[devices]: Poller to detect Intel Rangely LPC failure for dell z9100/s6100 (#3065)

- What I did
Added Daemon to Log LPC bus degradation in Intel C2000 processor. Intel Rangeley C2000 processors with revision less than or equal to 2 have issue where LPC bus degrades over time in some processors. To identify the problem and to notify the issue, a daemon has been added which will log on encountering the issue.

- How I did it
Added a daemon which validates the CPLD scratch(0x102) and SMF scratch(0x202) registers by writing and reading values on regular polling intervals (300 seconds). If there is a discrepancy between read and write, a critical log will be thrown.

- How to verify it
The infra is verify by simulating the issue where between write and read, the value in register is modified and the log appearance is checked.

- Description for the changelog

Added Daemon to identify LPC bus degradation issue and notify using syslog in Dell S6100 and Z9100 platforms. This daemon will only run on processors with revision less than or equal to 2.

platform/broadcom/sonic-platform-modules-dell/common/dell_lpc_mon.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+REV=$(lspci -xxx -s 0:0.0 | grep rev | awk -F 'rev ' '{print $2}' | sed 's/)//')
+if [ $REV -gt 2 ]
+then
+    exit 0
+fi
+
+test_val=(55 aa)
+num_val=${#test_val[@]}
+index=0
+poll_interval=300
+cpld_scratch_reg=0x102
+smf_scratch_reg=0x202
+
+function log_crit() {
+   local msg=$1
+
+  `logger -p user.crit -t DELL_LPC_BUS_MON $msg`
+}
+
+function validate_lpc() {
+    local reg=$1
+    local val=$2
+    local reg_str="CPLD scratch register"
+
+    if [ $reg == $smf_scratch_reg ]
+    then
+        reg_str="SMF scratch register"
+    fi
+    io_rd_wr.py --set --val $val --offset $reg
+    get_val=$(io_rd_wr.py  --get --offset $reg | cut -d " " -f3)
+    if [ $val != $get_val ]
+    then
+        log_crit "LPC bus has deteriorated on this unit. \
+                  $reg_str has value $get_val while expected is $val \
+                  Please contact technical support"
+    fi
+}
+while true
+do
+    val=${test_val[$index]}
+    validate_lpc $cpld_scratch_reg $val
+    validate_lpc $smf_scratch_reg $val
+    index=$(((index+1)%num_val))
+    sleep $poll_interval
+done

platform/broadcom/sonic-platform-modules-dell/debian/platform-modules-s6100.install

@@ -4,9 +4,11 @@ common/dell_i2c_utils.sh usr/local/bin
 common/io_rd_wr.py usr/local/bin
 common/fstrim.timer etc/systemd/system
 common/fstrim.service etc/systemd/system
+common/dell_lpc_mon.sh usr/local/bin
 s6100/scripts/platform_sensors.py usr/local/bin
 s6100/scripts/platform_watchdog_enable.sh usr/local/bin
 s6100/scripts/platform_watchdog_disable.sh usr/local/bin
 s6100/scripts/sensors usr/bin
 s6100/systemd/platform-modules-s6100.service etc/systemd/system
 s6100/modules/sonic_platform-1.0-py2-none-any.whl usr/share/sonic/device/x86_64-dell_s6100_c2538-r0
+s6100/systemd/s6100-lpc-monitor.service etc/systemd/system

platform/broadcom/sonic-platform-modules-dell/debian/platform-modules-s6100.postinst

@@ -8,4 +8,8 @@ systemctl start fstrim.timer
 depmod -a 
 systemctl enable platform-modules-s6100.service
 systemctl start platform-modules-s6100.service
+
+systemctl enable s6100-lpc-monitor.service
+systemctl start s6100-lpc-monitor.service
+
 #DEBHELPER#

platform/broadcom/sonic-platform-modules-dell/debian/platform-modules-z9100.install

@@ -1,6 +1,7 @@
 z9100/scripts/check_qsfp.sh usr/local/bin
 z9100/scripts/z9100_platform.sh usr/local/bin
 common/dell_i2c_utils.sh usr/local/bin
+common/dell_lpc_mon.sh usr/local/bin
 common/io_rd_wr.py usr/local/bin
 common/fstrim.timer etc/systemd/system
 common/fstrim.service etc/systemd/system
@@ -10,3 +11,4 @@ z9100/scripts/sensors usr/bin
 z9100/modules/sonic_platform-1.0-py2-none-any.whl usr/share/sonic/device/x86_64-dell_z9100_c2538-r0
 z9100/cfg/z9100-modules.conf etc/modules-load.d
 z9100/systemd/platform-modules-z9100.service etc/systemd/system
+z9100/systemd/z9100-lpc-monitor.service etc/systemd/system

platform/broadcom/sonic-platform-modules-dell/debian/platform-modules-z9100.postinst

@@ -10,4 +10,7 @@ systemctl enable platform-modules-z9100.service
 systemctl start platform-modules-z9100.service
 
 
+systemctl enable z9100-lpc-monitor.service
+systemctl start z9100-lpc-monitor.service
+
 #DEBHELPER#

platform/broadcom/sonic-platform-modules-dell/s6100/systemd/s6100-lpc-monitor.service

@@ -0,0 +1,12 @@
+[Unit]
+Description=Dell S6100 LPC bus monitoring poller
+DefaultDependencies=no
+
+[Service]
+User=root
+ExecStart=/usr/local/bin/dell_lpc_mon.sh
+RemainAfterExit=yes
+
+[Install]
+WantedBy=multi-user.target
+

platform/broadcom/sonic-platform-modules-dell/z9100/systemd/z9100-lpc-monitor.service

@@ -0,0 +1,12 @@
+[Unit]
+Description=Dell Z9100 LPC bus monitoring poller
+DefaultDependencies=no
+
+[Service]
+User=root
+ExecStart=/usr/local/bin/dell_lpc_mon.sh
+RemainAfterExit=yes
+
+[Install]
+WantedBy=multi-user.target
+