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nuc-fw cleanup: old Nucleus demo (w/o TI fw framework) moved out of the way
author Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
date Mon, 11 Nov 2013 10:17:08 +0000
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137:5fe5559003b7 138:85994b210f6a
1 /*
2 ************************************************************************
3 *
4 * Copyright Mentor Graphics Corporation 2002
5 * All Rights Reserved.
6 *
7 * THIS WORK CONTAINS TRADE SECRET AND PROPRIETARY INFORMATION WHICH IS
8 * THE PROPERTY OF MENTOR GRAPHICS CORPORATION OR ITS LICENSORS AND IS
9 * SUBJECT TO LICENSE TERMS.
10 *
11 ************************************************************************
12 ************************************************************************
13 *
14 * FILE NAME VERSION
15 *
16 * tct.s Nucleus PLUS\ARM925\Code Composer 1.14.1
17 *
18 * COMPONENT
19 *
20 * TC - Thread Control
21 *
22 * DESCRIPTION
23 *
24 * This file contains the target processor dependent routines for
25 * performing target-dependent scheduling functions.
26 *
27 * FUNCTIONS
28 *
29 * TCT_Control_Interrupts Enable / disable interrupts
30 * by changing
31 * TCD_Interrupt_Level
32 * TCT_Local_Control_Interrupts Enable/disable interrupts
33 * by not changing
34 * TCD_Interrupt_Level
35 * TCT_Restore_Interrupts Restores interrupts to the
36 * level in TCD_Interrupt_Level
37 * TCT_Build_Task_Stack Build initial task stack
38 * TCT_Build_HISR_Stack Build initial HISR stack
39 * TCT_Build_Signal_Frame Build signal handler frame
40 * TCT_Check_Stack Check current stack
41 * TCT_Schedule Schedule the next thread
42 * TCT_Control_To_Thread Transfer control to a thread
43 * TCT_Control_To_System Transfer control from thread
44 * TCT_Signal_Exit Exit from signal handler
45 * TCT_Current_Thread Returns a pointer to current
46 * thread
47 * TCT_Set_Execute_Task Sets TCD_Execute_Task under
48 * protection from interrupts
49 * TCT_Protect Protect critical section
50 * TCT_Unprotect Unprotect critical section
51 * TCT_Unprotect_Specific Release specific protection
52 * TCT_Set_Current_Protect Set the thread's current
53 * protection field
54 * TCT_Protect_Switch Switch to protected thread
55 * TCT_Schedule_Protected Schedule the protected thread
56 * TCT_Interrupt_Context_Save Save interrupted context
57 * TCT_Interrupt_Context_Restore Restore interrupted context
58 * TCT_Activate_HISR Activate a HISR
59 * TCT_HISR_Shell HISR execution shell
60 *
61 * DEPENDENCIES
62 *
63 * cs_extr.h Common Service functions
64 * tc_extr.h Thread Control functions
65 *
66 * HISTORY
67 *
68 * NAME DATE REMARKS
69 *
70 * B. Ronquillo 08-28-2002 Released version 1.14.1
71 *
72 ************************************************************************
73 */
74
75 #define NU_SOURCE_FILE
76
77 /*
78 ******************************
79 * INCLUDE ASSEMBLY CONSTANTS *
80 ******************************
81 * Define constants used in low-level initialization.
82 */
83
84 #include "asm_defs.h"
85
86 .code 32
87
88 /* TCT_System_Limit is a global variable defined in this module */
89
90 .comm TCT_System_Limit,4,4
91
92 .text
93
94 /*
95 **********************************
96 * LOCAL VARIABLE DECLARATIONS *
97 **********************************
98 * Define pointers to system variables so their addresses may be obtained in a
99 * pc-relative manner.
100 */
101
102 System_Limit:
103 .word TCT_System_Limit
104
105 Int_Level:
106 .word TCD_Interrupt_Level
107
108 Task_Shell:
109 .word TCC_Task_Shell
110
111 HISR_Shell:
112 .word TCT_HISR_Shell
113
114 Signal_Shell:
115 .word TCC_Signal_Shell
116
117 Current_Thread:
118 .word TCD_Current_Thread
119
120 Execute_HISR:
121 .word TCD_Execute_HISR
122
123 Execute_Task:
124 .word TCD_Execute_Task
125
126 Time_Slice:
127 .word TMD_Time_Slice
128
129 Slice_State:
130 .word TMD_Time_Slice_State
131
132 System_Stack:
133 .word TCD_System_Stack
134
135 Int_Count:
136 .word TCD_Interrupt_Count
137
138 HISR_Tails:
139 .word TCD_Active_HISR_Tails
140
141 HISR_Heads:
142 .word TCD_Active_HISR_Heads
143
144 /*
145 ************************************************************************
146 *
147 * FUNCTION
148 *
149 * TCT_Control_Interrupts
150 *
151 * DESCRIPTION
152 *
153 * This function enables and disables interrupts as specified by
154 * the caller. Interrupts disabled by this call are left disabled
155 * until the another call is made to enable them.
156 *
157 * CALLED BY
158 *
159 * Application
160 *
161 * CALLS
162 *
163 * None
164 *
165 * INPUTS
166 *
167 * new_level New interrupt enable level
168 *
169 * OUTPUTS
170 *
171 * old_level Previous interrupt enable
172 * level
173 *
174 * HISTORY
175 *
176 * NAME DATE REMARKS
177 *
178 * W. Lamie 02-15-1994 Created initial version 1.0
179 * D. Lamie 02-15-1994 Verified version 1.0
180 * C. Meredith 03-01-1994 Lockout interrupts while setting
181 * up the new level, resutling in
182 * version 1.1
183 * D. Lamie 03-18-1994 Verified version 1.1
184 * M. Trippi 02-03-1997 Masked the return value to only
185 * return the interrupt bits.
186 * (SPR0252)
187 *
188 ************************************************************************
189 */
190
191 @INT TCT_Control_Interrupts (INT new_level)
192 @{
193
194 .globl TCT_Control_Interrupts
195 TCT_Control_Interrupts:
196
197 @INT old_level; Old interrupt level
198
199 @ lock out all interrupts before any checking or changing
200
201 @ Obtain the current interrupt lockout posture.
202 @ old_level = TCD_Interrupt_Level;
203
204 @ Setup new interrupt lockout posture.
205 @ TCD_Interrupt_Level = new_level;
206
207 @ renable interrupts for the specified lockout
208
209 @ Return old interrupt lockout level.
210 @ return(old_level);
211
212 MRS r2,CPSR @ Pickup current CPSR
213 ORR r2,r2,#LOCKOUT @ Build lockout CPSR
214 MSR CPSR,r2 @ Lockout interrupts temporarily
215 LDR r1, Int_Level @ Pickup interrupt level
216 LDR r3,[r1, #0] @ Pickup current interrupt lockout
217 BIC r2,r2,#LOCK_MSK @ Clear lockout mask
218 ORR r2,r2,r0 @ Build new CPSR with appropriate
219 @ interrupts locked out
220 STR r0,[r1,#0] @ Save current lockout
221 MSR CPSR,r2 @ Setup new CPSR lockout bits
222 AND r0,r3,#LOCK_MSK @ Return previous lockout (SPR0252)
223
224 BX r14 @ Return to caller
225
226 @}
227
228 /*
229 ************************************************************************
230 *
231 * FUNCTION
232 *
233 * TCT_Local_Control_Interrupts
234 *
235 * DESCRIPTION
236 *
237 * This function enables and disables interrupts as specified by
238 * the caller.
239 *
240 * CALLED BY
241 *
242 * Application
243 *
244 * CALLS
245 *
246 * None
247 *
248 * INPUTS
249 *
250 * new_level New interrupt enable level
251 *
252 * OUTPUTS
253 *
254 * old_level Previous interrupt enable
255 * level
256 *
257 * HISTORY
258 *
259 * NAME DATE REMARKS
260 *
261 * C. Meredith 03-01-1994 Created initial version 1.1
262 * D. Lamie 03-18-1994 Verified version 1.1
263 * M. Trippi 02-03-1997 Masked the return value to only
264 * return the interrupt bits.
265 * (SPR0252)
266 *
267 ************************************************************************
268 */
269
270 @INT TCT_Local_Control_Interrupts (INT new_level)
271 @{
272
273 .globl TCT_Local_Control_Interrupts
274 TCT_Local_Control_Interrupts:
275
276 @INT old_level; Old interrupt level
277
278 @ read in the old level
279 @ old_level = current interrupt level of processor;
280
281 MRS r2,CPSR @ Pickup current CPSR
282 MOV r3,r2 @ save the old level
283
284 @ clear out the old level and set the new level
285 @ current interrupt level of processor &= ~LOCKOUT;
286 @ current interrupt level of processor |= new_level;
287
288 BIC r2,r2,#LOCK_MSK @ Clear all current interrupts
289 ORR r2,r2,r0 @ Build new CPSR with new
290 @ interrupt level
291 MSR CPSR,r2 @ Setup new CPSR interrupt bits
292
293 @ Return old interrupt lockout level.
294 @ return(old_level);
295
296 AND r0,r3,#LOCK_MSK @ Return previous lockout (SPR0252)
297
298 BX r14 @ Return to caller
299
300 @}
301
302 /*
303 ************************************************************************
304 *
305 * FUNCTION
306 *
307 * TCT_Restore_Interrupts
308 *
309 * DESCRIPTION
310 *
311 * This function restores interrupts to that specified in the global
312 * TCD_Interrupt_Level variable.
313 *
314 * CALLED BY
315 *
316 * Application
317 *
318 * CALLS
319 *
320 * None
321 *
322 * INPUTS
323 *
324 * None.
325 *
326 * OUTPUTS
327 *
328 * None.
329 *
330 * HISTORY
331 *
332 * NAME DATE REMARKS
333 *
334 * C. Meredith 03-01-1994 Created initial version 1.1
335 * D. Lamie 03-18-1994 Verified version 1.1
336 *
337 ************************************************************************
338 */
339
340 @VOID TCT_Restore_Interrupts (VOID)
341 @{
342
343 .globl TCT_Restore_Interrupts
344 TCT_Restore_Interrupts:
345
346 @ Lock out all interrupts before any checking or changing
347 @ Obtain the current interrupt lockout posture.
