// Copyright (c) 2008-2009 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\common\arm\atomic_8_16_v6.h

// 8 and 16 bit atomic operations on V6 processors using LDREX/STREX and shifts

// Must use these user side so that it will work with data paging.

// 

//

#include "atomic_ops.h"

#if defined(__CPU_ARM_HAS_LDREX_STREX_V6K) || !defined(__CPU_ARM_HAS_LDREX_STREX)

#error 8/16 bit atomic operations using LDREX/STREX

#endif

#ifdef __BARRIERS_NEEDED__

#error Barriers not supported on V6/V5, only V6K/V7

#endif

#if __DATA_SIZE__!=8 && __DATA_SIZE__!=16

#error Unsupported data size

#endif

#if defined(__OP_LOAD__)

#error Load operation not defined

#elif defined(__OP_STORE__)

#error Store operation not defined

#elif defined(__OP_RMW1__)

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,rel,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,rlx,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,ord,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,acq,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=v

	// return value in R0

	asm("bic r12, r0, #3 ");

	asm("and r3, r0, #3 ");

	asm("stmfd sp!, {r4-r5} ");

	asm("movs r4, r3, lsl #3 ");	// r4 = bit offset of data in word

#if __DATA_SIZE__==16

	asm("eor r4, r4, #16 ");		// r4 = right rotate to take hword of interest to top (0->16, 2->0)

	asm("mov r5, r4 ");

#elif __DATA_SIZE__==8

	asm("add r4, r4, #8 ");

	asm("and r4, r4, #31 ");		// right rotate to take byte of interest to top byte (0->8, 1->16, 2->24, 3->0)

	asm("rsb r5, r4, #32 ");

	asm("and r5, r5, #31 ");		// right rotate to take top byte to byte of interest (0->8, 1->16, 2->24, 3->0)

#endif

#if defined(__OP_AND__)

	asm("mvn r1, r1 ");

	asm("mvn r1, r1, lsl #%a0" : : "i" (32-__DATA_SIZE__));	// v in upper bits of r1, 1's in lower bits

#endif

	asm("1: ");

	LDREX(0,12);

	asm("mov r0, r0, ror r4 ");		// rotate so desired data is at top

#if defined(__OP_SWP__)

	asm("orr r2, r1, r0, lsl #%a0" : : "i" (__DATA_SIZE__));

	asm("mov r2, r2, ror #%a0" : : "i" (__DATA_SIZE__));

#elif defined(__OP_ADD__)

	asm("add r2, r0, r1, lsl #%a0" : : "i" (32-__DATA_SIZE__));

#elif defined(__OP_AND__)

	asm("and r2, r0, r1 ");

#elif defined(__OP_IOR__)

	asm("orr r2, r0, r1, lsl #%a0" : : "i" (32-__DATA_SIZE__));

#elif defined(__OP_XOR__)

	asm("eor r2, r0, r1, lsl #%a0" : : "i" (32-__DATA_SIZE__));

#endif

	asm("mov r2, r2, ror r5 ");		// rotate back

	STREX(3,2,12);

	asm("cmp r3, #0 ");

	asm("bne 1b ");

	asm("mov r0, r0, lsr #%a0" : : "i" (32-__DATA_SIZE__));	// shift return value so data is at bottom

	asm("ldmfd sp!, {r4-r5} ");

	__JUMP(,lr);

	}

#elif defined(__OP_CAS__)

extern "C" EXPORT_C __NAKED__ TBool __fname__(__OPERATION__,rel,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ * /*q*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=q, R2=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ TBool __fname__(__OPERATION__,rlx,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ * /*q*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=q, R2=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ TBool __fname__(__OPERATION__,ord,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ * /*q*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=q, R2=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ TBool __fname__(__OPERATION__,acq,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ * /*q*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=q, R2=v

	// return value in R0

	asm("bic r12, r0, #3 ");

	asm("and r3, r0, #3 ");

	asm("stmfd sp!, {r4-r6} ");

	asm("movs r4, r3, lsl #3 ");	// r4 = bit offset of data in word

	__LDR_INST__( ," r6, [r1] ");	// r6 = expected value

#if __DATA_SIZE__==16

	asm("mov r5, r4 ");				// r5 = right rotate to take bottom hword to hword of interest (0->0, 2->16)

	asm("eor r4, r4, #16 ");		// r4 = right rotate to take hword of interest to top (0->16, 2->0)

#elif __DATA_SIZE__==8

	asm("rsb r5, r4, #32 ");

	asm("and r5, r5, #31 ");		// right rotate to take bottom byte to byte of interest (0->0, 1->24, 2->16, 3->8)

	asm("add r4, r4, #8 ");

	asm("and r4, r4, #31 ");		// right rotate to take byte of interest to top byte (0->8, 1->16, 2->24, 3->0)

#endif

	asm("1: ");

	LDREX(0,12);

	asm("mov r0, r0, ror r4 ");		// rotate so desired data is at top

	asm("cmp r6, r0, lsr #%a0" : : "i" (32-__DATA_SIZE__));		// check desired data against expected value *q

	asm("bne 2f ");					// if no match, give up

	asm("orr r0, r2, r0, lsl #%a0" : : "i" (__DATA_SIZE__));	// substitute value v into bottom bits of r0, replacing original

	asm("mov r0, r0, ror r5 ");		// rotate back (bottom byte/hword goes to byte/hword of interest)

