1 # 2 # Copyright 2015 ARM Limited 3 # 4 # Licensed under the Apache License, Version 2.0 (the "License"); 5 # you may not use this file except in compliance with the License. 6 # You may obtain a copy of the License at 7 # 8 # http://www.apache.org/licenses/LICENSE-2.0 9 # 10 # Unless required by applicable law or agreed to in writing, software 11 # distributed under the License is distributed on an "AS IS" BASIS, 12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 # See the License for the specific language governing permissions and 14 # limitations under the License. 15 # 16 import re 17 import time 18 import logging 19 20 from devlib.utils.serial_port import TIMEOUT 21 22 23 logger = logging.getLogger('U-Boot') 24 25 26 class UbootMenu(object): 27 """ 28 Allows navigating Das U-boot menu over serial (it relies on a pexpect connection). 29 30 """ 31 32 option_regex = re.compile(r'^\[(\d+)\]\s+([^\r]+)\r\n', re.M) 33 prompt_regex = re.compile(r'^([^\r\n]+):\s*', re.M) 34 invalid_regex = re.compile(r'Invalid input \(max (\d+)\)', re.M) 35 36 load_delay = 1 # seconds 37 default_timeout = 60 # seconds 38 39 def __init__(self, conn, start_prompt='Hit any key to stop autoboot'): 40 """ 41 :param conn: A serial connection as returned by ``pexect.spawn()``. 42 :param prompt: U-Boot menu prompt 43 :param start_prompt: The starting prompt to wait for during ``open()``. 44 45 """ 46 self.conn = conn 47 self.conn.crlf = '\n\r' # TODO: this has *got* to be a bug in U-Boot... 48 self.start_prompt = start_prompt 49 self.options = {} 50 self.prompt = None 51 52 def open(self, timeout=default_timeout): 53 """ 54 "Open" the UEFI menu by sending an interrupt on STDIN after seeing the 55 starting prompt (configurable upon creation of the ``UefiMenu`` object. 56 57 """ 58 self.conn.expect(self.start_prompt, timeout) 59 self.conn.sendline('') 60 time.sleep(self.load_delay) 61 self.conn.readline() # garbage 62 self.conn.sendline('') 63 self.prompt = self.conn.readline().strip() 64 65 def getenv(self): 66 output = self.enter('printenv') 67 result = {} 68 for line in output.split('\n'): 69 if '=' in line: 70 variable, value = line.split('=', 1) 71 result[variable.strip()] = value.strip() 72 return result 73 74 def setenv(self, variable, value, force=False): 75 force_str = ' -f' if force else '' 76 if value is not None: 77 command = 'setenv{} {} {}'.format(force_str, variable, value) 78 else: 79 command = 'setenv{} {}'.format(force_str, variable) 80 return self.enter(command) 81 82 def boot(self): 83 self.write_characters('boot') 84 85 def nudge(self): 86 """Send a little nudge to ensure there is something to read. This is useful when you're not 87 sure if all out put from the serial has been read already.""" 88 self.enter('') 89 90 def enter(self, value, delay=load_delay): 91 """Like ``select()`` except no resolution is performed -- the value is sent directly 92 to the serial connection.""" 93 # Empty the buffer first, so that only response to the input about to 94 # be sent will be processed by subsequent commands. 95 value = str(value) 96 self.empty_buffer() 97 self.write_characters(value) 98 self.conn.expect(self.prompt, timeout=delay) 99 return self.conn.before 100 101 def write_characters(self, line): 102 line = line.rstrip('\r\n') 103 for c in line: 104 self.conn.send(c) 105 time.sleep(0.05) 106 self.conn.sendline('') 107 108 def empty_buffer(self): 109 try: 110 while True: 111 time.sleep(0.1) 112 self.conn.read_nonblocking(size=1024, timeout=0.1) 113 except TIMEOUT: 114 pass 115 self.conn.buffer = '' 116 117
