From: Sudeep Holla <redacted>

This patch adds initial support for providing processor cache information
to userspace through sysfs interface. This is based on x86 implementation
and hence the interface is intended to be fully compatible.

A per-cpu array of cache information maintained is used mainly for
sysfs-related book keeping.

Signed-off-by: Sudeep Holla <redacted>
---
 drivers/base/Makefile     |   2 +-
 drivers/base/cacheinfo.c  | 296 ++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/cacheinfo.h |  43 +++++++
 3 files changed, 340 insertions(+), 1 deletion(-)
 create mode 100644 drivers/base/cacheinfo.c
 create mode 100644 include/linux/cacheinfo.h

diff --git a/drivers/base/Makefile b/drivers/base/Makefile
index 94e8a80..76f07c8 100644
--- a/drivers/base/Makefile
+++ b/drivers/base/Makefile

@@ -4,7 +4,7 @@ obj-y			:= core.o bus.o dd.o syscore.o \
 			   driver.o class.o platform.o \
 			   cpu.o firmware.o init.o map.o devres.o \
 			   attribute_container.o transport_class.o \
-			   topology.o
+			   topology.o cacheinfo.o
 obj-$(CONFIG_DEVTMPFS)	+= devtmpfs.o
 obj-$(CONFIG_DMA_CMA) += dma-contiguous.o
 obj-y			+= power/

diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
new file mode 100644
index 0000000..f436c31
--- /dev/null
+++ b/drivers/base/cacheinfo.c

@@ -0,0 +1,296 @@
+/*
+ * cacheinfo support - processor cache information via sysfs
+ *
+ * Copyright (C) 2013 ARM Ltd.
+ * All Rights Reserved
+ *
+ * Author: Sudeep Holla <sudeep.holla@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <linux/bitops.h>
+#include <linux/cacheinfo.h>
+#include <linux/compiler.h>
+#include <linux/cpu.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kobject.h>
+#include <linux/of.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+#include <linux/sysfs.h>
+
+struct cache_attr {
+	struct attribute attr;
+	 ssize_t(*show) (unsigned int, unsigned short, char *);
+	 ssize_t(*store) (unsigned int, unsigned short, const char *, size_t);
+};
+
+/* pointer to kobject for cpuX/cache */
+static DEFINE_PER_CPU(struct kobject *, ci_cache_kobject);
+#define per_cpu_cache_kobject(cpu)     (per_cpu(ci_cache_kobject, cpu))
+
+struct index_kobject {
+	struct kobject kobj;
+	unsigned int cpu;
+	unsigned short index;
+};
+
+static cpumask_t cache_dev_map;
+
+/* pointer to array of kobjects for cpuX/cache/indexY */