LXR linux/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 */
  28extern void local_dcache_page_flush(struct page *page);
  29extern 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)
  42extern 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 */
  49static 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
  64static 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 */
  97