aboutsummaryrefslogtreecommitdiff
path: root/arch/metag/tbx/tbitimer.S
blob: 5dbeddeee7ba210d4ce4651826e4bbe65bf2a864 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/*
 * 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 <asm/tbx.h>

	.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
 */