Fix SAFT to work on all x86 platforms using crossystem.

chromeos_interface.py

 #!/usr/bin/python
 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 '''A module to provide interface to ChromeOS services.'''
 
 import datetime
 import os
 import re
 import shutil
 import struct
 import subprocess
 import tempfile
 import time
 
 class ChromeOSInterfaceError(Exception):
     '''ChromeOS interface specific exception.'''
     pass
 
 class Crossystem(object):
     '''A wrapper for the crossystem utility.'''
 
+    # Code dedicated for user triggering recovery mode through crossystem.
+    USER_RECOVERY_REQUEST_CODE = '193'
+
+    '''
+    The first three legacy boot vector digits are the boot vector base (the
+    entire vector consists of 5 digits). They used to be reported by the BIOS
+    through ACPI, but that scheme has been superseded by the 'crossystem'
+    interface.
+
+    The digits of the boot vector base have the following significance
+
+    - first digit -
+    1 - normal boot
+    2 - developer mode boot
+    3 - recovery initialed by pressing the recovery button
+    4 - recovery from developer mode warning screen
+    5 - recovery caused by both firmware images being invalid
+    6 - recovery caused by both kernel images being invalid
+    8 - recovery initiated by user
+
+    - second digit -
+    0 - recovery firmware
+    1 - rewritable firmware A
+    2 - rewritable firmware B
+
+    - third digit -
+    0 - Read only (recovery) EC firmware
+    1 - rewritable EC firmware
+
+
+    Below is a list of dictionaries to map current system state as reported by
+    'crossystem' into the 'legacy' boot vector digits.
+
+    The three elements of the list represent the three digits of the boot
+    vector. Each list element is a dictionary where the key is the legacy boot
+    vector value in the appropriate position, and the value is in turn a
+    dictionary of name-value pairs.
+
+    If all name-value pairs of a dictionary element match those reported by
+    crossystem, the legacy representation number is considered the appropriate
+    vector digit.
+
+    Note that on some platforms (namely, Mario) same parameters returned by
+    crossystem are set to a wrong value. The class init() routine adjust the
+    list to support those platforms.
+    '''
+
+    VECTOR_MAPS = [
+        { # first vector position
+            '1': {
+                'devsw_boot': '0',
+                'mainfw_type': 'normal',
+                'recoverysw_boot': '0',
+                },
+            '5': {
+                'devsw_boot': '0',
+                'recoverysw_boot': '0',
+                'recovery_reason' : '3',
+                'mainfw_type': 'recovery',
+                },
+            '6': {
+                'devsw_boot': '0',
+                'recoverysw_boot': '0',
+                'recovery_reason' : '66',
+                'mainfw_type': 'recovery',
+                },
+            '8': {
+                'devsw_boot': '0',
+                'recoverysw_boot': '0',
+                'recovery_reason' : USER_RECOVERY_REQUEST_CODE,
+                'mainfw_type': 'recovery',
+                },
+            },
+        { # second vector position
+            '0': {'mainfw_type': 'recovery',},
+            '1': {
+                'mainfw_type': 'normal',
+                'mainfw_act': 'A'
+                },
+            '2': {
+                'mainfw_type': 'normal',
+                'mainfw_act': 'B'
+                },
+            },
+        { # third vector position
+            '0': {'ecfw_act': 'RO',},
+            '1': {'ecfw_act': 'RW',},
+            },
+        ]
+
     def init(self, cros_if):
+        '''Init the instance. If running on Mario - adjust the map.'''
+
         self.cros_if = cros_if
 
+        # Hack Alert!!! Adjust vector map to work on Mario
+        fwid = self.__getattr__('fwid').lower()
+        if not 'mario' in fwid:
+            return
+        # Mario firmware is broken and always reports recovery switch as set
+        # at boot time when booting up in recovery mode. This is why we
+        # exclude recoverysw_boot from the map when running on mario.
+        for state in self.VECTOR_MAPS[0].itervalues():
+            if state['mainfw_type'] != 'recovery':
+                continue
+            if 'recoverysw_boot' in state:
+                del(state['recoverysw_boot'])
+            if state['recovery_reason'] == self.USER_RECOVERY_REQUEST_CODE:
+                # This is the only recovery reason Mario knows about
+                state['recovery_reason'] = '1'
+
     def __getattr__(self, name):
         '''
         Retrieve a crosssystem attribute.
 
