common: Move fifo logic out of motion_sense.c

This change is needed to allow better testing of the fifo
behavior. Additionally, motion_sense_fifo.c will only be compiled
if CONFIG_ACCEL_FIFO is defined. This behaviour requires a few
small changes to several boards and baseboards to make
sure that we only define CONFIG_ACCEL_FIFO when the MOTIONSENSE
task is present (some times that may be only in one section RW or
RO).

BUG=b:137758297
BRANCH=None
TEST=buildall and ran CTS on arcada

Change-Id: I2f7e4e436ba9568a35b7a0b2c8d53a73f198ba73
Signed-off-by: Yuval Peress <peress@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1704163
Reviewed-by: Alexandru M Stan <amstan@chromium.org>
Commit-Queue: Alexandru M Stan <amstan@chromium.org>

1 files changed, 2 insertions, 407 deletions

diff --git a/common/motion_sense.c b/common/motion_sense.c
index 17806aabfe..424da27011 100644
--- a/common/motion_sense.c
+++ b/common/motion_sense.c
@@ -19,6 +19,7 @@
 #include "math_util.h"
 #include "mkbp_event.h"
 #include "motion_sense.h"
+#include "motion_sense_fifo.h"
 #include "motion_lid.h"
 #include "power.h"
 #include "queue.h"
@@ -63,13 +64,7 @@ static int accel_disp;
  */
 #define MOTION_SENSOR_INT_ADJUSTMENT_US 10
 
-/*
- * Mutex to protect sensor values between host command task and
- * motion sense task:
- * When we process CMD_DUMP, we want to be sure the motion sense
- * task is not updating the sensor values at the same time.
- */
-static struct mutex g_sensor_mutex;
+struct mutex g_sensor_mutex;
 
 /*
  * Current power level (S0, S3, S5, ...)
@@ -83,394 +78,6 @@ static void print_spoof_mode_status(int id);
 /* Flags to control whether to send an ODR change event for a sensor */
 static uint32_t odr_event_required;
 
