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 * Copyright (c) 1998-2014 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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 */

#include <IOKit/IOInterruptEventSource.h>
#include <IOKit/IOKitDebug.h>
#include <IOKit/IOLib.h>
#include <IOKit/IOService.h>
#include <IOKit/IOInterrupts.h>
#include <IOKit/IOTimeStamp.h>
#include <IOKit/IOWorkLoop.h>
#include <IOKit/IOInterruptAccountingPrivate.h>

#if IOKITSTATS

#define IOStatisticsInitializeCounter() \
do { \
	IOStatistics::setCounterType(IOEventSource::reserved->counter, kIOStatisticsInterruptEventSourceCounter); \
} while (0)

#define IOStatisticsCheckForWork() \
do { \
	IOStatistics::countInterruptCheckForWork(IOEventSource::reserved->counter); \
} while (0)

#define IOStatisticsInterrupt() \
do { \
	IOStatistics::countInterrupt(IOEventSource::reserved->counter); \
} while (0)

#else

#define IOStatisticsInitializeCounter()
#define IOStatisticsCheckForWork()
#define IOStatisticsInterrupt()

#endif // IOKITSTATS

#define super IOEventSource

OSDefineMetaClassAndStructors(IOInterruptEventSource, IOEventSource)
OSMetaClassDefineReservedUnused(IOInterruptEventSource, 0);
OSMetaClassDefineReservedUnused(IOInterruptEventSource, 1);
OSMetaClassDefineReservedUnused(IOInterruptEventSource, 2);
OSMetaClassDefineReservedUnused(IOInterruptEventSource, 3);
OSMetaClassDefineReservedUnused(IOInterruptEventSource, 4);
OSMetaClassDefineReservedUnused(IOInterruptEventSource, 5);
OSMetaClassDefineReservedUnused(IOInterruptEventSource, 6);
OSMetaClassDefineReservedUnused(IOInterruptEventSource, 7);

bool IOInterruptEventSource::init(OSObject *inOwner,
				  Action inAction,
				  IOService *inProvider,
				  int inIntIndex)
{
    bool res = true;

    if ( !super::init(inOwner, (IOEventSourceAction) inAction) )
        return false;

    reserved = IONew(ExpansionData, 1);

    if (!reserved) {
        return false;
    }

    bzero(reserved, sizeof(ExpansionData));

    provider = inProvider;
    producerCount = consumerCount = 0;
    autoDisable = explicitDisable = false;
    intIndex = ~inIntIndex;

    // Assumes inOwner holds a reference(retain) on the provider
    if (inProvider) {
        if (IA_ANY_STATISTICS_ENABLED) {
            /*
             * We only treat this as an "interrupt" if it has a provider; if it does,
             * set up the objects necessary to track interrupt statistics.  Interrupt
             * event sources without providers are most likely being used as simple
             * event source in order to poke at workloops and kick off work.
             *
             * We also avoid try to avoid interrupt accounting overhead if none of
             * the statistics are enabled.
             */
            reserved->statistics = IONew(IOInterruptAccountingData, 1);

            if (!reserved->statistics) {
                /*
                 * We rely on the free() routine to clean up after us if init fails
                 * midway.
                 */
                return false;
            }

            bzero(reserved->statistics, sizeof(IOInterruptAccountingData));

            reserved->statistics->owner = this;
        }

        res = (kIOReturnSuccess == registerInterruptHandler(inProvider, inIntIndex));

	if (res) {
	    intIndex = inIntIndex;
        }
    }

    IOStatisticsInitializeCounter();

    return res;
}

IOReturn IOInterruptEventSource::registerInterruptHandler(IOService *inProvider,
				  int inIntIndex)
{
    IOReturn ret;
    int intType;
    IOInterruptAction intHandler;

    ret = inProvider->getInterruptType(inIntIndex, &intType);
    if (kIOReturnSuccess != ret)
	return (ret);

    autoDisable = (intType == kIOInterruptTypeLevel);
    if (autoDisable) {
	intHandler = OSMemberFunctionCast(IOInterruptAction,
	    this, &IOInterruptEventSource::disableInterruptOccurred);
    }
    else
	intHandler = OSMemberFunctionCast(IOInterruptAction,
	    this, &IOInterruptEventSource::normalInterruptOccurred);

    ret = provider->registerInterrupt(inIntIndex, this, intHandler);

