qemu/roms/seabios/scripts/readserial.py

   1 #!/usr/bin/env python
   2 # Script that can read from a serial device and show timestamps.
   3 #
   4 # Copyright (C) 2009  Kevin O'Connor <kevin@koconnor.net>
   5 #
   6 # This file may be distributed under the terms of the GNU GPLv3 license.
   7
   8 # Usage:
   9 #   scripts/readserial.py /dev/ttyUSB0 115200
  10
  11 import sys, os, time, select, optparse
  12
  13 from python23compat import as_bytes
  14
  15 # Reset time counter after this much idle time.
  16 RESTARTINTERVAL = 60
  17 # Number of bits in a transmitted byte - 8N1 is 1 start bit + 8 data
  18 # bits + 1 stop bit.
  19 BITSPERBYTE = 10
  20
  21 def calibrateserialwrite(outfile, byteadjust):
  22     # Build 4000 bytes of dummy data.
  23     data = "0123456789" * 4 + "012345678" + "\n"
  24     data = data * 80
  25     while 1:
  26         st = time.time()
  27         outfile.write(as_bytes(data))
  28         outfile.flush()
  29         et = time.time()
  30         sys.stdout.write(
  31             "Wrote %d - %.1fus per char (theory states %.1fus)\n" % (
  32                 len(data), (et-st) / len(data) * 1000000, byteadjust * 1000000))
  33         sys.stdout.flush()
  34         time.sleep(3)
  35
  36 def calibrateserialread(infile, byteadjust):
  37     starttime = lasttime = 0
  38     totalchars = 0
  39     while 1:
  40         select.select([infile], [], [])
  41         d = infile.read(4096)
  42         curtime = time.time()
  43         if curtime - lasttime > 1.0:
  44             if starttime and totalchars:
  45                 sys.stdout.write(
  46                     "Calibrating on %d bytes - %.1fus per char"
  47                     " (theory states %.1fus)\n" % (
  48                         totalchars,
  49                         float(lasttime - starttime) * 1000000 / totalchars,
  50                         byteadjust * 1000000))
  51             totalchars = 0
  52             starttime = curtime
  53         else:
  54             totalchars += len(d)
  55         lasttime = curtime
  56
  57 def readserial(infile, logfile, byteadjust):
  58     lasttime = 0
  59     while 1:
  60         # Read data
  61         try:
  62             res = select.select([infile, sys.stdin], [], [])
  63         except KeyboardInterrupt:
  64             sys.stdout.write("\n")
  65             return -1
  66         if sys.stdin in res[0]:
  67             # Got keyboard input - force reset on next serial input
  68             sys.stdin.read(1)
  69             lasttime = 0
  70             if len(res[0]) == 1:
  71                 continue
  72         d = infile.read(4096)
  73         if not d:
  74             return 0
  75         datatime = time.time()
  76
  77         datatime -= len(d) * byteadjust
  78
  79         # Reset start time if no data for some time
  80         if datatime - lasttime > RESTARTINTERVAL:
  81             starttime = datatime
  82             charcount = 0
  83             isnewline = 1
  84             msg = "\n\n======= %s (adjust=%.1fus)\n" % (
  85                 time.asctime(time.localtime(datatime)), byteadjust * 1000000)
  86             sys.stdout.write(msg)
  87             logfile.write(as_bytes(msg))
  88         lasttime = datatime
  89
  90         # Translate unprintable chars; add timestamps
  91         out = as_bytes("")
  92         for c in d:
  93             if isnewline:
  94                 delta = datatime - starttime - (charcount * byteadjust)
  95                 out += "%06.3f: " % delta
  96                 isnewline = 0
  97             oc = ord(c)
  98             charcount += 1
  99             datatime += byteadjust
 100             if oc == 0x0d:
 101                 continue
 102             if oc == 0x00:
 103                 out += "<00>\n"
 104                 isnewline = 1
 105                 continue
 106             if oc == 0x0a:
 107                 out += "\n"
 108                 isnewline = 1
 109                 continue
 110             if oc < 0x20 or oc >= 0x7f and oc != 0x09:
 111                 out += "<%02x>" % oc
 112                 continue
 113             out += c
 114
 115         if (sys.version_info > (3, 0)):
 116             sys.stdout.buffer.write(out)
 117         else:
 118             sys.stdout.write(out)
 119         sys.stdout.flush()
 120         logfile.write(out)
 121         logfile.flush()
 122
 123 def main():
 124     usage = "%prog [options] [<serialdevice> [<baud>]]"
 125     opts = optparse.OptionParser(usage)
 126     opts.add_option("-f", "--file",
 127                     action="store_false", dest="serial", default=True,
 128                     help="read from unix named pipe instead of serialdevice")
 129     opts.add_option("-n", "--no-adjust",
 130                     action="store_false", dest="adjustbaud", default=True,
 131                     help="don't adjust times by serial rate")
 132     opts.add_option("-c", "--calibrate-read",
 133                     action="store_true", dest="calibrate_read", default=False,
 134                     help="read from serial port to calibrate it")
 135     opts.add_option("-C", "--calibrate-write",
 136                     action="store_true", dest="calibrate_write", default=False,
 137                     help="write to serial port to calibrate it")
 138     opts.add_option("-t", "--time",
 139                     type="float", dest="time", default=None,
 140                     help="time to write one byte on serial port (in us)")
 141     options, args = opts.parse_args()
 142     serialport = 0
 143     baud = 115200
 144     if len(args) > 2:
 145         opts.error("Too many arguments")
 146     if len(args) > 0:
 147         serialport = args[0]
 148     if len(args) > 1:
 149         baud = int(args[1])
 150     byteadjust = float(BITSPERBYTE) / baud
 151     if options.time is not None:
 152         byteadjust = options.time / 1000000.0
 153     if not options.adjustbaud:
 154         byteadjust = 0.0
 155
 156     if options.serial:
 157         # Read from serial port
 158         try:
 159             import serial
 160         except ImportError:
 161             print("""
 162 Unable to find pyserial package ( http://pyserial.sourceforge.net/ ).
 163 On Linux machines try: yum install pyserial
 164 Or: apt-get install python-serial
 165 """)
 166             sys.exit(1)
 167         ser = serial.Serial(serialport, baud, timeout=0)
 168
 169     if options.calibrate_read:
 170         calibrateserialread(ser, byteadjust)
 171         return
 172     if options.calibrate_write:
 173         calibrateserialwrite(ser, byteadjust)
 174         return
 175
 176     logname = time.strftime("seriallog-%Y%m%d_%H%M%S.log")
 177     f = open(logname, 'wb')
 178     if options.serial:
 179         readserial(ser, f, byteadjust)
 180     else:
 181         # Read from a pipe
 182         while 1:
 183             ser = os.fdopen(os.open(serialport, os.O_RDONLY|os.O_NONBLOCK), 'rb')
 184             res = readserial(ser, f, byteadjust)
 185             ser.close()
 186             if res < 0:
 187                 break
 188
 189 if __name__ == '__main__':
 190     main()