-#ifdef CONFIG_ACCEL_FIFO
-
-static inline int is_timestamp(struct ec_response_motion_sensor_data *data)
-{
-	return data->flags & MOTIONSENSE_SENSOR_FLAG_TIMESTAMP;
-}
-
-/* Need to wake up the AP */
-static int wake_up_needed;
-
-/* Number of element the AP should collect */
-static int fifo_queue_count;
-static int fifo_int_enabled;
-
-struct queue motion_sense_fifo = QUEUE_NULL(CONFIG_ACCEL_FIFO,
-		struct ec_response_motion_sensor_data);
-static int motion_sense_fifo_lost;
-
-/**
- * Staged metadata for the motion_sense_fifo.
- * @read_ts: The timestamp at which the staged data was read. This value will
- *	serve as the upper bound for spreading
- * @count: The total number of motion_sense_fifo entries that are currently
- *	staged.
- * @sample_count: The total number of sensor readings per sensor that are
- *	currently staged.
- * @requires_spreading: Flag used to shortcut the commit process. This should be
- *	true iff at least one of sample_count[] > 1
- */
-struct fifo_staged {
-	uint32_t read_ts;
-	uint16_t count;
-	uint8_t sample_count[SENSOR_COUNT];
-	uint8_t requires_spreading;
-};
-static struct fifo_staged fifo_staged;
-
-static inline struct ec_response_motion_sensor_data *
-get_motion_sense_fifo_head(void)
-{
-	return ((struct ec_response_motion_sensor_data *)
-		motion_sense_fifo.buffer) +
-	       (motion_sense_fifo.state->head &
-		motion_sense_fifo.unit_bytes);
-}
-
-/**
- * Pop one entry from the motion sense fifo. Poping will give priority to
- * committed data (data residing between the head and tail of the queue). If no
- * committed data is available (all the data is staged), then this function will
- * remove the oldest staged data by moving both the head and tail.
- *
- * As a side-effect of this function, it'll updated any appropriate lost and
- * count variables.
- *
- * WARNING: This function MUST be called from within a locked context of
- * g_sensor_mutex.
- */
-static void motion_sense_fifo_pop(void)
-{
-	struct ec_response_motion_sensor_data *head =
-		get_motion_sense_fifo_head();
-	const size_t initial_count = queue_count(&motion_sense_fifo);
-
-	/* Check that we have something to pop. */
-	if (!initial_count && !fifo_staged.count)
-		return;
-
-	/*
-	 * If all the data is staged (nothing in the committed queue), we'll
-	 * need to move the head and the tail over to simulate poping from the
-	 * staged data.
-	 */
-	if (!initial_count)
-		queue_advance_tail(&motion_sense_fifo, 1);
-
-	/*
-	 * By not using queue_remove_unit we're avoiding an un-necessary memcpy.
-	 */
-	queue_advance_head(&motion_sense_fifo, 1);
-	motion_sense_fifo_lost++;
-
-	/* Increment lost counter if we have valid data. */
-	if (!is_timestamp(head))
-		motion_sensors[head->sensor_num].lost++;
-
-	/*
-	 * We're done if the initial count was non-zero and we only advanced the
-	 * head. Else, decrement the staged count and update staged metadata.
-	 */
-	if (initial_count)
-		return;
-
-	fifo_staged.count--;
-
-	/* If we removed a timestamp there's nothing else for us to do. */
-	if (is_timestamp(head))
-		return;
-
-	/*
-	 * Decrement sample count, if the count was 2 before, we might not need
-	 * to spread anymore. Loop through and check.
-	 */
-	if (--fifo_staged.sample_count[head->sensor_num] < 2) {
-		int i;
-
-		fifo_staged.requires_spreading = 0;
-		for (i = 0; i < SENSOR_COUNT; i++)
-			if (fifo_staged.sample_count[i] > 1) {
-				fifo_staged.requires_spreading = 1;
-				break;
-			}
-	}
-}
-
-static void motion_sense_fifo_ensure_space(void)
-{
-	/* If we already have space just bail. */
-	if (queue_space(&motion_sense_fifo) > fifo_staged.count)
-		return;
-
-	/*
-	 * Pop at least 1 spot, but if all the following conditions are met we
-	 * will continue to pop:
-	 * 1. We're operating with tight timestamps.
-	 * 2. The new head isn't a timestamp.
-	 * 3. We have data that we can possibly pop.
-	 *
-	 * Removing more than one entry is needed because if we are using tight
-	 * timestamps and we pop a timestamp, then the next head is data, the AP
-	 * would assign a bad timestamp to it.
-	 */
-	do {
-		motion_sense_fifo_pop();
-	} while (IS_ENABLED(CONFIG_SENSOR_TIGHT_TIMESTAMPS) &&
-		 !is_timestamp(get_motion_sense_fifo_head()) &&
