samples/task_profiler: add RTC/counter support as timestamp

On Quark SE, using system timer as event timestamp creates
inconsistencies since the timer is handled by software in
timer_int_handler and tickless_idle_exit. So timestamp does not
reflect timing of certain events like timer IRQ.

This patch introduces the usage of RTC or AON counter as kernel
event logger timestamp

Change-Id: I070254446dd98dd448e119892c34abf12efca719
Signed-off-by: Fabrice Olivero <fabrice.olivero@intel.com>

samples/task_profiler/README.txt

@@ -72,6 +72,9 @@ prof.log = profiler output file generated from Zephyr target (binary)
 1) Enable KERNEL_EVENT_LOGGER
 -----------------------------
 
+  1.1) Kernel event logger configuration
+  --------------------------------------
+
 Edit project configuration file (e.g. $APP_BASE/prj.conf) and add the following
 flags:
 
@@ -108,6 +111,29 @@ If wanting to understand microkernel object usage and task bit handling,
 recommended value is 6
 Otherwise, task monitor can be disabled (to decrease logger ring buffer usage)
 
+  1.2) Kernel event logger timestamp
+  ----------------------------------
+
+By default, the kernel event logger is using the system timer for timestamping
+events. As system timer may not work properly depending on platform, this timer
+can be set at runtime using following flag:
+
+$APP_BASE/prj.conf:
+CONFIG_KERNEL_EVENT_LOGGER_CUSTOM_TIMESTAMP=y
+
+In that case, the profiler will set the RTC as timestamp so RTC must be enabled
+$APP_BASE/prj.conf:
+CONFIG_RTC=y
+
+In case the RTC cannot be used, profiler can support counters as well by
+building application with the following way:
+
+$APP_BASE/prj.conf:
+CONFIG_COUNTER=y
+
+Build command:
+make BOARD=... PROFILER_USE_COUNTER=y
+
 2) Enable UART flush [OPTIONAL]
 -------------------------------
 
@@ -240,6 +266,16 @@ make BOARD=... PROFILER_NO_SHELL_REGISTER=1
 4) Build and flash project
 --------------------------
 
+Flags that can be used by the profiler
+PROFILER_NO_SHELL_REGISTER: when profiler dynamic control is set, the profiler
+                            won't set its own console handler. In that case the
+                            profiler commands must be added to the application
+                            console handler
+
+PROFILER_USECOUNTER: in case custom timestamp is set for the kernel event
+                     logger, the profiler will use RTC. This flag allows to
+                     use a counter instead
+
 5) Get prepared for collecting profiler data
 --------------------------------------------
 

samples/task_profiler/profiler/src/Makefile

@@ -3,5 +3,8 @@ ccflags-y += -I${ZEPHYR_BASE}/include/drivers/
 ifeq (${PROFILER_NO_SHELL_REGISTER},1)
 ccflags-y += -DPROFILER_NO_SHELL_REGISTER
 endif
+ifeq (${PROFILER_USE_COUNTER},1)
+ccflags-y += -DPROFILER_USE_COUNTER
+endif
 
 obj-y = profiler.o

samples/task_profiler/profiler/src/profiler.c

@@ -167,16 +167,72 @@ struct shell_cmd commands[] = {
 	PROF_CMD,
 	{ NULL, NULL}
 };
+#endif /* PROFILER_SHELL */
+
+#undef TIMESTAMP_MODE_RTC
+#undef TIMESTAMP_MODE_COUNTER
+#if defined(CONFIG_KERNEL_EVENT_LOGGER_CUSTOM_TIMESTAMP)
+#if defined(CONFIG_RTC) && !defined(PROFILER_USE_COUNTER)
+#define TIMESTAMP_MODE_RTC
+#elif defined(CONFIG_COUNTER)
+#define TIMESTAMP_MODE_COUNTER
+#else
+#error KERNEL_EVENT_LOGGER_CUSTOM_TIMESTAMP set but RTC/COUNTER not enabled
 #endif
 
+#if defined(TIMESTAMP_MODE_RTC)
+#include <rtc.h>
+struct device *rtc_dev;
+#elif defined(TIMESTAMP_MODE_COUNTER)
+#include <counter.h>
+struct device *counter_dev;
+#endif
+
+#if defined(TIMESTAMP_MODE_RTC)
+uint32_t prof_read_timer(void)
+{
+	return rtc_read(rtc_dev);
+}
+#elif defined(TIMESTAMP_MODE_COUNTER)
+uint32_t prof_read_timer(void)
+{
+	return counter_read(counter_dev);
+}
+#endif
+
+#endif /* CONFIG_KERNEL_EVENT_LOGGER_CUSTOM_TIMESTAMP */
+
 void prof_init(void)
 {
+#if defined(TIMESTAMP_MODE_RTC)
+	struct rtc_config config;
+
+	rtc_dev = device_get_binding("RTC_0");
+	config.init_val = 0;
+	config.alarm_enable = 0;
+	rtc_enable(rtc_dev);
+	rtc_set_config(rtc_dev, &config);
+
+	sys_k_event_logger_set_timer(prof_read_timer);
+#elif defined(TIMESTAMP_MODE_COUNTER)
+	counter_dev = device_get_binding("AON_COUNTER");
+	counter_start(counter_dev);
+
+	sys_k_event_logger_set_timer(prof_read_timer);
+#endif
+
 #ifdef PROFILER_SHELL
 #ifndef PROFILER_NO_SHELL_REGISTER
 	shell_init("shell> ", commands);
 #endif
 #endif
+
+#if defined(TIMESTAMP_MODE_RTC) || defined(TIMESTAMP_MODE_COUNTER)
+	prof_pltfm_info.hw_ticks_per_sec = 32768;
+#else
 	prof_pltfm_info.hw_ticks_per_sec = (sys_clock_ticks_per_sec * sys_clock_hw_cycles_per_tick);
+#endif
+
 	uart_console_dev = device_get_binding(CONFIG_UART_CONSOLE_ON_DEV_NAME);
 
 	prof_initialized = 1;

samples/task_profiler/sample_microkernel_app/prj_quark_se_devboard.conf

@@ -17,3 +17,5 @@ CONFIG_TICKLESS_IDLE=y
 CONFIG_KERNEL_EVENT_LOGGER_SLEEP=y
 CONFIG_UART_QMSI_1_BAUDRATE=2000000
 CONFIG_ARC_INIT=n
+CONFIG_KERNEL_EVENT_LOGGER_CUSTOM_TIMESTAMP=y
+CONFIG_RTC=y

samples/task_profiler/sample_nanokernel_app/prj_quark_se_devboard.conf

@@ -15,3 +15,5 @@ CONFIG_KERNEL_EVENT_LOGGER_INTERRUPT=y
 #CONFIG_KERNEL_EVENT_LOGGER_SLEEP=y
 CONFIG_UART_QMSI_1_BAUDRATE=2000000
 CONFIG_ARC_INIT=n
+CONFIG_KERNEL_EVENT_LOGGER_CUSTOM_TIMESTAMP=y
+CONFIG_RTC=y