[201911] DellEMC: S6000, S6100 - Enable thermalctld, Platform API changes (#9384)

Why I did it
To incorporate the below changes in DellEMC S6100, S6000 platforms.

Enable thermalctld
Backport Platform API changes from master branch.
How I did it
Remove 'skip_thermalctld:true' in pmon_daemon_control.json
Implement the platform API methods in the respective device files
How to verify it
Verified that platform data is displayed by show platform fan and show platform temperature commands.

device/dell/x86_64-dell_s6000_s1220-r0/pmon_daemon_control.json

@@ -1,4 +1,3 @@
 {
-    "skip_ledd": true,
+    "skip_ledd": true
-    "skip_thermalctld": true
 }

device/dell/x86_64-dell_s6100_c2538-r0/pmon_daemon_control.json

@@ -1,4 +1,3 @@
 {
-    "skip_ledd": true,
+    "skip_ledd": true
-    "skip_thermalctld": true
 }

platform/broadcom/sonic-platform-modules-dell/s6000/sonic_platform/chassis.py

@@ -10,21 +10,21 @@
 try:
     import os
     import time
-    import datetime
-    import struct
     import subprocess
+    import struct
     from sonic_platform_base.chassis_base import ChassisBase
-    from sonic_platform.sfp import Sfp
+    from sonic_platform.component import Component
     from sonic_platform.eeprom import Eeprom, EepromS6000
     from sonic_platform.fan import Fan
     from sonic_platform.psu import Psu
+    from sonic_platform.sfp import Sfp
     from sonic_platform.thermal import Thermal
-    from sonic_platform.component import Component
 except ImportError as e:
     raise ImportError(str(e) + "- required module not found")
 
 
-MAX_S6000_FAN = 3
+MAX_S6000_FANTRAY = 3
+MAX_S6000_FAN_PER_FANTRAY = 2
 MAX_S6000_PSU = 2
 MAX_S6000_THERMAL = 10
 MAX_S6000_COMPONENT = 4
@@ -76,9 +76,10 @@ class Chassis(ChassisBase):
         else:
             self._eeprom = EepromS6000()
 
-        for i in range(MAX_S6000_FAN):
+        for i in range(1, MAX_S6000_FANTRAY+1):
-            fan = Fan(i)
+            for j in range(1, MAX_S6000_FAN_PER_FANTRAY+1):
-            self._fan_list.append(fan)
+                fan = Fan(fantray_index=i, fan_index=j)
+                self._fan_list.append(fan)
 
         for i in range(MAX_S6000_PSU):
             psu = Psu(i)
@@ -102,7 +103,7 @@ class Chassis(ChassisBase):
         try:
             with open(mb_reg_file, 'r') as fd:
                 rv = fd.read()
-        except Exception as error:
+        except IOError:
             rv = 'ERR'
 
         rv = rv.rstrip('\r\n')

platform/broadcom/sonic-platform-modules-dell/s6000/sonic_platform/eeprom.py

@@ -18,7 +18,6 @@
 
 try:
     import binascii
-    import os
     import redis
     import struct
     from collections import OrderedDict
@@ -37,8 +36,8 @@ psu_eeprom_format = [
     ('Fab Rev', 's', 2)
     ]
 
-# Fan eeprom fields in format required by EepromDecoder
+# FanTray eeprom fields in format required by EepromDecoder
-fan_eeprom_format = [
+fantray_eeprom_format = [
     ('PPID', 's', 20), ('DPN Rev', 's', 3), ('Service Tag', 's', 7),
     ('Part Number', 's', 10), ('Part Num Revision', 's', 3),
     ('Mfg Test', 's', 2), ('Redundant copy', 's', 83),
@@ -52,10 +51,10 @@ class Eeprom(TlvInfoDecoder):
 
     I2C_DIR = "/sys/class/i2c-adapter/"
 