    /*
     * Add statistics to the provider.  The setWorkLoop convention should ensure
     * that we always go down the unregister path before we register (outside of
     * init()), so we don't have to worry that we will invoke addInterruptStatistics
     * erroneously.
     */
    if ((ret == kIOReturnSuccess) && (reserved->statistics)) {
        /*
         * Stash the normal index value, for the sake of debugging.
         */
        reserved->statistics->interruptIndex = inIntIndex;

        /*
         * We need to hook the interrupt information up to the provider so that it
         * can find the statistics for this interrupt when desired.  The provider is
         * responsible for maintaining the reporter for a particular interrupt, and
         * needs a handle on the statistics so that it can request that the reporter
         * be updated as needed.  Errors are considered "soft" for the moment (it
         * will either panic, or fail in a way such that we can still service the
         * interrupt).
         */
        provider->addInterruptStatistics(reserved->statistics, inIntIndex);

        /*
         * Add the statistics object to the global list of statistics objects; this
         * is an aid to debugging (we can trivially find statistics for all eligible
         * interrupts, and dump them; potentially helpful if the system is wedged
         * due to interrupt activity).
         */
        interruptAccountingDataAddToList(reserved->statistics);
    }

    return (ret);
}

void
IOInterruptEventSource::unregisterInterruptHandler(IOService *inProvider,
				  int inIntIndex)
{
    if (reserved->statistics) {
        interruptAccountingDataRemoveFromList(reserved->statistics);
        provider->removeInterruptStatistics(reserved->statistics->interruptIndex);
    }

    provider->unregisterInterrupt(inIntIndex);
}


IOInterruptEventSource *
IOInterruptEventSource::interruptEventSource(OSObject *inOwner,
					     Action inAction,
					     IOService *inProvider,
					     int inIntIndex)
{
    IOInterruptEventSource *me = new IOInterruptEventSource;

    if (me && !me->init(inOwner, inAction, inProvider, inIntIndex)) {
        me->release();
        return 0;
    }

    return me;
}

void IOInterruptEventSource::free()
{
    if (provider && intIndex >= 0)
        unregisterInterruptHandler(provider, intIndex);

    if (reserved) {
        if (reserved->statistics) {
            IODelete(reserved->statistics, IOInterruptAccountingData, 1);
        }

        IODelete(reserved, ExpansionData, 1);
    }

    super::free();
}

void IOInterruptEventSource::enable()
{
    if (provider && intIndex >= 0) {
        provider->enableInterrupt(intIndex);
        explicitDisable = false;
        enabled = true;
    }
}

void IOInterruptEventSource::disable()
{
    if (provider && intIndex >= 0) {
        provider->disableInterrupt(intIndex);
        explicitDisable = true;
        enabled = false;
    }
}

void IOInterruptEventSource::setWorkLoop(IOWorkLoop *inWorkLoop)
{
    if (inWorkLoop) super::setWorkLoop(inWorkLoop);

    if (provider) {
	if (!inWorkLoop) {
	    if (intIndex >= 0) {
                /*
                 * It isn't necessarily safe to wait until free() to unregister the interrupt;
                 * our provider may disappear.
                 */
                unregisterInterruptHandler(provider, intIndex);
		intIndex = ~intIndex;
	    }
	} else if ((intIndex < 0) && (kIOReturnSuccess == registerInterruptHandler(provider, ~intIndex))) {
	    intIndex = ~intIndex;
	}
    }

    if (!inWorkLoop) super::setWorkLoop(inWorkLoop);
}

const IOService *IOInterruptEventSource::getProvider() const
{
    return provider;
}

int IOInterruptEventSource::getIntIndex() const
{
    return intIndex;
}

bool IOInterruptEventSource::getAutoDisable() const
{
    return autoDisable;
}

bool IOInterruptEventSource::checkForWork()
{
    uint64_t startSystemTime = 0;
    uint64_t endSystemTime = 0;
    uint64_t startCPUTime = 0;
    uint64_t endCPUTime = 0;
    unsigned int cacheProdCount = producerCount;
    int numInts = cacheProdCount - consumerCount;
    IOInterruptEventAction intAction = (IOInterruptEventAction) action;
	bool trace = (gIOKitTrace & kIOTraceIntEventSource) ? true : false;
	
    IOStatisticsCheckForWork();
	
	if ( numInts > 0 )
	{
		if (trace)
			IOTimeStampStartConstant(IODBG_INTES(IOINTES_ACTION),
						 VM_KERNEL_UNSLIDE(intAction), (uintptr_t) owner, (uintptr_t) this, (uintptr_t) workLoop);

		if (reserved->statistics) {
			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelSystemTimeIndex)) {
				startSystemTime = mach_absolute_time();
			}

