// Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of the License "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

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

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

// e32\kernel\evfp.cpp

// 

//

#include <kernel/kern_priv.h>

#include <arm.h>

#include <vfpsupport.h>

#include <arm_vfp.h>

// Trap support for ARM's vfp engine - this is called by the ARM vfpsupport

// library when it wants to raise a floating point exception in the user thread.

// We don't currently handle floating point exceptions in VFP code, and

// never enable them for the user, so if the user has enabled them and we've

// ended up here, we panic their thread.

void _vfp_fp_trap()

	{

	__KTRACE_OPT(KPANIC, Kern::Printf("ARM VFP support library raised a floating point exception, killing user thread"));

	Kern::PanicCurrentThread(KLitKernExec, ECausedException);

	}	

// Undefined instruction handler for VFP bounces, called by the kernel

// when the undefined instruction is a coprocessor instruction for

// CP10 or CP11.

TInt HandleBounce(TArmExcInfo* aExcInfo)

	{

	// iFaultAddress in aExcInfo is actually the instruction that bounced

	if (!VFPIsComputeException(aExcInfo->iFaultAddress))

		{

		// EX bit is clear, this is a real undefined instruction

		return KErrGeneral;

		}

	// Get a computation description buffer to feed to ARM's vfp library

	TVFPComputationDescription desc;

	TBool skipInstruction = VFPCollectTrapDescription(desc,aExcInfo->iFaultAddress);

	// Invoke ARM VFP computation engine to do the work

	_VFP_Computation_Engine(desc);

	if (skipInstruction)

		{

		if (aExcInfo->iCpsr & 0x20) // if in thumb mode

			aExcInfo->iR15 += 2; // skip 2 bytes, 1 thumb instruction

		else

			aExcInfo->iR15 += 4; // skip 4 bytes, 1 ARM instruction

		}

	return KErrNone;

	}

DECLARE_STANDARD_EXTENSION()

	{

	__KTRACE_OPT(KBOOT,Kern::Printf("Enabling VFPv2 bounce support extension"));

	Arm::SetVfpBounceHandler(HandleBounce);

	Arm::SetVfpDefaultFpScr(VFP_FPSCR_IEEE_NO_EXC);

	return KErrNone;

	}

// RVCT 3.1 vfpsupport library expects the CRT abort() function to be present.

#ifdef __ARMCC_3_1__

extern "C" void abort()

	{

	Kern::PanicCurrentThread(_L("CRT_ABORT"), 0);

	}

#endif