-    def __init__(self, is_psu=False, psu_index=0, is_fan=False, fan_index=0):
+    def __init__(self, is_psu=False, psu_index=0, is_fantray=False, fantray_index=0):
         self.is_psu_eeprom = is_psu
-        self.is_fan_eeprom = is_fan
+        self.is_fantray_eeprom = is_fantray
-        self.is_sys_eeprom = not (is_psu | is_fan)
+        self.is_sys_eeprom = not (is_psu | is_fantray)
 
         if self.is_sys_eeprom:
             self.start_offset = 0
@@ -72,10 +71,10 @@ class Eeprom(TlvInfoDecoder):
                     + "i2c-1/1-005{}/eeprom".format(2 - self.index)
                 self.format = psu_eeprom_format
             else:
-                self.index = fan_index
+                self.index = fantray_index
                 self.eeprom_path = self.I2C_DIR \
                     + "i2c-11/11-005{}/eeprom".format(4 - self.index)
-                self.format = fan_eeprom_format
+                self.format = fantray_eeprom_format
             EepromDecoder.__init__(self, self.eeprom_path, self.format,
                                    self.start_offset, '', True)
             self._load_device_eeprom()

platform/broadcom/sonic-platform-modules-dell/s6000/sonic_platform/fan.py

@@ -27,31 +27,40 @@ class Fan(FanBase):
 
     CPLD_DIR = "/sys/devices/platform/dell-s6000-cpld.0/"
     I2C_DIR = "/sys/class/i2c-adapter/"
+    FAN_DEV_MAPPING = {
+        1: {1: ("i2c-11/11-002a", 1), 2: ("i2c-11/11-002a", 2)},
+        2: {1: ("i2c-11/11-0029", 3), 2: ("i2c-11/11-0029", 4)},
+        3: {1: ("i2c-11/11-0029", 1), 2: ("i2c-11/11-0029", 2)}
+    }
 
-    def __init__(self, fan_index, psu_fan=False, dependency=None):
+    def __init__(self, fantray_index=1, fan_index=1,
+                 psu_index=1, psu_fan=False, dependency=None):
         self.is_psu_fan = psu_fan
         self.is_driver_initialized = True
 
         if not self.is_psu_fan:
             # Fan is 1-based in DellEMC platforms
-            self.index = fan_index + 1
+            self.fantray_index = fantray_index
-            self.fan_presence_reg = "fan_prs"
-            self.fan_led_reg = "fan{}_led".format(fan_index)
-            self.get_fan_speed_reg = self.I2C_DIR + "i2c-11/11-0029/" +\
-                    "fan{}_input".format(self.index)
-            self.set_fan_speed_reg = self.I2C_DIR + "i2c-11/11-0029/" +\
-                    "fan{}_target".format(self.index)
-            self.eeprom = Eeprom(is_fan=True, fan_index=self.index)
-            self.max_fan_speed = MAX_S6000_FAN_SPEED
-            self.supported_led_color = ['off', 'green', 'amber']
-        else:
             self.index = fan_index
+
+            self.fan_presence_reg = "fan_prs"
+            self.get_fan_speed_reg = self.I2C_DIR +\
+                    "{}/fan{}_input".format(*self.FAN_DEV_MAPPING[fantray_index][fan_index])
+            self.set_fan_speed_reg = self.I2C_DIR +\
+                    "{}/fan{}_target".format(*self.FAN_DEV_MAPPING[fantray_index][fan_index])
+            self.max_fan_speed = MAX_S6000_FAN_SPEED
+
+            # FanTray EEPROM
+            self.eeprom = Eeprom(is_fantray=True, fantray_index=self.fantray_index)
+        else:
+            self.psu_index = psu_index
+            self.index = 1
             self.dependency = dependency
             self.set_fan_speed_reg = self.I2C_DIR +\
-                    "i2c-1/1-005{}/fan1_target".format(10 - self.index)
+                    "i2c-1/1-005{}/fan1_target".format(10 - self.psu_index)
 
             hwmon_dir = self.I2C_DIR +\
-                    "i2c-1/1-005{}/hwmon/".format(10 - self.index)
+                    "i2c-1/1-005{}/hwmon/".format(10 - self.psu_index)
             try:
                 hwmon_node = os.listdir(hwmon_dir)[0]
             except OSError:
@@ -73,31 +82,13 @@ class Fan(FanBase):
         try:
            with open(cpld_reg_file, 'r') as fd:
                 rv = fd.read()
-        except:
+        except IOError:
             rv = 'ERR'
 
