Restore optoe page to default 0 for active cables

sonic_platform_base/sonic_xcvr/sfp_optoe_base.py

@@ -7,6 +7,10 @@
 
 from ..sfp_base import SfpBase
 
+SFP_OPTOE_PAGE_SELECT_OFFSET = 127
+SFP_OPTOE_UPPER_PAGE0_OFFSET = 128
+SFP_OPTOE_PAGE_SIZE = 128
+
 class SfpOptoeBase(SfpBase):
     def __init__(self):
         SfpBase.__init__(self)
@@ -261,6 +265,12 @@ def set_optoe_write_max(self, write_max):
         except (OSError, IOError):
             pass
 
+    def get_optoe_current_page(self):
+        return self.read_eeprom(SFP_OPTOE_PAGE_SELECT_OFFSET, 1)[0]
+
+    def set_page0(self):
+        self.write_eeprom(SFP_OPTOE_PAGE_SELECT_OFFSET, 1, bytearray([0x00]))
+
     def set_optoe_write_timeout(self, write_timeout):
         sys_path = self.get_eeprom_path()
         sys_path = sys_path.replace("eeprom", "write_timeout")
@@ -273,6 +283,12 @@ def set_optoe_write_timeout(self, write_timeout):
     def read_eeprom(self, offset, num_bytes):
         try:
             with open(self.get_eeprom_path(), mode='rb', buffering=0) as f:
+                if offset >= SFP_OPTOE_UPPER_PAGE0_OFFSET  and \
+                    offset < (SFP_OPTOE_UPPER_PAGE0_OFFSET+SFP_OPTOE_PAGE_SIZE) and \
+                        self.get_optoe_current_page() != 0:
+                    # Restoring the page to 0 helps in cases where the optoe driver failed to restore
+                    # the page when say the module was busy with CDB command processing
+                   self.set_page0()
                 f.seek(offset)
                 return bytearray(f.read(num_bytes))
         except (OSError, IOError):

tests/sonic_xcvr/test_sfp_optoe_base.py

@@ -2,7 +2,7 @@
 from mock import MagicMock 
 from mock import patch 
 import pytest 
-from sonic_platform_base.sonic_xcvr.sfp_optoe_base import SfpOptoeBase 
+from sonic_platform_base.sonic_xcvr.sfp_optoe_base import SfpOptoeBase, SFP_OPTOE_UPPER_PAGE0_OFFSET, SFP_OPTOE_PAGE_SELECT_OFFSET
 from sonic_platform_base.sonic_xcvr.api.public.c_cmis import CCmisApi
 from sonic_platform_base.sonic_xcvr.api.public.cmis import CmisApi
 from sonic_platform_base.sonic_xcvr.mem_maps.public.c_cmis import CCmisMemMap 
@@ -132,3 +132,13 @@ def test_set_power(self):
             exception_raised = True
         assert exception_raised
 
+    def test_default_page(self):
+        with patch("builtins.open", mock_open(read_data=b'\x01')) as mocked_file:
+            self.sfp_optoe_api.write_eeprom =  MagicMock(return_value=True)
+            self.sfp_optoe_api.get_optoe_current_page = MagicMock(return_value=0x10)
+            self.sfp_optoe_api.get_eeprom_path = MagicMock(return_value='/sys/class/eeprom')
+            data = self.sfp_optoe_api.read_eeprom(SFP_OPTOE_UPPER_PAGE0_OFFSET, 1)
+            mocked_file.assert_called_once_with("/sys/class/eeprom", mode='rb', buffering=0)
+            assert data == b'\x01'
+            self.sfp_optoe_api.write_eeprom.assert_called_once_with(SFP_OPTOE_PAGE_SELECT_OFFSET, 1, b'\x00')
+            self.sfp_optoe_api.get_optoe_current_page.assert_called_once()