/*
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * 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. 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,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
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 * @APPLE_LICENSE_HEADER_END@
 */

#include <libkern/OSByteOrder.h>

#include <IOKit/usb/IOUSBLog.h>

#include "AppleUSBOHCIMemoryBlocks.h"
#include "AppleUSBOHCI.h"

#define nil (0)
#define DEBUGGING_LEVEL 0	// 1 = low; 2 = high; 3 = extreme

#define super IOUSBController
#define self this


void AppleUSBOHCI::PollInterrupts(IOUSBCompletionAction safeAction)
{
    UInt64       	timeElapsed;
    
    // Calculate the time in nanoseconds between the last 2 calls to the filter interrupt routine.  Note that 
    // we lose the data if there was more than 1 filter routine called before our action routine was called.
    //
    absolutetime_to_nanoseconds(_filterTimeStamp2, &_timeElapsed); 

    // WritebackDoneHead Interrupt
    //
    if (_writeDoneHeadInterrupt & kOHCIHcInterrupt_WDH)
    {
        _writeDoneHeadInterrupt = 0;
        UIMProcessDoneQueue(safeAction);
    }

    // ResumeDetected Interrupt
    //
    if (_resumeDetectedInterrupt & kOHCIHcInterrupt_RD)
    {
        _resumeDetectedInterrupt = 0;

        //setPowerState(1, self);
        _remote_wakeup_occurred = true; //needed by ::callPlatformFunction()

        USBLog(3,"%s[%p] ResumeDetected Interrupt on bus %d", getName(), this, _busNumber );
        if ( _idleSuspend )
            setPowerState(kOHCISetPowerLevelRunning, self);
    }

    // Unrecoverable Error Interrupt
    //
    if (_unrecoverableErrorInterrupt & kOHCIHcInterrupt_UE)
    {
        _unrecoverableErrorInterrupt = 0;

        _errors.unrecoverableError++;
        // Let's do a SW reset to recover from this condition.
        // We could make sure all OCHI registers and in-memory
        // data structures are valid, too.
        _pOHCIRegisters->hcCommandStatus = USBToHostLong(kOHCIHcCommandStatus_HCR);
        delay(10 * MICROSECOND);

        // zzzz - note I'm leaving the Control/Bulk list processing off
        // for now.  FIXME? ERIC

        _pOHCIRegisters->hcControl = USBToHostLong((kOHCIFunctionalState_Operational << kOHCIHcControl_HCFSPhase) | kOHCIHcControl_PLE);
    }

    //	RootHubStatusChange Interrupt
    //
    if (_rootHubStatusChangeInterrupt & kOHCIHcInterrupt_RHSC)
    {
        
        _rootHubStatusChangeInterrupt = 0;
        _remote_wakeup_occurred = true; //needed by ::callPlatformFunction()

        USBLog(3,"%s[%p] RootHub Status Change Interrupt on bus %d", getName(), this, _busNumber );

        UIMRootHubStatusChange( false );
        LastRootHubPortStatusChanged ( true );

        // We let the RootHub driver enable this interrupt once it gets another interrupt read
        //
    }
}

void AppleUSBOHCI::InterruptHandler(OSObject *owner,
                                        IOInterruptEventSource * /*source*/,
                                        int /*count*/)
{
    register AppleUSBOHCI		*controller = (AppleUSBOHCI *) owner;

    if (!controller || controller->isInactive() || (controller->_onCardBus && controller->_pcCardEjected) || !controller->_ohciAvailable)
        return;

    // Finish pending transactions first.
    //
    controller->finishPending();
    controller->PollInterrupts();
    controller->_filterInterruptCount = 0;
    
