[V7,1/4] sensors: occ: Add support for OCC inband sensors

Message ID 1498820345-1486-2-git-send-email-shilpa.bhat@linux.vnet.ibm.com
State Superseded
Headers show

Commit Message

Shilpasri G Bhat June 30, 2017, 10:59 a.m.
Add support to parse and export OCC inband sensors which are copied
by OCC to main memory in P9. Each OCC writes three buffers which
includes one names buffer for sensor meta data and two buffers for
sensor readings. While OCC writes to one buffer the sensor values
can be read from the other buffer. The sensors are updated every
100ms.

This patch adds power, temperature, current and voltage sensors to
/ibm,opal/sensors device-tree node which can be exported by the
ibmpowernv-hwmon driver in Linux.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Reviewed-by: C├ędric Le Goater <clg@kaod.org>
---
- Rebased on skiboot master

 core/init.c       |   1 +
 core/sensor.c     |   4 +
 hw/Makefile.inc   |   2 +-
 hw/occ-sensor.c   | 596 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/sensor.h  |   1 +
 include/skiboot.h |   4 +
 6 files changed, 607 insertions(+), 1 deletion(-)
 create mode 100644 hw/occ-sensor.c

Patch

diff --git a/core/init.c b/core/init.c
index c58ef3a..14dbd9c 100644
--- a/core/init.c
+++ b/core/init.c
@@ -507,6 +507,7 @@  void __noreturn load_and_boot_kernel(bool is_reboot)
 	 * as possible to avoid delay.
 	 */
 	occ_pstates_init();
+	occ_sensors_init();
 
 	/* Use nvram bootargs over device tree */
 	cmdline = nvram_query("bootargs");
diff --git a/core/sensor.c b/core/sensor.c
index cc5341c..b0d3c5e 100644
--- a/core/sensor.c
+++ b/core/sensor.c
@@ -29,6 +29,10 @@  static int64_t opal_sensor_read(uint32_t sensor_hndl, int token,
 	switch (sensor_get_family(sensor_hndl)) {
 	case SENSOR_DTS:
 		return dts_sensor_read(sensor_hndl, sensor_data);
+	case SENSOR_OCC:
+		return occ_sensor_read(sensor_hndl, sensor_data);
+	default:
+		break;
 	}
 
 	if (platform.sensor_read)
diff --git a/hw/Makefile.inc b/hw/Makefile.inc
index f22f0e8..f0fb4ad 100644
--- a/hw/Makefile.inc
+++ b/hw/Makefile.inc
@@ -7,7 +7,7 @@  HW_OBJS += p7ioc.o p7ioc-inits.o p7ioc-phb.o
 HW_OBJS += phb3.o sfc-ctrl.o fake-rtc.o bt.o p8-i2c.o prd.o
 HW_OBJS += dts.o lpc-rtc.o npu.o npu-hw-procedures.o xive.o phb4.o
 HW_OBJS += fake-nvram.o lpc-mbox.o npu2.o npu2-hw-procedures.o
-HW_OBJS += phys-map.o sbe-p9.o capp.o
+HW_OBJS += phys-map.o sbe-p9.o capp.o occ-sensor.o
 HW=hw/built-in.o
 
 # FIXME hack this for now
diff --git a/hw/occ-sensor.c b/hw/occ-sensor.c
new file mode 100644
index 0000000..75f00d5
--- /dev/null
+++ b/hw/occ-sensor.c
@@ -0,0 +1,596 @@ 
+/* Copyright 2017 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *	http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <skiboot.h>
+#include <opal.h>
+#include <chip.h>
+#include <sensor.h>
+#include <device.h>
+
+/*
+ * OCC Sensor Data
+ *
+ * OCC sensor data will use BAR2 (OCC Common is per physical drawer).
+ * Starting address is at offset 0x00580000 from BAR2 base address.
+ * Maximum size is 1.5MB.
