os/kernelhwsrv/kernel/eka/drivers/dma/dmapil.cpp
changeset 0 bde4ae8d615e
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/os/kernelhwsrv/kernel/eka/drivers/dma/dmapil.cpp	Fri Jun 15 03:10:57 2012 +0200
     1.3 @@ -0,0 +1,1102 @@
     1.4 +// Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
     1.5 +// All rights reserved.
     1.6 +// This component and the accompanying materials are made available
     1.7 +// under the terms of the License "Eclipse Public License v1.0"
     1.8 +// which accompanies this distribution, and is available
     1.9 +// at the URL "http://www.eclipse.org/legal/epl-v10.html".
    1.10 +//
    1.11 +// Initial Contributors:
    1.12 +// Nokia Corporation - initial contribution.
    1.13 +//
    1.14 +// Contributors:
    1.15 +//
    1.16 +// Description:
    1.17 +// e32\drivers\dmapil.cpp
    1.18 +// DMA Platform Independent Layer (PIL)
    1.19 +// 
    1.20 +//
    1.21 +
    1.22 +#include <drivers/dma.h>
    1.23 +#include <kernel/kern_priv.h>
    1.24 +
    1.25 +
    1.26 +static const char KDmaPanicCat[] = "DMA";
    1.27 +
    1.28 +NFastMutex DmaChannelMgr::Lock;
    1.29 +
    1.30 +class TDmaCancelInfo : public SDblQueLink
    1.31 +	{
    1.32 +public:
    1.33 +	TDmaCancelInfo();
    1.34 +	void Signal();
    1.35 +public:
    1.36 +	NFastSemaphore iSem;
    1.37 +	};
    1.38 +
    1.39 +TDmaCancelInfo::TDmaCancelInfo()
    1.40 +	:	iSem(0)
    1.41 +	{
    1.42 +	iNext = this;
    1.43 +	iPrev = this;
    1.44 +	}
    1.45 +
    1.46 +void TDmaCancelInfo::Signal()
    1.47 +	{
    1.48 +	TDmaCancelInfo* p = this;
    1.49 +	FOREVER
    1.50 +		{
    1.51 +		TDmaCancelInfo* next = (TDmaCancelInfo*)p->iNext;
    1.52 +		if (p!=next)
    1.53 +			p->Deque();
    1.54 +		NKern::FSSignal(&p->iSem);	// Don't dereference p after this
    1.55 +		if (p==next)
    1.56 +			break;
    1.57 +		p = next;
    1.58 +		}
    1.59 +	}
    1.60 +
    1.61 +//////////////////////////////////////////////////////////////////////////////
    1.62 +
    1.63 +#ifdef __DMASIM__
    1.64 +#ifdef __WINS__
    1.65 +typedef TLinAddr TPhysAddr;
    1.66 +#endif
    1.67 +static inline TPhysAddr LinToPhys(TLinAddr aLin) {return aLin;}
    1.68 +#else
    1.69 +static inline TPhysAddr LinToPhys(TLinAddr aLin) {return Epoc::LinearToPhysical(aLin);}
    1.70 +#endif
    1.71 +
    1.72 +//
    1.73 +// Return minimum of aMaxSize and size of largest physically contiguous block
    1.74 +// starting at aLinAddr.
    1.75 +//
    1.76 +static TInt MaxPhysSize(TLinAddr aLinAddr, const TInt aMaxSize)
    1.77 +	{
    1.78 +	const TPhysAddr physBase = LinToPhys(aLinAddr);
    1.79 +	TLinAddr lin = aLinAddr;
    1.80 +	TInt size = 0;
    1.81 +	for (;;)
    1.82 +		{
    1.83 +		// Round up the linear address to the next MMU page boundary
    1.84 +		const TLinAddr linBoundary = Kern::RoundToPageSize(lin + 1);
    1.85 +		size += linBoundary - lin;
    1.86 +		if (size >= aMaxSize)
    1.87 +			return aMaxSize;
    1.88 +		if ((physBase + size) != LinToPhys(linBoundary))
    1.89 +			return size;
    1.90 +		lin = linBoundary;
    1.91 +		}
    1.92 +	}
    1.93 +
    1.94 +
    1.95 +//////////////////////////////////////////////////////////////////////////////
    1.96 +// TDmac
    1.97 +
    1.98 +TDmac::TDmac(const SCreateInfo& aInfo)
    1.99 +	: iMaxDesCount(aInfo.iDesCount),
   1.100 +	  iAvailDesCount(aInfo.iDesCount),
   1.101 +	  iDesSize(aInfo.iDesSize),
   1.102 +	  iCaps(aInfo.iCaps)
   1.103 +	{
   1.104 +	__DMA_ASSERTD(iMaxDesCount > 0);
   1.105 +	__DMA_ASSERTD((iCaps & ~KCapsBitHwDes) == 0); // undefined bits set?