         rv = rv.rstrip('\r\n')
         rv = rv.lstrip(" ")
         return rv
 
-    def _set_cpld_register(self, reg_name, value):
-        # On successful write, returns the value will be written on
-        # reg_name and on failure returns 'ERR'
-        rv = 'ERR'
-        cpld_reg_file = self.CPLD_DIR + reg_name
-
-        if (not os.path.isfile(cpld_reg_file)):
-            print "open error"
-            return rv
-
-        try:
-           with open(cpld_reg_file, 'w') as fd:
-                rv = fd.write(str(value))
-        except:
-            rv = 'ERR'
-
-        return rv
-
     def _get_i2c_register(self, reg_file):
         # On successful read, returns the value read from given
         # reg_name and on failure returns 'ERR'
@@ -117,7 +108,7 @@ class Fan(FanBase):
         try:
             with open(reg_file, 'r') as fd:
                 rv = fd.read()
-        except:
+        except IOError:
             rv = 'ERR'
 
         rv = rv.rstrip('\r\n')
@@ -135,7 +126,7 @@ class Fan(FanBase):
         try:
             with open(reg_file, 'w') as fd:
                 rv = fd.write(str(value))
-        except:
+        except IOError:
             rv = 'ERR'
 
         return rv
@@ -155,9 +146,9 @@ class Fan(FanBase):
             string: The name of the Fan
         """
         if not self.is_psu_fan:
-            return "Fan{}".format(self.index)
+            return "FanTray{}-Fan{}".format(self.fantray_index, self.index)
         else:
-            return "PSU{} Fan".format(self.index)
+            return "PSU{} Fan".format(self.psu_index)
 
     def get_presence(self):
         """
@@ -185,10 +176,7 @@ class Fan(FanBase):
         Returns:
             string: Part number of Fan
         """
-        if not self.is_psu_fan:
+        return 'NA'
-            return self.eeprom.get_part_number()
-        else:
-            return 'NA'
 
     def get_serial(self):
         """
@@ -197,11 +185,7 @@ class Fan(FanBase):
         Returns:
             string: Serial number of Fan
         """
-        # Sample Serial number format "US-01234D-54321-25A-0123-A00"
+        return 'NA'
-        if not self.is_psu_fan:
-            return self.eeprom.get_serial_number()
-        else:
-            return 'NA'
 
     def get_status(self):
         """
@@ -213,7 +197,7 @@ class Fan(FanBase):
         status = False
         fan_speed = self._get_i2c_register(self.get_fan_speed_reg)
         if (fan_speed != 'ERR'):
-            if (int(fan_speed) > 14000):
+            if (int(fan_speed) > 1000):
                 status = True
 
         return status
@@ -298,16 +282,9 @@ class Fan(FanBase):
         Returns:
             bool: True if set success, False if fail.
         """
-        if self.is_psu_fan or (color not in self.supported_led_color):
+        # No LED available for FanTray and PSU Fan
-            return False
+        # Return True to avoid thermalctld alarm.
-        if(color == self.STATUS_LED_COLOR_AMBER):
+        return True
-            color = 'yellow'
-
-        rv = self._set_cpld_register(self.fan_led_reg ,color)
-        if (rv != 'ERR'):
-            return True
-        else:
-            return False
 
     def get_status_led(self):
         """
@@ -316,18 +293,8 @@ class Fan(FanBase):
         Returns:
             A string, one of the predefined STATUS_LED_COLOR_* strings.
         """
-        if self.is_psu_fan:
+        # No LED available for FanTray and PSU Fan
-            # No LED available for PSU Fan
+        return None
-            return None
-
-        fan_led = self._get_cpld_register(self.fan_led_reg)
-        if (fan_led != 'ERR'):
-            if (fan_led == 'yellow'):
-                return self.STATUS_LED_COLOR_AMBER
-            else:
-                return fan_led
-        else:
-            return self.STATUS_LED_COLOR_OFF
 
     def get_target_speed(self):
         """
@@ -337,4 +304,5 @@ class Fan(FanBase):
             An integer, the percentage of full fan speed, in the range 0
             (off) to 100 (full speed)
         """
-        return 79
+        # Fan speeds are controlled by fancontrol.sh
+        return self.get_speed()

platform/broadcom/sonic-platform-modules-dell/s6000/sonic_platform/psu.py

@@ -26,6 +26,7 @@ class Psu(PsuBase):
     I2C_DIR = "/sys/class/i2c-adapter/"
 
     def __init__(self, psu_index):
+        PsuBase.__init__(self)
         # PSU is 1-based in DellEMC platforms
         self.index = psu_index + 1
         self.psu_presence_reg = "psu{}_prs".format(psu_index)
@@ -52,11 +53,7 @@ class Psu(PsuBase):
 
         self.eeprom = Eeprom(is_psu=True, psu_index=self.index)
 