	STREX(3,0,12);

	asm("cmp r3, #0 ");

	asm("bne 1b ");

	asm("2: ");

	asm("movne r0, r0, lsr #%a0" : : "i" (32-__DATA_SIZE__));	// shift return value so data is at bottom

	__STR_INST__(ne, "r0, [r1] ");	// update *q with observed value

	asm("ldmfd sp!, {r4-r6} ");

	asm("movne r0, #0 ");			// if *a not updated return FALSE

	asm("moveq r0, #1 ");			// if *a updated return TRUE

	__JUMP(,lr);

	}

#elif defined(__OP_AXO__)

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,rel,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*u*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=u, R2=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,rlx,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*u*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=u, R2=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,ord,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*u*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=u, R2=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,acq,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*u*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=u, R2=v

	// return value in R0

	asm("and r3, r0, #3 ");

	asm("bic r12, r0, #3 ");

	asm("stmfd sp!, {r4-r5} ");

	asm("mvn r1, r1, lsl #%a0" : : "i" (32-__DATA_SIZE__));	// ~u in upper bits of r1, 1's in lower bits

	asm("movs r4, r3, lsl #3 ");	// r4 = bit offset of data in word

	asm("mov r1, r1, lsr #%a0" : : "i" (32-__DATA_SIZE__));	// ~u in lower bits of r1, zero extended

	asm("1: ");

	LDREX(0,12);

	asm("bic r5, r0, r1, lsl r4 ");	// r5 = r0 & u in relevant bit positions, other bit positions unchanged

	asm("eor r5, r5, r2, lsl r4 ");

	STREX(3,5,12);

	asm("cmp r3, #0 ");

	asm("bne 1b ");

	asm("mov r0, r0, lsr r4 ");		// shift original value so byte/hword of interest is at the bottom

	asm("ldmfd sp!, {r4-r5} ");

#if __DATA_SIZE__==16

	asm("bic r0, r0, #0xff000000 ");	// mask upper 16 bits

	asm("bic r0, r0, #0x00ff0000 ");

#elif __DATA_SIZE__==8

	asm("and r0, r0, #0xff ");			// mask upper 24 bits

#endif

	__JUMP(,lr);

	}

#elif defined(__OP_RMW3__)

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,rel,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*t*/, __TYPE__ /*u*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=t, R2=u, R3=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,rlx,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*t*/, __TYPE__ /*u*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=t, R2=u, R3=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,ord,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*t*/, __TYPE__ /*u*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=t, R2=u, R3=v

	// return value in R0

	// just fall through

	}

extern "C" EXPORT_C __NAKED__ __TYPE__ __fname__(__OPERATION__,acq,__DATA_SIZE__)(volatile TAny* /*a*/, __TYPE__ /*t*/, __TYPE__ /*u*/, __TYPE__ /*v*/)

	{

	// R0=a, R1=t, R2=u, R3=v

	// return value in R0

	asm("bic r12, r0, #3 ");

	asm("stmfd sp!, {r4-r7} ");

	asm("and r4, r0, #3 ");

	asm("movs r4, r4, lsl #3 ");	// r4 = bit offset of data in word

#if __DATA_SIZE__==16

	asm("eor r4, r4, #16 ");		// r4 = right rotate to take hword of interest to top (0->16, 2->0)

	asm("mov r5, r4 ");				// r5 = right rotate to undo r4

#elif __DATA_SIZE__==8

	asm("add r4, r4, #8 ");

	asm("and r4, r4, #31 ");		// right rotate to take byte of interest to top byte (0->8, 1->16, 2->24, 3->0)

	asm("rsb r5, r4, #32 ");

	asm("and r5, r5, #31 ");		// right rotate to take top byte to byte of interest (0->8, 1->16, 2->24, 3->0)

#endif

	asm("1: ");

	LDREX(0,12);

	asm("mov r0, r0, ror r4 ");		// rotate so desired data is at top

#if	defined(__OP_TAU__)

	asm("cmp r1, r0, lsr #%a0" : : "i" (32-__DATA_SIZE__));	// t - byte/hword of interest

	asm("addls r6, r0, r2, lsl #%a0" : : "i" (32-__DATA_SIZE__));	// if t<=*a add u

	asm("addhi r6, r0, r3, lsl #%a0" : : "i" (32-__DATA_SIZE__));	// if t>*a add v

#elif	defined(__OP_TAS__)

	asm("cmp r1, r0, asr #%a0" : : "i" (32-__DATA_SIZE__));	// t - byte/hword of interest

	asm("addle r6, r0, r2, lsl #%a0" : : "i" (32-__DATA_SIZE__));	// if t<=*a add u

	asm("addgt r6, r0, r3, lsl #%a0" : : "i" (32-__DATA_SIZE__));	// if t>*a add v

#endif

	asm("mov r6, r6, ror r5 ");		// rotate back

	STREX(7,6,12);

	asm("cmp r7, #0 ");

	asm("bne 1b ");

	asm("ldmfd sp!, {r4-r7} ");

#if	defined(__OP_TAU__)

	asm("mov r0, r0, lsr #%a0" : : "i" (32-__DATA_SIZE__));	// shift return value so data is at bottom

#elif	defined(__OP_TAS__)

	asm("mov r0, r0, asr #%a0" : : "i" (32-__DATA_SIZE__));	// shift return value so data is at bottom

#endif

	__JUMP(,lr);

	}

#endif

// Second inclusion undefines temporaries

#include "atomic_ops.h"