   1.106 +	__DMA_ASSERTD(iDesSize > 0);
   1.107 +	}
   1.108 +
   1.109 +//
   1.110 +// Second-phase c'tor
   1.111 +//
   1.112 +
   1.113 +TInt TDmac::Create(const SCreateInfo& aInfo)
   1.114 +	{
   1.115 +	iHdrPool = new SDmaDesHdr[iMaxDesCount];
   1.116 +	if (iHdrPool == NULL)
   1.117 +		return KErrNoMemory;
   1.118 +
   1.119 +	TInt r = AllocDesPool(aInfo.iDesChunkAttribs);
   1.120 +	if (r != KErrNone)
   1.121 +		return KErrNoMemory;
   1.122 +
   1.123 +	// Link all descriptor headers together on the free list
   1.124 +	iFreeHdr = iHdrPool;
   1.125 +	TInt i;
   1.126 +	for (i = 0; i < iMaxDesCount - 1; i++)
   1.127 +		iHdrPool[i].iNext = iHdrPool + i + 1;
   1.128 +	iHdrPool[iMaxDesCount-1].iNext = NULL;
   1.129 +
   1.130 +	__DMA_INVARIANT();
   1.131 +	return KErrNone;
   1.132 +	}
   1.133 +
   1.134 +
   1.135 +TDmac::~TDmac()
   1.136 +	{
   1.137 +	__DMA_INVARIANT();
   1.138 +
   1.139 +	FreeDesPool();
   1.140 +	delete[] iHdrPool;
   1.141 +	}
   1.142 +
   1.143 +
   1.144 +// Calling thread must be in CS
   1.145 +TInt TDmac::AllocDesPool(TUint aAttribs)
   1.146 +	{
   1.147 +	TInt r;
   1.148 +	if (iCaps & KCapsBitHwDes)
   1.149 +		{
   1.150 +		TInt size = iMaxDesCount*iDesSize;
   1.151 +#ifdef __WINS__
   1.152 +		(void)aAttribs;
   1.153 +		iDesPool = new TUint8[size];
   1.154 +		r = iDesPool ? KErrNone : KErrNoMemory;
   1.155 +#else
   1.156 +		// Chunk not mapped as supervisor r/w user none? incorrect mask passed by PSL
   1.157 +		__DMA_ASSERTD((aAttribs & EMapAttrAccessMask) == EMapAttrSupRw);
   1.158 +		TPhysAddr phys;
   1.159 +		r = Epoc::AllocPhysicalRam(size, phys);
   1.160 +		if (r == KErrNone)
   1.161 +			{
   1.162 +			r = DPlatChunkHw::New(iHwDesChunk, phys, size, aAttribs);
   1.163 +			if (r == KErrNone)
   1.164 +				{
   1.165 +				iDesPool = (TAny*)iHwDesChunk->LinearAddress();
   1.166 +				__KTRACE_OPT(KDMA, Kern::Printf("descriptor hw chunk created lin=0x%08X phys=0x%08X, size=0x%X",
   1.167 +												iHwDesChunk->iLinAddr, iHwDesChunk->iPhysAddr, size));
   1.168 +				}
   1.169 +			else
   1.170 +				Epoc::FreePhysicalRam(phys, size);
   1.171 +			}
   1.172 +#endif
   1.173 +		}
   1.174 +	else
   1.175 +		{
   1.176 +		iDesPool = new SDmaPseudoDes[iMaxDesCount];
   1.177 +		r = iDesPool ? KErrNone : KErrNoMemory;
   1.178 +		}
   1.179 +	return r;
   1.180 +	}
   1.181 +
   1.182 +
   1.183 +// Calling thread must be in CS
   1.184 +void TDmac::FreeDesPool()
   1.185 +	{
   1.186 +	if (iCaps & KCapsBitHwDes)
   1.187 +		{
   1.188 +#ifdef __WINS__
   1.189 +		delete[] iDesPool;
   1.190 +#else
   1.191 +		if (iHwDesChunk)
   1.192 +			{
   1.193 +			TPhysAddr phys = iHwDesChunk->PhysicalAddress();
   1.194 +			TInt size = iHwDesChunk->iSize;
   1.195 +			iHwDesChunk->Close(NULL);
   1.196 +			Epoc::FreePhysicalRam(phys, size);
   1.197 +			}
   1.198 +#endif
   1.199 +		}
   1.200 +	else
   1.201 +		Kern::Free(iDesPool); 
   1.202 +	}
   1.203 +
   1.204 +
   1.205 +/**
   1.206 + Prealloc the given number of descriptors.
   1.207 + */
   1.208 +
   1.209 +TInt TDmac::ReserveSetOfDes(TInt aCount)
   1.210 +	{
   1.211 +	__KTRACE_OPT(KDMA, Kern::Printf(">TDmac::ReserveSetOfDes count=%d", aCount));
   1.212 +	__DMA_ASSERTD(aCount > 0);
   1.213 +	TInt r = KErrTooBig;
   1.214 +	Wait();
   1.215 +	if (iAvailDesCount - aCount >= 0)
   1.216 +		{
   1.217 +		iAvailDesCount -= aCount;
   1.218 +		r = KErrNone;
   1.219 +		}
   1.220 +	Signal();
   1.221 +	__DMA_INVARIANT();
   1.222 +	__KTRACE_OPT(KDMA, Kern::Printf("<TDmac::ReserveSetOfDes r=%d", r));
   1.223 +	return r;
   1.224 +	}
   1.225 +
   1.226 +
   1.227 +/**
   1.228 + Return the given number of preallocated descriptors to the free pool.
   1.229 + */
   1.230 +
   1.231 +void TDmac::ReleaseSetOfDes(TInt aCount)
   1.232 +	{
   1.233 +	__DMA_ASSERTD(aCount >= 0);
   1.234 +	Wait();
   1.235 +	iAvailDesCount += aCount;
   1.236 +	Signal();
   1.237 +	__DMA_INVARIANT();
   1.238 +	}
   1.239 +
   1.240 +
   1.241 +/**
   1.242 + Queue DFC and update word used to communicate with DFC.
   1.243 +
   1.244 + Called in interrupt context by PSL.
   1.245 + */
   1.246 +
   1.247 +void TDmac::HandleIsr(TDmaChannel& aChannel, TBool aIsComplete)
   1.248 +	{
   1.249 +	//__KTRACE_OPT(KDMA, Kern::Printf("TDmac::HandleIsr channel=%d complete=%d", aChannelIdx, aIsComplete));
   1.250 +
   1.251 +	// Queue DFC if necessary.  The possible scenarios are:
   1.252 +	// * no DFC queued --> need to queue DFC
   1.253 +	// * DFC queued (not running yet) --> just need to update iIsrDfc
   1.254 +	// * DFC running / iIsrDfc already reset --> need to requeue DFC
   1.255 +	// * DFC running /  iIsrDfc not reset yet --> just need to update iIsrDfc
   1.256 +	// Set error flag if necessary.
   1.257 +	TUint32 inc = aIsComplete ? 1u : TUint32(TDmaChannel::KErrorFlagMask)|1u;
   1.258 +	TUint32 orig = __e32_atomic_tau_ord32(&aChannel.iIsrDfc, TUint32(TDmaChannel::KCancelFlagMask), 0, inc);
   1.259 +
   1.260 +	// As transfer should be suspended when an error occurs, we
   1.261 +	// should never get there with the error flag already set.