+ *
+ * -------------------------------------------------------------------------
+ * | Start (Offset from |	End	| Size	   |Description		   |
+ * | BAR2 base address) |		|	   |			   |
+ * -------------------------------------------------------------------------
+ * |	0x00580000      |  0x005A57FF   |150kB     |OCC 0 Sensor Data Block|
+ * |	0x005A5800      |  0x005CAFFF   |150kB	   |OCC 1 Sensor Data Block|
+ * |	    :		|	:	|  :	   |		:          |
+ * |	0x00686800	|  0x006ABFFF   |150kB	   |OCC 7 Sensor Data Block|
+ * |	0x006AC000	|  0x006FFFFF   |336kB     |Reserved		   |
+ * -------------------------------------------------------------------------
+ *
+ *
+ * OCC N Sensor Data Block Layout (150kB)
+ *
+ * The sensor data block layout is the same for each OCC N. It contains
+ * sensor-header-block, sensor-names buffer, sensor-readings-ping buffer and
+ * sensor-readings-pong buffer.
+ *
+ * ----------------------------------------------------------------------------
+ * | Start (Offset from OCC |   End	   | Size |Description		      |
+ * | N Sensor Data Block)   |		   |	  |			      |
+ * ----------------------------------------------------------------------------
+ * |	0x00000000	    |  0x000003FF  |1kB   |Sensor Data Header Block   |
+ * |	0x00000400	    |  0x0000CBFF  |50kB  |Sensor Names		      |
+ * |	0x0000CC00	    |  0x0000DBFF  |4kB   |Reserved		      |
+ * |	0x0000DC00	    |  0x00017BFF  |40kB  |Sensor Readings ping buffer|
+ * |	0x00017C00	    |  0x00018BFF  |4kB   |Reserved		      |
+ * |	0x00018C00	    |  0x00022BFF  |40kB  |Sensor Readings pong buffer|
+ * |	0x00022C00	    |  0x000257FF  |11kB  |Reserved		      |
+ * ----------------------------------------------------------------------------
+ *
+ * Sensor Data Header Block : This is written once by the OCC during
+ * initialization after a load or reset. Layout is defined in 'struct
+ * occ_sensor_data_header'
+ *
+ * Sensor Names : This is written once by the OCC during initialization after a
+ * load or reset. It contains static information for each sensor. The number of
+ * sensors, format version and length of each sensor is defined in
+ * 'Sensor Data Header Block'. Format of each sensor name is defined in
+ * 'struct occ_sensor_name'. The first sensor starts at offset 0 followed
+ * immediately by the next sensor.
+ *
+ * Sensor Readings Ping/Pong Buffer:
+ * There are two 40kB buffers to store the sensor readings. One buffer that
+ * is currently being updated by the OCC and one that is available to be read.
+ * Each of these buffers will be of the same format. The number of sensors and
+ * the format version of the ping and pong buffers is defined in the
+ * 'Sensor Data Header Block'.
+ *
+ * Each sensor within the ping and pong buffers may be of a different format
+ * and length. For each sensor the length and format is determined by its
+ * 'struct occ_sensor_name.structure_type' in the Sensor Names buffer.
