gimble: add custom fan control

BUG=b:195378817
BRANCH=none
TEST=make -j BOARD=gimble

Signed-off-by: Will Tsai <will_tsai@wistron.corp-partner.google.com>
Change-Id: Id6a5119d16291beb34dcc7da8f48d668f47b5297
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3067287
Reviewed-by: Boris Mittelberg <bmbm@google.com>

3 files changed, 152 insertions, 1 deletions

diff --git a/board/gimble/board.h b/board/gimble/board.h
index 514b3ce4f8..bf5edeca9f 100644
--- a/board/gimble/board.h
+++ b/board/gimble/board.h
@@ -155,6 +155,7 @@
 #undef CONFIG_USBC_RETIMER_FW_UPDATE
 
 /* Thermal features */
+#define CONFIG_FANS FAN_CH_COUNT
 #define CONFIG_THERMISTOR
 #define CONFIG_TEMP_SENSOR
 #define CONFIG_TEMP_SENSOR_POWER_GPIO	GPIO_SEQ_EC_DSW_PWROK
@@ -167,7 +168,8 @@
 /*
  * TODO(b/181271666): no fan control loop until sensors are tuned
  */
-/* #define CONFIG_FANS			FAN_CH_COUNT */
+/* Fan features */
+#define CONFIG_CUSTOM_FAN_CONTROL
 
 /* Charger defines */
 #define CONFIG_CHARGER_BQ25720
diff --git a/board/gimble/build.mk b/board/gimble/build.mk
index 1faa2d917d..9ec302a7d9 100644
--- a/board/gimble/build.mk
+++ b/board/gimble/build.mk
@@ -21,4 +21,5 @@ board-y+=keyboard.o
 board-y+=led.o
 board-y+=pwm.o
 board-y+=sensors.o
+board-y+=thermal.o
 board-y+=usbc_config.o
diff --git a/board/gimble/thermal.c b/board/gimble/thermal.c
new file mode 100644
index 0000000000..101c436886
--- /dev/null
+++ b/board/gimble/thermal.c
@@ -0,0 +1,148 @@
+/* Copyright 2021 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "chipset.h"
+#include "common.h"
+#include "console.h"
+#include "fan.h"
+#include "hooks.h"
+#include "host_command.h"
+#include "temp_sensor.h"
+#include "thermal.h"
+#include "util.h"
+/* Console output macros */
+#define CPUTS(outstr) cputs(CC_THERMAL, outstr)
+#define CPRINTS(format, args...) cprints(CC_THERMAL, format, ## args)
+
+
+
+struct fan_step {
+	/*
+	 * Sensor 1~4 trigger point, set -1 if we're not using this
+	 * sensor to determine fan speed.
+	 */
+	int8_t on[TEMP_SENSOR_COUNT];
+	/*
+	 * Sensor 1~4 trigger point, set -1 if we're not using this
+	 * sensor to determine fan speed.
+	 */
+	int8_t off[TEMP_SENSOR_COUNT];
+	/* Fan rpm */
+	uint16_t rpm[FAN_CH_COUNT];
+};
+/*
+ * TODO(b/167931578) Only monitor sensor3 for now.
+ * Will add more sensors support if needed.
+ */
+static const struct fan_step fan_table[] = {
+	{
+		/* level 0 */
+		.on = {44, -1, -1},
+		.off = {0, -1, -1},
+		.rpm = {0},
+	},
+	{
+		/* level 1 */
+		.on = {46, -1, -1},
+		.off = {44, -1, -1},
+		.rpm = {3200},
+	},
+	{
+		/* level 2 */
+		.on = {50, -1, -1},
+		.off = {45, -1, -1},
+		.rpm = {3600},
+	},
+	{
+		/* level 3 */
+		.on = {54, -1, -1},
+		.off = {49, -1, -1},
+		.rpm = {4100},
+	},
+	{
+		/* level 4 */
+		.on = {58, -1, -1},
+		.off = {53, -1, -1},
+		.rpm = {4900},
+	},
+	{
+		/* level 5 */
+		.on = {60, -1, -1},
+		.off = {57, -1, -1},
+		.rpm = {5200},
+	},
+};
+const int num_fan_levels = ARRAY_SIZE(fan_table);
+
+int fan_table_to_rpm(int fan, int *temp, enum temp_sensor_id temp_sensor)
+{
+	/* current fan level */
+	static int current_level;
+	/* previous fan level */
+	static int prev_current_level;
+
+	/* previous sensor temperature */
+	static int prev_temp[TEMP_SENSOR_COUNT];
+	int i;
+	int new_rpm = 0;
+
+	/*
+	 * Compare the current and previous temperature, we have
+	 * the three paths :
+	 *  1. decreasing path. (check the release point)
+	 *  2. increasing path. (check the trigger point)
+	 *  3. invariant path. (return the current RPM)
+	 */
+	if (temp[temp_sensor] < prev_temp[temp_sensor]) {
+		for (i = current_level; i > 0; i--) {
+			if (temp[temp_sensor] <
+				fan_table[i].off[temp_sensor])
+				current_level = i - 1;
+			else
+				break;
+		}
+	} else if (temp[temp_sensor] >
+		prev_temp[temp_sensor]) {
+		for (i = current_level; i < num_fan_levels; i++) {
+			if (temp[temp_sensor] >
+				fan_table[i].on[temp_sensor])
+				current_level = i + 1;
+			else
+				break;
+		}
+	}
+	if (current_level < 0)
+		current_level = 0;
+
+	if (current_level != prev_current_level) {
+		CPRINTS("temp: %d, prev_temp: %d", temp[temp_sensor],
+			prev_temp[temp_sensor]);
+		CPRINTS("current_level: %d", current_level);
+	}
+
+	prev_temp[temp_sensor] = temp[temp_sensor];
+	prev_current_level = current_level;
+
+	switch (fan) {
+	case FAN_CH_0:
+		new_rpm = fan_table[current_level].rpm[FAN_CH_0];
+		break;
+	default:
+		break;
+	}
+	return new_rpm;
+}
+void board_override_fan_control(int fan, int *temp)
+{
+	if (chipset_in_state(CHIPSET_STATE_ON)) {
+		fan_set_rpm_mode(FAN_CH(fan), 1);
+		fan_set_rpm_target(FAN_CH(fan),
+			fan_table_to_rpm(FAN_CH(fan), temp, TEMP_SENSOR_1_DDR_SOC));
+	} else if (chipset_in_state(CHIPSET_STATE_ANY_SUSPEND)) {
+		/* Stop fan when enter S0ix */
+		fan_set_rpm_mode(FAN_CH(fan), 1);
+		fan_set_rpm_target(FAN_CH(fan), 0);
+	}
+}