         Attempt to access crossystemobject.name will invoke `crossystem name'
         and return the stdout as the value.
         '''
         return self.cros_if.run_shell_command_get_output(
             'crossystem %s' % name)[0]
 
     def __setattr__(self, name, value):
         if name in ('cros_if',):
             self.__dict__[name] = value
         else:
             self.cros_if.run_shell_command('crossystem "%s=%s"' % (name, value))
 
+    def request_recovery(self):
+        '''Request recovery mode next time the target reboots.'''
+
+        self.__setattr__('recovery_request', self.USER_RECOVERY_REQUEST_CODE)
 
     def get_boot_vector_base(self):
-        '''
-        Convert system state into a legacy boot vector base.
+        '''Convert system state into a legacy boot vector base.
 
-        The first three legacy boot vector digits are the boot vector base
-        (the entire vector consists of 5 digits). They used to be reported by
-        the BIOS through ACPI, but that scheme has been superseded by the
-        'crossystem' interface.
+        The function looks up the VECTOR_MAPS list above to find the digits
+        matching the current crossystem output, and returns a list of three
+        digits in symbolic representation, which become the base of the 5
+        digit boot state vector.
 
-        The digits of the boot vector base have the following significance
-
-        - first digit -
-        1 - normal boot
-        2 - developer mode boot
-        3 - recovery initialed by pressing the recovery button
-        4 - recovery from developer mode warning screen
-        5 - recovery caused by both firmware images being invalid
-        6 - recovery caused by both kernel images being invalid
-
-        - second digit -
-        0 - recovery firmware
-        1 - rewritable firmware A
-        2 - rewritable firmware B
-
-        - third digit -
-        0 - Read only (recovery) EC firmware
-        1 - rewritable EC firmware
-
-
-        This function uses a three tuple of dictionaries to map current system
-        state as reported by 'crossystem' into the 'legacy' boot vector
-        digits.
-
-        Each tuple element is a dictionary, where the key is the 'legacy'
-        representation of the state, and the value is a yet another dictionary
-        of name-value pairs.
-
-        If all name-value pairs match those in the crossystem output, the
-        legacy representation number is returned as the appropriate vector
-        number.
-
-        The function returns a list of three digits in symbolic representation.
-
-        Should it be impossible to interpret the state, the function returns a
-        partially built list, which is an indication of a problem for the
+        Should it be impossible to interpret the state, the function returns
+        a partially built list, which is an indication of a problem for the
         caller (list shorter than 3 elements).
         '''
 
-        vector_maps = (
-            { # first vector position
-                '1': {
-                    'devsw_boot': '0',
-                    'recoverysw_boot': '0',
-                    'recovery_reason' : '0',
-                    'tried_fwb' : '0',
-                    },
-                },
-            { # second vector position
-                '0': {'mainfw_type': 'recovery',},
-                '1': {
-                    'mainfw_type': 'normal',
-                    'mainfw_act': 'A'
-                    },
-                '2': {
-                    'mainfw_type': 'normal',
-                    'mainfw_act': 'B'
-                    },
-                },
-            { # third vector position
-                '0': {'ecfw_act': 'RO',},
-                '1': {'ecfw_act': 'RW',},
-                },
-        )
-
         boot_vector = []
 
-        for vector_map in vector_maps:
+        for vector_map in self.VECTOR_MAPS:
             for (digit, values) in vector_map.iteritems():
                 for (name, value) in values.iteritems():
                     if self.__getattr__(name) != value:
                         break
                 else:
                     boot_vector.append(digit)
                     break
 
         return boot_vector
 
     def dump(self):
-        '''Dump all values as multiline text.'''
+        '''Dump all crossystem values as multiline text.'''
+
         return '\n'.join(self.cros_if.run_shell_command_get_output(
             'crossystem'))
 
 
 class ChromeOSInterface(object):
     '''An object to encapsulate OS services functions.'''
 
     def __init__(self, silent):
         '''Object construction time initialization.
 
@@ skipping 233 matching lines @@
     def read_partition(self, partition, size):
         '''Read the requested partition, up to size bytes.'''
         tmp_file = self.state_dir_file('part.tmp')
         self.run_shell_command('dd if=%s of=%s bs=1 count=%d' % (
                 partition, tmp_file, size))
         fileh = open(tmp_file, 'r')
         data = fileh.read()
         fileh.close()
         os.remove(tmp_file)
         return data