// usampler.cia
// 
// Copyright (c) 2007 - 2010 Accenture. All rights reserved.
// This component and the accompanying materials are made available
// under the terms of the "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:
// Accenture - Initial contribution
//


#include <platform.h>

#include <kern_priv.h>		//temporary

#if defined(__GCC32__)
// CIA symbol macros for Gcc98r2
#define CSM__ZN5NKern14CurrentContextEv " CurrentContext__5NKern"
#elif defined(__ARMCC__)
// CIA symbol macros for RVCT
#define CSM__ZN5NKern14CurrentContextEv " __cpp(NKern::CurrentContext)"
#else
// CIA symbol macros for EABI assemblers
#define CSM__ZN5NKern14CurrentContextEv " _ZN5NKern14CurrentContextEv"
#endif

__NAKED__ TUint IntStackPtr()
	{
	asm("mrs r1, cpsr ");
	asm("bic r3, r1, #0x1f ");
//#ifdef __MISA__
//	asm("orr r3, r3, #0xd1 ");		// mode_fiq, all interrupts off
//#else
	asm("orr r3, r3, #0xd2 ");		// mode_irq, all interrupts off
//#endif
	asm("msr cpsr, r3 ");
	asm("mov r0, sp ");				// r0=sp_irq or sp_fiq
	asm("msr cpsr, r1 ");			// restore interrupts
	__JUMP(,lr);
	}

__NAKED__ TUint32 SPSR()
	{
	asm("mrs r0, spsr ");
	__JUMP(,lr);
	}


// This will return 1 if it was iDFC interrupted (0 otherwise).
// As there is no Kernel interface for that, we have to 'fake' Kernel by
// setting SVC mode before calling NKern::CurrentContext.
// Without that, CurrentContext would always return EInterrupt.
__NAKED__ TUint IDFCRunning()
	{
	asm("stmfd sp!, {r4-r5} ");	

	asm("mrs r5, cpsr");							// r5 = cpsr_irq
	asm("bic r4, r5, #0xdf ");						// clear interrupt mask & CPU mode
	asm("orr r4, r4, #0xd3 ");						// disable all interrupts and set SVC mode

	asm("msr CPSR_cf, r4");   						// switch to SVC, (dissable FIQ, IRQ)
	
	// NKern::CurrentContext does not use sp (only r0,r1,r2)
	// It is just lr in svc mode we need to preserve.
	asm("mov r4, lr");             					// r4 = lr_svc
	asm("bl " CSM__ZN5NKern14CurrentContextEv ); 	// r0 = 1 if iDFC was running, 0 if a thread was running
	asm("mov lr, r4");								// lr_svc is back to original state

	asm("msr CPSR_cf, r5");							// return to IRQ mode
	
	asm("ldmfd sp!, {r4-r5} ");
	__JUMP(,lr);
	}