   1.262 +	__DMA_ASSERTD((orig & inc & (TUint32)TDmaChannel::KErrorFlagMask) == 0);
   1.263 +
   1.264 +	if (orig == 0)
   1.265 +		aChannel.iDfc.Add();
   1.266 +	}
   1.267 +
   1.268 +
   1.269 +void TDmac::InitDes(const SDmaDesHdr& aHdr, TUint32 aSrc, TUint32 aDest, TInt aCount,
   1.270 +					TUint aFlags, TUint32 aPslInfo, TUint32 aCookie)
   1.271 +	{
   1.272 + 	if (iCaps & KCapsBitHwDes)
   1.273 +		InitHwDes(aHdr, aSrc, aDest, aCount, aFlags, aPslInfo, aCookie);
   1.274 +	else
   1.275 +		{
   1.276 +		SDmaPseudoDes& des = HdrToDes(aHdr);
   1.277 +		des.iSrc = aSrc;
   1.278 +		des.iDest = aDest;
   1.279 +		des.iCount = aCount;
   1.280 +		des.iFlags = aFlags;
   1.281 +		des.iPslInfo = aPslInfo;
   1.282 +		des.iCookie = aCookie;
   1.283 +		}
   1.284 +	}
   1.285 +
   1.286 +
   1.287 +void TDmac::InitHwDes(const SDmaDesHdr& /*aHdr*/, TUint32 /*aSrc*/, TUint32 /*aDest*/, TInt /*aCount*/,
   1.288 +					  TUint /*aFlags*/, TUint32 /*aPslInfo*/, TUint32 /*aCookie*/)
   1.289 +	{
   1.290 +	// concrete controller must override if KCapsBitHwDes set
   1.291 +	__DMA_CANT_HAPPEN();
   1.292 +	}
   1.293 +
   1.294 +
   1.295 +void TDmac::ChainHwDes(const SDmaDesHdr& /*aHdr*/, const SDmaDesHdr& /*aNextHdr*/)
   1.296 +	{
   1.297 +	// concrete controller must override if KCapsBitHwDes set
   1.298 +	__DMA_CANT_HAPPEN();
   1.299 +	}
   1.300 +
   1.301 +
   1.302 +void TDmac::AppendHwDes(const TDmaChannel& /*aChannel*/, const SDmaDesHdr& /*aLastHdr*/,
   1.303 +						const SDmaDesHdr& /*aNewHdr*/)
   1.304 +	{
   1.305 + 	// concrete controller must override if KCapsBitHwDes set
   1.306 +	__DMA_CANT_HAPPEN();
   1.307 +	}
   1.308 +
   1.309 +
   1.310 +void TDmac::UnlinkHwDes(const TDmaChannel& /*aChannel*/, SDmaDesHdr& /*aHdr*/)
   1.311 +	{
   1.312 + 	// concrete controller must override if KCapsBitHwDes set
   1.313 +	__DMA_CANT_HAPPEN();
   1.314 +	}
   1.315 +
   1.316 +
   1.317 +TInt TDmac::FailNext(const TDmaChannel& /*aChannel*/)
   1.318 +	{
   1.319 +	return KErrNotSupported;
   1.320 +	}
   1.321 +
   1.322 +
   1.323 +TInt TDmac::MissNextInterrupts(const TDmaChannel& /*aChannel*/, TInt /*aInterruptCount*/)
   1.324 +	{
   1.325 +	return KErrNotSupported;
   1.326 +	}
   1.327 +
   1.328 +
   1.329 +TInt TDmac::Extension(TDmaChannel& /*aChannel*/, TInt /*aCmd*/, TAny* /*aArg*/)
   1.330 +	{
   1.331 +	// default implementation - NOP
   1.332 +	return KErrNotSupported;
   1.333 +	}
   1.334 +
   1.335 +
   1.336 +#ifdef _DEBUG
   1.337 +
   1.338 +void TDmac::Invariant()
   1.339 +	{
   1.340 +	Wait();
   1.341 +	__DMA_ASSERTD(0 <= iAvailDesCount && iAvailDesCount <= iMaxDesCount);
   1.342 +	__DMA_ASSERTD(! iFreeHdr || IsValidHdr(iFreeHdr));
   1.343 +	for (TInt i = 0; i < iMaxDesCount; i++)
   1.344 +		__DMA_ASSERTD(iHdrPool[i].iNext == NULL || IsValidHdr(iHdrPool[i].iNext));
   1.345 +	Signal();
   1.346 +	}
   1.347 +
   1.348 +
   1.349 +TBool TDmac::IsValidHdr(const SDmaDesHdr* aHdr)
   1.350 +	{
   1.351 +	return (iHdrPool <= aHdr) && (aHdr < iHdrPool + iMaxDesCount);
   1.352 +	}
   1.353 +
   1.354 +#endif
   1.355 +
   1.356 +//////////////////////////////////////////////////////////////////////////////
   1.357 +// DDmaRequest
   1.358 +
   1.359 +
   1.360 +EXPORT_C DDmaRequest::DDmaRequest(TDmaChannel& aChannel, TCallback aCb, TAny* aCbArg, TInt aMaxTransferSize)
   1.361 +	: iChannel(aChannel),
   1.362 +	  iCb(aCb),
   1.363 +	  iCbArg(aCbArg),
   1.364 +	  iMaxTransferSize(aMaxTransferSize)
   1.365 +	{
   1.366 +	// iDesCount = 0;
   1.367 +	// iFirstHdr = iLastHdr = NULL;
   1.368 +	// iQueued = EFalse;
   1.369 +	iChannel.iReqCount++;
   1.370 +	__DMA_INVARIANT();
   1.371 +	}
   1.372 +
   1.373 +
   1.374 +
   1.375 +EXPORT_C DDmaRequest::~DDmaRequest()
   1.376 +	{
   1.377 +	__DMA_ASSERTD(!iQueued);
   1.378 +	__DMA_INVARIANT();
   1.379 +	FreeDesList();
   1.380 +	iChannel.iReqCount--;
   1.381 +	}
   1.382 +
   1.383 +
   1.384 +
   1.385 +EXPORT_C TInt DDmaRequest::Fragment(TUint32 aSrc, TUint32 aDest, TInt aCount, TUint aFlags, TUint32 aPslInfo)
   1.386 +	{
   1.387 +	__KTRACE_OPT(KDMA, Kern::Printf("DDmaRequest::Fragment thread %O "
   1.388 +									"src=0x%08X dest=0x%08X count=%d flags=0x%X psl=0x%08X",
   1.389 +									&Kern::CurrentThread(), aSrc, aDest, aCount, aFlags, aPslInfo));
   1.390 +	__DMA_ASSERTD(aCount > 0);
   1.391 +	__DMA_ASSERTD(!iQueued);
   1.392 +
   1.393 +	const TUint alignMask = iChannel.MemAlignMask(aFlags, aPslInfo);
   1.394 +	const TBool memSrc  = aFlags & KDmaMemSrc;
   1.395 +	const TBool memDest = aFlags & KDmaMemDest;
   1.396 +
   1.397 +	// Memory buffers must satisfy alignment constraint
   1.398 +	__DMA_ASSERTD(!memSrc || ((aSrc & alignMask) == 0));