-        # Overriding _fan_list class variable defined in PsuBase, to
+        self._fan_list.append(Fan(psu_index=self.index, psu_fan=True, dependency=self))
-        # make it unique per Psu object
-        self._fan_list = []
-
-        self._fan_list.append(Fan(self.index, psu_fan=True, dependency=self))
 
     def _get_cpld_register(self, reg_name):
         # On successful read, returns the value read from given
@@ -109,9 +106,9 @@ class Psu(PsuBase):
         power_reg = glob.glob(self.psu_power_reg)
 
         if len(voltage_reg) and len(current_reg) and len(power_reg):
-            self.psu_voltage_reg = voltage_reg_path[0]
+            self.psu_voltage_reg = voltage_reg[0]
-            self.psu_current_reg = current_reg_path[0]
+            self.psu_current_reg = current_reg[0]
-            self.psu_power_reg = power_reg_path[0]
+            self.psu_power_reg = power_reg[0]
             self.is_driver_initialized = True
 
     def get_name(self):

platform/broadcom/sonic-platform-modules-dell/s6000/sonic_platform/thermal.py

@@ -96,7 +96,7 @@ class Thermal(ThermalBase):
         try:
             with open(sysfs_file, 'r') as fd:
                 rv = fd.read()
-        except:
+        except IOError:
             rv = 'ERR'
 
         rv = rv.rstrip('\r\n')

platform/broadcom/sonic-platform-modules-dell/s6100/sonic_platform/chassis.py

@@ -10,17 +10,15 @@
 
 try:
     import os
-    from sonic_platform_base.platform_base import PlatformBase
+    import time
     from sonic_platform_base.chassis_base import ChassisBase
-    from sonic_platform.sfp import Sfp
+    from sonic_platform.component import Component
-    from sonic_platform.psu import Psu
+    from sonic_platform.eeprom import Eeprom
     from sonic_platform.fan import Fan
     from sonic_platform.module import Module
+    from sonic_platform.psu import Psu
     from sonic_platform.thermal import Thermal
-    from sonic_platform.component import Component
     from sonic_platform.watchdog import Watchdog
-    from eeprom import Eeprom
-    import time
 except ImportError as e:
     raise ImportError(str(e) + "- required module not found")
 
@@ -65,7 +63,7 @@ class Chassis(ChassisBase):
             self._module_list.append(module)
             self._sfp_list.extend(module._sfp_list)
 
-        for i in range(MAX_S6100_FAN):
+        for i in range(1, MAX_S6100_FAN+1):
             fan = Fan(i)
             self._fan_list.append(fan)
 

platform/broadcom/sonic-platform-modules-dell/s6100/sonic_platform/eeprom.py

@@ -73,6 +73,10 @@ class Eeprom(eeprom_tlvinfo.TlvInfoDecoder):
 
                 tlv_index += ord(eeprom[tlv_index+1]) + 2
 
+            if self.is_module:
+                # In S6100, individual modules doesn't have MAC address
+                mac_code = "0x%02X" % self._TLV_CODE_MAC_BASE
+                self.eeprom_tlv_dict[mac_code] = '00:00:00:00:00:00'
 
     def serial_number_str(self):
         (is_valid, results) = self.get_tlv_field(

platform/broadcom/sonic-platform-modules-dell/s6100/sonic_platform/fan.py

@@ -26,13 +26,10 @@ class Fan(FanBase):
     HWMON_NODE = os.listdir(HWMON_DIR)[0]
     MAILBOX_DIR = HWMON_DIR + HWMON_NODE
 