-		 queue_count(&motion_sense_fifo) + fifo_staged.count);
-}
-
-/*
- * Do not use this function directly if you just want to add sensor data, use
- * motion_sense_fifo_stage_data instead to get a proper timestamp too.
- */
-static void motion_sense_fifo_stage_unit(
-	struct ec_response_motion_sensor_data *data,
-	struct motion_sensor_t *sensor,
-	int valid_data)
-{
-	struct queue_chunk chunk;
-	int i;
-
-	mutex_lock(&g_sensor_mutex);
-
-	for (i = 0; i < valid_data; i++)
-		sensor->xyz[i] = data->data[i];
-
-	/* For valid sensors, check if AP really needs this data */
-	if (valid_data) {
-		int removed;
-
-		if (sensor->oversampling_ratio == 0) {
-			mutex_unlock(&g_sensor_mutex);
-			return;
-		}
-		removed = sensor->oversampling++;
-		sensor->oversampling %= sensor->oversampling_ratio;
-		if (removed != 0) {
-			mutex_unlock(&g_sensor_mutex);
-			return;
-		}
-	}
-
-	/* Make sure we have room for the data */
-	motion_sense_fifo_ensure_space();
-	mutex_unlock(&g_sensor_mutex);
-
-	if (data->flags & MOTIONSENSE_SENSOR_FLAG_WAKEUP)
-		wake_up_needed = 1;
-#ifdef CONFIG_TABLET_MODE
-	data->flags |= (tablet_get_mode() ?
-			MOTIONSENSE_SENSOR_FLAG_TABLET_MODE : 0);
-#endif
-
-	/*
-	 * Get the next writable block in the fifo. We don't need to lock this
-	 * because it will always be past the tail and thus the AP will never
-	 * read this until motion_sense_fifo_commit_data() is called.
-	 */
-	chunk = queue_get_write_chunk(
-			&motion_sense_fifo, fifo_staged.count);
-
-	if (!chunk.buffer) {
-		/*
-		 * This should never happen since we already ensured there was
-		 * space, but if there was a bug, we don't want to write to
-		 * address 0. Just don't add any data to the queue instead.
-		 */
-		CPRINTS("Failed to get write chunk for new fifo data!");
-		return;
-	}
-
-	/*
-	 * Save the data to the writable block and increment count. This data
-	 * will now reside AFTER the tail of the queue and will not be visible
-	 * to the AP until the motion_sense_fifo_commit_data() function is
-	 * called. Because count is incremented, the following staged data will
-	 * be written to the next available block and this one will remain
-	 * staged.
-	 */
-	memcpy(chunk.buffer, data, motion_sense_fifo.unit_bytes);
-	fifo_staged.count++;
-
-	/*
-	 * If we're using tight timestamps, and the current entry isn't a
-	 * timestamp we'll increment the sample_count for the given sensor.
-	 * If the new per-sensor sample count is greater than 1, we'll need to
-	 * spread.
-	 */
-	if (IS_ENABLED(CONFIG_SENSOR_TIGHT_TIMESTAMPS) &&
-			!is_timestamp(data) &&
-			++fifo_staged.sample_count[data->sensor_num] > 1) {
-		fifo_staged.requires_spreading = 1;
-	}
-}
-
-enum motion_sense_async_event {
-	ASYNC_EVENT_FLUSH = MOTIONSENSE_SENSOR_FLAG_FLUSH |
-			    MOTIONSENSE_SENSOR_FLAG_TIMESTAMP,
-	ASYNC_EVENT_ODR =   MOTIONSENSE_SENSOR_FLAG_ODR |
-			    MOTIONSENSE_SENSOR_FLAG_TIMESTAMP,
-};
-
-static void motion_sense_insert_async_event(struct motion_sensor_t *sensor,
-					    enum motion_sense_async_event evt)
-{
-	struct ec_response_motion_sensor_data vector;
-
-	vector.flags = evt;
-	vector.timestamp = __hw_clock_source_read();
-	vector.sensor_num = sensor - motion_sensors;
-
-	motion_sense_fifo_stage_unit(&vector, sensor, 0);
-	motion_sense_fifo_commit_data();
-}
-
-static void motion_sense_fifo_stage_timestamp(uint32_t timestamp)
-{
-	struct ec_response_motion_sensor_data vector;
-
-	vector.flags = MOTIONSENSE_SENSOR_FLAG_TIMESTAMP;
-	vector.timestamp = timestamp;
-	vector.sensor_num = 0;
-	motion_sense_fifo_stage_unit(&vector, NULL, 0);
-}
-
-void motion_sense_fifo_stage_data(struct ec_response_motion_sensor_data *data,
-				  struct motion_sensor_t *sensor,
-				  int valid_data,
-				  uint32_t time)
-{
-	if (IS_ENABLED(CONFIG_SENSOR_TIGHT_TIMESTAMPS)) {
-		/* First entry, save the time for spreading later. */
-		if (!fifo_staged.count)
-			fifo_staged.read_ts = __hw_clock_source_read();
-		motion_sense_fifo_stage_timestamp(time);
-	}
-	motion_sense_fifo_stage_unit(data, sensor, valid_data);
-}
-
-/**
- * Peek into the staged data at a given offset. This function performs no bound
- * checking and is purely for convenience.
- */
-static inline struct ec_response_motion_sensor_data *
-motion_sense_peek_fifo_staged(size_t offset)
