[devices]: DellEmc-Z9264f:Interrupt based Optic OIR (sonic-net#2926)

Author: gengankarthik

device/dell/x86_64-dellemc_z9264f_c3538-r0/plugins/sfputil.py

@@ -8,6 +8,7 @@
     import sys
     import getopt
     import time
+    import select
     from sonic_sfp.sfputilbase import SfpUtilBase
     from os import *
     from mmap import *
@@ -24,6 +25,10 @@ class SfpUtil(SfpUtilBase):
     PORTS_IN_BLOCK = 64
 
     BASE_RES_PATH = "/sys/bus/pci/devices/0000:04:00.0/resource0"
+    OIR_FD_PATH = "/sys/bus/pci/devices/0000:04:00.0/port_msi"
+
+    oir_fd = -1
+    epoll = -1
 
     _port_to_eeprom_mapping = {}
 
@@ -47,16 +52,16 @@ def port_to_eeprom_mapping(self):
 
     def pci_mem_read(self, mm, offset):
         mm.seek(offset)
-        read_data_stream=mm.read(4)
-        reg_val=struct.unpack('I',read_data_stream)
+        read_data_stream = mm.read(4)
+        reg_val = struct.unpack('I', read_data_stream)
         mem_val = str(reg_val)[1:-2]
         # print "reg_val read:%x"%reg_val
         return mem_val
 
     def pci_mem_write(self, mm, offset, data):
         mm.seek(offset)
         # print "data to write:%x"%data
-        mm.write(struct.pack('I',data))
+        mm.write(struct.pack('I', data))
 
     def pci_set_value(self, resource, val, offset):
         fd = open(resource, O_RDWR)
@@ -73,25 +78,23 @@ def pci_get_value(self, resource, offset):
         mm.close()
         close(fd)
         return val
-	
+
     def init_global_port_presence(self):
         for port_num in range(self.port_start, (self.port_end + 1)):
             presence = self.get_presence(port_num)
             if(presence):
                 self._global_port_pres_dict[port_num] = '1'
             else:
                 self._global_port_pres_dict[port_num] = '0'
- 
+
     def __init__(self):
         eeprom_path = "/sys/class/i2c-adapter/i2c-{0}/{0}-0050/eeprom"
 
         for x in range(self.port_start, self.port_end + 1):
-            port_num  = x + 1
-            self.port_to_eeprom_mapping[x] = eeprom_path.format(
-                        port_num)
+            port_num = x + 1
+            self.port_to_eeprom_mapping[x] = eeprom_path.format(port_num)
             port_num = 0
         self.init_global_port_presence()
-        
         SfpUtilBase.__init__(self)
 
     def get_presence(self, port_num):
@@ -100,13 +103,13 @@ def get_presence(self, port_num):
             return False
 
         # Port offset starts with 0x4004
-	port_offset = 16388 + ((port_num-1) * 16)
+        port_offset = 16388 + ((port_num-1) * 16)
+
+        status = self.pci_get_value(self.BASE_RES_PATH, port_offset)
+        reg_value = int(status)
 
-	status = self.pci_get_value(self.BASE_RES_PATH, port_offset)
-	reg_value = int(status)
-        
         # Absence of status throws error
-        if (reg_value == "" ):
+        if (reg_value == ""):
             return False
 
         # Mask off 4th bit for presence
@@ -124,14 +127,14 @@ def get_low_power_mode(self, port_num):
         if port_num < self.port_start or port_num > self.port_end:
             return False
 
-	# Port offset starts with 0x4000
-	port_offset = 16384 + ((port_num-1) * 16)
+        # Port offset starts with 0x4000
+        port_offset = 16384 + ((port_num-1) * 16)
 
-	status = self.pci_get_value(self.BASE_RES_PATH, port_offset)
-	reg_value = int(status)
+        status = self.pci_get_value(self.BASE_RES_PATH, port_offset)
+        reg_value = int(status)
 
         # Absence of status throws error
-        if (reg_value == "" ):
+        if (reg_value == ""):
             return False
 
         # Mask off 4th bit for presence
@@ -149,44 +152,44 @@ def set_low_power_mode(self, port_num, lpmode):
         if port_num < self.port_start or port_num > self.port_end:
             return False
 
-	# Port offset starts with 0x4000
-	port_offset = 16384 + ((port_num-1) * 16)
+        # Port offset starts with 0x4000
+        port_offset = 16384 + ((port_num-1) * 16)
 
-	status = self.pci_get_value(self.BASE_RES_PATH, port_offset)
-	reg_value = int(status)
+        status = self.pci_get_value(self.BASE_RES_PATH, port_offset)
+        reg_value = int(status)
 
         # Absence of status throws error
-        if (reg_value == "" ):
+        if (reg_value == ""):
             return False
 
         # Mask off 4th bit for presence
         mask = (1 << 6)
-		
-	# LPMode is active high; set or clear the bit accordingly
+
+        # LPMode is active high; set or clear the bit accordingly
         if lpmode is True:
             reg_value = reg_value | mask
         else:
             reg_value = reg_value & ~mask
 
         # Convert our register value back to a hex string and write back
-	status = self.pci_set_value(self.BASE_RES_PATH, reg_value, port_offset)
+        status = self.pci_set_value(self.BASE_RES_PATH, reg_value, port_offset)
 
         return True
 
     def reset(self, port_num):
 
-	# Check for invalid port_num
+        # Check for invalid port_num
         if port_num < self.port_start or port_num > self.port_end:
             return False
 
-	# Port offset starts with 0x4000
-	port_offset = 16384 + ((port_num-1) * 16)
+        # Port offset starts with 0x4000
+        port_offset = 16384 + ((port_num-1) * 16)
 
