sh: Add support for cacheline poking through debugfs.
A simple debugging aid for easier visibility of the respective
cachelines.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/mm/cache-debugfs.c b/arch/sh/mm/cache-debugfs.c
new file mode 100644
index 0000000..a22d914
--- /dev/null
+++ b/arch/sh/mm/cache-debugfs.c
@@ -0,0 +1,147 @@
+/*
+ * debugfs ops for the L1 cache
+ *
+ * Copyright (C) 2006 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <asm/processor.h>
+#include <asm/uaccess.h>
+#include <asm/cache.h>
+#include <asm/io.h>
+
+enum cache_type {
+ CACHE_TYPE_ICACHE,
+ CACHE_TYPE_DCACHE,
+ CACHE_TYPE_UNIFIED,
+};
+
+static int cache_seq_show(struct seq_file *file, void *iter)
+{
+ unsigned int cache_type = (unsigned int)file->private;
+ struct cache_info *cache;
+ unsigned int waysize, way, cache_size;
+ unsigned long ccr, base;
+ static unsigned long addrstart = 0;
+
+ /*
+ * Go uncached immediately so we don't skew the results any
+ * more than we already are..
+ */
+ jump_to_P2();
+
+ ccr = ctrl_inl(CCR);
+ if ((ccr & CCR_CACHE_ENABLE) == 0) {
+ back_to_P1();
+
+ seq_printf(file, "disabled\n");
+ return 0;
+ }
+
+ if (cache_type == CACHE_TYPE_DCACHE) {
+ base = CACHE_OC_ADDRESS_ARRAY;
+ cache = &cpu_data->dcache;
+ } else {
+ base = CACHE_IC_ADDRESS_ARRAY;
+ cache = &cpu_data->icache;
+ }
+
+ /*
+ * Due to the amount of data written out (depending on the cache size),
+ * we may be iterated over multiple times. In this case, keep track of
+ * the entry position in addrstart, and rewind it when we've hit the
+ * end of the cache.
+ *
+ * Likewise, the same code is used for multiple caches, so care must
+ * be taken for bouncing addrstart back and forth so the appropriate
+ * cache is hit.
+ */
+ cache_size = cache->ways * cache->sets * cache->linesz;
+ if (((addrstart & 0xff000000) != base) ||
+ (addrstart & 0x00ffffff) > cache_size)
+ addrstart = base;
+
+ waysize = cache->sets;
+
+ /*
+ * If the OC is already in RAM mode, we only have
+ * half of the entries to consider..
+ */
+ if ((ccr & CCR_CACHE_ORA) && cache_type == CACHE_TYPE_DCACHE)
+ waysize >>= 1;
+
+ waysize <<= cache->entry_shift;
+
+ for (way = 0; way < cache->ways; way++) {
+ unsigned long addr;
+ unsigned int line;
+
+ seq_printf(file, "-----------------------------------------\n");
+ seq_printf(file, "Way %d\n", way);
+ seq_printf(file, "-----------------------------------------\n");
+
+ for (addr = addrstart, line = 0;
+ addr < addrstart + waysize;
+ addr += cache->linesz, line++) {
+ unsigned long data = ctrl_inl(addr);
+
+ /* Check the V bit, ignore invalid cachelines */
+ if ((data & 1) == 0)
+ continue;
+
+ /* U: Dirty, cache tag is 10 bits up */
+ seq_printf(file, "%3d: %c 0x%lx\n",
+ line, data & 2 ? 'U' : ' ',
+ data & 0x1ffffc00);
+ }
+
+ addrstart += cache->way_incr;
+ }
+
+ back_to_P1();
+
+ return 0;
+}
+
+static int cache_debugfs_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, cache_seq_show, inode->u.generic_ip);
+}
+
+static struct file_operations cache_debugfs_fops = {
+ .owner = THIS_MODULE,
+ .open = cache_debugfs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init cache_debugfs_init(void)
+{
+ struct dentry *dcache_dentry, *icache_dentry;
+
+ dcache_dentry = debugfs_create_file("dcache", S_IRUSR, NULL,
+ (unsigned int *)CACHE_TYPE_DCACHE,
+ &cache_debugfs_fops);
+ if (IS_ERR(dcache_dentry))
+ return PTR_ERR(dcache_dentry);
+
+ icache_dentry = debugfs_create_file("icache", S_IRUSR, NULL,
+ (unsigned int *)CACHE_TYPE_ICACHE,
+ &cache_debugfs_fops);
+ if (IS_ERR(icache_dentry)) {
+ debugfs_remove(dcache_dentry);
+ return PTR_ERR(icache_dentry);
+ }
+
+ return 0;
+}
+module_init(cache_debugfs_init);
+
+MODULE_LICENSE("GPL v2");