348 @ Reload the level base on the TCD_Interrupt_Level variable
349
350 MRS r1,CPSR @ Pickup current CPSR
351 MOV r2,r1 @ save the CPSR value
352 ORR r1,r1,#LOCKOUT @ Build lockout CPSR
353 MSR CPSR,r1 @ Lockout interrupts temporarily
354 BIC r2,r2,#LOCK_MSK @ Clear current interrupt levels
355 LDR r1,Int_Level @ Load address of TCD_Interrupt_Level
356 LDR r0,[r1, #0] @ Pickup current interrupt lockout
357 ORR r2,r2,r0 @ Build new CPSR with appropriate
358 @ interrupts locked out
359 MSR CPSR,r2 @ Setup new CPSR lockout bits
360
361 BX r14 @ Return to caller
362
363 @}
364
365 /*
366 ************************************************************************
367 *
368 * FUNCTION
369 *
370 * TCT_Build_Task_Stack
371 *
372 * DESCRIPTION
373 *
374 * This function builds an initial stack frame for a task. The
375 * initial stack contains information concerning initial values of
376 * registers and the task's point of entry. Furthermore, the
377 * initial stack frame is in the same form as an interrupt stack
378 * frame.
379 *
380 * CALLED BY
381 *
382 * TCC_Create_Task Create a new task
383 * TCC_Reset_Task Reset the specified task
384 *
385 * CALLS
386 *
387 * None
388 *
389 * INPUTS
390 *
391 * task Task control block pointer
392 *
393 * OUTPUTS
394 *
395 * None
396 *
397 * HISTORY
398 *
399 * NAME DATE REMARKS
400 *
401 * W. Lamie 02-15-1994 Created initial version 1.0
402 * D. Lamie 02-15-1994 Verified version 1.0
403 *
404 ************************************************************************
405 */
406
407 @VOID TCT_Build_Task_Stack(TC_TCB *task)
408 @{
409
410 .globl TCT_Build_Task_Stack
411 TCT_Build_Task_Stack:
412
413 @ Pickup the stack base.
414 @ REG_Stack_Base = (BYTE_PTR) task -> tc_stack_start;
415
416 LDR r2,[r0,#0x24] @ Pickup the stack starting address
417
418 @ Pickup the stack size.
419 @ REG_Stack_Size = task -> tc_stack_size;
420
421 LDR r1,[r0,#0x30] @ Pickup the stack size in bytes
422
423 @ Calculate the stack ending address.
424 @ REG_Stack_End = REG_Stack_Base + REG_Stack_Size - 1;
425
426 ADD r3,r1,r2 @ Compute the beginning of stack
427 BIC r3,r3,#3 @ Insure word alignment
428 SUB r3,r3,#4 @ Reserve a word
429
430 @ Save the stack ending address.
431 @ task -> tc_stack_end = REG_Stack_End;
432
433 STR r3,[r0,#0x28] @ Save the stack ending address
434
435 @ Reference the task shell.
436 @ REG_Function_Ptr = (VOID *) TCC_Task_Shell;
437
438 @ Build an initial stack. This initial stack frame facilitates an
439 @ interrupt return to the TCC_Task_Shell function, which in turn
440 @ invokes the application task. The initial stack frame has the
441 @ following format:
442
443 @ (Lower Address) Stack Top -> 1 (Interrupt stack type)
444 @ CPSR Saved CPSR
445 @ r0 Saved r0
446 @ r1 Saved r1
447 @ r2 Saved r2
448 @ r3 Saved r3
449 @ r4 Saved r4
450 @ r5 Saved r5
451 @ r6 Saved r6
452 @ r7 Saved r7
453 @ r8 Saved r8
454 @ r9/sb Saved r9/sl
455 @ r10/sl Saved r10/sl
456 @ fp Saved fp
457 @ r12 Saved r12
458 @ r13 Saved r13
459 @ r14 Saved r14
460 @ (Higher Address) Stack Bottom-> r15 Saved r15
461
462
463 LDR r2, Task_Shell @ Pickup address of shell entry
464 STR r2,[r3], #-4 @ Store entry address on stack
465 MOV r2,#0 @ Clear value for initial registers
466 STR r2,[r3], #-4 @ Store initial r14
467 ADD r2,r3,#8 @ Compute initial r13
468 STR r2,[r3], #-4 @ Store initial r13 (Stack Bottom)
469 STR r2,[r3], #-4 @ Store initial r12
470 STR r2,[r3], #-4 @ Store initial fp
471 LDR r2,[r0,#0x24] @ Pickup the stack starting address
472 STR r2,[r3], #-4 @ Store initial r10/sl
473 MOV r2,#0 @ Clear value for initial registers
474 STR r2,[r3], #-4 @ Store initial r9/sb
475 STR r2,[r3], #-4 @ Store initial r8
476 STR r2,[r3], #-4 @ Store initial r7
477 STR r2,[r3], #-4 @ Store initial r6
478 STR r2,[r3], #-4 @ Store initial r5
479 STR r2,[r3], #-4 @ Store initial r4
480 STR r2,[r3], #-4 @ Store initial r3
481 STR r2,[r3], #-4 @ Store initial r2
482 STR r2,[r3], #-4 @ Store initial r1
483 STR r2,[r3], #-4 @ Store initial r0
484 MSR CPSR_f,r2 @ Clear the flags
485 MRS r2,CPSR @ Pickup the CPSR
486 BIC r2,r2,#LOCK_MSK @ Clear initial interrupt lockout
487 STR r2,[r3], #-4 @ Store CPSR on the initial stack
488 MOV r2,#1 @ Build interrupt stack type (1)
489 STR r2,[r3, #0] @ Store stack type on the top
490
491 @ Save the minimum amount of remaining stack memory.
492 @ task -> tc_stack_minimum = REG_Stack_Size - 72;
493
494 MOV r2,#72 @ Size of interrupt stack frame
495 SUB r1,r1,r2 @ Compute minimum available bytes
496 STR r1,[r0, #0x34] @ Save in minimum stack area
497
498 @ Save the new stack pointer into the task's control block.
499 @ task -> tc_stack_pointer = (VOID *) Stack_Top;
500
501 STR r3,[r0, #0x2C] @ Save stack pointer
502
503 BX r14 @ Return to caller
504
505 @}
506
507 /*
508 ************************************************************************
509 *
510 * FUNCTION
511 *
512 * TCT_Build_HISR_Stack
513 *
514 * DESCRIPTION
515 *
516 * This function builds an HISR stack frame that allows quick
517 * scheduling of the HISR.
518 *
519 * CALLED BY
520 *
521 * TCC_Create_HISR Create HISR function
522 *
523 * CALLS
524 *
525 * None
526 *
527 * INPUTS
528 *
529 * hisr HISR control block pointer
530 *
531 * OUTPUTS
532 *
533 * None
534 *
535 * HISTORY
536 *
537 * NAME DATE REMARKS
538 *
539 * W. Lamie 02-15-1994 Created initial version 1.0
540 * D. Lamie 02-15-1994 Verified version 1.0
541 *
542 ************************************************************************
543 */
544
545 @VOID TCT_Build_HISR_Stack(TC_HCB *hisr)
546 @{
547
548 .globl TCT_Build_HISR_Stack
549 TCT_Build_HISR_Stack:
550
551 @ Pickup the stack base.
552 @ REG_Stack_Base = (BYTE_PTR) hisr -> tc_stack_start;
553
554 LDR r2,[r0,#0x24] @ Pickup the stack starting address
555
556 @ Pickup the stack size.
557 @ REG_Stack_Size = hisr -> tc_stack_size;
558
559 LDR r1,[r0,#0x30] @ Pickup the stack size in bytes
560
561 @ Calculate the stack ending address.
562 @ REG_Stack_End = REG_Stack_Base + REG_Stack_Size;
563
564 ADD r3,r1,r2 @ Compute the beginning of stack
565 BIC r3,r3,#3 @ Insure word alignment
566 SUB r3,r3,#4 @ Reserve a word
567
568 @ Save the stack ending address.
569 @ hisr -> tc_stack_end = REG_Stack_End;
570
571 STR r3,[r0,#0x28] @ Save the stack ending address
572
573 @ Reference the HISR shell.
574 @ REG_Function_Ptr = (VOID *) TCT_HISR_Shell;
575
576 @ Build an initial stack. This initial stack frame facilitates an
577 @ solicited return to the TCT_HISR_Shell function, which in turn
578 @ invokes the appropriate HISR. The initial HISR stack frame has the
579 @ following format:
580
581 @ (Lower Address) Stack Top -> 0 (Solicited stack type)
582 @ !!FOR THUMB ONLY!! 0/0x20 Saved state mask
583 @ r4 Saved r4
584 @ r5 Saved r5
585 @ r6 Saved r6
586 @ r7 Saved r7
587 @ r8 Saved r8
588 @ r9/sb Saved r9/sl
589 @ r10/sl Saved r10/sl
590 @ fp Saved fp
591 @ r12 Saved r12
592 @ (Higher Address) Stack Bottom-> r15 Saved r15
593
594
595 LDR r2,HISR_Shell @ Pickup address of shell entry
596 STR r2,[r3], #-4 @ Store entry address on stack
597 ADD r2,r3,#4 @ Compute initial r13
598 STR r2,[r3], #-4 @ Store initial r12
599 STR r2,[r3], #-4 @ Store initial fp
600 LDR r2,[r0,#0x24] @ Pickup the stack starting address
601 STR r2,[r3], #-4 @ Store initial r10/sl
602 MOV r2,#0 @ Clear value for initial registers
603 STR r2,[r3], #-4 @ Store initial r9/sb
604 STR r2,[r3], #-4 @ Store initial r8
605 STR r2,[r3], #-4 @ Store initial r7
606 STR r2,[r3], #-4 @ Store initial r6
607 STR r2,[r3], #-4 @ Store initial r5
608 STR r2,[r3], #-4 @ Store initial r4
609 #if 1 /* was .if THUMB */
610 STR r2,[r3], #-4 @ Store initial state mask
611 #endif
612 STR r2,[r3, #0] @ Store solicited stack type on the
613 @ top of the stack
614
615 @ Save the minimum amount of remaining stack memory.
616 @ hisr -> tc_stack_minimum = REG_Stack_Size - (ARM)44 or (THUMB)48;
617
618 #if 1 /* was .if THUMB */
619 MOV r2,#48 @ Size of solicited stack frame
620 #else
621 MOV r2,#44 @ Size of solicited stack frame
622 #endif
623
624 SUB r1,r1,r2 @ Compute minimum available bytes
625 STR r1,[r0, #0x34] @ Save in minimum stack area
626
627 @ Save the new stack pointer into the task's control block.
