From: Dave Olson <ol...@cumulusnetworks.com>
Fix missing L2 cache in /sys/devices/system/cpu/cpu0/cache/index2/size
This appears to have been introduced in 2.6.29 by
93197a36a9c16a85fb24cf5a8639f7bf9af838a3.
This caused lscpu to error out on e500v2 devices, and probably others
error: cannot open /sys/devices/system/cpu/cpu0/cache/index2/size: No such
file or directory
Some embedded powerpc sysystems use cache-size in DTS for the unified L2 cache
size, not d-cache-size, so we need to allow for both DTS names. Added a
new CACHE_TYPE_UNIFIED_D cache_type_info structure to handle this.
Patch is againt URL:
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc.git
master branch (which seems quite old, but is listed as the right branch in the
current Linus
MAINTAINERS file; "next" is also old, "test" is newer, but I wasn't sure I
should use that).
I can rebase, if desired.
Signed-off-by: Dave Olson <ol...@cumulusnetworks.com>
---
diff --git a/arch/powerpc/kernel/cacheinfo.c b/arch/powerpc/kernel/cacheinfo.c
index a3c684b..c3971bc 100644
--- a/arch/powerpc/kernel/cacheinfo.c
+++ b/arch/powerpc/kernel/cacheinfo.c
@@ -62,12 +62,22 @@ struct cache_type_info {
};
/* These are used to index the cache_type_info array. */
-#define CACHE_TYPE_UNIFIED 0
-#define CACHE_TYPE_INSTRUCTION 1
-#define CACHE_TYPE_DATA 2
+#define CACHE_TYPE_UNIFIED 0 /* cache-size, cache-block-size, etc. */
+#define CACHE_TYPE_UNIFIED_D 1 /* d-cache-size, d-cache-block-size, etc */
+#define CACHE_TYPE_INSTRUCTION 2
+#define CACHE_TYPE_DATA 3
static const struct cache_type_info cache_type_info[] = {
{
+ /* Embedded systems that use cache-size, cache-block-size,
+ * etc. for the Unified (typically L2) cache. */
+ .name = "Unified",
+ .size_prop = "cache-size",
+ .line_size_props = { "cache-line-size",
+ "cache-block-size", },
+ .nr_sets_prop = "cache-sets",
+ },
+ {
/* PowerPC Processor binding says the [di]-cache-*
* must be equal on unified caches, so just use
* d-cache properties. */
@@ -293,7 +303,8 @@ static struct cache *cache_find_first_sibling(struct cache
*cache)
{
struct cache *iter;
- if (cache->type == CACHE_TYPE_UNIFIED)
+ if (cache->type == CACHE_TYPE_UNIFIED ||
+ cache->type == CACHE_TYPE_UNIFIED_D)
return cache;
list_for_each_entry(iter, &cache_list, list)
@@ -324,13 +335,31 @@ static bool cache_node_is_unified(const struct
device_node *np)
return of_get_property(np, "cache-unified", NULL);
}
+/*
+ * Handle unified caches that have two different types of tags. Most embedded
+ * use cache-size, etc. for the unified cache size, but open firmware systems
+ * use d-cache-size, etc. Since they all appear to be consistent, check on
+ * initialization for which type we are, and use the appropriate structure.
+ */
static struct cache *__cpuinit cache_do_one_devnode_unified(struct device_node
*node, int level)
{
struct cache *cache;
+ int ucache;
pr_debug("creating L%d ucache for %s\n", level, node->full_name);
- cache = new_cache(CACHE_TYPE_UNIFIED, level, node);
+ if (of_get_property(node,
+ cache_type_info[CACHE_TYPE_UNIFIED_D].size_prop, NULL)) {
+ ucache = CACHE_TYPE_UNIFIED_D;
+ } else {
+ ucache = CACHE_TYPE_UNIFIED; /* assume embedded */
+ if (of_get_property(node,
+ cache_type_info[CACHE_TYPE_UNIFIED].size_prop, NULL) ==
+ NULL)
+ printk(KERN_WARNING "Unified cache property missing\n");
+ }
+
+ cache = new_cache(ucache, level, node);
return cache;
}
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