}

// This routine will get called at Primary interrupt time.  When we are interrupted the host controller
// has already written the HCDoneHead register to the HCCADoneHeadRegister.  Furthermore, the host controller
// will NOT update the HCCADoneHeadRegister again until we clear the WDH (WritebackDoneHead) bit of the 
// HCInterruptStatus register.  At Filter Interrupt time (hardware interrupt) we will NOT clear that bit so that
// the Action Interrupt ( secondary interrupt) can fire and it will then clear the bit.
//
// At primary interrupt time we are only concerned with updating the frStatus and frActCount fields of the frames
// in low latency isoch TD's.  We will traverse the done queue (pointed by the HCCADoneHeadRegister) and look for those 
// TD and update the frStatus and frActCount fields just like is done in the ProcessCompletedITD routine.
//
// The Done Queue has physical addresses.  We need to traverse the queue using logical addresses, so we need to do
// a lookup of the logical address from the physical address. 
//
bool 
AppleUSBOHCI::PrimaryInterruptFilter(OSObject *owner, IOFilterInterruptEventSource *source)
{
    register AppleUSBOHCI *controller = (AppleUSBOHCI *)owner;
    bool result = true;

    // If we our controller has gone away, or it's going away, or if we're on a PC Card and we have been ejected,
    // then don't process this interrupt.
    //
    if (!controller || controller->isInactive() || (controller->_onCardBus && controller->_pcCardEjected) || !controller->_ohciAvailable)
        return false;
    
    // Process this interrupt
    //
    result = controller->FilterInterrupt(0);
    return result;
}


//================================================================================================
//
//  IsValidPhysicalAddress()
//
//  This routine will search for the incoming physical address in our GTD and ITD Memory Blocks.  This
//  is used to verify that the address is one that we "know" about before we actually try to read from
//  it to get the logical address (that is stored at the beginning of the memory blocks).
//
//  Note that the comparison is making use of the fact that we allocate our memory blocks in kOHCIPageSize
//  chunks, so we only need to compare the page #'s to see if they are equal.  We are assuming that the
//  incoming address is the address of an OHCI page (lower 12 bits are 0).
//
//================================================================================================
//
bool
AppleUSBOHCI::IsValidPhysicalAddress(IOPhysicalAddress pageAddr)
{
    AppleUSBOHCIitdMemoryBlock 	*itdMemBlock = _itdMBHead;
    AppleUSBOHCIgtdMemoryBlock 	*gtdMemBlock = _gtdMBHead;

    while (gtdMemBlock)
    {
        if ( pageAddr == (gtdMemBlock->GetSharedPhysicalPtr(0) & kOHCIPageMask) )
            return true;
        gtdMemBlock = gtdMemBlock->GetNextBlock();
    }

    while (itdMemBlock)
    {
        if ( pageAddr == (itdMemBlock->GetSharedPhysicalPtr(0) & kOHCIPageMask) )
            return true;
        itdMemBlock = itdMemBlock->GetNextBlock();
    }
    return false;
}


bool 
AppleUSBOHCI::FilterInterrupt(int index)
{
    
    register UInt32				activeInterrupts;
    register UInt32				enabledInterrupts;
    IOPhysicalAddress				physicalAddress;
    AppleOHCIGeneralTransferDescriptorPtr 	pHCDoneTD = NULL;
    AppleOHCIGeneralTransferDescriptorPtr	nextTD = NULL, prevTD = NULL;
    AbsoluteTime				timeStamp;
    UInt32					numberOfTDs = 0;
    IOPhysicalAddress				oldHead;
    IOPhysicalAddress				cachedHead;
    UInt32					cachedProducer;
    Boolean					needSecondary = false;
    

    // Check if the OHCI has written the DoneHead yet.  First we get the list of
    // active enabled interrupts and we make sure that the master interrupts bit
    // is enabled and that we do have an interrupt to process. 
    //
    enabledInterrupts = USBToHostLong(_pOHCIRegisters->hcInterruptEnable);
    activeInterrupts = enabledInterrupts & USBToHostLong(_pOHCIRegisters->hcInterruptStatus);

    if ((enabledInterrupts & kOHCIHcInterrupt_MIE) && (activeInterrupts != 0))
    {
        
        // One of our 8 interrupts fired.  Need to see which one it is
        //

        // Frame Number Overflow
        //
        if (activeInterrupts & kOHCIHcInterrupt_FNO)
        {
            // not really an error, but close enough
            //
            _errors.frameNumberOverflow++;
            
            if ( (USBToHostWord(*(UInt16*)(_pHCCA + kHCCAFrameNumberOffset)) & kOHCIFmNumberMask) < kOHCIBit15 )
		_frameNumber += kOHCIFrameOverflowBit;
            