+ *
+ * --------------------------------------------------------------------------
+ * | Offset | Byte0 | Byte1 | Byte2 | Byte3 | Byte4 | Byte5 | Byte6 | Byte7 |
+ * --------------------------------------------------------------------------
+ * | 0x0000 |Valid  |		   Reserved				    |
+ * |        |(0x01) |							    |
+ * --------------------------------------------------------------------------
+ * | 0x0008 |			Sensor Readings				    |
+ * --------------------------------------------------------------------------
+ * |	:   |				:				    |
+ * --------------------------------------------------------------------------
+ * | 0xA000 |                     End of Data				    |
+ * --------------------------------------------------------------------------
+ *
+ */
+
+#define MAX_OCCS			8
+#define MAX_CHARS_SENSOR_NAME		16
+#define MAX_CHARS_SENSOR_UNIT		4
+
+#define OCC_SENSOR_DATA_BLOCK_OFFSET		0x00580000
+#define OCC_SENSOR_DATA_BLOCK_SIZE		0x00025800
+
+enum occ_sensor_type {
+	OCC_SENSOR_TYPE_GENERIC		= 0x0001,
+	OCC_SENSOR_TYPE_CURRENT		= 0x0002,
+	OCC_SENSOR_TYPE_VOLTAGE		= 0x0004,
+	OCC_SENSOR_TYPE_TEMPERATURE	= 0x0008,
+	OCC_SENSOR_TYPE_UTILIZATION	= 0x0010,
+	OCC_SENSOR_TYPE_TIME		= 0x0020,
+	OCC_SENSOR_TYPE_FREQUENCY	= 0x0040,
+	OCC_SENSOR_TYPE_POWER		= 0x0080,
+	OCC_SENSOR_TYPE_PERFORMANCE	= 0x0200,
+};
+
+enum occ_sensor_location {
+	OCC_SENSOR_LOC_SYSTEM		= 0x0001,
+	OCC_SENSOR_LOC_PROCESSOR	= 0x0002,
+	OCC_SENSOR_LOC_PARTITION	= 0x0004,
+	OCC_SENSOR_LOC_MEMORY		= 0x0008,
+	OCC_SENSOR_LOC_VRM		= 0x0010,
+	OCC_SENSOR_LOC_OCC		= 0x0020,
+	OCC_SENSOR_LOC_CORE		= 0x0040,
+	OCC_SENSOR_LOC_QUAD		= 0x0080,
+	OCC_SENSOR_LOC_GPU		= 0x0100,
+};
+
+enum sensor_struct_type {
+	OCC_SENSOR_READING_FULL		= 0x01,
+	OCC_SENSOR_READING_COUNTER	= 0x02,
+};
+
+/**
+ * struct occ_sensor_data_header -	Sensor Data Header Block
+ * @valid:				When the value is 0x01 it indicates
+ *					that this header block and the sensor
+ *					names buffer are ready
+ * @version:				Format version of this block
+ * @nr_sensors:				Number of sensors in names, ping and
+ *					pong buffer
+ * @reading_version:			Format version of the Ping/Pong buffer
+ * @names_offset:			Offset to the location of names buffer
+ * @names_version:			Format version of names buffer
+ * @names_length:			Length of each sensor in names buffer
+ * @reading_ping_offset:		Offset to the location of Ping buffer
+ * @reading_pong_offset:		Offset to the location of Pong buffer
+ * @pad/reserved:			Unused data
+ */
+struct occ_sensor_data_header {
+	u8 valid;
+	u8 version;
+	u16 nr_sensors;
+	u8 reading_version;
+	u8 pad[3];
+	u32 names_offset;
+	u8 names_version;
+	u8 name_length;
+	u16 reserved;
+	u32 reading_ping_offset;
+	u32 reading_pong_offset;
+} __packed;
+
+/**
+ * struct occ_sensor_name -		Format of Sensor Name
+ * @name:				Sensor name
+ * @units:				Sensor units of measurement
+ * @gsid:				Global sensor id (OCC)
+ * @freq:				Update frequency
+ * @scale_factor:			Scaling factor
+ * @type:				Sensor type as defined in
+ *					'enum occ_sensor_type'
+ * @location:				Sensor location as defined in
+ *					'enum occ_sensor_location'
+ * @structure_type:			Indicates type of data structure used
+ *					for the sensor readings in the ping and
+ *					pong buffers for this sensor as defined
+ *					in 'enum sensor_struct_type'
+ * @reading_offset:			Offset from the start of the ping/pong
+ *					reading buffers for this sensor
+ * @sensor_data:			Sensor specific info
+ * @pad:				Padding to fit the size of 48 bytes.
