arch: nios2: add timing implementation

Add timing implementation for NIOS2 architecture.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

arch/Kconfig

@@ -55,6 +55,7 @@ config NIOS2
 	select ATOMIC_OPERATIONS_C
 	select HAS_DTS
 	imply XIP
+	select ARCH_HAS_TIMING_FUNCTIONS
 	help
 	  Nios II Gen 2 architecture
 

arch/nios2/core/CMakeLists.txt

@@ -16,3 +16,4 @@ zephyr_library_sources(
   )
 
 zephyr_library_sources_ifdef(CONFIG_IRQ_OFFLOAD irq_offload.c)
+zephyr_library_sources_ifdef(CONFIG_TIMING_FUNCTIONS timing.c)

arch/nios2/core/timing.c

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2020 Intel Corporation.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <kernel.h>
+#include <sys_clock.h>
+#include <timing/timing.h>
+#include "altera_avalon_timer_regs.h"
+
+#define NIOS2_SUBTRACT_CLOCK_CYCLES(val)                                       \
+	((IORD_ALTERA_AVALON_TIMER_PERIODH(TIMER_0_BASE) << 16 |               \
+	  (IORD_ALTERA_AVALON_TIMER_PERIODL(TIMER_0_BASE))) -                  \
+	 ((uint32_t)val))
+
+#define TIMING_INFO_OS_GET_TIME()                                              \
+	(NIOS2_SUBTRACT_CLOCK_CYCLES(                                          \
+		((uint32_t)IORD_ALTERA_AVALON_TIMER_SNAPH(TIMER_0_BASE)        \
+		 << 16) |                                                      \
+		((uint32_t)IORD_ALTERA_AVALON_TIMER_SNAPL(TIMER_0_BASE))))
+
+void timing_init(void)
+{
+}
+
+void timing_start(void)
+{
+}
+
+void timing_stop(void)
+{
+}
+
+timing_t timing_counter_get(void)
+{
+	IOWR_ALTERA_AVALON_TIMER_SNAPL(TIMER_0_BASE, 10);
+	return TIMING_INFO_OS_GET_TIME();
+}
+
+uint64_t timing_cycles_get(volatile timing_t *const start,
+				  volatile timing_t *const end)
+{
+	return (*end - *start);
+}
+
+uint64_t timing_freq_get(void)
+{
+	return sys_clock_hw_cycles_per_sec();
+}
+
+uint64_t timing_cycles_to_ns(uint64_t cycles)
+{
+	return k_cyc_to_ns_floor64(cycles);
+}
+
+uint64_t timing_cycles_to_ns_avg(uint64_t cycles, uint32_t count)
+{
+	return timing_cycles_to_ns(cycles) / count;
+}
+
+uint32_t timing_freq_get_mhz(void)
+{
+	return (uint32_t)(timing_freq_get() / 1000000);
+}