/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/

This software is provided 'as-is', without any express or implied warranty.
In no event will the authors be held liable for any damages arising from the use of this software.
Permission is granted to anyone to use this software for any purpose, 
including commercial applications, and to alter it and redistribute it freely, 
subject to the following restrictions:

1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/

#include "SpuFakeDma.h"
#include <LinearMath/btScalar.h> //for btAssert
//Disabling memcpy sometimes helps debugging DMA

#define USE_MEMCPY 1
#ifdef USE_MEMCPY

#endif


void*	cellDmaLargeGetReadOnly(void *ls, uint64_t ea, uint32_t size, uint32_t tag, uint32_t tid, uint32_t rid)
{

#if defined (__SPU__) || defined (USE_LIBSPE2)
	cellDmaLargeGet(ls,ea,size,tag,tid,rid);
	return ls;
#else
	return (void*)(uint32_t)ea;
#endif
}

void*	cellDmaSmallGetReadOnly(void *ls, uint64_t ea, uint32_t size, uint32_t tag, uint32_t tid, uint32_t rid)
{
#if defined (__SPU__) || defined (USE_LIBSPE2)
	mfc_get(ls,ea,size,tag,0,0);
	return ls;
#else
	return (void*)(uint32_t)ea;
#endif
}




void*	cellDmaGetReadOnly(void *ls, uint64_t ea, uint32_t size, uint32_t tag, uint32_t tid, uint32_t rid)
{
#if defined (__SPU__) || defined (USE_LIBSPE2)
	cellDmaGet(ls,ea,size,tag,tid,rid);
	return ls;
#else
	return (void*)(uint32_t)ea;
#endif
}


///this unalignedDma should not be frequently used, only for small data. It handles alignment and performs check on size (<16 bytes)
int stallingUnalignedDmaSmallGet(void *ls, uint64_t ea, uint32_t size)
{
	
	btAssert(size<32);
	
	ATTRIBUTE_ALIGNED16(char	tmpBuffer[32]);


	char* localStore = (char*)ls;
	uint32_t i;
	

	///make sure last 4 bits are the same, for cellDmaSmallGet
	uint32_t last4BitsOffset = ea & 0x0f;
	char* tmpTarget = tmpBuffer + last4BitsOffset;
	
#if defined (__SPU__) || defined (USE_LIBSPE2)
	
	int remainingSize = size;

//#define FORCE_cellDmaUnalignedGet 1
#ifdef FORCE_cellDmaUnalignedGet
	cellDmaUnalignedGet(tmpTarget,ea,size,DMA_TAG(1),0,0);
#else
	char* remainingTmpTarget = tmpTarget;
	uint64_t remainingEa = ea;

	while (remainingSize)
	{
		switch (remainingSize)
		{
		case 1:
		case 2:
		case 4:
		case 8:
		case 16:
			{
				mfc_get(remainingTmpTarget,remainingEa,remainingSize,DMA_TAG(1),0,0);
				remainingSize=0;
				break;
			}
		default:
			{
				//spu_printf("unaligned DMA with non-natural size:%d\n",remainingSize);
				int actualSize = 0;

				if (remainingSize > 16)
					actualSize = 16;
				else
					if (remainingSize >8)
						actualSize=8;
					else
						if (remainingSize >4)
							actualSize=4;
						else
							if (remainingSize >2)
								actualSize=2;
				mfc_get(remainingTmpTarget,remainingEa,actualSize,DMA_TAG(1),0,0);
				remainingSize-=actualSize;
				remainingTmpTarget+=actualSize;
				remainingEa += actualSize;
			}
		}
	}
#endif//FORCE_cellDmaUnalignedGet

#else
	char* mainMem = (char*)ea;
	//copy into final destination
#ifdef USE_MEMCPY
		
		memcpy(tmpTarget,mainMem,size);
#else
		for ( i=0;i<size;i++)
		{
			tmpTarget[i] = mainMem[i];
		}
#endif //USE_MEMCPY

#endif

	cellDmaWaitTagStatusAll(DMA_MASK(1));

	//this is slowish, perhaps memcpy on SPU is smarter?
	for (i=0; btLikely( i<size );i++)
	{
		localStore[i] = tmpTarget[i];
	}

	return 0;
}

#if defined (__SPU__) || defined (USE_LIBSPE2)
#else

int	cellDmaLargeGet(void *ls, uint64_t ea, uint32_t size, uint32_t tag, uint32_t tid, uint32_t rid)
{
	char* mainMem = (char*)ea;
	char* localStore = (char*)ls;

#ifdef USE_MEMCPY
	memcpy(localStore,mainMem,size);
#else
	for (uint32_t i=0;i<size;i++)
	{
		localStore[i] = mainMem[i];
	}
#endif
	return 0;
}

int	cellDmaGet(void *ls, uint64_t ea, uint32_t size, uint32_t tag, uint32_t tid, uint32_t rid)
{
	char* mainMem = (char*)ea;
	char* localStore = (char*)ls;
#ifdef USE_MEMCPY
	memcpy(localStore,mainMem,size);
#else
	for (uint32_t i=0;i<size;i++)
	{
		localStore[i] = mainMem[i];
	}	
#endif //#ifdef USE_MEMCPY
	return 0;
}

int cellDmaLargePut(const void *ls, uint64_t ea, uint32_t size, uint32_t tag, uint32_t tid, uint32_t rid)
{
	char* mainMem = (char*)ea;
	const char* localStore = (const char*)ls;
#ifdef USE_MEMCPY
	memcpy(mainMem,localStore,size);
#else
	for (uint32_t i=0;i<size;i++)
	{
		mainMem[i] = localStore[i];
	}	
#endif //#ifdef USE_MEMCPY

	return 0;
}



void	cellDmaWaitTagStatusAll(int ignore)
{

}

#endif