Add assembler helper to calculate PMF timestamp offset

Given the service name and timestamp id, this assembler macro
calculates the offset into a memory region where the per-cpu timestamp
value is located.

Change-Id: I47f6dfa2a17be182675e2ca0489d6eed42433209

include/lib/pmf/pmf_asm_macros.S

+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __PMF_ASM_MACROS_S__
+#define __PMF_ASM_MACROS_S__
+
+#define PMF_TS_SIZE	8
+
+	/*
+	 * This macro calculates the offset into the memory
+	 * region where the per-cpu timestamp value is stored
+	 * for the given service name and timestamp id.
+	 * Clobbers: x0 - x9
+	 */
+	.macro pmf_calc_timestamp_offset _name _tid
+	mov	x9, x30
+	bl	plat_my_core_pos
+	mov	x30, x9
+	ldr	x1, =__PERCPU_TIMESTAMP_SIZE__
+	mov	x2, #(\_tid * PMF_TS_SIZE)
+	madd	x0, x0, x1, x2
+	ldr	x1, =pmf_ts_mem_\_name
+	add	x0, x0, x1
+	.endm
+
+#endif /* __PMF_ASM_MACROS_S__ */

include/lib/pmf/pmf_helpers.h

@@ -70,7 +70,7 @@ typedef struct pmf_svc_desc {
  * Convenience macro to allocate memory for a PMF service.
  */
 #define PMF_ALLOCATE_TIMESTAMP_MEMORY(_name, _total_id)		\
-	static unsigned long long pmf_ts_mem_ ## _name[_total_id]	\
+	unsigned long long pmf_ts_mem_ ## _name[_total_id]	\
 	__section("pmf_timestamp_array") __used;
 
 /*