628 @ hisr -> tc_stack_pointer = (VOID *) Stack_Top;
629
630 STR r3,[r0, #0x2C] @ Save stack pointer
631
632 BX r14 @ Return to caller
633
634 @}
635
636 /*
637 ************************************************************************
638 *
639 * FUNCTION
640 *
641 * TCT_Build_Signal_Frame
642 *
643 * DESCRIPTION
644 *
645 * This function builds a frame on top of the task's stack to
646 * cause the task's signal handler to execute the next time
647 * the task is executed.
648 *
649 * CALLED BY
650 *
651 * TCC_Send_Signals Send signals to a task
652 *
653 * CALLS
654 *
655 * None
656 *
657 * INPUTS
658 *
659 * task Task control block pointer
660 *
661 * OUTPUTS
662 *
663 * None
664 *
665 * HISTORY
666 *
667 * NAME DATE REMARKS
668 *
669 * W. Lamie 02-15-1994 Created initial version 1.0
670 * D. Lamie 02-15-1994 Verified version 1.0
671 *
672 ************************************************************************
673 */
674
675 @VOID TCT_Build_Signal_Frame(TC_TCB *task)
676 @{
677
678 .globl TCT_Build_Signal_Frame
679 TCT_Build_Signal_Frame:
680
681 @ Pickup the stack pointer.
682 @ REG_Stack_Ptr = (BYTE_PTR) task -> tc_stack_pointer;
683
684 LDR r3,[r0,#0x2c] @ Pickup the current stack pointer
685
686 @ Reference the Signal shell.
687 @ REG_Function_Ptr = (VOID *) TCC_Signal_Shell;
688
689 @ Build a signal stack. This signal stack frame facilitates an
690 @ solicited return to the TCC_Signal_Shell function, which in turn
691 @ invokes the appropriate signal handler. The initial HISR stack frame
692 @ has the following format:
693
694 @ (Lower Address) Stack Top -> 0 (Solicited stack type)
695 @ !!FOR THUMB ONLY!! 0/0x20 Saved state mask
696 @ r4 Saved r4
697 @ r5 Saved r5
698 @ r6 Saved r6
699 @ r7 Saved r7
700 @ r8 Saved r8
701 @ r9/sb Saved r9/sl
702 @ r10/sl Saved r10/sl
703 @ fp Saved fp
704 @ r12 Saved r12
705 @ (Higher Address) Stack Bottom-> r15 Saved r15
706
707
708 LDR r2,Signal_Shell @ Pickup address of shell entry
709 SUB r3,r3,#4
710 STR r2,[r3], #-4 @ Store entry address on stack
711 ADD r2,r3,#4 @ Compute initial r13
712 STR r2,[r3], #-4 @ Store initial r12
713 STR r2,[r3], #-4 @ Store initial fp
714 LDR r2,[r0,#0x24] @ Pickup the stack starting address
715 STR r2,[r3], #-4 @ Store initial r10/sl
716 MOV r2,#0 @ Clear value for initial registers
717 STR r2,[r3], #-4 @ Store initial r9/sb
718 STR r2,[r3], #-4 @ Store initial r8
719 STR r2,[r3], #-4 @ Store initial r7
720 STR r2,[r3], #-4 @ Store initial r6
721 STR r2,[r3], #-4 @ Store initial r5
722 STR r2,[r3], #-4 @ Store initial r4
723 #if 0
724 MOV r1,#0x20 @ Get initial state mask
725 STR r1,[r3], #-4 @ Store initial state mask
726 #else
727 STR r2,[r3], #-4 @ TCC_Signal_Shell is an ARM proc
728 #endif
729
730 STR r2,[r3, #0] @ Store solicited stack type on the
731 @ top of the stack
732
733 @ Save the new stack pointer into the task's control block.
734 @ task -> tc_stack_pointer = (VOID *) (REG_Stack_Ptr - REG_Stack_Size);
735
736 STR r3,[r0, #0x2C] @ Save stack pointer
737
738 BX r14 @ Return to caller
739
740 @}
741
742 /*
743 ************************************************************************
744 *
745 * FUNCTION
746 *
747 * TCT_Check_Stack
748 *
749 * DESCRIPTION
750 *
751 * This function checks the current stack for overflow conditions.
752 * Additionally, this function keeps track of the minimum amount
753 * of stack space for the calling thread and returns the current
754 * available stack space.
755 *
756 * CALLED BY
757 *
758 * TCC_Send_Signals Send signals to a task
759 *
760 * CALLS
761 *
762 * ERC_System_Error System error handler
763 *
764 * INPUTS
765 *
766 * None
767 *
768 * OUTPUTS
769 *
770 * available bytes in stack
771 *
772 * HISTORY
773 *
774 * NAME DATE REMARKS
775 *
776 * W. Lamie 02-15-1994 Created initial version 1.0
777 * D. Lamie 02-15-1994 Verified version 1.0
778 *
779 ************************************************************************
780 */
781
782 @UNSIGNED TCT_Check_Stack(void)
783 @{
784
785 .globl TCT_Check_Stack
786 TCT_Check_Stack:
787
788 @TC_TCB *thread;
789 @UNSIGNED remaining;
790
791 @ Pickup the current task/HISR pointer.
792 @ thread = (TC_TCB *) TCD_Current_Thread;
793
794 LDR r0,Current_Thread @ Pickup address of thread pointer
795 LDR r0,[r0,#0] @ Pickup thread pointer
796
797 @ Determine if there is a current thread.
798 @ if (thread)
799 @ {
800
801 CMP r0,#0 @ Determine if a thread is active
802 MOV r3,#0 @ Default remaining value
803 BEQ TCT_Skip_Stack_Check @ If NU_NULL, skip stack checking
804
805 @ Determine if the stack pointers are out of range.
806 @ if ((thread -> tc_stack_pointer < thread -> tc_stack_start) ||
807 @ (thread -> tc_stack_pointer > thread -> tc_stack_end))
808
809 LDR r2,[r0,#0x24] @ Pickup start of stack area
810 CMP r13,r2 @ Compare with current stack ptr
811 BLT TCT_Stack_Range_Error @ If less, stack is out of range
812 LDR r1,[r0,#0x28] @ Pickup end of stack area
813 CMP r13,r1 @ Compare with current stack ptr
814 BLE TCT_Stack_Range_Okay @ If less, stack range is okay
815
816 @ Stack overflow condition exits.
817 @ ERC_System_Error(NU_STACK_OVERFLOW);
818
819 TCT_Stack_Range_Error:
820
821 STR r14,[r13, #4]! @ Store r14 on the stack
822 MOV r0,#3 @ Build NU_STACK_OVERFLOW code
823 BL ERC_System_Error @ Call system error handler. Note:
824 @ control is not returned!
825 @ Examine stack to find return
826 @ address of this routine.
827
828 TCT_Stack_Range_Okay:
829
830 @ Calculate the amount of available space on the stack.
831 @ remaining = (BYTE_PTR) thread -> tc_stack_pointer -
832 @ (BYTE_PTR) thread -> tc_stack_start;
833
834 SUB r3,r13,r2 @ Calculate remaining stack size
835
836 @ Determine if there is enough memory on the stack to save all of the
837 @ registers.
838 @ if (remaining < 80)
839
840 CMP r3,#80 @ Is there enough room for an
841 @ interrupt frame?
842 BCS TCT_No_Stack_Error @ If so, no stack overflow yet
843
844 @ Stack overflow condition is about to happen.
845 @ ERC_System_Error(NU_STACK_OVERFLOW);
846
847 STR r14,[r13, #4]! @ Store r14 on the stack
848 MOV r0,#3 @ Build NU_STACK_OVERFLOW code
849 BL ERC_System_Error @ Call system error handler. Note:
850 @ control is not returned!
851 @ Examine stack to find return
852 @ address of this routine.
853
854 TCT_No_Stack_Error:
855
856 @ Determine if this is a new minimum amount of stack space.
857 @ if (remaining < thread -> tc_stack_minimum)
858
859 LDR r2,[r0,#0x34]
860 CMP r3,r2
861 STRCC r3,[r0,#0x34]
862
863 @ Save the new stack minimum.
864 @ thread -> tc_stack_minimum = remaining;
865 @ }
866 @ else
867
868 @ Set the remaining bytes to 0.
869 @ remaining = 0;
870
871 @ Return the remaining number of bytes on the stack.
872 @ return(remaining);
873
874 TCT_Skip_Stack_Check:
875 MOV r0,r3 @ Return remaining bytes
876
877 BX r14 @ Return to caller
878
879 @}
880
881 /*
882 ************************************************************************
883 *
884 * FUNCTION
885 *
886 * TCT_Schedule
887 *
888 * DESCRIPTION
889 *
890 * This function waits for a thread to become ready. Once a thread
891 * is ready, this function initiates a transfer of control to that
892 * thread.
893 *
894 * CALLED BY
895 *
896 * INC_Initialize Main initialization routine
897 *
898 * CALLS
899 *
900 * TCT_Control_To_Thread Transfer control to a thread
901 *
902 * INPUTS
903 *
904 * TCD_Execute_Task Pointer to task to execute
905 *
906 * OUTPUTS
907 *
908 * None
909 *
910 * HISTORY
911 *
912 * NAME DATE REMARKS
913 *
914 * W. Lamie 02-15-1994 Created initial version 1.0
915 * D. Lamie 02-15-1994 Verified version 1.0
916 *
917 ************************************************************************
918 */
919
920 @VOID TCT_Schedule(void)
921 @{
922
923 .globl TCT_Schedule
924 TCT_Schedule:
925
926 @ Restore interrupts according to the value contained in
927 @ TCD_Interrupt_Level.
928
929 LDR r1,Int_Level @ Build address of interrupt level
930 MRS r0,CPSR @ Pickup current CPSR
931 LDR r2,[r1, #0] @ Pickup current interrupt lockout
932 BIC r0,r0,#LOCK_MSK @ Clear the interrupt lockout bits
933 ORR r0,r0,r2 @ Build new interrupt lockout CPSR
934 MSR CPSR,r0 @ Setup new CPSR
935 LDR r2,Execute_HISR @ Pickup TCD_Execute_HISR address
936 LDR r3,Execute_Task @ Pickup TCD_Execute_Task address
937
938 #ifdef INCLUDE_PROVIEW
939 @ Nucleus ProView Hook
940 @ We check if upon entering TCT_Schedule we already have a task to excute.
941 @ if not, we start IDLE.