   1.399 +	__DMA_ASSERTD(!memDest || ((aDest & alignMask) == 0));
   1.400 +
   1.401 +	// Ask the PSL what the maximum size possible for this transfer is
   1.402 +	TInt maxTransferSize = iChannel.MaxTransferSize(aFlags, aPslInfo);
   1.403 +	if (!maxTransferSize)
   1.404 +		{
   1.405 +		__KTRACE_OPT(KPANIC, Kern::Printf("Error: maxTransferSize == 0"));
   1.406 +		return KErrArgument;
   1.407 +		}
   1.408 +
   1.409 +	if (iMaxTransferSize)
   1.410 +		{
   1.411 +		// User has set a size cap
   1.412 +		__DMA_ASSERTA((iMaxTransferSize <= maxTransferSize) || (maxTransferSize == -1));
   1.413 +		maxTransferSize = iMaxTransferSize;
   1.414 +		}
   1.415 +	else
   1.416 +		{
   1.417 +		// User doesn't care about max size
   1.418 +		if (maxTransferSize == -1)
   1.419 +			{
   1.420 +			// No maximum imposed by controller
   1.421 +			maxTransferSize = aCount;
   1.422 +			}
   1.423 +		}
   1.424 +
   1.425 +	const TInt maxAlignedSize = (maxTransferSize & ~alignMask);
   1.426 +	__DMA_ASSERTD(maxAlignedSize > 0);						// bug in PSL if not true
   1.427 +
   1.428 +	FreeDesList();
   1.429 +
   1.430 +	TInt r = KErrNone;
   1.431 +	do
   1.432 +		{
   1.433 +		// Allocate fragment
   1.434 +		r = ExpandDesList();
   1.435 +		if (r != KErrNone)
   1.436 +			{
   1.437 +			FreeDesList();
   1.438 +			break;
   1.439 +			}
   1.440 +
   1.441 +		// Compute fragment size
   1.442 +		TInt c = Min(maxTransferSize, aCount);
   1.443 +		if (memSrc && ((aFlags & KDmaPhysAddrSrc) == 0))
   1.444 +			c = MaxPhysSize(aSrc, c);
   1.445 +		if (memDest && ((aFlags & KDmaPhysAddrDest) == 0))
   1.446 +			c = MaxPhysSize(aDest, c);
   1.447 +		if ((memSrc || memDest) && (c < aCount) && (c > maxAlignedSize))
   1.448 +			{
   1.449 +			// This is not last fragment of transfer to/from memory. We must
   1.450 +			// round down fragment size so next one is correctly aligned.
   1.451 +			c = maxAlignedSize;
   1.452 +			}
   1.453 +
   1.454 +		// Initialise fragment
   1.455 +		__KTRACE_OPT(KDMA, Kern::Printf("fragment: src=0x%08X dest=0x%08X count=%d", aSrc, aDest, c));
   1.456 +		iChannel.iController->InitDes(*iLastHdr, aSrc, aDest, c, aFlags, aPslInfo, iChannel.PslId());
   1.457 +
   1.458 +		// Update for next iteration
   1.459 +		aCount -= c;
   1.460 +		if (memSrc)
   1.461 +			aSrc += c;
   1.462 +		if (memDest)
   1.463 +			aDest += c;
   1.464 +		}
   1.465 +	while (aCount > 0);
   1.466 +
   1.467 +	__DMA_INVARIANT();
   1.468 +	return r;
   1.469 +	}
   1.470 +
   1.471 +
   1.472 +
   1.473 +EXPORT_C void DDmaRequest::Queue()
   1.474 +	{
   1.475 +	__KTRACE_OPT(KDMA, Kern::Printf("DDmaRequest::Queue thread %O", &Kern::CurrentThread()));
   1.476 +	__DMA_ASSERTD(iDesCount > 0);	// Not configured? call Fragment() first !
   1.477 +	__DMA_ASSERTD(!iQueued);
   1.478 +
   1.479 +	// append request to queue and link new descriptor list to existing one.
   1.480 +	iChannel.Wait();
   1.481 +
   1.482 +	TUint32 req_count = iChannel.iQueuedRequests++;
   1.483 +	if (req_count == 0)
   1.484 +		{
   1.485 +		iChannel.Signal();
   1.486 +		iChannel.QueuedRequestCountChanged();
   1.487 +		iChannel.Wait();
   1.488 +		}
   1.489 +
   1.490 +	if (!(iChannel.iIsrDfc & (TUint32)TDmaChannel::KCancelFlagMask))
   1.491 +		{
   1.492 +		iQueued = ETrue;
   1.493 +		iChannel.iReqQ.Add(&iLink);
   1.494 +		*iChannel.iNullPtr = iFirstHdr;
   1.495 +		iChannel.iNullPtr = &(iLastHdr->iNext);
   1.496 +		iChannel.DoQueue(*this);
   1.497 +		iChannel.Signal();
   1.498 +		}
   1.499 +	else
   1.500 +		{
   1.501 +		// Someone is cancelling all requests...
   1.502 +		req_count = --iChannel.iQueuedRequests;
   1.503 +		iChannel.Signal();
   1.504 +		if (req_count == 0)
   1.505 +			{
   1.506 +			iChannel.QueuedRequestCountChanged();
   1.507 +			}
   1.508 +		}
   1.509 +
   1.510 +	__DMA_INVARIANT();
   1.511 +	}
   1.512 +
   1.513 +EXPORT_C TInt DDmaRequest::ExpandDesList(TInt aCount)
   1.514 +	{
   1.515 +	__DMA_ASSERTD(!iQueued);
   1.516 +	__DMA_ASSERTD(aCount > 0);
   1.517 +
   1.518 +	if (aCount > iChannel.iAvailDesCount)
   1.519 +		return KErrTooBig;
   1.520 +
   1.521 +	iChannel.iAvailDesCount -= aCount;
   1.522 +	iDesCount += aCount;
   1.523 +
   1.524 +	TDmac& c = *(iChannel.iController);
   1.525 +	c.Wait();
   1.526 +
   1.527 +	if (iFirstHdr == NULL)
   1.528 +		{
   1.529 +		// handle empty list specially to simplify following loop
   1.530 +		iFirstHdr = iLastHdr = c.iFreeHdr;
   1.531 +		c.iFreeHdr = c.iFreeHdr->iNext;
   1.532 +		--aCount;
   1.533 +		}
   1.534 +	else
   1.535 +		iLastHdr->iNext = c.iFreeHdr;
   1.536 +
   1.537 +	// Remove as many descriptors and headers from free pool as necessary and
   1.538 +	// ensure hardware descriptors are chained together.