-{
-	return (struct ec_response_motion_sensor_data *)
-	       queue_get_write_chunk(&motion_sense_fifo, offset).buffer;
-}
-
-void motion_sense_fifo_commit_data(void)
-{
-	/*
-	 * Static data to use off stack. Note that next_timestamp should persist
-	 * and is only updated if the timestamp from the sensor is greater.
-	 */
-	static uint32_t data_periods[SENSOR_COUNT];
-	static uint32_t next_timestamp[SENSOR_COUNT];
-	struct ec_response_motion_sensor_data *data;
-	int i, window, sensor_num = 0;
-
-	/* Nothing staged, no work to do. */
-	if (!fifo_staged.count)
-		return;
-
-	/*
-	 * If per-sensor event counts are never more than 1, no spreading is
-	 * needed. This will also catch cases where tight timestamps aren't
-	 * used.
-	 */
-	if (!fifo_staged.requires_spreading)
-		goto flush_data_end;
-
-	data = motion_sense_peek_fifo_staged(0);
-
-	/*
-	 * Spreading only makes sense if tight timestamps are used. In such case
-	 * entries are expected to be ordered: timestamp then data. If the first
-	 * entry isn't a timestamp we must have gotten out of sync. Just commit
-	 * all the data and skip the spreading.
-	 */
-	if (!is_timestamp(data)) {
-		CPRINTS("Spreading skipped, first entry is not a timestamp");
-		goto flush_data_end;
-	}
-
-	window = time_until(data->timestamp, fifo_staged.read_ts);
-
-	/* Update the data_periods as needed for this flush. */
-	for (i = 0; i < SENSOR_COUNT; i++) {
-		int period;
-
-		/* Skip empty sensors. */
-		if (!fifo_staged.sample_count[i])
-			continue;
-
-		period = motion_sensors[i].collection_rate;
-		/*
-		 * Clamp the sample period to the MIN of collection_rate and the
-		 * window length / sample counts.
-		 */
-		if (window)
-			period = MIN(period,
-				     window / fifo_staged.sample_count[i]);
-		data_periods[i] = period;
-	}
-
-	/*
-	 * Spread the timestamps.
-	 *
-	 * If we got this far that means that the tight timestamps config is
-	 * enabled. This means that we can expect the staged entries to have 1
-	 * or more timestamps followed by exactly 1 data entry. We'll loop
-	 * through the timestamps until we get to data. We only need to update
-	 * the timestamp right before it to keep things correct.
-	 */
-	for (i = 0; i < fifo_staged.count; i++) {
-		data = motion_sense_peek_fifo_staged(i);
-
-		/* Skip timestamp, we don't know the sensor number yet. */
-		if (is_timestamp(data))
-			continue;
-
-		/* Get the sensor number and point to the timestamp entry. */
-		sensor_num = data->sensor_num;
-		data = motion_sense_peek_fifo_staged(i - 1);
-
-		/* If the timestamp is after our computed next, skip ahead. */
-		if (time_after(data->timestamp, next_timestamp[sensor_num]))
-			next_timestamp[sensor_num] = data->timestamp;
-
-		/* Spread the timestamp and compute the expected next. */
-		data->timestamp = next_timestamp[sensor_num];
-		next_timestamp[sensor_num] += data_periods[sensor_num];
-	}
-
-flush_data_end:
-	/* Advance the tail and clear the staged metadata. */
-	mutex_lock(&g_sensor_mutex);
-	queue_advance_tail(&motion_sense_fifo, fifo_staged.count);
-	mutex_unlock(&g_sensor_mutex);
-
-	/* Reset metadata for next staging cycle. */
-	memset(&fifo_staged, 0, sizeof(fifo_staged));
-}
-
-static void motion_sense_get_fifo_info(
-		struct ec_response_motion_sense_fifo_info *fifo_info)
-{
-	fifo_info->size = motion_sense_fifo.buffer_units;
-	mutex_lock(&g_sensor_mutex);
-	fifo_info->count = fifo_queue_count;
-	fifo_info->total_lost = motion_sense_fifo_lost;
-	mutex_unlock(&g_sensor_mutex);
-	fifo_info->timestamp = mkbp_last_event_time;
-}
-#endif
-
 static inline int motion_sensor_in_forced_mode(
 		const struct motion_sensor_t *sensor)
 {
@@ -1369,18 +976,6 @@ void motion_sense_task(void *u)
 	}
 }
 
-#ifdef CONFIG_ACCEL_FIFO
-static int motion_sense_get_next_event(uint8_t *out)
-{
-	union ec_response_get_next_data *data =
-		(union ec_response_get_next_data *)out;
-	/* out is not padded. It has one byte for the event type */
-	motion_sense_get_fifo_info(&data->sensor_fifo.info);
-	return sizeof(data->sensor_fifo);
-}
-
-DECLARE_EVENT_SOURCE(EC_MKBP_EVENT_SENSOR_FIFO, motion_sense_get_next_event);
-#endif
 /*****************************************************************************/
 /* Host commands */