942 LDR r0,[r2, #0] @ Pickup highest priority HISR ptr
943 CMP r0,#0 @ Is there a HISR active?
944 BNE TCT_Schedule_Thread @ Found an HISR
945 LDR r0,[r3, #0] @ Pickup highest priority Task ptr
946 CMP r0,#0 @ Is there a task active?
947 BNE TCT_Schedule_Thread @ If not, start IDLE.
948 STR r2,[r13, #-4]! @ Save r2 on the stack
949 STR r3,[r13, #-4]! @ Save r3 on the stack
950 BL _NU_Idle_Hook
951 LDR r3,[r13], #4 @ Recover r2
952 LDR r2,[r13], #4 @ Recover r3
953 #endif
954
955
956 @ Wait until a thread (task or HISR) is available to execute.
957 @ do
958 @ {
959 TCT_Schedule_Loop:
960
961 @ } while ((!TCD_Execute_HISR) && (!TCD_Execute_Task));
962
963 LDR r0,[r2, #0] @ Pickup highest priority HISR ptr
964 CMP r0,#0 @ Is there a HISR active?
965 BNE TCT_Schedule_Thread @ Found an HISR
966 LDR r0,[r3, #0] @ Pickup highest priority Task ptr
967 CMP r0,#0 @ Is there a task active?
968 BNE TCT_Schedule_Thread
969 @ stmfd r13!,{r2-r3}
970 @ BL freecalypso_nucidle_dbghook
971 @ ldmfd r13!,{r2-r3}
972 B TCT_Schedule_Loop
973
974 @ Yes, either a task or an HISR is ready to execute. Lockout
975 @ interrupts while the thread is transferred to.
976
977 TCT_Schedule_Thread:
978 MRS r1,CPSR @ Pickup CPSR again
979 ORR r1,r1,#LOCKOUT @ Build interrupt lockout value
980 MSR CPSR,r1 @ Lockout interrupts
981
982 @ Transfer control to the thread by falling through to the following
983 @ routine.
984 @}
985
986 /*
987 ************************************************************************
988 *
989 * FUNCTION
990 *
991 * TCT_Control_To_Thread
992 *
993 * DESCRIPTION
994 *
995 * This function transfers control to the specified thread. Each
996 * time control is transferred to a thread, its scheduled counter
997 * is incremented. Additionally, time-slicing for task threads is
998 * enabled in this routine. The TCD_Current_Thread pointer is
999 * setup by this function.
1000 *
1001 * CALLED BY
1002 *
1003 * TCT_Schedule Indirectly called
1004 * TCT_Protect Protection task switch
1005 *
1006 * CALLS
1007 *
1008 * None
1009 *
1010 * INPUTS
1011 *
1012 * thread Thread control block pointer
1013 *
1014 * OUTPUTS
1015 *
1016 * None
1017 *
1018 * HISTORY
1019 *
1020 * NAME DATE REMARKS
1021 *
1022 * W. Lamie 02-15-1994 Created initial version 1.0
1023 * D. Lamie 02-15-1994 Verified version 1.0
1024 *
1025 ************************************************************************
1026 */
1027
1028 @VOID TCT_Control_To_Thread(TC_TCB *thread)
1029 @{
1030 TCT_Control_To_Thread:
1031
1032 @ Setup the current thread pointer.
1033 @ TCD_Current_Thread = (VOID *) thread;
1034
1035 LDR r1,Current_Thread @ Pickup current thread ptr address
1036 LDR r2,[r0, #0x1c] @ Pickup scheduled count
1037 STR r0,[r1, #0] @ Setup current thread pointer
1038
1039 @ Increment the thread scheduled counter.
1040 @ thread -> tc_scheduled++;
1041
1042 LDR r3,[r0, #0x20] @ Pickup time slice value
1043 ADD r2,r2,#1 @ Increment the scheduled count
1044 STR r2,[r0, #0x1c] @ Store new scheduled count
1045
1046 @ Check for time slice option.
1047 @ if (thread -> tc_cur_time_slice)
1048 @ {
1049 CMP r3,#0 @ Is there a time slice?
1050 BEQ TCT_No_Start_TS_1 @ If 0, there is no time slice
1051
1052 @ Start a time slice.
1053 @ TMD_Time_Slice = thread -> tc_cur_time_slice;
1054 @ TMD_Time_Slice_State = 0;
1055
1056 LDR r2,Time_Slice @ Pickup address of TMD_Time_Slice
1057 LDR r1,Slice_State @ Pickup address of
1058 @ TMD_Time_Slice_State
1059 STR r3,[r2, #0] @ Setup the time slice
1060 MOV r2,#0 @ Build active state flag
1061 STR r2,[r1,#0] @ Set the active flag
1062 @ }
1063 TCT_No_Start_TS_1:
1064 #ifdef INCLUDE_PROVIEW
1065 @ Nucleus ProView Hook
1066
1067 STR r0,[r13, #-4]! @ Save r0 on the stack
1068 BL _NU_Schedule_Task_Hook @ Branch to RTView
1069 LDR r0,[r13], #4 @ Recover return address
1070 #endif
1071
1072
1073 @ Pickup the stack pointer and resume the thread.
1074 @ REG_Stack_Ptr = thread -> tc_stack_pointer;
1075
1076 LDR r13,[r0, #0x2c] @ Switch to thread's stack pointer
1077
1078 @ Pop off the saved information associated with the thread. After we
1079 @ determine which type of stack is present. A 1 on the top of the
1080 @ stack indicates an interrupt stack, while a 0 on the top of the
1081 @ stack indicates a solicited type of stack.
1082
1083 @ Remember that the interrupt level that is restored must represent
1084 @ the interrupt level in TCD_Interrupt_Level.
1085
1086 LDR r1,[r13], #4 @ Pop off the stack type
1087 CMP r1,#1 @ See if it is an interrupt stack
1088 BEQ TCT_Interrupt_Resume @ If so, an interrupt resume of
1089 @ thread is required
1090 LDR r1, Int_Level @ Pickup address of interrupt
1091 @ lockout
1092 MRS r0,CPSR @ Pickup current CPSR
1093 BIC r0,r0,#LOCK_MSK @ Clear lockout mask
1094
1095 BIC r0,r0,#0x80000000
1096
1097
1098 LDR r2,[r1, #0] @ Pickup interrupt lockout mask
1099 ORR r0,r0,r2 @ Build new interrupt lockout mask
1100 #if 1 /* was .if THUMB */
1101 LDR r2,[r13], #4 @ Pop off the state mask
1102 ORR r0,r0,r2 @ Set appropriate state
1103 #endif
1104 MSR SPSR,r0 @ Place it into the SPSR
1105 LDMIA r13!,{r4-r12,r15}^ @ A solicited return is required.
1106 @ This type of return only
1107 @ recovers r4-r13 & r15
1108 TCT_Interrupt_Resume:
1109 LDR r0,[r13], #4 @ Pop off the CPSR
1110 LDR r1,Int_Level @ Pickup address of interrupt
1111 @ lockout
1112 BIC r0,r0,#LOCK_MSK @ Clear lockout mask
1113 LDR r2,[r1, #0] @ Pickup interrupt lockout mask
1114 ORR r0,r0,r2 @ Build new interrupt lockout mask
1115 MSR SPSR,r0 @ Place it into the SPSR
1116 LDMIA r13,{r0-r15}^ @ Recover all registers and resume
1117 @ at point of interrupt
1118 @}
1119
1120 /*
1121 ************************************************************************
1122 *
1123 * FUNCTION
1124 *
1125 * TCT_Control_To_System
1126 *
1127 * DESCRIPTION
1128 *
1129 * This function returns control from a thread to the system. Note
1130 * that this service is called in a solicited manner, i.e. it is
1131 * not called from an interrupt thread. Registers required by the
1132 * compiler to be preserved across function boundaries are saved by
1133 * this routine. Note that this is usually a sub-set of the total
1134 * number of available registers.
1135 *
1136 * CALLED BY
1137 *
1138 * Other Components
1139 *
1140 * CALLS
1141 *
1142 * TCT_Schedule Schedule the next thread
1143 *
1144 * INPUTS
1145 *
1146 * None
1147 *
1148 * OUTPUTS
1149 *
1150 * None
1151 *
1152 * HISTORY
1153 *
1154 * NAME DATE REMARKS
1155 *
1156 * W. Lamie 02-15-1994 Created initial version 1.0
1157 * D. Lamie 02-15-1994 Verified version 1.0
1158 * C. Meredith 03-01-1994 Corrected problem in time-slice
1159 * reset logic, resulting in
1160 * version 1.1
1161 * D. Lamie 03-18-1994 Verified version 1.1
1162 *
1163 ************************************************************************
1164 */
1165
1166 @VOID TCT_Control_To_System(void)
1167 @{
1168
1169 .globl TCT_Control_To_System
1170 TCT_Control_To_System:
1171
1172 @ Lockout interrupts.
1173
1174 MRS r0,CPSR @ Pickup current CPSR
1175 ORR r0,r0,#LOCKOUT @ Build interrupt lockout value
1176 MSR CPSR,r0 @ Lockout interrupts
1177
1178 @ Save a minimal context of the thread.
1179
1180 STMDB r13!,{r4-r12,r14} @ Save minimal context of thread on
1181 @ the current stack
1182 #if 1 /* was .if THUMB */
1183 MOV r2,r14 @ Determine what state the caller
1184 MOV r2,r2,LSL #31 @ was in and build an
1185 MOV r2,r2,LSR #26 @ appropriate state mask
1186 STR r2,[r13, #-4]! @ Place it on the stack
1187 #endif
1188
1189 MOV r2,#0 @ Build solicited stack type value
1190 @ and NU_NULL value
1191 STR r2,[r13, #-4]! @ Place it on the top of the stack
1192
1193 @ Setup a pointer to the thread control block.
1194 @ REG_Thread_Ptr = (TC_TCB *) TCD_Current_Thread;
1195
1196 LDR r1,Current_Thread @ Pickup current thread ptr address
1197 LDR r0,[r1, #0] @ Pickup current thread pointer
1198
1199 @ Clear the current thread control block pointer.
1200 @ TCD_Current_Thread = NU_NULL;
1201
1202 LDR r3,Slice_State @ Pickup time slice state address
1203 STR r2,[r1, #0] @ Set current thread pointer to
1204 @ NU_NULL
1205
1206 @ Check to see if a time slice is active. If so, copy the original time
1207 @ slice into the current time slice field of the task's control block.
1208 @ if (TMD_Time_Slice_State == 0)
1209 @ {
1210 LDR r1,[r3, #0] @ Pickup time slice state flag
1211 CMP r1,#0 @ Compare with active value
1212 BNE TCT_No_Stop_TS_1 @ If non-active, don't disable
1213
1214
1215 @ Insure that the next time the task runs it gets a fresh time
1216 @ slice.