-    def __init__(self, fantray_index=1, fan_index=1, psu_fan=False):
+    def __init__(self, fantray_index=1, psu_index=1, psu_fan=False):
         self.is_psu_fan = psu_fan
         if not self.is_psu_fan:
-            # API index is starting from 0, DellEMC platform index is starting
+            self.fantrayindex = fantray_index
-            # from 1
-            self.fantrayindex = fantray_index + 1
-            self.fanindex = fan_index + 1
             self.fan_presence_reg = "fan{}_fault".format(
                         2 * self.fantrayindex - 1)
             self.fan_status_reg = "fan{}_alarm".format(
@@ -41,15 +38,12 @@ class Fan(FanBase):
                         2 * self.fantrayindex - 1)
             self.get_fan_dir_reg = "fan{}_airflow".format(
                         2 * self.fantrayindex - 1)
-            self.fan_serialno_reg = "fan{}_serialno".format(
-                        2 * self.fantrayindex - 1)
             self.max_fan_speed = MAX_S6100_FAN_SPEED
         else:
-            # PSU Fan index starts from 11
+            self.psuindex = psu_index
-            self.fanindex = fan_index + 10
+            self.fan_presence_reg = "fan{}_fault".format(self.psuindex + 10)
-            self.fan_presence_reg = "fan{}_fault".format(self.fanindex)
+            self.get_fan_speed_reg = "fan{}_input".format(self.psuindex + 10)
-            self.get_fan_speed_reg = "fan{}_input".format(self.fanindex)
+            self.get_fan_dir_reg = "fan{}_airflow".format(self.psuindex + 10)
-            self.get_fan_dir_reg = "fan{}_airflow".format(self.fanindex)
             self.max_fan_speed = MAX_S6100_PSU_FAN_SPEED
 
     def _get_pmc_register(self, reg_name):
@@ -77,10 +71,9 @@ class Fan(FanBase):
             string: The name of the device
         """
         if not self.is_psu_fan:
-            return "FanTray{}-Fan{}".format(
+            return "FanTray{}-Fan1".format(self.fantrayindex)
-                                self.fantrayindex, self.fanindex - 1)
         else:
-            return "PSU{} Fan".format(self.fanindex - 10)
+            return "PSU{} Fan".format(self.psuindex)
 
     def get_model(self):
         """
@@ -88,21 +81,7 @@ class Fan(FanBase):
         Returns:
             string: Part number of FAN
         """
-        # For Serial number "US-01234D-54321-25A-0123-A00", the part
+        return 'NA'
-        # number is "01234D"
-        if self.is_psu_fan:
-            return 'NA'
-
-        fan_serialno = self._get_pmc_register(self.fan_serialno_reg)
-        if (fan_serialno != 'ERR') and self.get_presence():
-            if (len(fan_serialno.split('-')) > 1):
-                fan_partno = fan_serialno.split('-')[1]
-            else:
-                fan_partno = 'NA'
-        else:
-            fan_partno = 'NA'
-
-        return fan_partno
 
     def get_serial(self):
         """
@@ -110,15 +89,7 @@ class Fan(FanBase):
         Returns:
             string: Serial number of FAN
         """
-        # Sample Serial number format "US-01234D-54321-25A-0123-A00"
+        return 'NA'
-        if self.is_psu_fan:
-            return 'NA'
-
-        fan_serialno = self._get_pmc_register(self.fan_serialno_reg)
-        if (fan_serialno == 'ERR') or not self.get_presence():
-            fan_serialno = 'NA'
-
-        return fan_serialno
 
     def get_presence(self):
         """
@@ -126,14 +97,14 @@ class Fan(FanBase):
         Returns:
             bool: True if fan is present, False if not
         """
-        status = False
+        presence = False
-        fantray_presence = self._get_pmc_register(self.fan_presence_reg)
+        fan_presence = self._get_pmc_register(self.fan_presence_reg)
-        if (fantray_presence != 'ERR'):
+        if (fan_presence != 'ERR'):
-            fantray_presence = int(fantray_presence, 10)
+            fan_presence = int(fan_presence, 10)
-            if (~fantray_presence & 0b1):
+            if (~fan_presence & 0b1):
-                status = True
+                presence = True
 
-        return status
+        return presence
 
     def get_status(self):
         """
@@ -216,7 +187,6 @@ class Fan(FanBase):
         Returns:
             bool: True if set success, False if fail.
         """
-
         # Fan speeds are controlled by Smart-fussion FPGA.
         return False
 
@@ -229,9 +199,9 @@ class Fan(FanBase):
         Returns:
             bool: True if set success, False if fail.
         """
-        # Leds are controlled by Smart-fussion FPGA.
+        # No LED available for FanTray and PSU Fan
-        status = False
+        # Return True to avoid thermalctld alarm.
-        return status
+        return True
 
     def get_status_led(self):
         """
@@ -240,17 +210,8 @@ class Fan(FanBase):
         Returns:
             A string, one of the predefined STATUS_LED_COLOR_* strings.
         """
-        if self.is_psu_fan:
+        # No LED available for FanTray and PSU Fan
-            # No LED available for PSU Fan
+        return None
-            return None
-        else:
-            if self.get_presence():
-                if self.get_status():
-                    return self.STATUS_LED_COLOR_GREEN
-                else:
-                    return self.STATUS_LED_COLOR_AMBER
-            else:
-                return self.STATUS_LED_COLOR_OFF
 
