[Mellanox] Support new platform API get_port_or_cage_type for RJ45 ports (#11336)

- Why I did it
Support get_port_or_cage_type for RJ45 ports

- How I did it
Implement the new platform API get_port_or_cage_type
Fix the issue: unable to import SFP when chassis object is destructed

- How to verify it
Manually test and regression test

Signed-off-by: Stephen Sun <stephens@nvidia.com>

platform/mellanox/mlnx-platform-api/sonic_platform/chassis.py

@@ -30,7 +30,6 @@ try:
     from .utils import extract_RJ45_ports_index
     from . import utils
     from .device_data import DeviceDataManager
-    from .sfp import SFP, RJ45Port, deinitialize_sdk_handle
 except ImportError as e:
     raise ImportError (str(e) + "- required module not found")
 
@@ -110,6 +109,8 @@ class Chassis(ChassisBase):
         self.sfp_event = None
         self.reboot_cause_initialized = False
 
+        self.sfp_module = None
+
         # Build the RJ45 port list from platform.json and hwsku.json
         self.RJ45_port_list = extract_RJ45_ports_index()
 
@@ -120,9 +121,8 @@ class Chassis(ChassisBase):
             self.sfp_event.deinitialize()
 
         if self._sfp_list:
-            from .sfp import SFP, deinitialize_sdk_handle
-            if SFP.shared_sdk_handle:
-                deinitialize_sdk_handle(SFP.shared_sdk_handle)
+            if self.sfp_module.SFP.shared_sdk_handle:
+                self.sfp_module.deinitialize_sdk_handle(sfp_module.SFP.shared_sdk_handle)
 
     ##############################################
     # PSU methods
@@ -241,6 +241,12 @@ class Chassis(ChassisBase):
     # SFP methods
     ##############################################
 
+    def _import_sfp_module(self):
+        if not self.sfp_module:
+            from . import sfp as sfp_module
+            self.sfp_module = sfp_module
+        return self.sfp_module
+
     def initialize_single_sfp(self, index):
         sfp_count = self.get_num_sfps()
         if index < sfp_count:
@@ -248,32 +254,32 @@ class Chassis(ChassisBase):
                 self._sfp_list = [None] * sfp_count
 
             if not self._sfp_list[index]:
-                from .sfp import SFP
+                sfp_module = self._import_sfp_module()
                 if self.RJ45_port_list and index in self.RJ45_port_list:
-                    self._sfp_list[index] = RJ45Port(index)
+                    self._sfp_list[index] = sfp_module.RJ45Port(index)
                 else:
-                    self._sfp_list[index] = SFP(index)
+                    self._sfp_list[index] = sfp_module.SFP(index)
                 self.sfp_initialized_count += 1
 
     def initialize_sfp(self):
         if not self._sfp_list:
-            from .sfp import SFP
+            sfp_module = self._import_sfp_module()
             sfp_count = self.get_num_sfps()
             for index in range(sfp_count):
                 if self.RJ45_port_list and index in self.RJ45_port_list:
-                    sfp_module = RJ45Port(index)
+                    sfp_object = sfp_module.RJ45Port(index)
                 else:
-                    sfp_module = SFP(index)
-                self._sfp_list.append(sfp_module)
+                    sfp_object = sfp_module.SFP(index)
+                self._sfp_list.append(sfp_object)
             self.sfp_initialized_count = sfp_count
         elif self.sfp_initialized_count != len(self._sfp_list):
-            from .sfp import SFP
+            sfp_module = self._import_sfp_module()
             for index in range(len(self._sfp_list)):
                 if self._sfp_list[index] is None:
                     if self.RJ45_port_list and index in self.RJ45_port_list:
-                        self._sfp_list[index] = RJ45Port(index)
+                        self._sfp_list[index] = sfp_module.RJ45Port(index)
                     else:
-                        self._sfp_list[index] = SFP(index)
+                        self._sfp_list[index] = sfp_module.SFP(index)
             self.sfp_initialized_count = len(self._sfp_list)
 
     def get_num_sfps(self):
@@ -313,6 +319,30 @@ class Chassis(ChassisBase):
         self.initialize_single_sfp(index)
         return super(Chassis, self).get_sfp(index)
 
+    def get_port_or_cage_type(self, index):
+        """
+        Retrieves sfp port or cage type corresponding to physical port <index>
+
+        Args:
+            index: An integer (>=0), the index of the sfp to retrieve.
+                   The index should correspond to the physical port in a chassis.
+                   For example:-
+                   1 for Ethernet0, 2 for Ethernet4 and so on for one platform.
+                   0 for Ethernet0, 1 for Ethernet4 and so on for another platform.
+
+        Returns:
+            The masks of all types of port or cage that can be supported on the port
+            Types are defined in sfp_base.py
+            Eg.
+                Both SFP and SFP+ are supported on the port, the return value should be 0x0a
+                which is 0x02 | 0x08
+        """
+        index = index - 1
+        if self.RJ45_port_list and index in self.RJ45_port_list:
+            from sonic_platform_base.sfp_base import SfpBase
+            return SfpBase.SFP_PORT_TYPE_BIT_RJ45
+        raise NotImplementedError
+
     def get_change_event(self, timeout=0):
         """
         Returns a nested dictionary containing all devices which have

platform/mellanox/mlnx-platform-api/tests/test_chassis.py

@@ -29,6 +29,7 @@ modules_path = os.path.dirname(test_path)
 sys.path.insert(0, modules_path)
 
 import sonic_platform.chassis
+from sonic_platform_base.sfp_base import SfpBase
 from sonic_platform.chassis import Chassis
 from sonic_platform.device_data import DeviceDataManager
 
@@ -282,3 +283,16 @@ class TestChassis:
         sonic_platform.chassis.DMI_FILE = old_dmi_file
         os.system("rm -f " + new_dmi_file)
         assert rev == "N/A"
+
+    def test_get_port_or_cage_type(self):
+        chassis = Chassis()
+        chassis.RJ45_port_list = [0]
+        assert SfpBase.SFP_PORT_TYPE_BIT_RJ45 == chassis.get_port_or_cage_type(1)
+
+        exceptionRaised = False
+        try:
+            chassis.get_port_or_cage_type(2)
+        except NotImplementedError:
+            exceptionRaised = True
+
+        assert exceptionRaised