[Mellanox][pcied] Ignore bus on pcie.yaml for Mellanox switches

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

@@ -0,0 +1,69 @@
+########################################################################
+#
+# Copyright (C) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+#
+# Module contains a platform specific implementation of SONiC Platform
+# Base PCIe class
+#
+########################################################################
+import os
+import re
+
+try:
+    from sonic_platform_base.sonic_pcie.pcie_common import PcieUtil
+except ImportError as e:
+    raise ImportError(str(e) + "- required module not found")
+
+SYSFS_PCI_DEVICE_PATH = '/sys/bus/pci/devices/'
+
+
+class Pcie(PcieUtil):
+    # check the current PCIe device with config file and return the result
+    # use bus from _device_id_to_bus_map instead of from yaml file
+    def get_pcie_check(self):
+        self.load_config_file()
+        for item_conf in self.confInfo:
+            id_conf = item_conf["id"]
+            dev_conf = item_conf["dev"]
+            fn_conf = item_conf["fn"]
+            bus_conf = self._device_id_to_bus_map.get(id_conf)
+            if bus_conf and self.check_pcie_sysfs(bus=int(bus_conf, base=16), device=int(dev_conf, base=16),
+                                                  func=int(fn_conf, base=16)):
+                item_conf["result"] = "Passed"
+            else:
+                item_conf["result"] = "Failed"
+        return self.confInfo
+
+    # Create
+    def _create_device_id_to_bus_map(self):
+        self._device_id_to_bus_map = {}
+        self.load_config_file()
+        device_folders = os.listdir(SYSFS_PCI_DEVICE_PATH)
+        for folder in device_folders:
+            # For each folder in the sysfs tree we check if it matches the normal PCIe device folder pattern,
+            # If match we add the device id from the device file and the bus from the folder name to the map
+            #
+            # Example for device folder name: 0000:ff:0b.1
+            #
+            # The folder name is built from:
+            #   4 hex digit of domain
+            #   colon ':'
+            #   2 hex digit of bus - this is what we are looking for
+            #   colon ':'
+            #   2 hex digit of id
+            #   dot '.'
+            #   1 digit of fn
+            pattern_for_device_folder = re.search('....:(..):..\..', folder)
+            if pattern_for_device_folder:
+                bus = pattern_for_device_folder.group(1)
+                with open(os.path.join('/sys/bus/pci/devices', folder, 'device'), 'r') as device_file:
+                    # The 'device' file contain an hex repesantaion of the id key in the yaml file.
+                    # Example of the file contact:
+                    # 0x6fe2
+                    # We will strip the new line character, and remove the 0x prefix that is not needed.
+                    device_id = device_file.read().strip().replace('0x', '')
+                    self._device_id_to_bus_map[device_id] = bus
+
+    def __init__(self, platform_path):
+        PcieUtil.__init__(self, platform_path)
+        self._create_device_id_to_bus_map()