ci/bare-metal: Use python for handling fastboot booting and parsing

Modeling after what I did for cros_servo_run.py, this gives us easy
support for restarting the test run a530 when we detect a spontaneous
reboot.  I had to touch up serial_buffer.py to handle buffering in from a
file instead of a serial device, to support the upcoming etnaviv CI
(tested by running it against a serial log from db410c and seeing it step
to calling "fastboot")

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6529>

.gitlab-ci/bare-metal/fastboot_run.py

@@ -0,0 +1,102 @@
+#!/usr/bin/env python3
+#
+# Copyright © 2020 Google LLC
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the "Software"),
+# to deal in the Software without restriction, including without limitation
+# the rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice (including the next
+# paragraph) shall be included in all copies or substantial portions of the
+# Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+# IN THE SOFTWARE.
+
+import argparse
+import os
+import re
+from serial_buffer import SerialBuffer
+import sys
+import threading
+
+class FastbootRun:
+    def __init__(self, args):
+        self.powerup = args.powerup
+        self.ser = SerialBuffer(args.dev, "results/serial-output.txt", "R SERIAL> ")
+        self.fastboot="fastboot boot -s {ser} artifacts/fastboot.img".format(ser=args.fbserial)
+
+    def logged_system(self, cmd):
+        print("Running '{}'".format(cmd))
+        return os.system(cmd)
+
+    def run(self):
+        if self.logged_system(self.powerup) != 0:
+            return 1
+
+        fastboot_ready = False
+        for line in self.ser.lines():
+            if re.search("fastboot: processing commands", line) or \
+                re.search("Listening for fastboot command on", line):
+                fastboot_ready = True
+                break
+
+            if re.search("data abort", line):
+                return 1
+
+        if not fastboot_ready:
+            print("Failed to get to fastboot prompt")
+            return 1
+
+        if self.logged_system(self.fastboot) != 0:
+            return 1
+
+        for line in self.ser.lines():
+            if re.search("---. end Kernel panic", line):
+                return 1
+
+            # The db820c boards intermittently reboot.  Just restart the run
+            # when if we see a reboot after we got past fastboot.
+            if re.search("PON REASON", line):
+                print("Detected spontaneous reboot, restarting run...")
+                return 2
+
+            result = re.search("bare-metal result: (\S*)", line)
+            if result:
+                if result.group(1) == "pass":
+                    return 0
+                else:
+                    return 1
+
+        print("Reached the end of the CPU serial log without finding a result")
+        return 1
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--dev', type=str, help='Serial device (otherwise reading from serial-output.txt)')
+    parser.add_argument('--powerup', type=str, help='shell command for rebooting', required=True)
+    parser.add_argument('--powerdown', type=str, help='shell command for powering off', required=True)
+    parser.add_argument('--fbserial', type=str, help='fastboot serial number of the board', required=True)
+    args = parser.parse_args()
+
+    fastboot = FastbootRun(args)
+
+    while True:
+        retval = fastboot.run()
+        if retval != 2:
+            break
+
+    fastboot.logged_system(args.powerdown)
+
+    sys.exit(retval)
+
+if __name__ == '__main__':
+    main()