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+/*
+ * Performance counter support - PowerPC-specific definitions.
+ *
+ * Copyright 2008-2009 Paul Mackerras, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <linux/types.h>
+
+#define MAX_HWCOUNTERS 8
+#define MAX_EVENT_ALTERNATIVES 8
+
+/*
+ * This struct provides the constants and functions needed to
+ * describe the PMU on a particular POWER-family CPU.
+ */
+struct power_pmu {
+ int n_counter;
+ int max_alternatives;
+ u64 add_fields;
+ u64 test_adder;
+ int (*compute_mmcr)(unsigned int events[], int n_ev,
+ unsigned int hwc[], u64 mmcr[]);
+ int (*get_constraint)(unsigned int event, u64 *mskp, u64 *valp);
+ int (*get_alternatives)(unsigned int event, unsigned int alt[]);
+ void (*disable_pmc)(unsigned int pmc, u64 mmcr[]);
+ int n_generic;
+ int *generic_events;
+};
+
+extern struct power_pmu *ppmu;
+
+/*
+ * The power_pmu.get_constraint function returns a 64-bit value and
+ * a 64-bit mask that express the constraints between this event and
+ * other events.
+ *
+ * The value and mask are divided up into (non-overlapping) bitfields
+ * of three different types:
+ *
+ * Select field: this expresses the constraint that some set of bits
+ * in MMCR* needs to be set to a specific value for this event. For a
+ * select field, the mask contains 1s in every bit of the field, and
+ * the value contains a unique value for each possible setting of the
+ * MMCR* bits. The constraint checking code will ensure that two events
+ * that set the same field in their masks have the same value in their
+ * value dwords.
+ *
+ * Add field: this expresses the constraint that there can be at most
+ * N events in a particular class. A field of k bits can be used for
+ * N <= 2^(k-1) - 1. The mask has the most significant bit of the field
+ * set (and the other bits 0), and the value has only the least significant
+ * bit of the field set. In addition, the 'add_fields' and 'test_adder'
+ * in the struct power_pmu for this processor come into play. The
+ * add_fields value contains 1 in the LSB of the field, and the
+ * test_adder contains 2^(k-1) - 1 - N in the field.
+ *
+ * NAND field: this expresses the constraint that you may not have events
+ * in all of a set of classes. (For example, on PPC970, you can't select
+ * events from the FPU, ISU and IDU simultaneously, although any two are
+ * possible.) For N classes, the field is N+1 bits wide, and each class
+ * is assigned one bit from the least-significant N bits. The mask has
+ * only the most-significant bit set, and the value has only the bit
+ * for the event's class set. The test_adder has the least significant
+ * bit set in the field.
+ *
+ * If an event is not subject to the constraint expressed by a particular
+ * field, then it will have 0 in both the mask and value for that field.
+ */