pytools: obmcutil: Add `chassiskill` command
Nick reported an issue where the BMC became unusable after the host hit
a bug and began "spewing a lot of messages to the console". Save
ourselves some DBus transactions and immediate execution of systemd
transitions by introducing a `chassiskill` command to directly deassert
the the power-up GPIO ourselves. This will immediately terminate the
host and free up resources for the BMC to become responsive. As a bonus,
the PGOOD monitoring will then execute to clean up the resulting
inconsistent BMC/Host state for us.
Change-Id: I106a4202b6544b8e78b04938230a4eeee5f132bb
Requested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/pytools/obmcutil b/pytools/obmcutil
index e2b422a..30db80c 100644
--- a/pytools/obmcutil
+++ b/pytools/obmcutil
@@ -11,6 +11,9 @@
import time
from subprocess import Popen
+import obmc_system_config
+import obmc.system
+
descriptors = {
'power': {
'bus_name': 'org.openbmc.control.Power',
@@ -178,9 +181,79 @@
return True
+def gpio_set_value(gpio_name, active_low, asserted):
+ gpio_id = obmc.system.convertGpio(gpio_name)
+ gpio_value_path = "/sys/class/gpio/gpio{}/value".format(gpio_id)
+
+ with open(gpio_value_path, 'w') as gpio:
+ # Inversion behaviour needs to change with the resolution of
+ # https://github.com/openbmc/openbmc/issues/2489, where properly
+ # configuring the kernel will allow it to handle the inversion for us.
+ gpio.write(str(int(asserted ^ active_low)))
+
+ return True
+
+def gpio_deassert(gpio_name, active_low, args):
+ # Deal with silly python2 exception handling as outlined in main
+ if args.verbose:
+ return gpio_set_value(gpio_name, active_low, False)
+
+ try:
+ return gpio_set_value(gpio_name, active_low, False)
+ except IOError as e:
+ print >> sys.stderr, "Failed to access GPIO {}: {}".format(gpio_name, e.message)
+ return False
+
+def run_chassiskill(args):
+ # We shouldn't be able to invoke run_chassiskill() unless it's been
+ # explicitly added as a valid command to argparse in main()
+ assert can_chassiskill()
+
+ # Multi-dimensional fetch is now exception-safe
+ gpios = obmc_system_config.GPIO_CONFIGS['power_config']['power_up_outs']
+
+ gc = obmc_system_config.GPIO_CONFIG
+
+ for gpio in gpios:
+ function = gpio[0]
+
+ if function not in gc or 'gpio_pin' not in gc[function]:
+ print >> sys.stderr, "Missing or invalid definition for '{}' in system GPIO_CONFIG".format(function)
+ continue
+
+ name = gc[function]['gpio_pin']
+
+ # The second element of the tuples stashed in 'power_up_outs'
+ # represents the boolean condition of the statement 'active high'. To
+ # mirror the code at [1] we instead need the condition of the statement
+ # 'active low', thus we negate gpio[1].
+ #
+ # [1] https://github.com/openbmc/skeleton/blob/93b84e42834893313616f96c70743369f26a7190/op-pwrctl/power_control_obj.c#L283
+ active_low = not gpio[1]
+
+ if not gpio_deassert(name, active_low, args):
+ return False
+
+ return True
+
+def can_chassiskill():
+ gcs = obmc_system_config.GPIO_CONFIGS
+
+ if 'power_config' in gcs:
+ if 'power_up_outs' in gcs['power_config']:
+ # Just to be sure
+ return len(gcs['power_config']) > 0
+
+ return False
+
def main():
dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
+ # Conditionally add the `chassiskill` commmand based on whether the
+ # required GPIO configuration is present in the system description.
+ if can_chassiskill():
+ descriptors['chassiskill'] = None
+
parser = argparse.ArgumentParser()
parser.add_argument('--verbose', '-v', action='store_true',
help="Verbose output")
@@ -192,6 +265,11 @@
parser.add_argument('recipe', choices=sorted(descriptors.keys()))
args = parser.parse_args()
+ # This is a special case: directly pull the power, don't do any D-Bus
+ # related stuff
+ if args.recipe == "chassiskill":
+ return run_chassiskill(args)
+
dbus_bus = dbus.SystemBus()
# The only way to get a sensible backtrace with python 2 without stupid