1 /*

     2 * This component and the accompanying materials are made available

     3 * under the terms of the License "Eclipse Public License v1.0"

     4 * which accompanies this distribution, and is available

     5 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     6 *

     7 * Initial Contributors:

     8 * Accenture Ltd

     9 *

    10 * Contributors:

    11 *

    12 * Description: This file is a part of sound driver for Syborg adaptation.

    13 *

    14 */

    15 

    16 #include "virtio.h"

    17 

    18 namespace VirtIo 

    19 {

    20 

    21 #define MIN(x,y) (((x)<=(y))?(x):(y))

    22 #define INVALID_PHYSADDR(x) ((x)==TPhysAddr(-1))

    23 

    24 TInt LinearToSGL( TAny* aVirtual, TUint aSize, TAddrLen aSGL[], TUint& aSGLCount )

    25 	{

    26 	const TUint pageSize = Kern::RoundToPageSize(1);

    27 	TUint8* virtAddr = reinterpret_cast<TUint8*>( aVirtual );

    28 	TPhysAddr physAddr = Epoc::LinearToPhysical( TLinAddr(virtAddr) );

    29 	if (INVALID_PHYSADDR(physAddr))

    30 		{ return KErrArgument; }

    31 	TUint sglLimit = aSGLCount;

    32 	aSGLCount = 0;

    33 	TUint left = aSize;

    34 	while (left)

    35 		{

    36 		TPhysAddr startPhysAddr = physAddr;

    37 		TUint8* startVirtAddr = virtAddr;

    38 		while ( (left) 

    39 			&& ( Epoc::LinearToPhysical( TLinAddr(virtAddr) ) == physAddr ) )

    40 			{

    41 			TUint size = MIN(left, pageSize);

    42 			physAddr += size;

    43 			virtAddr += size;

    44 			left -= size;

    45 			}

    46 		if (INVALID_PHYSADDR(physAddr))

    47 			{ return KErrArgument; }

    48 		if ((aSGL) && (aSGLCount<sglLimit))

    49 			{

    50 			aSGL[aSGLCount].iAddr = (TUint32) startPhysAddr;

    51 			aSGL[aSGLCount].iLen = virtAddr - startVirtAddr;

    52 			}

    53 		aSGLCount++;

    54 		}

    55 	return (aSGLCount<=sglLimit)?KErrNone:KErrNoMemory;

    56 	}

    57 	

    58 } // namespace VirtIo