separate dptf logic from existing thermal logic.

Signed-off-by: Ravi Chandra Sadineni <ravisadineni@chromium.org>

BRANCH=none
BUG=chromium:631848
TEST=make buildall -j

Change-Id: I718a29b067d37af477306f9bebfcb8e71d84d4ee
Reviewed-on: https://chromium-review.googlesource.com/363008
Commit-Ready: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Duncan Laurie <dlaurie@google.com>

1 files changed, 188 insertions, 0 deletions

diff --git a/common/dptf.c b/common/dptf.c
new file mode 100644
index 0000000000..638427c3b3
--- /dev/null
+++ b/common/dptf.c
@@ -0,0 +1,188 @@
+/* Copyright 2016 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 "atomic.h"
+#include "common.h"
+#include "console.h"
+#include "dptf.h"
+#include "hooks.h"
+#include "host_command.h"
+#include "temp_sensor.h"
+#include "util.h"
+
+/* Console output macros */
+#define CPUTS(outstr) cputs(CC_DPTF, outstr)
+#define CPRINTS(format, args...) cprints(CC_DPTF, format, ## args)
+
+/*****************************************************************************/
+/* DPTF temperature thresholds */
+
+static struct {
+	int temp;     /* degrees K, negative for disabled */
+	cond_t over;      /* watch for crossings */
+} dptf_threshold[TEMP_SENSOR_COUNT][DPTF_THRESHOLDS_PER_SENSOR];
+
+static void dptf_init(void)
+{
+	int id, t;
+
+	for (id = 0; id < TEMP_SENSOR_COUNT; id++)
+		for (t = 0; t < DPTF_THRESHOLDS_PER_SENSOR; t++) {
+			dptf_threshold[id][t].temp = -1;
+			cond_init(&dptf_threshold[id][t].over, 0);
+		}
+
+}
+DECLARE_HOOK(HOOK_INIT, dptf_init, HOOK_PRIO_DEFAULT);
+
+/* Keep track of which triggered sensor thresholds the AP has seen */
+static uint32_t dptf_seen;
+
+int dptf_query_next_sensor_event(void)
+{
+	int id;
+
+	for (id = 0; id < TEMP_SENSOR_COUNT; id++)
+		if (dptf_seen & (1 << id)) {  /* atomic? */
+			atomic_clear(&dptf_seen, (1 << id));
+			return id;
+		}
+
+	return -1;
+}
+
+/* Return true if any threshold transition occurs. */
+static int dpft_check_temp_threshold(int sensor_id, int temp)
+{
+	int tripped = 0;
+	int max, i;
+
+	for (i = 0; i < DPTF_THRESHOLDS_PER_SENSOR; i++) {
+
+		max = dptf_threshold[sensor_id][i].temp;
+		if (max < 0)      /* disabled? */
+			continue;
+
+		if (temp >= max)
+			cond_set_true(&dptf_threshold[sensor_id][i].over);
+		else if (temp <= max - DPTF_THRESHOLD_HYSTERESIS)
+			cond_set_false(&dptf_threshold[sensor_id][i].over);
+
+		if (cond_went_true(&dptf_threshold[sensor_id][i].over)) {
+			CPRINTS("DPTF over threshold [%d][%d",
+				sensor_id, i);
+			atomic_or(&dptf_seen, (1 << sensor_id));
+			tripped = 1;
+		}
+		if (cond_went_false(&dptf_threshold[sensor_id][i].over)) {
+			CPRINTS("DPTF under threshold [%d][%d",
+				sensor_id, i);
+			atomic_or(&dptf_seen, (1 << sensor_id));
+			tripped = 1;
+		}
+	}
+
+	return tripped;
+}
+
+void dptf_set_temp_threshold(int sensor_id, int temp, int idx, int enable)
+{
+	CPRINTS("DPTF sensor %d, threshold %d C, index %d, %sabled",
+		sensor_id, K_TO_C(temp), idx, enable ? "en" : "dis");
+
+	if (enable) {
+		/* Don't update threshold condition if already enabled */
+		if (dptf_threshold[sensor_id][idx].temp == -1)
+			cond_init(&dptf_threshold[sensor_id][idx].over, 0);
+		dptf_threshold[sensor_id][idx].temp = temp;
+		atomic_clear(&dptf_seen, (1 << sensor_id));
+	} else {
+		dptf_threshold[sensor_id][idx].temp = -1;
+	}
+}
+
+/*****************************************************************************/
+/* EC-specific thermal controls */
+
+test_mockable_static void smi_sensor_failure_warning(void)
+{
+	CPRINTS("can't read any temp sensors!");
+	host_set_single_event(EC_HOST_EVENT_THERMAL);
+}
+
+static void thermal_control_dptf(void)
+{
+	int i, t, rv;
+	int dptf_tripped;
+	int num_sensors_read;
+
+	dptf_tripped = 0;
+	num_sensors_read = 0;
+
+	/* go through all the sensors */
+	for (i = 0; i < TEMP_SENSOR_COUNT; ++i) {
+		rv = temp_sensor_read(i, &t);
+		if (rv != EC_SUCCESS)
+			continue;
+		else
+			num_sensors_read++;
+		/* and check the dptf thresholds */
+		dptf_tripped |= dpft_check_temp_threshold(i, t);
+	}
+
+	if (!num_sensors_read) {
+		/*
+		 * Trigger a SMI event if we can't read any sensors.
+		 *
+		 * In theory we could do something more elaborate like forcing
+		 * the system to shut down if no sensors are available after
+		 * several retries.  This is a very unlikely scenario -
+		 * particularly on LM4-based boards, since the LM4 has its own
+		 * internal temp sensor.  It's most likely to occur during
+		 * bringup of a new board, where we haven't debugged the I2C
+		 * bus to the sensors; forcing a shutdown in that case would
+		 * merely hamper board bringup.
+		 */
+		smi_sensor_failure_warning();
+	}
+
+	/* Don't forget to signal any DPTF thresholds */
+	if (dptf_tripped)
+		host_set_single_event(EC_HOST_EVENT_THERMAL_THRESHOLD);
+}
+
+/* Wait until after the sensors have been read */
+DECLARE_HOOK(HOOK_SECOND, thermal_control_dptf, HOOK_PRIO_TEMP_SENSOR_DONE);
+
+/*****************************************************************************/
+/* Console commands */
+
+static int command_dptftemp(int argc, char **argv)
+{
+	int id, t;
+	int temp, trig;
+
+	ccprintf("sensor   thresh0   thresh1\n");
+	for (id = 0; id < TEMP_SENSOR_COUNT; id++) {
+		ccprintf(" %2d", id);
+		for (t = 0; t < DPTF_THRESHOLDS_PER_SENSOR; t++) {
+			temp = dptf_threshold[id][t].temp;
+			trig = cond_is_true(&dptf_threshold[id][t].over);
+			if (temp < 0)
+				ccprintf("       --- ");
+			else
+				ccprintf("       %3d%c", temp,
+					 trig ? '*' : ' ');
+		}
+		ccprintf("    %s\n", temp_sensors[id].name);
+	}
+
+	ccprintf("AP seen mask: 0x%08x\n", dptf_seen);
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(dptftemp, command_dptftemp,
+			NULL,
+			"Print DPTF thermal parameters (degrees Kelvin)",
+			NULL);