+ */
+struct occ_sensor_name {
+	char name[MAX_CHARS_SENSOR_NAME];
+	char units[MAX_CHARS_SENSOR_UNIT];
+	u16 gsid;
+	u32 freq;
+	u32 scale_factor;
+	u16 type;
+	u16 location;
+	u8 structure_type;
+	u32 reading_offset;
+	u8 sensor_data;
+	u8 pad[8];
+} __packed;
+
+/**
+ * struct occ_sensor_record -		Sensor Reading Full
+ * @gsid:				Global sensor id (OCC)
+ * @timestamp:				Time base counter value while updating
+ *					the sensor
+ * @sample:				Latest sample of this sensor
+ * @sample_min:				Minimum value since last OCC reset
+ * @sample_max:				Maximum value since last OCC reset
+ * @CSM_min:				Minimum value since last reset request
+ *					by CSM (CORAL)
+ * @CSM_max:				Maximum value since last reset request
+ *					by CSM (CORAL)
+ * @profiler_min:			Minimum value since last reset request
+ *					by profiler (CORAL)
+ * @profiler_max:			Maximum value since last reset request
+ *					by profiler (CORAL)
+ * @job_scheduler_min:			Minimum value since last reset request
+ *					by job scheduler(CORAL)
+ * @job_scheduler_max:			Maximum value since last reset request
+ *					by job scheduler (CORAL)
+ * @accumulator:			Accumulator for this sensor
+ * @update_tag:				Count of the number of ticks that have
+ *					passed between updates
+ * @pad:				Padding to fit the size of 48 bytes
+ */
+struct occ_sensor_record {
+	u16 gsid;
+	u64 timestamp;
+	u16 sample;
+	u16 sample_min;
+	u16 sample_max;
+	u16 CSM_min;
+	u16 CSM_max;
+	u16 profiler_min;
+	u16 profiler_max;
+	u16 job_scheduler_min;
+	u16 job_scheduler_max;
+	u64 accumulator;
+	u32 update_tag;
+	u8 pad[8];
+} __packed;
+
+/**
+ * struct occ_sensor_counter -		Sensor Reading Counter
+ * @gsid:				Global sensor id (OCC)
+ * @timestamp:				Time base counter value while updating
+ *					the sensor
+ * @accumulator:			Accumulator/Counter
+ * @sample:				Latest sample of this sensor (0/1)
+ * @pad:				Padding to fit the size of 24 bytes
+ */
+struct occ_sensor_counter {
+	u16 gsid;
+	u64 timestamp;
+	u64 accumulator;
+	u8 sample;
+	u8 pad[5];
+} __packed;
+
+enum sensor_attr {
+	SENSOR_SAMPLE,
+	SENSOR_MAX,
+	SENSOR_MIN,
+	MAX_SENSOR_ATTR,
+};
+
+#define HWMON_SENSORS_MASK	(OCC_SENSOR_TYPE_CURRENT | \
+				 OCC_SENSOR_TYPE_VOLTAGE | \
+				 OCC_SENSOR_TYPE_TEMPERATURE | \
+				 OCC_SENSOR_TYPE_POWER)
+
+static struct str_map {
+	const char *occ_str;
+	const char *opal_str;
+} str_maps[] = {
+	{"PWRSYS", "System"},
+	{"PWRFAN", "Fan"},
+	{"PWRIO", "IO"},
+	{"PWRSTORE", "Storage"},
+	{"PWRGPU", "GPU"},
+	{"PWRAPSSCH", "APSS"},
+	{"PWRPROC", ""},
+	{"PWRVDD", "Vdd"},
+	{"CURVDD", "Vdd"},
+	{"VOLTVDDSENSE", "Vdd Remote Sense"},
+	{"VOLTVDD", "Vdd"},
+	{"PWRVDN", "Vdn"},
+	{"CURVDN", "Vdn"},
+	{"VOLTVDNSENSE", "Vdn Remote Sense"},
+	{"VOLTVDN", "Vdn"},
+	{"PWRMEM", "Memory"},
+	{"TEMPC", "Core"},