   1.539 +	while (aCount-- > 0)
   1.540 +		{
   1.541 +		__DMA_ASSERTD(c.iFreeHdr != NULL);
   1.542 +		if (c.iCaps & TDmac::KCapsBitHwDes)
   1.543 +			c.ChainHwDes(*iLastHdr, *(c.iFreeHdr));
   1.544 +		iLastHdr = c.iFreeHdr;
   1.545 +		c.iFreeHdr = c.iFreeHdr->iNext;
   1.546 +		}
   1.547 +
   1.548 +	c.Signal();
   1.549 +
   1.550 +	iLastHdr->iNext = NULL;
   1.551 +
   1.552 +	__DMA_INVARIANT();
   1.553 +	return KErrNone;
   1.554 +	}
   1.555 +
   1.556 +
   1.557 +
   1.558 +
   1.559 +EXPORT_C void DDmaRequest::FreeDesList()
   1.560 +	{
   1.561 +	__DMA_ASSERTD(!iQueued);
   1.562 +	if (iDesCount > 0)
   1.563 +		{
   1.564 +		iChannel.iAvailDesCount += iDesCount;
   1.565 +		TDmac& c = *(iChannel.iController);
   1.566 +		c.Wait();
   1.567 +		iLastHdr->iNext = c.iFreeHdr;
   1.568 +		c.iFreeHdr = iFirstHdr;
   1.569 +		c.Signal();
   1.570 +		iFirstHdr = iLastHdr = NULL;
   1.571 +		iDesCount = 0;
   1.572 +		}
   1.573 +	}
   1.574 +
   1.575 +
   1.576 +#ifdef _DEBUG
   1.577 +
   1.578 +void DDmaRequest::Invariant()
   1.579 +	{
   1.580 +	iChannel.Wait();
   1.581 +	__DMA_ASSERTD(iChannel.IsOpened());
   1.582 +	__DMA_ASSERTD(0 <= iMaxTransferSize);
   1.583 +	__DMA_ASSERTD(0 <= iDesCount && iDesCount <= iChannel.iMaxDesCount);
   1.584 +	if (iDesCount == 0)
   1.585 +		{
   1.586 +		__DMA_ASSERTD(!iQueued);
   1.587 +		__DMA_ASSERTD(!iFirstHdr && !iLastHdr);
   1.588 +		}
   1.589 +	else
   1.590 +		{
   1.591 +		__DMA_ASSERTD(iChannel.iController->IsValidHdr(iFirstHdr));
   1.592 +		__DMA_ASSERTD(iChannel.iController->IsValidHdr(iLastHdr));
   1.593 +		}
   1.594 +	iChannel.Signal();
   1.595 +	}
   1.596 +
   1.597 +#endif
   1.598 +
   1.599 +
   1.600 +//////////////////////////////////////////////////////////////////////////////
   1.601 +// TDmaChannel
   1.602 +
   1.603 +
   1.604 +EXPORT_C TInt TDmaChannel::StaticExtension(TInt aCmd, TAny* aArg)
   1.605 +	{
   1.606 +	return DmaChannelMgr::StaticExtension(aCmd, aArg);
   1.607 +	}
   1.608 +
   1.609 +
   1.610 +TDmaChannel::TDmaChannel()
   1.611 +	: iController(NULL),
   1.612 +	  iPslId(0),
   1.613 +	  iCurHdr(NULL),
   1.614 +	  iNullPtr(&iCurHdr),
   1.615 +	  iDfc(Dfc, NULL, 0),
   1.616 +	  iMaxDesCount(0),
   1.617 +	  iAvailDesCount(0),
   1.618 +	  iIsrDfc(0),
   1.619 +	  iReqQ(),
   1.620 +	  iReqCount(0),
   1.621 +	  iQueuedRequests(0),
   1.622 +	  iCancelInfo(NULL)
   1.623 +	{
   1.624 +	__DMA_INVARIANT();
   1.625 +	}
   1.626 +
   1.627 +
   1.628 +EXPORT_C TInt TDmaChannel::Open(const SCreateInfo& aInfo, TDmaChannel*& aChannel)
   1.629 +	{
   1.630 +	__KTRACE_OPT(KDMA, Kern::Printf("TDmaChannel::Open thread %O", &Kern::CurrentThread()));
   1.631 +	__DMA_ASSERTD(aInfo.iDfcQ != NULL);
   1.632 +	__DMA_ASSERTD(aInfo.iDfcPriority < KNumDfcPriorities);
   1.633 +	__DMA_ASSERTD(aInfo.iDesCount >= 1);
   1.634 +
   1.635 +	aChannel = NULL;
   1.636 +
   1.637 +	DmaChannelMgr::Wait();
   1.638 +	TDmaChannel* pC = DmaChannelMgr::Open(aInfo.iCookie);
   1.639 +	DmaChannelMgr::Signal();
   1.640 +	if (!pC)
   1.641 +		return KErrInUse;
   1.642 +
   1.643 +	TInt r = pC->iController->ReserveSetOfDes(aInfo.iDesCount);
   1.644 +	if (r != KErrNone)
   1.645 +		{
   1.646 +		pC->Close();
   1.647 +		return r;
   1.648 +		}
   1.649 +	pC->iAvailDesCount = pC->iMaxDesCount = aInfo.iDesCount;
   1.650 +
   1.651 +	new (&pC->iDfc) TDfc(&Dfc, pC, aInfo.iDfcQ, aInfo.iDfcPriority);
   1.652 +
   1.653 +	aChannel = pC;
   1.654 +
   1.655 +#ifdef _DEBUG
   1.656 +	pC->Invariant();
   1.657 +#endif
   1.658 +	__KTRACE_OPT(KDMA, Kern::Printf("opened channel %d", pC->iPslId));
   1.659 +	return KErrNone;
   1.660 +	}
   1.661 +
   1.662 +
   1.663 +EXPORT_C void TDmaChannel::Close()
   1.664 +	{
   1.665 +	__KTRACE_OPT(KDMA, Kern::Printf("TDmaChannel::Close %d", iPslId));
   1.666 +	__DMA_ASSERTD(IsOpened());
   1.667 +	__DMA_ASSERTD(IsQueueEmpty());
   1.668 +	__DMA_ASSERTD(iReqCount == 0);
   1.669 +
   1.670 +	__DMA_ASSERTD(iQueuedRequests == 0);
   1.671 +
   1.672 +	// descriptor leak? bug in request code
   1.673 +	__DMA_ASSERTD(iAvailDesCount == iMaxDesCount);
   1.674 +
   1.675 +	iController->ReleaseSetOfDes(iMaxDesCount);
   1.676 +	iAvailDesCount = iMaxDesCount = 0;
   1.677 +
   1.678 +	DmaChannelMgr::Wait();
   1.679 +	DmaChannelMgr::Close(this);
   1.680 +	iController = NULL;
   1.681 +	DmaChannelMgr::Signal();
   1.682 +
   1.683 +	__DMA_INVARIANT();
   1.684 +	}
   1.685 +
   1.686 +
   1.687 +EXPORT_C void TDmaChannel::CancelAll()
   1.688 +	{
   1.689 +	__KTRACE_OPT(KDMA, Kern::Printf("TDmaChannel::CancelAll thread %O channel - %d",
   1.690 +									&Kern::CurrentThread(), iPslId));
   1.691 +	__DMA_ASSERTD(IsOpened());
   1.692 +
   1.693 +	NThread* nt = NKern::CurrentThread();
   1.694 +	TBool wait = FALSE;
   1.695 +	TDmaCancelInfo c;
   1.696 +	TDmaCancelInfo* waiters = 0;
   1.697 +
   1.698 +	NKern::ThreadEnterCS();
   1.699 +	Wait();
   1.700 +	const TUint32 req_count_before = iQueuedRequests;
   1.701 +	NThreadBase* dfcnt = iDfc.Thread();
   1.702 +	__e32_atomic_store_ord32(&iIsrDfc, (TUint32)KCancelFlagMask);
   1.703 +	// ISRs after this point will not post a DFC, however a DFC may already be queued or running or both
   1.704 +	if (!IsQueueEmpty())
   1.705 +		{
   1.706 +		// There is a transfer in progress.  It may complete before the DMAC
   1.707 +		// has stopped, but the resulting ISR will not post a DFC.