     def get_target_speed(self):
         """
@@ -259,6 +220,6 @@ class Fan(FanBase):
             An integer, the percentage of full fan speed, in the range 0 (off)
                  to 100 (full speed)
         """
-        return  0
+        # Fan speeds are controlled by Smart-fussion FPGA.
-
+        # Return current speed to avoid false thermalctld alarm.
-
+        return self.get_speed()

platform/broadcom/sonic-platform-modules-dell/s6100/sonic_platform/module.py

@@ -51,6 +51,7 @@ class Module(ModuleBase):
       }
 
     def __init__(self, module_index):
+        ModuleBase.__init__(self)
         # Modules are 1-based in DellEMC platforms
         self.index = module_index + 1
         self.port_start = (self.index - 1) * 16
@@ -61,11 +62,6 @@ class Module(ModuleBase):
         self.iom_status_reg = "iom_status"
         self.iom_presence_reg = "iom_presence"
 
-        # Overriding _component_list and _sfp_list class variables defined in
-        # ModuleBase, to make them unique per Module object
-        self._component_list = []
-        self._sfp_list = []
-
         component = Component(is_module=True, iom_index=self.index,
                               i2c_line=self.port_i2c_line)
         self._component_list.append(component)

platform/broadcom/sonic-platform-modules-dell/s6100/sonic_platform/psu.py

@@ -25,6 +25,7 @@ class Psu(PsuBase):
     MAILBOX_DIR = HWMON_DIR + HWMON_NODE
 
     def __init__(self, psu_index):
+        PsuBase.__init__(self)
         # PSU is 1-based in DellEMC platforms
         self.index = psu_index + 1
         self.psu_presence_reg = "psu{}_presence".format(self.index)
@@ -38,12 +39,8 @@ class Psu(PsuBase):
             self.psu_current_reg = "curr702_input"
             self.psu_power_reg = "power4_input"
 
-        # Overriding _fan_list class variable defined in PsuBase, to
-        # make it unique per Psu object
-        self._fan_list = []
-
         # Passing True to specify it is a PSU fan
-        psu_fan = Fan(fan_index=self.index, psu_fan=True)
+        psu_fan = Fan(psu_index=self.index, psu_fan=True)
         self._fan_list.append(psu_fan)
 
     def _get_pmc_register(self, reg_name):

platform/broadcom/sonic-platform-modules-dell/s6100/sonic_platform/thermal.py

@@ -49,10 +49,14 @@ class Thermal(ThermalBase):
         self.thermal_temperature_file = self.HWMON_DIR \
             + "temp{}_input".format(hwmon_temp_index)
         self.thermal_high_threshold_file = self.HWMON_DIR \
-            + "temp{}_crit".format(hwmon_temp_index)
+            + "temp{}_max".format(hwmon_temp_index)
         self.thermal_low_threshold_file = self.HWMON_DIR \
             + "temp{}_min".format(hwmon_temp_index)
 
+        if not self.is_cpu_thermal:
+            self.thermal_high_crit_threshold_file = self.HWMON_DIR \
+                + "temp{}_crit".format(hwmon_temp_index)
+
     def _read_sysfs_file(self, sysfs_file):
         # On successful read, returns the value read from given
         # sysfs_file and on failure returns 'ERR'
@@ -180,6 +184,27 @@ class Thermal(ThermalBase):
 
         return thermal_low_threshold / 1000.0
 
+    def get_high_critical_threshold(self):
+        """
+        Retrieves the high critical threshold temperature of thermal
+
+        Returns:
+            A float number, the high critical threshold temperature of
+            thermal in Celsius up to nearest thousandth of one degree
+            Celsius, e.g. 30.125
+        """
+        if self.is_cpu_thermal:
+            return super(Thermal, self).get_high_critical_threshold()
+
+        thermal_high_crit_threshold = self._read_sysfs_file(
+            self.thermal_high_crit_threshold_file)
+        if (thermal_high_crit_threshold != 'ERR'):
+            thermal_high_crit_threshold = float(thermal_high_crit_threshold)
+        else:
+            thermal_high_crit_threshold = 0
+
+        return thermal_high_crit_threshold / 1000.0
+
     def set_high_threshold(self, temperature):
         """
         Sets the high threshold temperature of thermal