+	{"TEMPQ", "Quad"},
+	{"TEMPNEST", "Nest"},
+	{"TEMPPROCTHRM", "Chip"},
+	{"TEMPDIMM", "DIMM"},
+	{"TEMPGPU", "GPU"},
+};
+
+static u64 occ_sensor_base;
+
+static inline
+struct occ_sensor_data_header *get_sensor_header_block(int occ_num)
+{
+	return (struct occ_sensor_data_header *)
+		(occ_sensor_base + occ_num * OCC_SENSOR_DATA_BLOCK_SIZE);
+}
+
+static inline
+struct occ_sensor_name *get_names_block(struct occ_sensor_data_header *hb)
+{
+	return ((struct occ_sensor_name *)((u64)hb + hb->names_offset));
+}
+
+static inline u32 sensor_handler(int occ_num, int sensor_id, int attr)
+{
+	return sensor_make_handler(SENSOR_OCC, occ_num, sensor_id, attr);
+}
+
+int occ_sensor_read(u32 handle, u32 *data)
+{
+	struct occ_sensor_data_header *hb;
+	struct occ_sensor_name *md;
+	struct occ_sensor_record *sping, *spong;
+	struct occ_sensor_record *sensor;
+	u8 *ping, *pong;
+	u16 id = sensor_get_rid(handle);
+	u8 occ_num = sensor_get_frc(handle);
+	u8 attr = sensor_get_attr(handle);
+
+	if (occ_num > MAX_OCCS)
+		return OPAL_PARAMETER;
+
+	if (attr > MAX_SENSOR_ATTR)
+		return OPAL_PARAMETER;
+
+	hb = get_sensor_header_block(occ_num);
+	md = get_names_block(hb);
+
+	if (hb->valid != 1)
+		return OPAL_HARDWARE;
+
+	if (id > hb->nr_sensors)
+		return OPAL_PARAMETER;
+
+	ping = (u8 *)((u64)hb + hb->reading_ping_offset);
+	pong = (u8 *)((u64)hb + hb->reading_pong_offset);
+	sping = (struct occ_sensor_record *)((u64)ping + md[id].reading_offset);
+	spong = (struct occ_sensor_record *)((u64)pong + md[id].reading_offset);
+
+	/* Check which buffer is valid  and read the data from that.
+	 * Ping Pong	Action
+	 *  0	0	Return with error
+	 *  0	1	Read Pong
+	 *  1	0	Read Ping
+	 *  1	1	Read the buffer with latest timestamp
+	 */
+	if (*ping && *pong) {
+		if (sping->timestamp > spong->timestamp)
+			sensor = sping;
+		else
+			sensor = spong;
+
+	} else if (*ping && !*pong) {
+		sensor = sping;
+	} else if (!*ping && *pong) {
+		sensor = spong;
+	} else if (!*ping && !*pong) {
+		prlog(PR_DEBUG, "OCC: Both ping and pong sensor buffers are invalid\n");
+		return OPAL_HARDWARE;
+	}
+
+	switch (attr) {
+	case SENSOR_SAMPLE:
+		*data = sensor->sample;
+		break;
+	case SENSOR_MAX:
+		*data = sensor->sample_max;
+		break;
+	case SENSOR_MIN:
+		*data = sensor->sample_min;
+		break;
+	default:
+		*data = 0;
+	}
+
+	return OPAL_SUCCESS;
+}
+
+static bool occ_sensor_sanity(struct occ_sensor_data_header *hb, int chipid)
+{
+	if (hb->valid != 0x01) {
+		prerror("OCC: Chip %d sensor data invalid\n", chipid);
+		return false;
+	}
+
+	if (hb->version != 0x01) {
+		prerror("OCC: Chip %d unsupported sensor header block version %d\n",
+			chipid, hb->version);
+		return false;
+	}
+
+	if (hb->reading_version != 0x01) {
+		prerror("OCC: Chip %d unsupported sensor record format %d\n",