   1.708 +		// ISR should not happen after this function returns.
   1.709 +		iController->StopTransfer(*this);
   1.710 +
   1.711 +		ResetStateMachine();
   1.712 +
   1.713 +		// Clean-up the request queue.
   1.714 +		SDblQueLink* pL;
   1.715 +		while ((pL = iReqQ.GetFirst()) != NULL)
   1.716 +			{
   1.717 +			iQueuedRequests--;
   1.718 +			DDmaRequest* pR = _LOFF(pL, DDmaRequest, iLink);
   1.719 +			pR->OnDeque();
   1.720 +			}
   1.721 +		}
   1.722 +	if (!dfcnt || dfcnt==nt)
   1.723 +		{
   1.724 +		// no DFC queue or DFC runs in this thread, so just cancel it and we're finished
   1.725 +		iDfc.Cancel();
   1.726 +
   1.727 +		// if other calls to CancelAll() are waiting for the DFC, release them here
   1.728 +		waiters = iCancelInfo;
   1.729 +		iCancelInfo = 0;
   1.730 +
   1.731 +		// reset the ISR count
   1.732 +		__e32_atomic_store_rel32(&iIsrDfc, 0);
   1.733 +		}
   1.734 +	else
   1.735 +		{
   1.736 +		// DFC runs in another thread. Make sure it's queued and then wait for it to run.
   1.737 +		if (iCancelInfo)
   1.738 +			c.InsertBefore(iCancelInfo);
   1.739 +		else
   1.740 +			iCancelInfo = &c;
   1.741 +		wait = TRUE;
   1.742 +		iDfc.Enque();
   1.743 +		}
   1.744 +	const TUint32 req_count_after = iQueuedRequests;
   1.745 +	Signal();
   1.746 +	if (waiters)
   1.747 +		waiters->Signal();
   1.748 +	if (wait)
   1.749 +		NKern::FSWait(&c.iSem);
   1.750 + 	NKern::ThreadLeaveCS();
   1.751 +
   1.752 +	// Only call PSL if there were requests queued when we entered AND there
   1.753 +	// are now no requests left on the queue.
   1.754 +	if ((req_count_before != 0) && (req_count_after == 0))
   1.755 +		{
   1.756 +		QueuedRequestCountChanged();
   1.757 +		}
   1.758 +
   1.759 +	__DMA_INVARIANT();
   1.760 +	}
   1.761 +
   1.762 +
   1.763 +/**
   1.764 + DFC callback function (static member).
   1.765 + */
   1.766 +
   1.767 +void TDmaChannel::Dfc(TAny* aArg)
   1.768 +	{
   1.769 +	((TDmaChannel*)aArg)->DoDfc();
   1.770 +	}
   1.771 +
   1.772 +
   1.773 +void TDmaChannel::DoDfc()
   1.774 +	{
   1.775 +	Wait();
   1.776 +
   1.777 +	// Atomically fetch and reset the number of DFC queued by ISR and the error
   1.778 +	// flag. Leave the cancel flag alone for now.
   1.779 +	const TUint32 w = __e32_atomic_and_ord32(&iIsrDfc, (TUint32)KCancelFlagMask);
   1.780 +	TUint32 count = w & KDfcCountMask;
   1.781 +	const TBool error = w & (TUint32)KErrorFlagMask;
   1.782 +	TBool stop = w & (TUint32)KCancelFlagMask;
   1.783 +	__DMA_ASSERTD(count>0 || stop);
   1.784 +	const TUint32 req_count_before = iQueuedRequests;
   1.785 +	TUint32 req_count_after = 0;
   1.786 +
   1.787 +	while(count && !stop)
   1.788 +		{
   1.789 +		--count;
   1.790 +
   1.791 +		// If an error occurred it must have been reported on the last interrupt since transfers are
   1.792 +		// suspended after an error.
   1.793 +		DDmaRequest::TResult res = (count==0 && error) ? DDmaRequest::EError : DDmaRequest::EOk;
   1.794 +		__DMA_ASSERTD(!iReqQ.IsEmpty());
   1.795 +		DDmaRequest* pCompletedReq = NULL;
   1.796 +		DDmaRequest* pCurReq = _LOFF(iReqQ.First(), DDmaRequest, iLink);
   1.797 +		DDmaRequest::TCallback cb = 0;
   1.798 +		TAny* arg = 0;
   1.799 +
   1.800 +		if (res == DDmaRequest::EOk)
   1.801 +			{
   1.802 +			// Update state machine, current fragment, completed fragment and
   1.803 +			// tell DMAC to transfer next fragment if necessary.
   1.804 +			SDmaDesHdr* pCompletedHdr = NULL;
   1.805 +			DoDfc(*pCurReq, pCompletedHdr);
   1.806 +
   1.807 +			// If just completed last fragment from current request, switch to next
   1.808 +			// request (if any).