1217 @ REG_Thread_Ptr -> tc_cur_time_slice = REG_Thread_Ptr -> tc_time_slice;
1218
1219 LDR r1,[r0, #0x40] @ Pickup original time slice
1220
1221 @ Clear any active time slice by setting the state to NOT_ACTIVE.
1222 @ TMD_Time_Slice_State = 1;
1223
1224 MOV r2,#1 @ Build disable value
1225 STR r2,[r3, #0] @ Disable time slice
1226 STR r1,[r0, #0x20] @ Reset current time slice
1227 @ }
1228 TCT_No_Stop_TS_1:
1229
1230 @ Save off the current stack pointer in the control block.
1231 @ REG_Thread_Ptr -> tc_stack_pointer = (VOID *) REG_Stack_Ptr;
1232
1233 STR r13,[r0, #0x2c] @ Save the thread's stack pointer
1234
1235 @ Clear the task's current protection.
1236 @ (REG_Thread_Ptr -> tc_current_protect) -> tc_tcb_pointer = NU_NULL;
1237 @ REG_Thread_Ptr -> tc_current_protect = NU_NULL;
1238
1239 LDR r1,[r0, #0x38] @ Pickup current thread pointer
1240 MOV r2,#0 @ Build NU_NULL value
1241 STR r2,[r0, #0x38] @ Clear the protect pointer field
1242 STR r2,[r1, #0] @ Release the actual protection
1243
1244 @ Switch to the system stack.
1245 @ REG_Stack_Ptr = TCD_System_Stack;
1246
1247 LDR r1, System_Stack @ Pickup address of stack pointer
1248 LDR r2, System_Limit @ Pickup address of stack limit ptr
1249 LDR r13,[r1, #0] @ Switch to system stack
1250 LDR r10,[r2, #0] @ Setup system stack limit
1251
1252 @ Finished, return to the scheduling loop.
1253
1254 B TCT_Schedule @ Return to scheduling loop
1255 @}
1256
1257 /*
1258 ************************************************************************
1259 *
1260 * FUNCTION
1261 *
1262 * TCT_Signal_Exit
1263 *
1264 * DESCRIPTION
1265 *
1266 * This function exits from a signal handler. The primary purpose
1267 * of this function is to clear the scheduler protection and switch
1268 * the stack pointer back to the normal task's stack pointer.
1269 *
1270 * CALLED BY
1271 *
1272 * TCC_Signal_Shell Signal handling shell func
1273 *
1274 * CALLS
1275 *
1276 * TCT_Schedule Scheduler
1277 *
1278 * INPUTS
1279 *
1280 * None
1281 *
1282 * OUTPUTS
1283 *
1284 * None
1285 *
1286 * HISTORY
1287 *
1288 * NAME DATE REMARKS
1289 *
1290 * W. Lamie 02-15-1994 Created initial version 1.0
1291 * D. Lamie 02-15-1994 Verified version 1.0
1292 * C. Meredith 03-01-1994 Corrected problem in time-slice
1293 * reset logic, resulting in
1294 * version 1.1
1295 * D. Lamie 03-18-1994 Verified version 1.1
1296 *
1297 ************************************************************************
1298 */
1299
1300 @VOID TCT_Signal_Exit(void)
1301 @{
1302
1303 .globl TCT_Signal_Exit
1304 TCT_Signal_Exit:
1305
1306 @ Lockout interrupts.
1307
1308 MRS r3,CPSR @ Pickup current CPSR
1309 ORR r3,r3,#LOCKOUT @ Build lockout value
1310 MSR CPSR,r3 @ Lockout interrupts
1311
1312 @ Setup a pointer to the thread control block.
1313 @ REG_Thread_Ptr = (TC_TCB *) TCD_Current_Thread;
1314
1315 LDR r1,Current_Thread @ Pickup address of thread pointer
1316 MOV r2,#0 @ Build NU_NULL value
1317 LDR r0,[r1,#0] @ Pickup current thread pointer
1318
1319 @ Clear the current thread control block.
1320 @ TCD_Current_Thread = NU_NULL;
1321
1322 LDR r3,Slice_State @ Pickup time slice state address
1323 STR r2,[r1, #0] @ Clear current thread pointer
1324
1325 @ Check to see if a time slice is active. If so, copy the original time
1326 @ slice into the current time slice field of the task's control block.
1327 @ if (TMD_Time_Slice_State == 0)
1328 @ {
1329
1330 LDR r1,[r3, #0] @ Pickup time slice state flag
1331 CMP r1,#0 @ Compare with active value
1332 BNE TCT_No_Stop_TS_2 @ If non-active, don't disable
1333
1334 @ Insure that the next time the task runs it gets a fresh time
1335 @ slice.
1336 @ REG_Thread_Ptr -> tc_cur_time_slice = REG_Thread_Ptr -> tc_time_slice;
1337
1338 LDR r1,[r0, #0x40] @ Pickup original time slice
1339
1340 @ Clear any active time slice by setting the state to NOT_ACTIVE.
1341 @ TMD_Time_Slice_State = 1;
1342
1343 MOV r2,#1 @ Build disable value
1344 STR r2,[r3, #0] @ Disable time slice
1345 STR r1,[r0, #0x20] @ Reset current time slice
1346 @ }
1347 TCT_No_Stop_TS_2:
1348
1349 @ Switch back to the saved stack. The saved stack pointer was saved
1350 @ before the signal frame was built.
1351 @ REG_Thread_Ptr -> tc_stack_pointer =
1352 @ REG_Thread_Ptr -> tc_saved_stack_ptr;
1353
1354 LDR r1,[r0, #0x3c] @ Pickup saved stack pointer
1355 STR r1,[r0, #0x2c] @ Place in current stack pointer
1356
1357 @ Clear the task's current protection.
1358 @ (REG_Thread_Ptr -> tc_current_protect) -> tc_tcb_pointer = NU_NULL;
1359 @ REG_Thread_Ptr -> tc_current_protect = NU_NULL;
1360
1361 LDR r1,[r0, #0x38] @ Pickup current thread pointer
1362 MOV r2,#0 @ Build NU_NULL value
1363 STR r2,[r0, #0x38] @ Clear the protect pointer field
1364 STR r2,[r1, #0] @ Release the actual protection
1365
1366 @ Switch to the system stack.
1367 @ REG_Stack_Ptr = (BYTE_PTR) TCD_System_Stack;
1368
1369 LDR r1, System_Stack @ Pickup address of stack pointer
1370 LDR r2, System_Limit @ Pickup address of stack limit ptr
1371 LDR r13,[r1, #0] @ Switch to system stack
1372 LDR r10,[r2, #0] @ Setup system stack limit
1373
1374 @ Finished, return to the scheduling loop.
1375
1376 B TCT_Schedule @ Return to scheduling loop
1377 @}
1378
1379 /*
1380 ************************************************************************
1381 *
1382 * FUNCTION
1383 *
1384 * TCT_Current_Thread
1385 *
1386 * DESCRIPTION
1387 *
1388 * This function returns the current thread pointer.
1389 *
1390 * CALLED BY
1391 *
1392 * Application
1393 * System Components
1394 *
1395 * CALLS
1396 *
1397 * None
1398 *
1399 * INPUTS
1400 *
1401 * None
1402 *
1403 * OUTPUTS
1404 *
1405 * Pointer to current thread
1406 *
1407 * HISTORY
1408 *
1409 * NAME DATE REMARKS
1410 *
1411 * W. Lamie 02-15-1994 Created initial version 1.0
1412 * D. Lamie 02-15-1994 Verified version 1.0
1413 *
1414 ************************************************************************
1415 */
1416
1417 @VOID *TCT_Current_Thread(void)
1418 @{
1419
1420 .globl TCT_Current_Thread
1421 TCT_Current_Thread:
1422
1423 @ Return the current thread pointer.
1424 @ return(TCD_Current_Thread);
1425
1426 LDR r0, Current_Thread @ Pickup address of thread pointer
1427 LDR r0,[r0, #0] @ Pickup current thread pointer
1428
1429 BX r14 @ Return to caller
1430
1431 @}
1432
1433 /*
1434 ************************************************************************
1435 *
1436 * FUNCTION
1437 *
1438 * TCT_Set_Execute_Task
1439 *
1440 * DESCRIPTION
1441 *
1442 * This function sets the current task to execute variable under
1443 * protection against interrupts.
1444 *
1445 * CALLED BY
1446 *
1447 * TCC Scheduling Routines
1448 *
1449 * CALLS
1450 *
1451 * None
1452 *
1453 * INPUTS
1454 *
1455 * task Pointer to task control block
1456 *
1457 * OUTPUTS
1458 *
1459 * TCD_Execute_Task Modified variable
1460 *
1461 * HISTORY
1462 *
1463 * NAME DATE REMARKS
1464 *
1465 * W. Lamie 02-15-1994 Created initial version 1.0
1466 * D. Lamie 02-15-1994 Verified version 1.0
1467 *
1468 ************************************************************************
1469 */
1470
1471 @VOID TCT_Set_Execute_Task(TC_TCB *task)
1472 @{
1473
1474 .globl TCT_Set_Execute_Task
1475 TCT_Set_Execute_Task:
1476
1477 @ Now setup the TCD_Execute_Task pointer.
1478 @ TCD_Execute_Task = task;
1479
1480 LDR r1, Execute_Task @ Pickup execute task ptr address
1481 STR r0,[r1,#0] @ Setup new task to execute
1482
1483 BX r14 @ Return to caller
1484
1485 @}
1486
1487 /*
1488 ************************************************************************
1489 *
1490 * FUNCTION
1491 *
1492 * TCT_Protect
1493 *
1494 * DESCRIPTION
1495 *
1496 * This function protects against multiple thread access.
1497 *
1498 * CALLED BY
1499 *
1500 * Application
1501 * System Components
1502 *
1503 * CALLS
1504 *
1505 * None
1506 *
1507 * INPUTS
1508 *
1509 * protect Pointer to protection block
1510 *
1511 * OUTPUTS
1512 *
1513 * None
1514 *
1515 * HISTORY
1516 *
1517 * NAME DATE REMARKS
1518 *
1519 * W. Lamie 02-15-1994 Created initial version 1.0
1520 * D. Lamie 02-15-1994 Verified version 1.0
1521 *
1522 ************************************************************************
1523 */
1524
1525 @VOID TCT_Protect(TC_PROTECT *protect)
1526 @{
1527
1528 .globl TCT_Protect
1529 TCT_Protect:
1530
1531 @ Determine if the caller is in a task or HISR thread.
