/* * tbitimer.S * * Copyright (C) 2001, 2002, 2007, 2012 Imagination Technologies. * * This program is free software; you can redistribute it and/or modify it under * the terms of the GNU General Public License version 2 as published by the * Free Software Foundation. * * TBI timer support routines and data values */ .file "tbitimer.S" /* * Get data structures and defines from the main C header */ #include .data .balign 8 .global ___TBITimeB .type ___TBITimeB,object ___TBITimeB: .quad 0 /* Background 'lost' ticks */ .size ___TBITimeB,.-___TBITimeB .data .balign 8 .global ___TBITimeI .type ___TBITimeI,object ___TBITimeI: .quad 0 /* Interrupt 'lost' ticks */ .size ___TBITimeI,.-___TBITimeI .data .balign 8 .global ___TBITimes .type ___TBITimes,object ___TBITimes: .long ___TBITimeB /* Table of 'lost' tick values */ .long ___TBITimeI .size ___TBITimes,.-___TBITimes /* * Flag bits for control of ___TBITimeCore */ #define TIMER_SET_BIT 1 #define TIMER_ADD_BIT 2 /* * Initialise or stop timer support * * Register Usage: D1Ar1 holds Id, D1Ar2 is initial delay or 0 * D0FrT is used to call ___TBITimeCore * D0Re0 is used for the result which is TXSTAT_TIMER_BIT * D0Ar4, D1Ar5, D0Ar6 are all used as scratch * Other registers are those set by ___TBITimeCore * A0.3 is assumed to point at ___TBITime(I/B) */ .text .balign 4 .global ___TBITimerCtrl .type ___TBITimerCtrl,function ___TBITimerCtrl: MOV D1Ar5,#TIMER_SET_BIT /* Timer SET request */ MOVT D0FrT,#HI(___TBITimeCore) /* Get timer core reg values */ CALL D0FrT,#LO(___TBITimeCore) /* and perform register update */ NEGS D0Ar6,D0Ar2 /* Set flags from time-stamp */ ASR D1Ar5,D0Ar6,#31 /* Sign extend D0Ar6 into D1Ar5 */ SETLNZ [A0.3],D0Ar6,D1Ar5 /* ___TBITime(B/I)=-Start if enable */ MOV PC,D1RtP /* Return */ .size ___TBITimerCtrl,.-___TBITimerCtrl /* * Return ___TBITimeStamp value * * Register Usage: D1Ar1 holds Id * D0FrT is used to call ___TBITimeCore * D0Re0, D1Re0 is used for the result * D1Ar3, D0Ar4, D1Ar5 * Other registers are those set by ___TBITimeCore * D0Ar6 is assumed to be the timer value read * A0.3 is assumed to point at ___TBITime(I/B) */ .text .balign 4 .global ___TBITimeStamp .type ___TBITimeStamp,function ___TBITimeStamp: MOV D1Ar5,#0 /* Timer GET request */ MOVT D0FrT,#HI(___TBITimeCore) /* Get timer core reg values */ CALL D0FrT,#LO(___TBITimeCore) /* with no register update */ ADDS D0Re0,D0Ar4,D0Ar6 /* Add current time value */ ADD D1Re0,D1Ar3,D1Ar5 /* to 64-bit signed extend time */ ADDCS D1Re0,D1Re0,#1 /* Support borrow too */ MOV PC,D1RtP /* Return */ .size ___TBITimeStamp,.-___TBITimeStamp /* * Perform ___TBITimerAdd logic * * Register Usage: D1Ar1 holds Id, D0Ar2 holds value to be added to the timer * D0Re0 is used for the result - new TIMER value * D1Ar5, D0Ar6 are used as scratch * Other registers are those set by ___TBITimeCore * D0Ar6 is assumed to be the timer value read * D0Ar4, D1Ar3 is the current value of ___TBITime(B/I) */ .text .balign 4 .global ___TBITimerAdd .type ___TBITimerAdd,function ___TBITimerAdd: MOV D1Ar5,#TIMER_ADD_BIT /* Timer ADD request */ MOVT D0FrT,#HI(___TBITimeCore) /* Get timer core reg values */ CALL D0FrT,#LO(___TBITimeCore) /* with no register update */ ADD D0Re0,D0Ar2,D0Ar6 /* Regenerate new value = result */ NEG D0Ar2,D0Ar2 /* Negate delta */ ASR D1Re0,D0Ar2,#31 /* Sign extend negated delta */ ADDS D0Ar4,D0Ar4,D0Ar2 /* Add time added to ... */ ADD D1Ar3,D1Ar3,D1Re0 /* ... real timer ... */ ADDCS D1Ar3,D1Ar3,#1 /* ... with carry */ SETL [A0.3],D0Ar4,D1Ar3 /* Update ___TBITime(B/I) */ MOV PC,D1RtP /* Return */ .size ___TBITimerAdd,.