arch/sh/mm/cache-debugfs.c

   1 /*
   2  * debugfs ops for the L1 cache
   3  *
   4  *  Copyright (C) 2006  Paul Mundt
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file "COPYING" in the main directory of this archive
   8  * for more details.
   9  */
  10 #include <linux/init.h>
  11 #include <linux/module.h>
  12 #include <linux/debugfs.h>
  13 #include <linux/seq_file.h>
  14 #include <asm/processor.h>
  15 #include <asm/uaccess.h>
  16 #include <asm/cache.h>
  17 #include <asm/io.h>
  18
  19 enum cache_type {
  20         CACHE_TYPE_ICACHE,
  21         CACHE_TYPE_DCACHE,
  22         CACHE_TYPE_UNIFIED,
  23 };
  24
  25 static int __uses_jump_to_uncached cache_seq_show(struct seq_file *file,
  26                                                   void *iter)
  27 {
  28         unsigned int cache_type = (unsigned int)file->private;
  29         struct cache_info *cache;
  30         unsigned int waysize, way, cache_size;
  31         unsigned long ccr, base;
  32         static unsigned long addrstart = 0;
  33
  34         /*
  35          * Go uncached immediately so we don't skew the results any
  36          * more than we already are..
  37          */
  38         jump_to_uncached();
  39
  40         ccr = ctrl_inl(CCR);
  41         if ((ccr & CCR_CACHE_ENABLE) == 0) {
  42                 back_to_cached();
  43
  44                 seq_printf(file, "disabled\n");
  45                 return 0;
  46         }
  47
  48         if (cache_type == CACHE_TYPE_DCACHE) {
  49                 base = CACHE_OC_ADDRESS_ARRAY;
  50                 cache = &current_cpu_data.dcache;
  51         } else {
  52                 base = CACHE_IC_ADDRESS_ARRAY;
  53                 cache = &current_cpu_data.icache;
  54         }
  55
  56         /*
  57          * Due to the amount of data written out (depending on the cache size),
  58          * we may be iterated over multiple times. In this case, keep track of
  59          * the entry position in addrstart, and rewind it when we've hit the
  60          * end of the cache.
  61          *
  62          * Likewise, the same code is used for multiple caches, so care must
  63          * be taken for bouncing addrstart back and forth so the appropriate
  64          * cache is hit.
  65          */
  66         cache_size = cache->ways * cache->sets * cache->linesz;
  67         if (((addrstart & 0xff000000) != base) ||
  68              (addrstart & 0x00ffffff) > cache_size)
  69                 addrstart = base;
  70
  71         waysize = cache->sets;
  72
  73         /*
  74          * If the OC is already in RAM mode, we only have
  75          * half of the entries to consider..
  76          */
  77         if ((ccr & CCR_CACHE_ORA) && cache_type == CACHE_TYPE_DCACHE)
  78                 waysize >>= 1;
  79
  80         waysize <<= cache->entry_shift;
  81
  82         for (way = 0; way < cache->ways; way++) {
  83                 unsigned long addr;
  84                 unsigned int line;
  85
  86                 seq_printf(file, "-----------------------------------------\n");
  87                 seq_printf(file, "Way %d\n", way);
  88                 seq_printf(file, "-----------------------------------------\n");
  89
  90                 for (addr = addrstart, line = 0;
  91                      addr < addrstart + waysize;
  92                      addr += cache->linesz, line++) {
  93                         unsigned long data = ctrl_inl(addr);
  94
  95                         /* Check the V bit, ignore invalid cachelines */
  96                         if ((data & 1) == 0)
  97                                 continue;
  98
  99                         /* U: Dirty, cache tag is 10 bits up */
 100                         seq_printf(file, "%3d: %c 0x%lx\n",
 101                                    line, data & 2 ? 'U' : ' ',
 102                                    data & 0x1ffffc00);
 103                 }
 104
 105                 addrstart += cache->way_incr;
 106         }
 107
 108         back_to_cached();
 109
 110         return 0;
 111 }
 112
 113 static int cache_debugfs_open(struct inode *inode, struct file *file)
 114 {
 115         return single_open(file, cache_seq_show, inode->i_private);
 116 }
 117
 118 static const struct file_operations cache_debugfs_fops = {
 119         .owner          = THIS_MODULE,
 120         .open           = cache_debugfs_open,
 121         .read           = seq_read,
 122         .llseek         = seq_lseek,
 123         .release        = single_release,
 124 };
 125
 126 static int __init cache_debugfs_init(void)
 127 {
 128         struct dentry *dcache_dentry, *icache_dentry;
 129
 130         dcache_dentry = debugfs_create_file("dcache", S_IRUSR, sh_debugfs_root,
 131                                             (unsigned int *)CACHE_TYPE_DCACHE,
 132                                             &cache_debugfs_fops);
 133         if (!dcache_dentry)
 134                 return -ENOMEM;
 135         if (IS_ERR(dcache_dentry))
 136                 return PTR_ERR(dcache_dentry);
 137
 138         icache_dentry = debugfs_create_file("icache", S_IRUSR, sh_debugfs_root,
 139                                             (unsigned int *)CACHE_TYPE_ICACHE,
 140                                             &cache_debugfs_fops);
 141         if (!icache_dentry) {
 142                 debugfs_remove(dcache_dentry);
 143                 return -ENOMEM;
 144         }
 145         if (IS_ERR(icache_dentry)) {
 146                 debugfs_remove(dcache_dentry);
 147                 return PTR_ERR(icache_dentry);
 148         }
 149
 150         return 0;
 151 }
 152 module_init(cache_debugfs_init);
 153
 154 MODULE_LICENSE("GPL v2");