1532 @ if (TCD_Current_Thread)
1533 @ {
1534
1535 LDR r1,Current_Thread @ Pickup current thread ptr address
1536 LDR r3,[r1, #0] @ Pickup current thread pointer
1537 CMP r3,#0 @ Check to see if it is non-NULL
1538 BEQ TCT_Skip_Protect @ If NULL, skip protection
1539
1540 @ Lockout interrupts.
1541
1542 MRS r1,CPSR @ Pickup current CPSR
1543 ORR r1,r1,#LOCKOUT @ Place lockout value in
1544 MSR CPSR,r1 @ Lockout interrupts
1545
1546 @ Wait until the protect structure is available.
1547 @ while (protect -> tc_tcb_pointer != NU_NULL)
1548 @ {
1549
1550 TCT_Protect_Loop:
1551 LDR r1,[r0, #0] @ Pickup protection owner field
1552 CMP r1,#0 @ Is there any protection?
1553 BEQ TCT_Protect_Available @ If NU_NULL, no current protection
1554
1555 @ Protection structure is not available.
1556
1557 @ Indicate that another thread is waiting.
1558 @ protect -> tc_thread_waiting = 1;
1559
1560 MOV r2,#1 @ Build thread waiting flag
1561 STR r2,[r0, #4] @ Set waiting field
1562
1563 @ Directly schedule the thread waiting.
1564 @ TCT_Schedule_Protected(protect -> tc_tcb_pointer);
1565
1566 STR r0,[r13, #-4]! @ Save r0 on the stack
1567 STR r14,[r13, #-4]! @ Save r14 on the stack
1568 MOV r0,r3 @ Place current thread into r0
1569 BL TCT_Schedule_Protected @ Call routine to schedule the
1570 @ owner of the thread
1571
1572 LDR r14,[r13], #4 @ Recover saved r14
1573 LDR r0,[r13], #4 @ Recover saved r0
1574
1575 @ Lockout interrupts.
1576
1577 LDR r1,Current_Thread @ Pickup current thread ptr address
1578 LDR r3,[r1, #0] @ Pickup current thread pointer
1579 MRS r1,CPSR @ Pickup current CPSR
1580 ORR r1,r1,#LOCKOUT @ Place lockout value in
1581 MSR CPSR,r1 @ Lockout interrupts
1582 B TCT_Protect_Loop @ Examine protect flags again
1583 @ }
1584 TCT_Protect_Available:
1585
1586 @ Protection structure is available.
1587
1588 @ Indicate that this thread owns the protection.
1589 @ protect -> tc_tcb_pointer = TCD_Current_Thread;
1590
1591 STR r3,[r0, #0] @ Indicate calling thread owns this
1592 @ protection
1593
1594 @ Clear the thread waiting flag.
1595 @ protect -> tc_thread_waiting = 0;
1596
1597 MOV r2,#0 @ Clear value
1598 STR r2,[r0, #4] @ Clear the thread waiting flag
1599
1600 @ Save the protection pointer in the thread's control block. Note
1601 @ that both task and HISR threads share the same control block
1602 @ format.
1603 @ REG_Thread_Ptr = (TC_TCB *) TCD_Current_Thread;
1604 @ REG_Thread_Ptr -> tc_current_protect = protect;
1605
1606 STR r0,[r3, #0x38] @ Setup current protection
1607
1608 @ Restore interrupts.
1609
1610 LDR r2,Int_Level @ Pickup address of interrupt level
1611 MRS r1,CPSR @ Pickup current CPSR
1612 LDR r3,[r2, #0] @ Pickup interrupt lockout level
1613 BIC r1,r1,#LOCK_MSK @ Clear lockout bits
1614 ORR r1,r1,r3 @ Build new interrupt lockout
1615 MSR CPSR,r1 @ Setup CPSR appropriately
1616 @ }
1617
1618 TCT_Skip_Protect:
1619
1620 BX r14 @ Return to caller
1621
1622 @}
1623
1624 /*
1625 ************************************************************************
1626 *
1627 * FUNCTION
1628 *
1629 * TCT_Unprotect
1630 *
1631 * DESCRIPTION
1632 *
1633 * This function releases protection of the currently active
1634 * thread. If the caller is not an active thread, then this
1635 * request is ignored.
1636 *
1637 * CALLED BY
1638 *
1639 * Application
1640 * System Components
1641 *
1642 * CALLS
1643 *
1644 * None
1645 *
1646 * INPUTS
1647 *
1648 * None
1649 *
1650 * OUTPUTS
1651 *
1652 * None
1653 *
1654 * HISTORY
1655 *
1656 * NAME DATE REMARKS
1657 *
1658 * W. Lamie 02-15-1994 Created initial version 1.0
1659 * D. Lamie 02-15-1994 Verified version 1.0
1660 *
1661 ************************************************************************
1662 */
1663
1664 @VOID TCT_Unprotect(void)
1665 @{
1666
1667 .globl TCT_Unprotect
1668 TCT_Unprotect:
1669
1670
1671 @ Determine if the caller is in a task or HISR thread.
1672 @ if (TCD_Current_Thread)
1673 @ {
1674
1675 LDR r1,Current_Thread @ Pickup current thread ptr address
1676 LDR r3,[r1, #0] @ Pickup current thread pointer
1677 CMP r3,#0 @ Check to see if it is non-NULL
1678 BEQ TCT_Skip_Unprotect @ If NULL, skip unprotection
1679
1680 @ Setup a thread control block pointer.
1681 @ REG_Thread_Ptr = (TC_TCB *) TCD_Current_Thread;
1682
1683 @ Determine if there is a currently active protection.
1684 @ if (REG_Thread_Ptr -> tc_current_protect)
1685 @ {
1686
1687 LDR r0,[r3, #0x38] @ Pickup current protect field
1688 CMP r0,#0 @ Is there a protection in force?
1689 BEQ TCT_Skip_Unprotect @ If not, nothing is protected
1690
1691 @ Lockout interrupts.
1692
1693 MRS r1,CPSR @ Pickup current CPSR
1694 ORR r1,r1,#LOCKOUT @ Place lockout value in
1695 MSR CPSR,r1 @ Lockout interrupts
1696
1697 @ Yes, this thread still has this protection structure.
1698 @ REG_Protect_Ptr = REG_Thread_Ptr -> tc_current_protect;
1699
1700 @ Is there a higher priority thread waiting for the protection
1701 @ structure?
1702 @ if (REG_Protect_Ptr -> tc_thread_waiting)
1703
1704 LDR r2,[r0, #4] @ Pickup thread waiting flag
1705 CMP r2,#0 @ Are there any threads waiting?
1706 BEQ TCT_Not_Waiting_Unpr @ If not, just release protection
1707
1708 @ Transfer control to the system. Note that this
1709 @ automatically clears the current protection and it returns
1710 @ to the caller of this routine instead of this routine.
1711 @ TCT_Control_To_System();
1712
1713 B TCT_Control_To_System @ Return control to the system
1714
1715 @ else
1716 @ {
1717 TCT_Not_Waiting_Unpr:
1718
1719 @ Clear the protection.
1720 @ REG_Thread_Ptr -> tc_current_protect = NU_NULL;
1721 @ REG_Protect_Ptr -> tc_tcb_pointer = NU_NULL;
1722
1723 MOV r2,#0 @ Build NU_NULL value
1724 STR r2,[r0, #0] @ Release the protection
1725 STR r2,[r3, #0x38] @ Clear protection pointer in the
1726 @ control block
1727
1728 @ }
1729
1730 TCT_Not_Protected:
1731 @ Restore interrupts again.
1732
1733 LDR r2,Int_Level @ Pickup address of interrupt level
1734 MRS r1,CPSR @ Pickup current CPSR
1735 LDR r3,[r2, #0] @ Pickup interrupt lockout level
1736 BIC r1,r1,#LOCK_MSK @ Clear lockout bits
1737 ORR r1,r1,r3 @ Build new interrupt lockout
1738 MSR CPSR,r1 @ Setup CPSR appropriately
1739
1740 @ }
1741 @ }
1742 TCT_Skip_Unprotect:
1743
1744 BX r14 @ Return to caller
1745
1746 @}
1747
1748 /*
1749 ************************************************************************
1750 *
1751 * FUNCTION
1752 *
1753 * TCT_Unprotect_Specific
1754 *
1755 * DESCRIPTION
1756 *
1757 * This function releases a specific protection structure.
1758 *
1759 * CALLED BY
1760 *
1761 * Application
1762 * System Components
1763 *
1764 * CALLS
1765 *
1766 * None
1767 *
1768 * INPUTS
1769 *
1770 * protect Pointer to protection block
1771 *
1772 * OUTPUTS
1773 *
1774 * None
1775 *
1776 * HISTORY
1777 *
1778 * NAME DATE REMARKS
1779 *
1780 * W. Lamie 02-15-1994 Created initial version 1.0
1781 * D. Lamie 02-15-1994 Verified version 1.0
1782 * C. Meredith 03-01-1994 Corrected problem in time-slice
1783 * reset logic, corrected bug
1784 * using protect ptr, resulting
1785 * in version 1.1
1786 * D. Lamie 03-18-1994 Verified version 1.1
1787 *
1788 ************************************************************************
1789 */
1790
1791 @VOID Specific(TC_PROTECT *protect)
1792 @{
1793
1794 .globl TCT_Unprotect_Specific
1795 TCT_Unprotect_Specific:
1796
1797 @ Determine if the caller is in a task or HISR thread.
1798 @ if (TCD_Current_Thread)
1799 @ {
1800
1801 LDR r1,Current_Thread @ Pickup current thread ptr address
1802 LDR r3,[r1, #0] @ Pickup current thread pointer
1803 CMP r3,#0 @ Check to see if it is non-NULL
1804 BEQ TCT_Skip_Unprot_Spec @ If NULL, skip unprotect specific
1805
1806 @ Lockout interrupts.
1807
1808 MRS r1,CPSR @ Pickup current CPSR
1809 ORR r1,r1,#LOCKOUT @ Place lockout value in
1810 MSR CPSR,r1 @ Lockout interrupts
1811
1812 @ Clear the protection pointer.
1813 @ protect -> tc_tcb_pointer = NU_NULL;
1814
1815 MOV r2,#0 @ Build NU_NULL value
1816 STR r2,[r0, #0] @ Clear protection ownership
1817
1818 @ Determine if a thread is waiting.
1819 @ if (protect -> tc_thread_waiting)
1820 @ {
1821
1822 LDR r1,[r0, #4] @ Pickup the waiting field
1823 CMP r1,#0 @ Is there another thread waiting?
1824 BEQ TCT_Not_Waiting_Unspec @ No, restore interrupts and return
1825
1826 @ A higher-priority thread is waiting.