-___TBITimerAdd #ifdef TBI_1_4 /* * Perform ___TBITimerDeadline logic * NB: Delays are positive compared to the Wait values which are -ive * * Register Usage: D1Ar1 holds Id * D0Ar2 holds Delay requested * D0Re0 is used for the result - old TIMER Delay value * D1Ar5, D0Ar6 are used as scratch * Other registers are those set by ___TBITimeCore * D0Ar6 is assumed to be the timer value read * D0Ar4, D1Ar3 is the current value of ___TBITime(B/I) * */ .text .type ___TBITimerDeadline,function .global ___TBITimerDeadline .align 2 ___TBITimerDeadline: MOV D1Ar5,#TIMER_SET_BIT /* Timer SET request */ MOVT D0FrT,#HI(___TBITimeCore) /* Get timer core reg values */ CALL D0FrT,#LO(___TBITimeCore) /* with no register update */ MOV D0Re0,D0Ar6 /* Old value read = result */ SUB D0Ar2,D0Ar6,D0Ar2 /* Delta from (old - new) */ ASR D1Re0,D0Ar2,#31 /* Sign extend delta */ ADDS D0Ar4,D0Ar4,D0Ar2 /* Add time added to ... */ ADD D1Ar3,D1Ar3,D1Re0 /* ... real timer ... */ ADDCS D1Ar3,D1Ar3,#1 /* ... with carry */ SETL [A0.3],D0Ar4,D1Ar3 /* Update ___TBITime(B/I) */ MOV PC,D1RtP /* Return */ .size ___TBITimerDeadline,.-___TBITimerDeadline #endif /* TBI_1_4 */ /* * Perform core timer access logic * * Register Usage: D1Ar1 holds Id, D0Ar2 holds input value for SET and * input value for ADD * D1Ar5 controls op as SET or ADD as bit values * On return D0Ar6, D1Ar5 holds the old 64-bit timer value * A0.3 is setup to point at ___TBITime(I/B) * A1.3 is setup to point at ___TBITimes * D0Ar4, D1Ar3 is setup to value of ___TBITime(I/B) */ .text .balign 4 .global ___TBITimeCore .type ___TBITimeCore,function ___TBITimeCore: #ifndef METAC_0_1 TSTT D1Ar1,#HI(TBID_ISTAT_BIT) /* Interrupt level timer? */ #endif MOVT A1LbP,#HI(___TBITimes) ADD A1LbP,A1LbP,#LO(___TBITimes) MOV A1.3,A1LbP /* Get ___TBITimes address */ #ifndef METAC_0_1 BNZ $LTimeCoreI /* Yes: Service TXTIMERI! */ #endif LSRS D1Ar5,D1Ar5,#1 /* Carry = SET, Zero = !ADD */ GETD A0.3,[A1.3+#0] /* A0.3 == &___TBITimeB */ MOV D0Ar6,TXTIMER /* Always GET old value */ MOVCS TXTIMER,D0Ar2 /* Conditional SET operation */ ADDNZ TXTIMER,D0Ar2,D0Ar6 /* Conditional ADD operation */ #ifndef METAC_0_1 B $LTimeCoreEnd $LTimeCoreI: LSRS D1Ar5,D1Ar5,#1 /* Carry = SET, Zero = !ADD */ GETD A0.3,[A1.3+#4] /* A0.3 == &___TBITimeI */ MOV D0Ar6,TXTIMERI /* Always GET old value */ MOVCS TXTIMERI,D0Ar2 /* Conditional SET operation */ ADDNZ TXTIMERI,D0Ar2,D0Ar6 /* Conditional ADD operation */ $LTimeCoreEnd: #endif ASR D1Ar5,D0Ar6,#31 /* Sign extend D0Ar6 into D1Ar5 */ GETL D0Ar4,D1Ar3,[A0.3] /* Read ___TBITime(B/I) */ MOV PC,D0FrT /* Return quickly */ .size ___TBITimeCore,.-___TBITimeCore /* * End of tbitimer.S */