            // Clear the interrupt
            //
            _pOHCIRegisters->hcInterruptStatus = HostToUSBLong(kOHCIHcInterrupt_FNO);
            IOSync();
        }
        
        // SchedulingOverrun Interrupt
        //
        if (activeInterrupts & kOHCIHcInterrupt_SO)
        {
            _errors.scheduleOverrun++;
            
            // Clear the interrupt
            //
            _pOHCIRegisters->hcInterruptStatus = HostToUSBLong(kOHCIHcInterrupt_SO);
            IOSync();
        }

        // StartofFrame Interrupt
        //
        if (activeInterrupts & kOHCIHcInterrupt_SF)
        {
            // Clear the interrrupt
            //
            _pOHCIRegisters->hcInterruptStatus = HostToUSBLong(kOHCIHcInterrupt_SF);
            IOSync();

            // and mask it off so it doesn't happen again.
            // will have to be turned on manually to happen again.
            //
            _pOHCIRegisters->hcInterruptDisable = HostToUSBLong(kOHCIHcInterrupt_SF);
            IOSync();

        }

        // OwnershipChange Interrupt
        //
        if (activeInterrupts & kOHCIHcInterrupt_OC)
        {
            // well, we certainly weren't expecting this!
            _errors.ownershipChange++;
            
            // Clear the interrupt
            //
            _pOHCIRegisters->hcInterruptStatus = HostToUSBLong(kOHCIHcInterrupt_OC);
            IOSync();

        }

        // RootHub Status Change Interrupt
        //
        if (activeInterrupts & kOHCIHcInterrupt_RHSC)
        {
            // Set the shadow field that will tell the secondary interrput that we had an RHSC
            // Interrupt event
            //
            _rootHubStatusChangeInterrupt = kOHCIHcInterrupt_RHSC;
            
	    // disable the RHSC interrupt until we process it at secondary interrupt
	    // time. some controllers do not respond to the clear bit
            _pOHCIRegisters->hcInterruptDisable = HostToUSBLong(kOHCIHcInterrupt_RHSC);
            IOSync();

            // Clear the interrupt
            //
            _pOHCIRegisters->hcInterruptStatus = HostToUSBLong(kOHCIHcInterrupt_RHSC);
            IOSync();
	    needSecondary = true;
        }

        // Unrecoverable Error Interrupt
        //
        if (activeInterrupts & kOHCIHcInterrupt_UE)
        {
            _errors.unrecoverableError++;

            // Set the shadow field that will tell the secondary interrput that we had an RHSC
            // Interrupt event
            //
            _unrecoverableErrorInterrupt = kOHCIHcInterrupt_UE;
            
            // Clear the interrupt
            //
            _pOHCIRegisters->hcInterruptStatus = HostToUSBLong(kOHCIHcInterrupt_UE);
            IOSync();
	    needSecondary = true;
        }

        // Resume Detected Interrupt
        //
        if (activeInterrupts & kOHCIHcInterrupt_RD)
        {
            // Set the shadow field that will tell the secondary interrput that we had an RD
            // Interrupt event
            //
            _resumeDetectedInterrupt = kOHCIHcInterrupt_RD;
            
            // Clear the interrupt
            //
            _pOHCIRegisters->hcInterruptStatus = HostToUSBLong(kOHCIHcInterrupt_RD);
            IOSync();
	    needSecondary = true;
        }

        // Check to see if the WriteDoneHead interrupt fired.  If so, then we can look at the queue
        //
        if (activeInterrupts & kOHCIHcInterrupt_WDH)
        {
            // Now that we have the beginning of the queue, walk it looking for low latency isoch TD's
            // Use this time as the time stamp time for all the TD's that we processed.  
            //
            clock_get_uptime(&timeStamp);
            
