power-sequencer/pgood_monitor.cpp

/**
 * Copyright © 2017 IBM Corporation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#include <phosphor-logging/log.hpp>
#include <xyz/openbmc_project/Power/Fault/error.hpp>
#include "elog-errors.hpp"
#include "pgood_monitor.hpp"
#include "utility.hpp"

namespace witherspoon
{
namespace power
{

constexpr auto POWER_OBJ_PATH = "/org/openbmc/control/power0";
constexpr auto POWER_INTERFACE = "org.openbmc.control.Power";

using namespace phosphor::logging;
using namespace sdbusplus::xyz::openbmc_project::Power::Fault::Error;

bool PGOODMonitor::pgoodPending()
{
    bool pending = false;
    int32_t state = 0;
    int32_t pgood = 0;

    auto service = util::getService(POWER_OBJ_PATH,
            POWER_INTERFACE,
            bus);

    util::getProperty<int32_t>(POWER_INTERFACE,
            "pgood",
            POWER_OBJ_PATH,
            service,
            bus,
            pgood);

    //When state = 1, system was switched on
    util::getProperty<int32_t>(POWER_INTERFACE,
            "state",
            POWER_OBJ_PATH,
            service,
            bus,
            state);

    //On but no PGOOD
    if (state && !pgood)
    {
        pending = true;
    }

    return pending;
}


void PGOODMonitor::exitEventLoop()
{
    auto r = sd_event_exit(event.get(), EXIT_SUCCESS);
    if (r < 0)
    {
        log<level::ERR>("sd_event_exit failed",
                entry("RC = %d", r));
    }
}

void PGOODMonitor::analyze()
{
    //Timer callback.
    //The timer expired before it was stopped.
    //If PGOOD is still pending (it should be),
    //then there is a real failure.

    if (pgoodPending())
    {
        report<PowerOnFailure>();
    }

    //The pgood-wait service (with a longer timeout)
    //will handle powering off the system.

    exitEventLoop();
}

void PGOODMonitor::propertyChanged()
{
    //Multiple properties could have changed here.
    //Keep things simple and just recheck the important ones.
    if (!pgoodPending())
    {
        //PGOOD is on, or system is off, so we are done.
        timer.stop();
        exitEventLoop();
    }
}

void PGOODMonitor::startListening()
{
    match = std::make_unique<sdbusplus::bus::match_t>(
            bus,
            sdbusplus::bus::match::rules::propertiesChanged(
                POWER_OBJ_PATH,
                POWER_INTERFACE),
            [this](auto& msg){this->propertyChanged();});
}

int PGOODMonitor::run()
{
    try
    {
        startListening();

        //If PGOOD came up before we got here, we're done.
        //Otherwise if PGOOD doesn't get asserted before
        //the timer expires, it's a failure.
        if (!pgoodPending())
        {
            return EXIT_SUCCESS;
        }

        timer.start(interval);

        auto r = sd_event_loop(event.get());
        if (r < 0)
        {
            log<level::ERR>("sd_event_loop() failed",
                    entry("ERROR=%d", r));
        }
    }
    catch (std::exception& e)
    {
        log<level::ERR>(e.what());
        log<level::ERR>("Unexpected failure prevented PGOOD checking");
    }

    //Letting the service fail won't help anything, so don't do it.
    return EXIT_SUCCESS;
}


}
}