whenever a cpu writes executable code to memory, this
  47  * should be called to make sure the processor sees the newly written code.
  48  */
  49 static inline void sync_icache_dcache(struct page *page)
  50 {
  51         if (!IS_ENABLED(CONFIG_DCACHE_WRITETHROUGH))
  52                 dcache_page_flush(page);
  53         icache_page_inv(page);
  54 }
  55
  56 /*
  57  * Pages with this bit set need not be flushed/invalidated, since
  58  * they have not changed since last flush. New pages start with
  59  * PG_arch_1 not set and are therefore dirty by default.
  60  */
  61 #define PG_dc_clean                  PG_arch_1
  62
  63 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
  64 static inline void flush_dcache_page(struct page *page)
  65 {
  66         clear_bit(PG_dc_clean, &page->flags);
  67 }
  68
  69 /*
  70  * Other interfaces are not required since we do not have virtually
  71  * indexed or tagged caches. So we can use the default here.
  72  */
  73 #define flush_cache_all()                               do { } while (0)
  74 #define flush_cache_mm(mm)                              do { } while (0)
  75 #define flush_cache_dup_mm(mm)                          do { } while (0)
  76 #define flush_cache_range(vma, start, end)              do { } while (0)
  77 #define flush_cache_page(vma, vmaddr, pfn)              do { } while (0)
  78 #define flush_dcache_mmap_lock(mapping)                 do { } while (0)
  79 #define flush_dcache_mmap_unlock(mapping)               do { } while (0)
  80 #define flush_icache_range(start, end)                  do { } while (0)
  81 #define flush_icache_page(vma, pg)                      do { } while (0)
  82 #define flush_icache_user_range(vma, pg, adr, len)      do { } while (0)
  83 #define flush_cache_vmap(start, end)                    do { } while (0)
  84 #define flush_cache_vunmap(start, end)                  do { } while (0)
  85
  86 #define copy_to_user_page(vma, page, vaddr, dst, src, len)           \
  87         do {                                                         \
  88                 memcpy(dst, src, len);                               \
  89                 if (vma->vm_flags & VM_EXEC)                         \
  90                         sync_icache_dcache(page);                    \
  91         } while (0)
  92
  93 #define copy_from_user_page(vma, page, vaddr, dst, src, len)         \
  94         memcpy(dst, src, len)
  95
  96 #endif /* __ASM_CACHEFLUSH_H */