kernel/arch/sh/mm/cache-sh2a.c

   1 /*
   2  * arch/sh/mm/cache-sh2a.c
   3  *
   4  * Copyright (C) 2008 Yoshinori Sato
   5  *
   6  * Released under the terms of the GNU GPL v2.0.
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/mm.h>
  11
  12 #include <asm/cache.h>
  13 #include <asm/addrspace.h>
  14 #include <asm/processor.h>
  15 #include <asm/cacheflush.h>
  16 #include <asm/io.h>
  17
  18 /*
  19  * The maximum number of pages we support up to when doing ranged dcache
  20  * flushing. Anything exceeding this will simply flush the dcache in its
  21  * entirety.
  22  */
  23 #define MAX_OCACHE_PAGES        32
  24 #define MAX_ICACHE_PAGES        32
  25
  26 #ifdef CONFIG_CACHE_WRITEBACK
  27 static void sh2a_flush_oc_line(unsigned long v, int way)
  28 {
  29         unsigned long addr = (v & 0x000007f0) | (way << 11);
  30         unsigned long data;
  31
  32         data = __raw_readl(CACHE_OC_ADDRESS_ARRAY | addr);
  33         if ((data & CACHE_PHYSADDR_MASK) == (v & CACHE_PHYSADDR_MASK)) {
  34                 data &= ~SH_CACHE_UPDATED;
  35                 __raw_writel(data, CACHE_OC_ADDRESS_ARRAY | addr);
  36         }
  37 }
  38 #endif
  39
  40 static void sh2a_invalidate_line(unsigned long cache_addr, unsigned long v)
  41 {
  42         /* Set associative bit to hit all ways */
  43         unsigned long addr = (v & 0x000007f0) | SH_CACHE_ASSOC;
  44         __raw_writel((addr & CACHE_PHYSADDR_MASK), cache_addr | addr);
  45 }
  46
  47 /*
  48  * Write back the dirty D-caches, but not invalidate them.
  49  */
  50 static void sh2a__flush_wback_region(void *start, int size)
  51 {
  52 #ifdef CONFIG_CACHE_WRITEBACK
  53         unsigned long v;
  54         unsigned long begin, end;
  55         unsigned long flags;
  56         int nr_ways;
  57
  58         begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
  59         end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
  60                 & ~(L1_CACHE_BYTES-1);
  61         nr_ways = current_cpu_data.dcache.ways;
  62
  63         local_irq_save(flags);
  64         jump_to_uncached();
  65
  66         /* If there are too many pages then flush the entire cache */
  67         if (((end - begin) >> PAGE_SHIFT) >= MAX_OCACHE_PAGES) {
  68                 begin = CACHE_OC_ADDRESS_ARRAY;
  69                 end = begin + (nr_ways * current_cpu_data.dcache.way_size);
  70
  71                 for (v = begin; v < end; v += L1_CACHE_BYTES) {
  72                         unsigned long data = __raw_readl(v);
  73                         if (data & SH_CACHE_UPDATED)
  74                                 __raw_writel(data & ~SH_CACHE_UPDATED, v);
  75                 }
  76         } else {
  77                 int way;
  78                 for (way = 0; way < nr_ways; way++) {
  79                         for (v = begin; v < end; v += L1_CACHE_BYTES)
  80                                 sh2a_flush_oc_line(v, way);
  81                 }
  82         }
  83
  84         back_to_cached();
  85         local_irq_restore(flags);
  86 #endif
  87 }
  88
  89 /*
  90  * Write back the dirty D-caches and invalidate them.
  91  */
  92 static void sh2a__flush_purge_region(void *start, int size)
  93 {
  94         unsigned long v;
  95         unsigned long begin, end;
  96         unsigned long flags;
  97
  98         begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
  99         end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
 100                 & ~(L1_CACHE_BYTES-1);
 101
 102         local_irq_save(flags);
 103         jump_to_uncached();
 104
 105         for (v = begin; v < end; v+=L1_CACHE_BYTES) {
 106 #ifdef CONFIG_CACHE_WRITEBACK
 107                 int way;
 108                 int nr_ways = current_cpu_data.dcache.ways;
 109                 for (way = 0; way < nr_ways; way++)
 110                         sh2a_flush_oc_line(v, way);
 111 #endif
 112                 sh2a_invalidate_line(CACHE_OC_ADDRESS_ARRAY, v);
 113         }
 114
 115         back_to_cached();
 116         local_irq_restore(flags);
 117 }
 118
 119 /*
 120  * Invalidate the D-caches, but no write back please
 121  */
 122 static void sh2a__flush_invalidate_region(void *start, int size)
 123 {
 124         unsigned long v;
 125         unsigned long begin, end;
 126         unsigned long flags;
 127
 128         begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
 129         end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
 130                 & ~(L1_CACHE_BYTES-1);
 131
 132         local_irq_save(flags);
 133         jump_to_uncached();
 134
 135         /* If there are too many pages then just blow the cache */
 136         if (((end - begin) >> PAGE_SHIFT) >= MAX_OCACHE_PAGES) {
 137                 __raw_writel(__raw_readl(SH_CCR) | CCR_OCACHE_INVALIDATE,
 138                              SH_CCR);
 139         } else {
 140                 for (v = begin; v < end; v += L1_CACHE_BYTES)
 141                         sh2a_invalidate_line(CACHE_OC_ADDRESS_ARRAY, v);
 142         }
 143
 144         back_to_cached();
 145         local_irq_restore(flags);
 146 }
 147
 148 /*
 149  * Write back the range of D-cache, and purge the I-cache.
 150  */
 151 static void sh2a_flush_icache_range(void *args)
 152 {
 153         struct flusher_data *data = args;
 154         unsigned long start, end;
 155         unsigned long v;
 156         unsigned long flags;
 157
 158         start = data->addr1 & ~(L1_CACHE_BYTES-1);
 159         end = (data->addr2 + L1_CACHE_BYTES-1) & ~(L1_CACHE_BYTES-1);
 160
 161 #ifdef CONFIG_CACHE_WRITEBACK
 162         sh2a__flush_wback_region((void *)start, end-start);
 163 #endif
 164
 165         local_irq_save(flags);
 166         jump_to_uncached();
 167
 168         /* I-Cache invalidate */
 169         /* If there are too many pages then just blow the cache */
 170         if (((end - start) >> PAGE_SHIFT) >= MAX_ICACHE_PAGES) {
 171                 __raw_writel(__raw_readl(SH_CCR) | CCR_ICACHE_INVALIDATE,
 172                              SH_CCR);
 173         } else {
 174                 for (v = start; v < end; v += L1_CACHE_BYTES)
 175                         sh2a_invalidate_line(CACHE_IC_ADDRESS_ARRAY, v);
 176         }
 177
 178         back_to_cached();
 179         local_irq_restore(flags);
 180 }
 181
 182 void __init sh2a_cache_init(void)
 183 {
 184         local_flush_icache_range        = sh2a_flush_icache_range;
 185
 186         __flush_wback_region            = sh2a__flush_wback_region;
 187         __flush_purge_region            = sh2a__flush_purge_region;
 188         __flush_invalidate_region       = sh2a__flush_invalidate_region;
 189 }