+			chipid, hb->reading_version);
+		return false;
+	}
+
+	if (hb->names_version != 0x01) {
+		prerror("OCC: Chip %d unsupported sensor names format %d\n",
+			chipid, hb->names_version);
+		return false;
+	}
+
+	if (hb->name_length != sizeof(struct occ_sensor_name)) {
+		prerror("OCC: Chip %d unsupported sensor names length %d\n",
+			chipid, hb->name_length);
+		return false;
+	}
+
+	if (!hb->nr_sensors) {
+		prerror("OCC: Chip %d has no sensors\n", chipid);
+		return false;
+	}
+
+	if (!hb->names_offset || !hb->reading_ping_offset ||
+	    !hb->reading_pong_offset) {
+		prerror("OCC: Chip %d Invalid sensor buffer pointers\n",
+			chipid);
+		return false;
+	}
+
+	return true;
+}
+
+/*
+ * parse_entity: Parses OCC sensor name to return the entity number like
+ *		 chipid, core-id, dimm-no, gpu-no. 'end' is used to
+ *		 get the subentity strings. Returns -1 if no number is found.
+ *		 TEMPC4 --> returns 4, end will be NULL
+ *		 TEMPGPU2DRAM1 --> returns 2, end = "DRAM1"
+ *		 PWRSYS --> returns -1, end = NULL
+ */
+static int parse_entity(const char *name, char **end)
+{
+	while (*name != '\0') {
+		if (isdigit(*name))
+			break;
+		name++;
+	}
+
+	if (*name)
+		return strtol(name, end, 10);
+	else
+		return -1;
+}
+
+static void add_sensor_label(struct dt_node *node, struct occ_sensor_name *md,
+			     int chipid)
+{
+	char sname[30] = "";
+	char prefix[30] = "";
+	int i;
+
+	if (md->location != OCC_SENSOR_LOC_SYSTEM)
+		snprintf(prefix, sizeof(prefix), "%s %d ", "Chip", chipid);
+
+	for (i = 0; i < ARRAY_SIZE(str_maps); i++)
+		if (!strncmp(str_maps[i].occ_str, md->name,
+			     strlen(str_maps[i].occ_str))) {
+			char *end;
+			int num;
+
+			num = parse_entity(md->name, &end);
+			if (num != -1) {
+				snprintf(sname, sizeof(sname), "%s%s %d %s",
+					 prefix, str_maps[i].opal_str, num,
+					 end);
+			} else {
+				snprintf(sname, sizeof(sname), "%s%s", prefix,
+					 str_maps[i].opal_str);
+			}
+			dt_add_property_string(node, "label", sname);
+			return;
+		}
+
+	/* Fallback to OCC literal if mapping is not found */
+	if (md->location == OCC_SENSOR_LOC_SYSTEM) {
+		dt_add_property_string(node, "label", md->name);
+	} else {
+		snprintf(sname, sizeof(sname), "%s%s", prefix, md->name);
+		dt_add_property_string(node, "label", sname);
+	}
+}
+
+static const char *get_sensor_type_string(enum occ_sensor_type type)
+{
+	switch (type) {
+	case OCC_SENSOR_TYPE_POWER:
+		return "power";
+	case OCC_SENSOR_TYPE_TEMPERATURE:
+		return "temp";
+	case OCC_SENSOR_TYPE_CURRENT:
+		return "curr";
+	case OCC_SENSOR_TYPE_VOLTAGE:
+		return "in";
+	default:
+		break;
+	}
+
+	return "unknown";
+}
+
+static const char *get_sensor_loc_string(enum occ_sensor_location loc)
+{
+	switch (loc) {
+	case OCC_SENSOR_LOC_SYSTEM:
+		return "sys";