   1.809 +			if (pCompletedHdr == pCurReq->iLastHdr)
   1.810 +				{
   1.811 +				pCompletedReq = pCurReq;
   1.812 +				pCurReq->iLink.Deque();
   1.813 +				iQueuedRequests--;
   1.814 +				if (iReqQ.IsEmpty())
   1.815 +					iNullPtr = &iCurHdr;
   1.816 +				pCompletedReq->OnDeque();
   1.817 +				}
   1.818 +			}
   1.819 +		else if (res == DDmaRequest::EError)
   1.820 +			pCompletedReq = pCurReq;
   1.821 +		else
   1.822 +			__DMA_CANT_HAPPEN();
   1.823 +		if (pCompletedReq)
   1.824 +			{
   1.825 +			cb = pCompletedReq->iCb;
   1.826 +			arg = pCompletedReq->iCbArg;
   1.827 +			Signal();
   1.828 +			__KTRACE_OPT(KDMA, Kern::Printf("notifying DMA client result=%d", res));
   1.829 +			(*cb)(res,arg);
   1.830 +			Wait();
   1.831 +			}
   1.832 +		if (pCompletedReq || Flash())
   1.833 +			stop = __e32_atomic_load_acq32(&iIsrDfc) & (TUint32)KCancelFlagMask;
   1.834 +		}
   1.835 +
   1.836 +	// Some interrupts may be missed (double-buffer and scatter-gather
   1.837 +	// controllers only) if two or more transfers complete while interrupts are
   1.838 +	// disabled in the CPU. If this happens, the framework will go out of sync
   1.839 +	// and leave some orphaned requests in the queue.
   1.840 +	//
   1.841 +	// To ensure correctness we handle this case here by checking that the request
   1.842 +	// queue is empty when all transfers have completed and, if not, cleaning up
   1.843 +	// and notifying the client of the completion of the orphaned requests.
   1.844 +	//
   1.845 +	// Note that if some interrupts are missed and the controller raises an
   1.846 +	// error while transferring a subsequent fragment, the error will be reported
   1.847 +	// on a fragment which was successfully completed.  There is no easy solution
   1.848 +	// to this problem, but this is okay as the only possible action following a
   1.849 +	// failure is to flush the whole queue.
   1.850 +	if (stop)
   1.851 +		{
   1.852 +		TDmaCancelInfo* waiters = iCancelInfo;
   1.853 +		iCancelInfo = 0;
   1.854 +
   1.855 +		// make sure DFC doesn't run again until a new request completes
   1.856 +		iDfc.Cancel();
   1.857 +
   1.858 +		// reset the ISR count - new requests can now be processed
   1.859 +		__e32_atomic_store_rel32(&iIsrDfc, 0);
   1.860 +
   1.861 +		req_count_after = iQueuedRequests;
   1.862 +		Signal();
   1.863 +
   1.864 +		// release threads doing CancelAll()
   1.865 +		waiters->Signal();
   1.866 +		}
   1.867 +	else if (!error && !iDfc.Queued() && !iReqQ.IsEmpty() && iController->IsIdle(*this))
   1.868 +		{
   1.869 +		__KTRACE_OPT(KDMA, Kern::Printf("Missed interrupt(s) - draining request queue"));
   1.870 +		ResetStateMachine();
   1.871 +
   1.872 +		// Move orphaned requests to temporary queue so channel queue can
   1.873 +		// accept new requests.
   1.874 +		SDblQue q;
   1.875 +		q.MoveFrom(&iReqQ);
   1.876 +
   1.877 +		SDblQueLink* pL;
   1.878 +		while ((pL = q.GetFirst()) != NULL)
   1.879 +			{
   1.880 +			iQueuedRequests--;
   1.881 +			DDmaRequest* pR = _LOFF(pL, DDmaRequest, iLink);
   1.882 +			__KTRACE_OPT(KDMA, Kern::Printf("Removing request from queue and notifying client"));
   1.883 +			pR->OnDeque();
   1.884 +			DDmaRequest::TCallback cb = pR->iCb;
   1.885 +			TAny* arg = pR->iCbArg;
   1.886 +			if (cb)
   1.887 +				{
   1.888 +				Signal();
   1.889 +				(*cb)(DDmaRequest::EOk, arg);
   1.890 +				Wait();
   1.891 +				}
   1.892 +			}
   1.893 +		req_count_after = iQueuedRequests;
   1.894 +		Signal();
   1.895 +		}
   1.896 +	else
   1.897 +		{
   1.898 +		req_count_after = iQueuedRequests;
   1.899 +		Signal();
   1.900 +		}
   1.901 +
   1.902 +	// Only call PSL if there were requests queued when we entered AND there
   1.903 +	// are now no requests left on the queue (after also having executed all
   1.904 +	// client callbacks).
   1.905 +	if ((req_count_before != 0) && (req_count_after == 0))
   1.906 +		{
   1.907 +		QueuedRequestCountChanged();
   1.908 +		}
   1.909 +
   1.910 +	__DMA_INVARIANT();
   1.911 +	}
   1.912 +
   1.913 +
   1.914 +/** Reset state machine only, request queue is unchanged */
   1.915 +
   1.916 +void TDmaChannel::ResetStateMachine()
   1.917 +	{
   1.918 +	DoCancelAll();
   1.919 +	iCurHdr = NULL;
   1.920 +	iNullPtr = &iCurHdr;
   1.921 +	}
   1.922 +
   1.923 +
   1.924 +/** Unlink the last item of a LLI chain from the next chain.