-	status = self.pci_get_value(self.BASE_RES_PATH, port_offset)
-	reg_value = int(status)
+        status = self.pci_get_value(self.BASE_RES_PATH, port_offset)
+        reg_value = int(status)
 
         # Absence of status throws error
-        if (reg_value == "" ):
+        if (reg_value == ""):
             return False
 
         # Mask off 4th bit for presence
@@ -195,33 +198,106 @@ def reset(self, port_num):
         # ResetL is active low
         reg_value = reg_value & ~mask
 
-	# Convert our register value back to a hex string and write back
-	status = self.pci_set_value(self.BASE_RES_PATH, reg_value, port_offset)
+        # Convert our register value back to a hex string and write back
+        status = self.pci_set_value(self.BASE_RES_PATH, reg_value, port_offset)
 
         # Sleep 1 second to allow it to settle
         time.sleep(1)
 
         reg_value = reg_value | mask
 
-	# Convert our register value back to a hex string and write back
-	status = self.pci_set_value(self.BASE_RES_PATH, reg_value, port_offset)
+        # Convert our register value back to a hex string and write back
+        status = self.pci_set_value(self.BASE_RES_PATH, reg_value, port_offset)
 
         return True
 
-    def get_transceiver_change_event(self):
-        port_dict = {}
-        while True:
+    def get_register(self, reg_file):
+            retval = 'ERR'
+            if (not path.isfile(reg_file)):
+                print reg_file,  'not found !'
+                return retval
+
+            try:
+                with fdopen(open(reg_file, O_RDONLY)) as fd:
+                    retval = fd.read()
+            except Exception as error:
+                logging.error("Unable to open ", reg_file, "file !")
+
+            retval = retval.rstrip('\r\n')
+            retval = retval.lstrip(" ")
+            return retval
+
+    def check_interrupts(self, port_dict):
+            retval = 0
+            is_port_dict_updated = False
             for port_num in range(self.port_start, (self.port_end + 1)):
                 presence = self.get_presence(port_num)
                 if(presence and self._global_port_pres_dict[port_num] == '0'):
+                    is_port_dict_updated = True
                     self._global_port_pres_dict[port_num] = '1'
                     port_dict[port_num] = '1'
                 elif(not presence and
                      self._global_port_pres_dict[port_num] == '1'):
+                    is_port_dict_updated = True
                     self._global_port_pres_dict[port_num] = '0'
                     port_dict[port_num] = '0'
-
-                if(len(port_dict) > 0):
-                    return True, port_dict
-
-            time.sleep(0.5)
+            return retval, is_port_dict_updated
+
+    def get_transceiver_change_event(self, timeout=0):
+            port_dict = {}
+            try:
+                # We get notified when there is a MSI interrupt (vector 4/5)CVR
+                # Open the sysfs file and register the epoll object
+                self.oir_fd = fdopen(open(self.OIR_FD_PATH, O_RDONLY))
+                if self.oir_fd != -1:
+                    # Do a dummy read before epoll register
+                    self.oir_fd.read()
+                    self.epoll = select.epoll()
+                    self.epoll.register(
+                        self.oir_fd.fileno(), select.EPOLLIN & select.EPOLLET)
+                else:
+                    print("get_transceiver_change_event : unable to create fd")
+                    return False, {}
+
+                # Check for missed interrupts by invoking self.check_interrupts
+                # which will update the port_dict.
+                while True:
+                    interrupt_count_start = self.get_register(self.OIR_FD_PATH)
+                    retval, is_port_dict_updated = \
+                        self.check_interrupts(port_dict)
+                    if ((retval == 0) and (is_port_dict_updated is True)):
+                        return True, port_dict
+                    interrupt_count_end = self.get_register(self.OIR_FD_PATH)
+                    if (interrupt_count_start == 'ERR' or
+                            interrupt_count_end == 'ERR'):
+                        print("get_transceiver_change_event : \
+                            unable to retrive interrupt count")
+                        break
+
+                    # check_interrupts() itself may take upto 100s of msecs.
+                    # We detect a missed interrupt based on the count
+                    if interrupt_count_start == interrupt_count_end:
+                        break
+
+                # Block until an xcvr is inserted or removed with timeout = -1
+                events = self.epoll.poll(
+                    timeout=timeout if timeout != 0 else -1)
+                if events:
+                    # check interrupts and return the port_dict
+                    retval, is_port_dict_updated = \
+                                              self.check_interrupts(port_dict)
+                    if (retval != 0):
+                        return False, {}
+
+                return True, port_dict
+            except:
+                return False, {}
+            finally:
+                if self.oir_fd != -1:
+                    self.epoll.unregister(self.oir_fd.fileno())
+                    self.epoll.close()
+                    self.oir_fd.close()
+                    self.oir_fd = -1
+                    self.epoll = -1
+
+            return False, {}

platform/broadcom/sonic-platform-modules-dell/debian/platform-modules-z9264f.install

@@ -3,6 +3,7 @@ z9264f/scripts/check_qsfp.sh usr/local/bin
 z9264f/scripts/platform_sensors.py usr/local/bin
 z9264f/scripts/sensors usr/bin
 z9264f/scripts/pcisysfs.py usr/bin
+z9264f/scripts/qsfp_irq_enable.py usr/bin
 z9264f/cfg/z9264f-modules.conf etc/modules-load.d
 z9264f/systemd/platform-modules-z9264f.service etc/systemd/system
 common/platform_reboot usr/share/sonic/device/x86_64-dellemc_z9264f_c3538-r0