+	case OCC_SENSOR_LOC_PROCESSOR:
+		return "proc";
+	case OCC_SENSOR_LOC_MEMORY:
+		return "mem";
+	case OCC_SENSOR_LOC_VRM:
+		return "vrm";
+	case OCC_SENSOR_LOC_CORE:
+		return "core";
+	case OCC_SENSOR_LOC_QUAD:
+		return "quad";
+	case OCC_SENSOR_LOC_GPU:
+		return "gpu";
+	default:
+		break;
+	}
+
+	return "unknown";
+}
+
+void occ_sensors_init(void)
+{
+	struct proc_chip *chip;
+	int occ_num = 0, i;
+
+	/* OCC inband sensors is only supported in P9 */
+	if (proc_gen != proc_gen_p9)
+		return;
+
+	/* Sensors are copied to BAR2 OCC Common Area */
+	chip = next_chip(NULL);
+	if (!chip->occ_common_base) {
+		prerror("OCC: Unassigned OCC Common Area. No sensors found\n");
+		return;
+	}
+
+	occ_sensor_base = chip->occ_common_base + OCC_SENSOR_DATA_BLOCK_OFFSET;
+
+	for_each_chip(chip) {
+		struct occ_sensor_data_header *hb;
+		struct occ_sensor_name *md;
+
+		hb = get_sensor_header_block(occ_num);
+		md = get_names_block(hb);
+
+		/* Sanity check of the Sensor Data Header Block */
+		if (!occ_sensor_sanity(hb, chip->id))
+			continue;
+
+		for (i = 0; i < hb->nr_sensors; i++) {
+			char name[30];
+			const char *type, *loc;
+			struct dt_node *node;
+			u32 handler;
+
+			if (!(md[i].type & HWMON_SENSORS_MASK))
+				continue;
+
+			type = get_sensor_type_string(md[i].type);
+			loc = get_sensor_loc_string(md[i].location);
+			snprintf(name, sizeof(name), "%s-%s", loc, type);
+
+			handler = sensor_handler(occ_num, i, SENSOR_SAMPLE);
+			node = dt_new_addr(sensor_node, name, handler);
+
+			dt_add_property_string(node, "sensor-type", type);
+			dt_add_property_cells(node, "sensor-data", handler);
+
+			handler = sensor_handler(occ_num, i, SENSOR_MAX);
+			dt_add_property_cells(node, "sensor-data-max", handler);
+
+			handler = sensor_handler(occ_num, i, SENSOR_MIN);
+			dt_add_property_cells(node, "sensor-data-min", handler);
+
+			dt_add_property_string(node, "compatible",
+					       "ibm,opal-sensor");
+			dt_add_property_string(node, "occ_label", md[i].name);
+			add_sensor_label(node, &md[i], chip->id);
+		}
+		occ_num++;
+	}
+}
diff --git a/include/sensor.h b/include/sensor.h
index 7eb3fa5..445a6bc 100644
--- a/include/sensor.h
+++ b/include/sensor.h
@@ -53,6 +53,7 @@ 
  */
 enum {
 	SENSOR_FSP = 0,
+	SENSOR_OCC = 6,
 	SENSOR_DTS = 7,
 };
 
diff --git a/include/skiboot.h b/include/skiboot.h
index 1a153b0..db4ca36 100644
--- a/include/skiboot.h
+++ b/include/skiboot.h
@@ -310,4 +310,8 @@  extern int fake_nvram_info(uint32_t *total_size);
 extern int fake_nvram_start_read(void *dst, uint32_t src, uint32_t len);
 extern int fake_nvram_write(uint32_t offset, void *src, uint32_t size);
 
+/* OCC Inband Sensors */
+extern void occ_sensors_init(void);
+extern int occ_sensor_read(u32 handle, u32 *data);
+
 #endif /* __SKIBOOT_H */