1827
1828 @ Save a minimal context of the thread.
1829
1830 STMDB r13!,{r4-r12,r14} @ Save minimal context of thread on
1831 @ the current stack
1832
1833 #if 1 /* was .if THUMB */
1834 MOV r2,r14 @ Determine what state the caller
1835 MOV r2,r2,LSL #31 @ was in and build an
1836 MOV r2,r2,LSR #26 @ appropriate state mask
1837 STR r2,[r13, #-4]! @ Place it on the stack
1838 #endif
1839
1840 MOV r2,#0 @ Build solicited stack type value
1841 @ and NU_NULL value
1842 STR r2,[r13, #-4]! @ Place it on the top of the stack
1843
1844 @ Setup a pointer to the thread control block.
1845 @ REG_Thread_Ptr = (TC_TCB *) TCD_Current_Thread;
1846
1847 LDR r1,Current_Thread @ Pickup current thread ptr address
1848 LDR r0,[r1, #0] @ Pickup current thread pointer
1849
1850 @ Clear the current thread control block pointer.
1851 @ TCD_Current_Thread = NU_NULL;
1852
1853 LDR r3,Slice_State @ Pickup time slice state address
1854 STR r2,[r1, #0] @ Set current thread pointer to
1855 @ NU_NULL
1856
1857 @ Check to see if a time slice is active. If so, copy the
1858 @ original time slice into the current time slice field of the
1859 @ thread's control block.
1860 @ if (TMD_Time_Slice_State == 0)
1861 @ {
1862
1863 LDR r1,[r3, #0] @ Pickup time slice state flag
1864 CMP r1,#0 @ Compare with active value
1865 BNE TCT_No_Stop_TS_3 @ If non-active, don't disable
1866
1867 @ Insure that the next time the task runs it gets a fresh time
1868 @ slice.
1869 @ REG_Thread_Ptr -> tc_cur_time_slice =
1870 @ REG_Thread_Ptr -> tc_time_slice;
1871
1872 LDR r1,[r0, #0x40] @ Pickup original time slice
1873
1874 @ Clear any active time slice by setting the state to
1875 @ NOT_ACTIVE.
1876 @ TMD_Time_Slice_State = 1;
1877
1878 MOV r2,#1 @ Build disable value
1879 STR r2,[r3, #0] @ Disable time slice
1880 STR r1,[r0, #0x20] @ Reset current time slice
1881 @ }
1882
1883 TCT_No_Stop_TS_3:
1884
1885 @ Save off the current stack pointer in the control block.
1886 @ REG_Thread_Ptr -> tc_stack_pointer = (VOID *) REG_Stack_Ptr;
1887
1888 STR r13,[r0, #0x2c] @ Save the thread's stack pointer
1889
1890 @ Switch to the system stack.
1891 @ REG_Stack_Ptr = TCD_System_Stack;
1892
1893 LDR r1,System_Stack @ Pickup address of stack pointer
1894 LDR r2,System_Limit @ Pickup address of stack limit ptr
1895 LDR r13,[r1, #0] @ Switch to system stack
1896 LDR r10,[r2, #0] @ Setup system stack limit
1897
1898 @ Finished, return to the scheduling loop.
1899
1900 B TCT_Schedule @ Return to scheduling loop
1901
1902 @ }
1903 @ else
1904 @ {
1905 TCT_Not_Waiting_Unspec:
1906
1907 @ No higher-priority thread is waiting.
1908
1909 @ Restore interrupts.
1910
1911 LDR r2,Int_Level @ Pickup address of interrupt level
1912 MRS r1,CPSR @ Pickup current CPSR
1913 LDR r3,[r2, #0] @ Pickup interrupt lockout level
1914 BIC r1,r1,#LOCK_MSK @ Clear lockout bits
1915 ORR r1,r1,r3 @ Build new interrupt lockout
1916 MSR CPSR,r1 @ Setup CPSR appropriately
1917
1918 @ }
1919 @ }
1920
1921 TCT_Skip_Unprot_Spec:
1922
1923 BX r14 @ Return to caller
1924
1925 @}
1926
1927 /*
1928 ************************************************************************
1929 *
1930 * FUNCTION
1931 *
1932 * TCT_Set_Current_Protect
1933 *
1934 * DESCRIPTION
1935 *
1936 * This function sets the current protection field of the current
1937 * thread's control block to the specified protection pointer.
1938 *
1939 * CALLED BY
1940 *
1941 * TCC_Resume_Task Resume task function
1942 *
1943 * CALLS
1944 *
1945 * None
1946 *
1947 * INPUTS
1948 *
1949 * protect Pointer to protection block
1950 *
1951 * OUTPUTS
1952 *
1953 * None
1954 *
1955 * HISTORY
1956 *
1957 * NAME DATE REMARKS
1958 *
1959 * W. Lamie 02-15-1994 Created initial version 1.0
1960 * D. Lamie 02-15-1994 Verified version 1.0
1961 *
1962 ************************************************************************
1963 */
1964
1965 @VOID TCT_Set_Current_Protect(TC_PROTECT *protect)
1966 @{
1967
1968 .globl TCT_Set_Current_Protect
1969 TCT_Set_Current_Protect:
1970
1971 @ Determine if the caller is in a task or HISR thread.
1972 @ if (TCD_Current_Thread)
1973 @ {
1974
1975 LDR r1,Current_Thread @ Pickup current thread ptr address
1976 LDR r3,[r1, #0] @ Pickup current thread pointer
1977 CMP r3,#0 @ Check to see if a thread is
1978 @ active
1979
1980 @ Point at the current thread control block.
1981 @ REG_Thread_Ptr = (TC_TCB *) TCD_Current_Thread;
1982
1983 @ Modify the current protection.
1984 @ REG_Thread_Ptr -> tc_current_protect = protect;
1985
1986 STRNE r0,[r3, #0x38] @ Setup new protection
1987 @ }
1988
1989
1990 BX r14 @ Return to caller
1991
1992 @}
1993
1994 /*
1995 ************************************************************************
1996 *
1997 * FUNCTION
1998 *
1999 * TCT_Protect_Switch
2000 *
2001 * DESCRIPTION
2002 *
2003 * This function waits until a specific task no longer has any
2004 * protection associated with it. This is necessary since task's
2005 * cannot be suspended or terminated unless they have released all
2006 * of their protection.
2007 *
2008 * CALLED BY
2009 *
2010 * System Components
2011 *
2012 * CALLS
2013 *
2014 * None
2015 *
2016 * INPUTS
2017 *
2018 * thread Pointer to thread control blk
2019 *
2020 * OUTPUTS
2021 *
2022 * None
2023 *
2024 * HISTORY
2025 *
2026 * NAME DATE REMARKS
2027 *
2028 * W. Lamie 02-15-1994 Created initial version 1.0
2029 * D. Lamie 02-15-1994 Verified version 1.0
2030 *
2031 ************************************************************************
2032 */
2033
2034 @VOID TCT_Protect_Switch(VOID *thread)
2035 @{
2036
2037 .globl TCT_Protect_Switch
2038 TCT_Protect_Switch:
2039
2040 @ Lockout interrupts.
2041
2042 MRS r1,CPSR @ Pickup current CPSR
2043 ORR r1,r1,#LOCKOUT @ Place lockout value in
2044 MSR CPSR,r1 @ Lockout interrupts
2045
2046 @ REG_Thread_Ptr = (TC_TCB *) thread;
2047
2048 @ Wait until the specified task has no protection associated with it.
2049 @ while (REG_Thread_Ptr -> tc_current_protect)
2050 @ {
2051
2052 LDR r1,[r0, #0x38] @ Pickup protection of specified
2053 @ thread
2054 CMP r1,#0 @ Does the specified thread have
2055 @ an active protection?
2056 BEQ TCT_Switch_Done @ If not, protect switch is done
2057
2058 @ Let the task run again in an attempt to clear its protection.
2059
2060 @ Indicate that a higher priority thread is waiting.
2061 @ (REG_Thread_Ptr -> tc_current_protect) -> tc_thread_waiting = 1;
2062
2063 MOV r2,#1 @ Build waiting flag value
2064 STR r2,[r1, #4] @ Set waiting flag of the
2065 @ protection owned by the other
2066 @ thread
2067
2068 @ Directly schedule the thread waiting.
2069 @ TCT_Schedule_Protected((REG_Thread_Ptr -> tc_current_protect)
2070 @ -> tc_tcb_pointer);
2071
2072 LDR r2,Current_Thread @ Pickup current thread ptr address
2073 STR r0,[r13, #-4]! @ Save r0 on the stack
2074 STR r14,[r13, #-4]! @ Save r14 on the stack
2075 MOV r1,r0 @ Move new thread into r1
2076 LDR r0,[r2, #0] @ Pickup current thread pointer
2077 BL TCT_Schedule_Protected @ Call routine to schedule the
2078 @ owner of the thread
2079
2080 LDR r14,[r13], #4 @ Recover saved r14
2081 LDR r0,[r13], #4 @ Recover saved r0
2082
2083 @ Lockout interrupts.
2084
2085 B TCT_Protect_Switch @ Branch to top of routine and
2086 @ start over
2087 @ }
2088 TCT_Switch_Done:
2089
2090 @ Restore interrupts.
2091
2092 LDR r2,Int_Level @ Pickup address of interrupt level
2093 MRS r1,CPSR @ Pickup current CPSR
2094 LDR r3,[r2, #0] @ Pickup interrupt lockout level
2095 BIC r1,r1,#LOCK_MSK @ Clear lockout bits
2096 ORR r1,r1,r3 @ Build new interrupt lockout
2097 MSR CPSR,r1 @ Setup CPSR appropriately
2098
2099
2100 BX r14 @ Return to caller
2101
2102 @}
2103
2104 /*
2105 ************************************************************************
2106 *
2107 * FUNCTION
2108 *
2109 * TCT_Schedule_Protected
2110 *
2111 * DESCRIPTION
2112 *
2113 * This function saves the minimal context of the thread and then
2114 * directly schedules the thread that has protection over the
2115 * the thread that called this routine.
