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+#ifndef PPC_POWERNV_IMC_PMU_DEF_H
+#define PPC_POWERNV_IMC_PMU_DEF_H
+
+/*
+ * IMC Nest Performance Monitor counter support.
+ *
+ * Copyright (C) 2016 Madhavan Srinivasan, IBM Corporation.
+ * (C) 2016 Hemant K Shaw, IBM Corporation.
+ *
+ * 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.
+ */
+
+#include <linux/perf_event.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <asm/opal.h>
+
+#define IMC_MAX_CHIPS 32
+#define IMC_MAX_PMUS 32
+#define IMC_MAX_PMU_NAME_LEN 256
+
+#define NEST_IMC_ENGINE_START 1
+#define NEST_IMC_ENGINE_STOP 0
+#define NEST_MAX_PAGES 16
+
+#define NEST_IMC_PRODUCTION_MODE 1
+
+#define IMC_DTB_COMPAT "ibm,opal-in-memory-counters"
+#define IMC_DTB_NEST_COMPAT "ibm,imc-counters-nest"
+
+/*
+ * Structure to hold per chip specific memory address
+ * information for nest pmus. Nest Counter data are exported
+ * in per-chip reserved memory region by the PORE Engine.
+ */
+struct perchip_nest_info {
+ u32 chip_id;
+ u64 pbase;
+ u64 vbase[NEST_MAX_PAGES];
+ u64 size;
+};
+
+/*
+ * Place holder for nest pmu events and values.
+ */
+struct imc_events {
+ char *ev_name;
+ char *ev_value;
+};
+
+/*
+ * Device tree parser code detects IMC pmu support and
+ * registers new IMC pmus. This structure will
+ * hold the pmu functions and attrs for each imc pmu and
+ * will be referenced at the time of pmu registration.
+ */
+struct imc_pmu {
+ struct pmu pmu;
+ int domain;
+ const struct attribute_group *attr_groups[4];
+};
+
+/*
+ * Domains for IMC PMUs
+ */
+#define IMC_DOMAIN_NEST 1
+
+#define UNKNOWN_DOMAIN -1
+
+#endif /* PPC_POWERNV_IMC_PMU_DEF_H */