            // Debugging aid to keep track of how long we take in between calls to the filter routine
            //
            _filterInterruptCount++;
            
            _filterTimeStamp2 = timeStamp;
            SUB_ABSOLUTETIME(&_filterTimeStamp2, &_filterTimeStamp); 
            _filterTimeStamp = timeStamp;


           // Get the pointer to the list (physical address)
            //
            physicalAddress = (UInt32) USBToHostLong(*(UInt32 *)(_pHCCA + kHCCADoneHeadOffset));
            
            // Mask off interrupt bits
            //
            physicalAddress &= kOHCIHeadPMask;
            
            // Save the current value of the shadow queue head so that we can link our new head
            // to it later on.
            //
            oldHead = _savedDoneQueueHead; 
            
            // And save the current head
            //
            cachedHead = physicalAddress;

            if ( physicalAddress == NULL )
                pHCDoneTD = NULL;
            else
            {
                if ( _onCardBus )
                {
                    if (!IsValidPhysicalAddress( physicalAddress & kOHCIPageMask) )
                    {
                        USBLog(1, "Bad phys addr #1 %p", physicalAddress);
                        pHCDoneTD = NULL;
                    }
                    else
                    {
                        pHCDoneTD = AppleUSBOHCIgtdMemoryBlock::GetGTDFromPhysical(physicalAddress);
                    }
                }
                else
                {
                    // Now get the logical address from the physical one
                    //
                    pHCDoneTD = AppleUSBOHCIgtdMemoryBlock::GetGTDFromPhysical(physicalAddress);
                }
            }


            // write to 0 to the HCCA DoneHead ptr so we won't look at it anymore.
            //
            *(UInt32 *)(_pHCCA + kHCCADoneHeadOffset) = 0L;
        
            // Since we have a copy of the queue to process, we can let the host update it again.  We 
            // do this by writing one to the bit in the register.
            //
            _pOHCIRegisters->hcInterruptStatus = HostToUSBLong(kOHCIHcInterrupt_WDH);
            IOSync();
            
            _writeDoneHeadInterrupt = kOHCIHcInterrupt_WDH;
            
            prevTD = NULL;
            
            while (pHCDoneTD != NULL)
            {
                AppleOHCIIsochTransferDescriptorPtr	pITD;
                IOUSBLowLatencyIsocFrame *		pFrames;
                IOReturn 				errStatus;
                UInt32					control;
                UInt32					transferStatus;
                UInt32					frameCount;
                UInt32					i;
                
                // Increment our count of the number of TDs that this queue head is pointing to
                //
                numberOfTDs++;

                // Find the next one
                //
                physicalAddress = USBToHostLong(pHCDoneTD->pShared->nextTD) & kOHCIHeadPMask;

                if ( physicalAddress == NULL )
                    nextTD = NULL;
                else
                {
                    if ( _onCardBus )
                    {
                        if (!IsValidPhysicalAddress( physicalAddress & kOHCIPageMask) )
                        {
                            nextTD = NULL;
                        }
                        else
                            nextTD = AppleUSBOHCIgtdMemoryBlock::GetGTDFromPhysical(physicalAddress);
                    }
                    else
                        nextTD = AppleUSBOHCIgtdMemoryBlock::GetGTDFromPhysical(physicalAddress);
                }
                
                if ( (pHCDoneTD->pType == kOHCIIsochronousInLowLatencyType) || 
                    (pHCDoneTD->pType == kOHCIIsochronousOutLowLatencyType) )
                {
                    // We have a low latency isoch TD.  Update debugging stamps
                    //
                    _lowLatencyIsochTDsProcessed++;
                    
                    // Since we know it's an ITD, cast it into one and get a pointer to the Low Latency ITD's frames
                    //
                    pITD = (AppleOHCIIsochTransferDescriptorPtr) pHCDoneTD;
                    pFrames = (IOUSBLowLatencyIsocFrame *) pITD->pIsocFrame;
                    