   1.925 +	Default implementation does nothing. This is overridden by scatter-gather channels. */
   1.926 +
   1.927 +void TDmaChannel::DoUnlink(SDmaDesHdr& /*aHdr*/)
   1.928 +	{
   1.929 +	}
   1.930 +
   1.931 +
   1.932 +/** PSL may override */
   1.933 +void TDmaChannel::QueuedRequestCountChanged()
   1.934 +	{
   1.935 +#ifdef _DEBUG
   1.936 +	Wait();
   1.937 +	__KTRACE_OPT(KDMA,
   1.938 +				 Kern::Printf("TDmaChannel::QueuedRequestCountChanged() %d",
   1.939 +							  iQueuedRequests));
   1.940 +	__DMA_ASSERTA(iQueuedRequests >= 0);
   1.941 +	Signal();
   1.942 +#endif
   1.943 +	}
   1.944 +
   1.945 +
   1.946 +#ifdef _DEBUG
   1.947 +
   1.948 +void TDmaChannel::Invariant()
   1.949 +	{
   1.950 +	Wait();
   1.951 +
   1.952 +	__DMA_ASSERTD(iReqCount >= 0);
   1.953 +	// should always point to NULL pointer ending fragment queue
   1.954 +	__DMA_ASSERTD(*iNullPtr == NULL);
   1.955 +
   1.956 +	__DMA_ASSERTD(0 <= iAvailDesCount && iAvailDesCount <= iMaxDesCount);
   1.957 +
   1.958 +	__DMA_ASSERTD(iCurHdr == NULL || iController->IsValidHdr(iCurHdr));
   1.959 +
   1.960 +	if (IsOpened())
   1.961 +		{
   1.962 +		__DMA_ASSERTD((iCurHdr && !IsQueueEmpty()) || (!iCurHdr && IsQueueEmpty()));
   1.963 +		if (iCurHdr == NULL)
   1.964 +			__DMA_ASSERTD(iNullPtr == &iCurHdr);
   1.965 +		}
   1.966 +	else
   1.967 +		{
   1.968 +		__DMA_ASSERTD(iCurHdr == NULL);
   1.969 +		__DMA_ASSERTD(iNullPtr == &iCurHdr);
   1.970 +		__DMA_ASSERTD(IsQueueEmpty());
   1.971 +		}
   1.972 +
   1.973 +	Signal();
   1.974 +	}
   1.975 +
   1.976 +#endif
   1.977 +
   1.978 +//////////////////////////////////////////////////////////////////////////////
   1.979 +// TDmaSbChannel
   1.980 +
   1.981 +void TDmaSbChannel::DoQueue(DDmaRequest& /*aReq*/)
   1.982 +	{
   1.983 +	if (!iTransferring)
   1.984 +		{
   1.985 +		iController->Transfer(*this, *iCurHdr);
   1.986 +		iTransferring = ETrue;
   1.987 +		}
   1.988 +	}
   1.989 +
   1.990 +
   1.991 +void TDmaSbChannel::DoCancelAll()
   1.992 +	{
   1.993 +	__DMA_ASSERTD(iTransferring);
   1.994 +	iTransferring = EFalse;
   1.995 +	}
   1.996 +
   1.997 +
   1.998 +void TDmaSgChannel::DoUnlink(SDmaDesHdr& aHdr)
   1.999 +	{
  1.1000 +	iController->UnlinkHwDes(*this, aHdr);
  1.1001 +	}
  1.1002 +
  1.1003 +
  1.1004 +void TDmaSbChannel::DoDfc(DDmaRequest& /*aCurReq*/, SDmaDesHdr*& aCompletedHdr)
  1.1005 +	{
  1.1006 +	__DMA_ASSERTD(iTransferring);
  1.1007 +	aCompletedHdr = iCurHdr;
  1.1008 +	iCurHdr = iCurHdr->iNext;
  1.1009 +	if (iCurHdr != NULL)
  1.1010 +		iController->Transfer(*this, *iCurHdr);
  1.1011 +	else
  1.1012 +		iTransferring = EFalse;
  1.1013 +	}
  1.1014 +
  1.1015 +
  1.1016 +//////////////////////////////////////////////////////////////////////////////
  1.1017 +// TDmaDbChannel
  1.1018 +
  1.1019 +void TDmaDbChannel::DoQueue(DDmaRequest& aReq)
  1.1020 +	{
  1.1021 +	switch (iState)
  1.1022 +		{
  1.1023 +	case EIdle:
  1.1024 +		iController->Transfer(*this, *iCurHdr);
  1.1025 +		if (iCurHdr->iNext)
  1.1026 +			{
  1.1027 +			iController->Transfer(*this, *(iCurHdr->iNext));
  1.1028 +			iState = ETransferring;
  1.1029 +			}
  1.1030 +		else
  1.1031 +			iState = ETransferringLast;
  1.1032 +		break;
  1.1033 +	case ETransferring:
  1.1034 +		// nothing to do
  1.1035 +		break;
  1.1036 +	case ETransferringLast:
  1.1037 +		iController->Transfer(*this, *(aReq.iFirstHdr));
  1.1038 +		iState = ETransferring;
  1.1039 +		break;
  1.1040 +	default:
  1.1041 +		__DMA_CANT_HAPPEN();
  1.1042 +		}
  1.1043 +	}
  1.1044 +
  1.1045 +
  1.1046 +void TDmaDbChannel::DoCancelAll()
  1.1047 +	{
  1.1048 +	iState = EIdle;
  1.1049 +	}
  1.1050 +
  1.1051 +
  1.1052 +void TDmaDbChannel::DoDfc(DDmaRequest& /*aCurReq*/, SDmaDesHdr*& aCompletedHdr)
  1.1053 +	{
  1.1054 +	aCompletedHdr = iCurHdr;
  1.1055 +	iCurHdr = iCurHdr->iNext;
  1.1056 +	switch (iState)
  1.1057 +		{
  1.1058 +	case ETransferringLast:
  1.1059 +		iState = EIdle;
  1.1060 +		break;
  1.1061 +	case ETransferring:
  1.1062 +		if (iCurHdr->iNext == NULL)
  1.1063 +			iState = ETransferringLast;
  1.1064 +		else
  1.1065 +			iController->Transfer(*this, *(iCurHdr->iNext));
  1.1066 +		break;
  1.1067 +	default:
  1.1068 +		__DMA_CANT_HAPPEN();
  1.1069 +		}
  1.1070 +	}
  1.1071 +
  1.1072 +
  1.1073 +//////////////////////////////////////////////////////////////////////////////
  1.1074 +// TDmaSgChannel
  1.1075 +
  1.1076 +void TDmaSgChannel::DoQueue(DDmaRequest& aReq)
  1.1077 +	{
  1.1078 +	if (iTransferring)
  1.1079 +		{
  1.1080 +		__DMA_ASSERTD(!aReq.iLink.Alone());
  1.1081 +		DDmaRequest* pReqPrev = _LOFF(aReq.iLink.iPrev, DDmaRequest, iLink);
  1.1082 +		iController->AppendHwDes(*this, *(pReqPrev->iLastHdr), *(aReq.iFirstHdr));
  1.1083 +		}
  1.1084 +	else
  1.1085 +		{
  1.1086 +		iController->Transfer(*this, *(aReq.iFirstHdr));
  1.1087 +		iTransferring = ETrue;
  1.1088 +		}
  1.1089 +	}
  1.1090 +
  1.1091 +
  1.1092 +void TDmaSgChannel::DoCancelAll()
  1.1093 +	{
  1.1094 +	__DMA_ASSERTD(iTransferring);
  1.1095 +	iTransferring = EFalse;
  1.1096 +	}
  1.1097 +
  1.1098 +
  1.1099 +void TDmaSgChannel::DoDfc(DDmaRequest& aCurReq, SDmaDesHdr*& aCompletedHdr)
  1.1100 +	{
  1.1101 +	__DMA_ASSERTD(iTransferring);
  1.1102 +	aCompletedHdr = aCurReq.iLastHdr;
  1.1103 +	iCurHdr = aCompletedHdr->iNext;
  1.1104 +	iTransferring = (iCurHdr != NULL);
  1.1105 +	}