arch/mips/mm/cache.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1994 - 2003 by Ralf Baechle
   7  */
   8 #include <linux/config.h>
   9 #include <linux/init.h>
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/sched.h>
  13 #include <linux/mm.h>
  14
  15 #include <asm/cacheflush.h>
  16 #include <asm/processor.h>
  17 #include <asm/cpu.h>
  18 #include <asm/cpu-features.h>
  19
  20 /* Cache operations. */
  21 void (*flush_cache_all)(void);
  22 void (*__flush_cache_all)(void);
  23 void (*flush_cache_mm)(struct mm_struct *mm);
  24 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
  25         unsigned long end);
  26 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
  27         unsigned long pfn);
  28 void (*flush_icache_range)(unsigned long start, unsigned long end);
  29 void (*flush_icache_page)(struct vm_area_struct *vma, struct page *page);
  30
  31 /* MIPS specific cache operations */
  32 void (*flush_cache_sigtramp)(unsigned long addr);
  33 void (*local_flush_data_cache_page)(void * addr);
  34 void (*flush_data_cache_page)(unsigned long addr);
  35 void (*flush_icache_all)(void);
  36
  37 EXPORT_SYMBOL(flush_data_cache_page);
  38
  39 #ifdef CONFIG_DMA_NONCOHERENT
  40
  41 /* DMA cache operations. */
  42 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
  43 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
  44 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
  45
  46 EXPORT_SYMBOL(_dma_cache_wback_inv);
  47 EXPORT_SYMBOL(_dma_cache_wback);
  48 EXPORT_SYMBOL(_dma_cache_inv);
  49
  50 #endif /* CONFIG_DMA_NONCOHERENT */
  51
  52 /*
  53  * We could optimize the case where the cache argument is not BCACHE but
  54  * that seems very atypical use ...
  55  */
  56 asmlinkage int sys_cacheflush(unsigned long addr,
  57         unsigned long bytes, unsigned int cache)
  58 {
  59         if (bytes == 0)
  60                 return 0;
  61         if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
  62                 return -EFAULT;
  63
  64         flush_icache_range(addr, addr + bytes);
  65
  66         return 0;
  67 }
  68
  69 void __flush_dcache_page(struct page *page)
  70 {
  71         struct address_space *mapping = page_mapping(page);
  72         unsigned long addr;
  73
  74         if (mapping && !mapping_mapped(mapping)) {
  75                 SetPageDcacheDirty(page);
  76                 return;
  77         }
  78
  79         /*
  80          * We could delay the flush for the !page_mapping case too.  But that
  81          * case is for exec env/arg pages and those are %99 certainly going to
  82          * get faulted into the tlb (and thus flushed) anyways.
  83          */
  84         addr = (unsigned long) page_address(page);
  85         flush_data_cache_page(addr);
  86 }
  87
  88 EXPORT_SYMBOL(__flush_dcache_page);
  89
  90 void __update_cache(struct vm_area_struct *vma, unsigned long address,
  91         pte_t pte)
  92 {
  93         struct page *page;
  94         unsigned long pfn, addr;
  95
  96         pfn = pte_pfn(pte);
  97         if (pfn_valid(pfn) && (page = pfn_to_page(pfn), page_mapping(page)) &&
  98             Page_dcache_dirty(page)) {
  99                 if (pages_do_alias((unsigned long)page_address(page),
 100                                    address & PAGE_MASK)) {
 101                         addr = (unsigned long) page_address(page);
 102                         flush_data_cache_page(addr);
 103                 }
 104
 105                 ClearPageDcacheDirty(page);
 106         }
 107 }
 108
 109 #define __weak __attribute__((weak))
 110
 111 static char cache_panic[] __initdata = "Yeee, unsupported cache architecture.";
 112
 113 void __init cpu_cache_init(void)
 114 {
 115         if (cpu_has_3k_cache) {
 116                 extern void __weak r3k_cache_init(void);
 117
 118                 r3k_cache_init();
 119                 return;
 120         }
 121         if (cpu_has_6k_cache) {
 122                 extern void __weak r6k_cache_init(void);
 123
 124                 r6k_cache_init();
 125                 return;
 126         }
 127         if (cpu_has_4k_cache) {
 128                 extern void __weak r4k_cache_init(void);
 129
 130                 r4k_cache_init();
 131                 return;
 132         }
 133         if (cpu_has_8k_cache) {
 134                 extern void __weak r8k_cache_init(void);
 135
 136                 r8k_cache_init();
 137                 return;
 138         }
 139         if (cpu_has_tx39_cache) {
 140                 extern void __weak tx39_cache_init(void);
 141
 142                 tx39_cache_init();
 143                 return;
 144         }
 145         if (cpu_has_sb1_cache) {
 146                 extern void __weak sb1_cache_init(void);
 147
 148                 sb1_cache_init();
 149                 return;
 150         }
 151
 152         panic(cache_panic);
 153 }