[device]: DellEmc-S6000 : Back-end work for last reboot reason (#2974)

* DellEmc-S6000 Backend work for lastreboot reason

device/dell/x86_64-dell_s6000_s1220-r0/platform_reboot

@@ -1,13 +1,56 @@
-#!/bin/sh
+#!/usr/bin/python
+import sys
+import os
+import struct
 
-# Export GPIO10 if needed
-[ -d /sys/class/gpio/gpio10 ] || echo 10 > /sys/class/gpio/export
-echo out > /sys/class/gpio/gpio10/direction
+NVRAM_RES = '/dev/nvram'
+COLD_RESET = 0xE     # Cold Reset 
+WARM_RESET = 0x6     # Warm Reset 
 
-#Toggle GPIO10 pin (to reset MUX)
-echo 1 > /sys/class/gpio/gpio10/value
-echo 0 > /sys/class/gpio/gpio10/value
+def io_reg_write(resource, offset, val):
+    fd = os.open(resource, os.O_RDWR)
+    if(fd < 0):
+        print 'file open failed %s" % resource'
+        return
+    if(os.lseek(fd, offset, os.SEEK_SET) != offset):
+        print 'lseek failed on %s' % resource
+        return
+    ret = os.write(fd, struct.pack('B', val))
+    if(ret != 1):
+        print 'write failed %d' % ret
+        return
+    os.close(fd)
 
 
-#Power Reset
-echo 1 > /sys/devices/platform/dell-s6000-cpld.0/power_reset
+def power_reset(val):
+    with open('/sys/devices/platform/dell-s6000-cpld.0/power_reset', 'w') as p:
+        p.write(str(int(val)) + '\n')
+        p.flush()
+
+def gpio_direction(pin,direction):
+    kernpath = '/sys/class/gpio/gpio'+str(pin)+'/direction'
+    with open(('kernpath'), 'w') as p:
+        p.write(str(direction) + '\n')
+        p.flush()
+
+def gpio_set(pin,value):
+    kernpath = '/sys/class/gpio/gpio'+str(pin)+'/value'
+    with open(('kernpath'), 'w') as p:
+        p.write(str(int(value)) + '\n')
+        p.flush()
+
+def gpio_export(value):
+    with open('/sys/class/gpio/export', 'w') as p:
+        p.write(str(int(value)) + '\n')
+        p.flush()
+
+
+if __name__ == "__main__":
+    io_reg_write(NVRAM_RES, 0x49, COLD_RESET)
+    if not os.path.isdir("/sys/class/gpio/gpio10"):
+        gpio_export(10)
+    gpio_direction("10","out")
+    #Toggle GPIO10 pin (to reset MUX)
+    gpio_set("10",1)
+    gpio_set("10",0)
+    power_reset(1)

platform/broadcom/sonic-platform-modules-s6000/debian/platform-modules-s6000.init

@@ -67,6 +67,7 @@ start)
         depmod -a
         modprobe i2c_mux_gpio
         modprobe dell_s6000_platform
+        modprobe nvram
 
         add_i2c_devices
 
@@ -81,6 +82,7 @@ stop)
 
         remove_i2c_devices
 
+        rmmod nvram
         rmmod dell_s6000_platform
         rmmod i2c_mux_gpio
 	;;

platform/broadcom/sonic-platform-modules-s6000/debian/platform-modules-s6000.install

@@ -1 +1,2 @@
 systemd/platform-modules-s6000.service lib/systemd/system
+scripts/io_rd_wr.py usr/local/bin

platform/broadcom/sonic-platform-modules-s6000/scripts/io_rd_wr.py

@@ -0,0 +1,93 @@
+#!/usr/bin/python
+#Script to read/write the io based registers
+
+import sys
+import os
+import getopt
+import struct
+
+io_resource='/dev/port'
+
+def usage():
+    ''' This is the Usage Method '''
+
+    print 'Utility for IO read/write'
+    print '\t\t io_rd_wr.py --get --offset <offset>'
+    print '\t\t io_rd_wr.py --set --val <val>  --offset <offset>'
+    sys.exit(1)
+
+def io_reg_read(io_resource,offset):
+    fd=os.open(io_resource, os.O_RDONLY)
+    if(fd<0):
+        print 'file open failed %s"%io_resource'
+        return
+    if(os.lseek(fd, offset, os.SEEK_SET) != offset):
+        print 'lseek failed on %s'%io_resource
+        return
+    buf=os.read(fd,1)
+    reg_val1=ord(buf)
+    print 'reg value %x'%reg_val1
+    os.close(fd)
+
+def io_reg_write(io_resource,offset,val):
+    fd=os.open(io_resource,os.O_RDWR)
+    if(fd<0):
+        print 'file open failed %s"%io_resource'
+        return
+    if(os.lseek(fd, offset, os.SEEK_SET) != offset):
+        print 'lseek failed on %s'%io_resource
+        return
+    ret=os.write(fd,struct.pack('B',val))
+    if(ret != 1):
+        print 'write failed %d'%ret
+        return
+    os.close(fd)
+
+def main(argv):
+
+    ''' The main function will read the user input from the
+    command line argument and  process the request  '''
+
+    opts = ''
+    val = ''
+    choice = ''
+    resouce = ''
+    offset = ''
+
+    try:
+        opts, args = getopt.getopt(argv, "hgs:" , \
+        ["val=","offset=","help", "get", "set"])
+    
+    except getopt.GetoptError:
+        usage()
+
+    for opt,arg in opts:
+
+        if opt in ('-h','--help'):
+            choice = 'help'
+
+        elif opt in ('-g', '--get'):
+            choice = 'get'
+
+        elif opt in ('-s', '--set'):
+            choice = 'set'
+
+        elif opt ==  '--offset':
+            offset = int(arg,16)
+
+        elif opt ==  '--val':
+            val = int(arg,16)
+
+    if choice == 'get' and offset != '':
+        io_reg_read(io_resource,offset)
+
+    elif choice == 'set' and offset != '' and val != '':
+        io_reg_write(io_resource,offset,val)
+
+    else:
+        usage()
+
+#Calling the main method
+if __name__ == "__main__":
+    main(sys.argv[1:])
+