			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCPUTimeIndex)) {
				startCPUTime = thread_get_runtime_self();
			}
		}

		// Call the handler
		(*intAction)(owner, this, numInts);

		if (reserved->statistics) {
			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCountIndex)) {
				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelCountIndex], 1);
			}

			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCPUTimeIndex)) {
				endCPUTime = thread_get_runtime_self();
				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelCPUTimeIndex], endCPUTime - startCPUTime);
			}

			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelSystemTimeIndex)) {
				endSystemTime = mach_absolute_time();
				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelSystemTimeIndex], endSystemTime - startSystemTime);
			}
		}
		
		if (trace)
			IOTimeStampEndConstant(IODBG_INTES(IOINTES_ACTION),
					       VM_KERNEL_UNSLIDE(intAction), (uintptr_t) owner, (uintptr_t) this, (uintptr_t) workLoop);
		
		consumerCount = cacheProdCount;
		if (autoDisable && !explicitDisable)
			enable();
	}
	
	else if ( numInts < 0 )
	{
		if (trace)
			IOTimeStampStartConstant(IODBG_INTES(IOINTES_ACTION),
						 VM_KERNEL_UNSLIDE(intAction), (uintptr_t) owner, (uintptr_t) this, (uintptr_t) workLoop);

		if (reserved->statistics) {
			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelSystemTimeIndex)) {
				startSystemTime = mach_absolute_time();
			}

			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCPUTimeIndex)) {
				startCPUTime = thread_get_runtime_self();
			}
		}
		
		// Call the handler
		(*intAction)(owner, this, -numInts);

		if (reserved->statistics) {
			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCountIndex)) {
				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelCountIndex], 1);
			}

			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCPUTimeIndex)) {
				endCPUTime = thread_get_runtime_self();
				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelCPUTimeIndex], endCPUTime - startCPUTime);
			}

			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelSystemTimeIndex)) {
				endSystemTime = mach_absolute_time();
				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelSystemTimeIndex], endSystemTime - startSystemTime);
			}
		}
		
		if (trace)
			IOTimeStampEndConstant(IODBG_INTES(IOINTES_ACTION),
					       VM_KERNEL_UNSLIDE(intAction), (uintptr_t) owner, (uintptr_t) this, (uintptr_t) workLoop);
		
		consumerCount = cacheProdCount;
		if (autoDisable && !explicitDisable)
			enable();
	}
	
    return false;
}

void IOInterruptEventSource::normalInterruptOccurred
    (void */*refcon*/, IOService */*prov*/, int /*source*/)
{
	bool trace = (gIOKitTrace & kIOTraceIntEventSource) ? true : false;
	
    IOStatisticsInterrupt();
    producerCount++;
	
	if (trace)
	    IOTimeStampStartConstant(IODBG_INTES(IOINTES_SEMA), (uintptr_t) this, (uintptr_t) owner);

    if (reserved->statistics) {
        if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingFirstLevelCountIndex)) {
            IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingFirstLevelCountIndex], 1);
        }
    }
	
    signalWorkAvailable();
	
	if (trace)
	    IOTimeStampEndConstant(IODBG_INTES(IOINTES_SEMA), (uintptr_t) this, (uintptr_t) owner);
}

void IOInterruptEventSource::disableInterruptOccurred
    (void */*refcon*/, IOService *prov, int source)
{
	bool trace = (gIOKitTrace & kIOTraceIntEventSource) ? true : false;
	
    prov->disableInterrupt(source);	/* disable the interrupt */
	
    IOStatisticsInterrupt();
    producerCount++;
	
	if (trace)
	    IOTimeStampStartConstant(IODBG_INTES(IOINTES_SEMA), (uintptr_t) this, (uintptr_t) owner);

    if (reserved->statistics) {
        if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingFirstLevelCountIndex)) {
            IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingFirstLevelCountIndex], 1);
        }
    }
    
    signalWorkAvailable();
	
	if (trace)
	    IOTimeStampEndConstant(IODBG_INTES(IOINTES_SEMA), (uintptr_t) this, (uintptr_t) owner);
}

void IOInterruptEventSource::interruptOccurred
    (void *refcon, IOService *prov, int source)
{
    if (autoDisable && prov)
        disableInterruptOccurred(refcon, prov, source);
    else
        normalInterruptOccurred(refcon, prov, source);
}

IOReturn IOInterruptEventSource::warmCPU
    (uint64_t abstime)
{

	return ml_interrupt_prewarm(abstime);
}