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 cache_seq_show(struct seq_file *file, void *iter)
  26 {
  27         unsigned int cache_type = (unsigned int)file->private;
  28         struct cache_info *cache;
  29         unsigned int waysize, way, cache_size;
  30         unsigned long ccr, base;
  31         static unsigned long addrstart = 0;
  32
  33         /*
  34          * Go uncached immediately so we don't skew the results any
  35          * more than we already are..
  36          */
  37         jump_to_P2();
  38
  39         ccr = ctrl_inl(CCR);
  40         if ((ccr & CCR_CACHE_ENABLE) == 0) {
  41                 back_to_P1();
  42
  43                 seq_printf(file, "disabled\n");
  44                 return 0;
  45         }
  46
  47         if (cache_type == CACHE_TYPE_DCACHE) {
  48                 base = CACHE_OC_ADDRESS_ARRAY;
  49                 cache = &current_cpu_data.dcache;
  50         } else {
  51                 base = CACHE_IC_ADDRESS_ARRAY;
  52                 cache = &current_cpu_data.icache;
  53         }
  54
  55         /*
  56          * Due to the amount of data written out (depending on the cache size),
  57          * we may be iterated over multiple times. In this case, keep track of
  58          * the entry position in addrstart, and rewind it when we've hit the
  59          * end of the cache.
  60          *
  61          * Likewise, the same code is used for multiple caches, so care must
  62          * be taken for bouncing addrstart back and forth so the appropriate
  63          * cache is hit.
  64          */
  65         cache_size = cache->ways * cache->sets * cache->linesz;
  66         if (((addrstart & 0xff000000) != base) ||
  67              (addrstart & 0x00ffffff) > cache_size)
  68                 addrstart = base;
  69
  70         waysize = cache->sets;
  71
  72         /*
  73          * If the OC is already in RAM mode, we only have
  74          * half of the entries to consider..
  75          */
  76         if ((ccr & CCR_CACHE_ORA) && cache_type == CACHE_TYPE_DCACHE)
  77                 waysize >>= 1;
  78
  79         waysize <<= cache->entry_shift;
  80
  81         for (way = 0; way < cache->ways; way++) {
  82                 unsigned long addr;
  83                 unsigned int line;
  84
  85                 seq_printf(file, "-----------------------------------------\n");
  86                 seq_printf(file, "Way %d\n", way);
  87                 seq_printf(file, "-----------------------------------------\n");
  88
  89                 for (addr = addrstart, line = 0;
  90                      addr < addrstart + waysize;
  91                      addr += cache->linesz, line++) {
  92                         unsigned long data = ctrl_inl(addr);
  93
  94                         /* Check the V bit, ignore invalid cachelines */
  95                         if ((data & 1) == 0)
  96                                 continue;
  97
  98                         /* U: Dirty, cache tag is 10 bits up */
  99                         seq_printf(file, "%3d: %c 0x%lx\n",
 100                                    line, data & 2 ? 'U' : ' ',
 101                                    data & 0x1ffffc00);
 102                 }
 103
 104                 addrstart += cache->way_incr;
 105         }
 106
 107         back_to_P1();
 108
 109         return 0;
 110 }
 111
 112 static int cache_debugfs_open(struct inode *inode, struct file *file)
 113 {
 114         return single_open(file, cache_seq_show, inode->i_private);
 115 }
 116
 117 static const struct file_operations cache_debugfs_fops = {
 118         .owner          = THIS_MODULE,
 119         .open           = cache_debugfs_open,
 120         .read           = seq_read,
 121         .llseek         = seq_lseek,
 122         .release        = seq_release,
 123 };
 124
 125 static int __init cache_debugfs_init(void)
 126 {
 127         struct dentry *dcache_dentry, *icache_dentry;
 128
 129         dcache_dentry = debugfs_create_file("dcache", S_IRUSR, NULL,
 130                                             (unsigned int *)CACHE_TYPE_DCACHE,
 131                                             &cache_debugfs_fops);
 132         if (IS_ERR(dcache_dentry))
 133                 return PTR_ERR(dcache_dentry);
 134
 135         icache_dentry = debugfs_create_file("icache", S_IRUSR, NULL,
 136                                             (unsigned int *)CACHE_TYPE_ICACHE,
 137                                             &cache_debugfs_fops);
 138         if (IS_ERR(icache_dentry)) {
 139                 debugfs_remove(dcache_dentry);
 140                 return PTR_ERR(icache_dentry);
 141         }
 142
 143         return 0;
 144 }
 145 module_init(cache_debugfs_init);
 146
 147 MODULE_LICENSE("GPL v2");