                    // Get any errors from the TD
                    //
                    control = USBToHostLong(pHCDoneTD->pShared->ohciFlags);
                    transferStatus = (control & kOHCIGTDControl_CC) >> kOHCIGTDControl_CCPhase;
                    errStatus = TranslateStatusToUSBError(transferStatus);
            
                    // Process the frames in the low latency isochTDs
                    //
                    frameCount = (USBToHostLong(pITD->pShared->flags) & kOHCIITDControl_FC) >> kOHCIITDControl_FCPhase;
                    for (i = 0; i <= frameCount; i++)
                    {
                        // Debugging stamps
                        //
                        _framesUpdated++;
                        if ( pFrames[pITD->frameNum + i].frStatus != (IOReturn) kUSBLowLatencyIsochTransferKey )
                            _framesError++;
                        
                        // Set the time stamp
                        //
                        pFrames[pITD->frameNum + i].frTimeStamp = timeStamp;
                        
                        // Get information on whether there was an error in the frame
                        //
                        UInt16 offset = USBToHostWord(pITD->pShared->offset[i]);
                        
                        if ( ((offset & kOHCIITDOffset_CC) >> kOHCIITDOffset_CCPhase) == kOHCIITDOffsetConditionNotAccessed)
                        {
                            // If the condition code is not accessed, set the frActCount to 0 and the status accordingly
                            //
                            pFrames[pITD->frameNum + i].frActCount = 0;
                            pFrames[pITD->frameNum + i].frStatus = TranslateStatusToUSBError(kOHCIITDConditionNotAccessedReturn);
                        }
                        else
                        {
                             // Set the frStatus to the OHCI Condition code translated to the correct USB Error
                            //
                            pFrames[pITD->frameNum + i].frStatus = TranslateStatusToUSBError( (offset & kOHCIITDPSW_CC) >> kOHCIITDPSW_CCPhase);
                            
                            // Successful isoch transmit sets the size field to requested count,
                            // successful receive sets size to actual packet size received
                            //
                            if((kIOReturnSuccess == pFrames[pITD->frameNum + i].frStatus) && (pITD->pType == kOHCIIsochronousOutLowLatencyType))
                                pFrames[pITD->frameNum + i].frActCount = pFrames[pITD->frameNum + i].frReqCount;
                            else
                                pFrames[pITD->frameNum + i].frActCount = offset & kOHCIITDPSW_Size;
                        }
                        
                    }
                }
                
                prevTD = pHCDoneTD;
                
                // Look at the next TD
                pHCDoneTD = nextTD;	/* New qHead */
            }
            
            // We have now processed all the TD's in this queue.  We need to update our producer count
            //
            cachedProducer = _producerCount;
            cachedProducer += numberOfTDs;
                            
            // Now link in to the old queue head.  Note that we have to write this in bus order as the
            // secondary interrupt routine will do the opposite when it reverses the list
            //
            if ( prevTD != NULL )
                prevTD->pShared->nextTD = HostToUSBLong(oldHead);
            
            // Now, update the producer and head. We need to take a lock so that the consumer (the action routine) does not read them
            // while they are in transition.
            //
            IOSimpleLockLock( _wdhLock );
            
            _savedDoneQueueHead = cachedHead;	// updates the shadow head
            _producerCount = cachedProducer;	// Validates _producerCount;
            
            IOSimpleLockUnlock( _wdhLock );
	    needSecondary = true;
        }
    }

    
    // We will return false from this filter routine, but will indicate that there the action routine should be called by calling _filterInterruptSource->signalInterrupt(). 
    // This is needed because IOKit will disable interrupts for a level interrupt after the filter interrupt is run, until the action interrupt is called.  We want to be
    // able to have our filter interrupt routine called before the action routine runs, if needed.  That is what will enable low latency isoch transfers to work, as when the
    // system is under heavy load, the action routine can be delayed for tens of ms.
    //
    if (needSecondary)
	_filterInterruptSource->signalInterrupt();
    
    return false;
    
}