2116 *
2117 * CALLED BY
2118 *
2119 * TCT_Protect
2120 * TCT_Protect_Switch
2121 *
2122 * CALLS
2123 *
2124 * TCT_Control_To_Thread Transfer control to protected
2125 * thread
2126 *
2127 * INPUTS
2128 *
2129 * None
2130 *
2131 * OUTPUTS
2132 *
2133 * None
2134 *
2135 * HISTORY
2136 *
2137 * NAME DATE REMARKS
2138 *
2139 * W. Lamie 02-15-1994 Created initial version 1.0
2140 * D. Lamie 02-15-1994 Verified version 1.0
2141 * C. Meredith 03-01-1994 Corrected problem in time-slice
2142 * reset logic, resulting in
2143 * version 1.1
2144 * D. Lamie 03-18-1994 Verified version 1.1
2145 *
2146 ************************************************************************
2147 */
2148
2149 @VOID TCT_Schedule_Protected(VOID *thread)
2150 @{
2151
2152 .globl TCT_Schedule_Protected
2153 TCT_Schedule_Protected:
2154
2155 @ Interrupts are already locked out by the caller.
2156
2157 @ Save minimal context required by the system.
2158
2159 STMDB r13!,{r4-r12,r14} @ Save minimal context of thread on
2160 @ the current stack
2161
2162 #if 1 /* was .if THUMB */
2163 MOV r2,r14 @ Determine what state the caller
2164 MOV r2,r2,LSL #31 @ was in and build an
2165 MOV r2,r2,LSR #26 @ appropriate state mask
2166 STR r2,[r13, #-4]! @ Place it on the stack
2167 #endif
2168
2169 MOV r2,#0 @ Build solicited stack type value
2170 @ and NU_NULL value
2171 STR r2,[r13, #-4]! @ Place it on the top of the stack
2172 MOV r4,r1 @ Save thread to schedule
2173
2174 @ Setup a pointer to the thread control block.
2175 @ REG_Thread_Ptr = (TC_TCB *) TCD_Current_Thread;
2176
2177 LDR r1,Current_Thread @ Pickup current thread ptr address
2178
2179 @ Clear the current thread control block.
2180 @ TCD_Current_Thread = NU_NULL;
2181
2182 LDR r3,Slice_State @ Pickup time slice state address
2183 STR r2,[r1, #0] @ Set current thread pointer to
2184 @ NU_NULL
2185
2186 @ Check to see if a time slice is active. If so, copy the original time
2187 @ slice into the current time slice field of the task's control block.
2188 @ if (TMD_Time_Slice_State == 0)
2189 @ {
2190
2191 LDR r1,[r3, #0] @ Pickup time slice state flag
2192 CMP r1,#0 @ Compare with active value
2193 BNE TCT_No_Stop_TS_4 @ If non-active, don't disable
2194
2195 @ Insure that the next time the task runs it gets a fresh time
2196 @ slice.
2197 @ REG_Thread_Ptr -> tc_cur_time_slice = REG_Thread_Ptr -> tc_time_slice;
2198
2199 LDR r1,[r0, #0x40] @ Pickup original time slice
2200
2201 @ Clear any active time slice by setting the state to NOT_ACTIVE.
2202 @ TMD_Time_Slice_State = 1;
2203
2204 MOV r2,#1 @ Build disable value
2205 STR r2,[r3, #0] @ Disable time slice
2206 STR r1,[r0, #0x20] @ Reset current time slice
2207
2208 @ }
2209 TCT_No_Stop_TS_4:
2210
2211 @ Save off the current stack pointer in the control block.
2212 @ REG_Thread_Ptr -> tc_stack_pointer = (VOID *) REG_Stack_Ptr;
2213
2214 STR r13,[r0, #0x2c] @ Save the thread's stack pointer
2215
2216 @ Switch to the system stack.
2217 @ TCD_System_Stack = (VOID *) REG_Stack_Ptr;
2218
2219 LDR r1,System_Stack @ Pickup address of stack pointer
2220 LDR r2,System_Limit @ Pickup address of stack limit ptr
2221 LDR r13,[r1, #0] @ Switch to system stack
2222 LDR r10,[r2, #0] @ Setup system stack limit
2223
2224 @ Transfer control to the specified thread directly.
2225 @ TCT_Control_To_Thread(thread);
2226
2227 LDR r2,Int_Level @ Pickup address of interrupt level
2228 MRS r1,CPSR @ Pickup current CPSR
2229 LDR r3,[r2, #0] @ Pickup interrupt lockout level
2230 BIC r1,r1,#LOCK_MSK @ Clear lockout bits
2231 ORR r1,r1,r3 @ Build new interrupt lockout
2232 MOV r0,r4 @ Indicate thread to schedule
2233 MSR CPSR,r1 @ Setup CPSR appropriately
2234 ORR r1,r1,#LOCKOUT @ Build lockout value again
2235 MSR CPSR,r1 @ Lockout interrupts again
2236 B TCT_Control_To_Thread @ Schedule the thread indirectly
2237 @}
2238
2239 /*
2240 ************************************************************************
2241 *
2242 * FUNCTION
2243 *
2244 * TCT_Interrupt_Context_Save
2245 *
2246 * DESCRIPTION
2247 *
2248 * This function saves the interrupted thread's context. Nested
2249 * interrupts are also supported. If a task or HISR thread was
2250 * interrupted, the stack pointer is switched to the system stack
2251 * after the context is saved.
2252 *
2253 * CALLED BY
2254 *
2255 * Application ISRs Assembly language ISRs
2256 * INT_Interrupt_Shell Interrupt handler shell
2257 *
2258 * CALLS
2259 *
2260 * None
2261 *
2262 * INPUTS
2263 *
2264 * vector Interrupt's vector number
2265 *
2266 * OUTPUTS
2267 *
2268 * None
2269 *
2270 * HISTORY
2271 *
2272 * NAME DATE REMARKS
2273 *
2274 * W. Lamie 02-15-1994 Created initial version 1.0
2275 * D. Lamie 02-15-1994 Verified version 1.0
2276 * D. Driscoll 01-04-2002 Released version 1.13.3.
2277 * Updated to handle nested /
2278 * prioritized IRQs
2279 ************************************************************************
2280 */
2281
2282 @VOID TCT_Interrupt_Context_Save(INT vector)
2283 @{
2284
2285 .globl TCT_Interrupt_Context_Save
2286 TCT_Interrupt_Context_Save:
2287 @ Determine if this is a nested interrupt.
2288 LDR r1,Int_Count @ Pickup address of interrupt count
2289 LDR r2,[r1, #0] @ Pickup interrupt counter
2290 ADD r2,r2,#1 @ Add 1 to interrupt counter
2291 STR r2,[r1, #0] @ Store new interrupt counter value
2292 CMP r2,#1 @ Is it nested?
2293 BEQ TCT_Not_Nested_Save @ No
2294
2295 @ Nested interrupt. Save complete context on the current stack.
2296 TCT_Nested_Save:
2297
2298 /* No longer needed in the FreeCalypso version, as we can use r0 instead. */
2299 #if 0
2300 @ 1. Save another register on the exception stack so we have enough to work with
2301 STMDB r13!,{r5}
2302 #endif
2303
2304 @ 2. Save the necessary exception registers into r1-r3
2305 MOV r1,r13 @ Put the exception r13 into r1
2306 MOV r2,r14 @ Move the return address for the caller
2307 @ of this function into r2
2308 MRS r3,spsr @ Put the exception spsr into r3
2309
2310 @ 3. Adjust the exception stack pointer for future exceptions
2311 ADD r13,r13,#20 @ r13 reset to pre-interrupt value
2312
2313 @ 4. Switch CPU modes to save context on system stack
2314 MRS r0,CPSR @ Pickup the current CPSR
2315 BIC r0,r0,#MODE_MASK @ Clear the mode bits
2316
2317 ORR r0,r0,#SUP_MODE @ Change to supervisor mode (SVD)
2318
2319 MSR CPSR,r0 @ Switch modes (IRQ->SVC)
2320
2321 @ 5. Store the SVC r13 into r5 so the r13 can be saved as is.
2322 @ FreeCalyspo: using r0 instead
2323 MOV r0,r13
2324
2325 @ 6. Save the exception return address on the stack (r15).
2326 STMDB r0!,{r4}
2327
2328 @ 7. Save r5-r14 on stack (used to be r6-r14)
2329 STMDB r0!,{r5-r14}
2330
2331 @ 8. Switch back to using r13 now that the original r13 has been saved.
2332 MOV r13,r0
2333
2334 /* no longer relevant */
2335 #if 0
2336 @ 9. Get r5 and exception enable registers off of exception stack and
2337 @ save r5 (stored in r4) back to the system stack.
2338 LDMIA r1!,{r4-r5}
2339 STMDB r13!,{r4}
2340 MOV r4,r5 @ Put exception enable value into r4
2341 #endif
2342
2343 @ 10. Get the rest of the registers off the exception stack and
2344 @ save them onto the system stack.
2345 LDMIA r1!,{r5-r8,r11} @ Get r0-r4 off exception stack
2346 STMDB r13!,{r5-r8,r11} @ Put r0-r4 on system stack
2347
2348 /* no longer relevant */
2349 #if 0
2350 @ 11. Store the exception enable value back on the exception stack.
2351 STMDB r1,{r4}
2352 #endif
2353
2354 @ 12. Save the SPSR on the system stack (CPSR)
2355 STMDB r13!,{r3}
2356
2357 /* TI's approach to interrupt handling does not support re-enabling here */
2358 #if 0
2359 @ 13. Re-enable interrupts
2360 MRS r1,CPSR
2361 BIC r1,r1,#(IRQ_BIT_OR_FIQ_BIT)
2362 MSR CPSR,r1
2363 #endif
2364
2365 BX r2 @ Return to calling ISR
2366 @ }
2367 @ else
2368 @ {
2369 TCT_Not_Nested_Save:
2370
2371 @ Determine if a thread was interrupted.
2372 @ if (TCD_Current_Thread)
2373 @ {
2374
2375 LDR r1,Current_Thread @ Pickup current thread ptr address
2376 LDR r1,[r1, #0] @ Pickup the current thread pointer
2377 CMP r1,#0 @ Is it NU_NULL?
2378 BEQ TCT_Idle_Context_Save @ If no, no real save is necessary
2379
2380
2381 @ Yes, a thread was interrupted. Save complete context on the
2382 @ thread's stack.
2383
2384 /* No longer needed in the FreeCalypso version, as we can use r0 instead. */
2385 #if 0
2386 @ 1. Save another register on the exception stack so we have enough to work with
2387 STMDB r13!,{r5}
2388 #endif
2389
2390 @ 2. Save the necessary exception registers into r1-r3
2391 MOV r1,r13 @ Put the exception r13 into r1
2392 MOV r2,r14 @ Move the return address for the caller
2393 @ of this function into r2
2394 MRS r3,spsr @ Put the exception spsr into r3
2395
2396 @ 3. Adjust the exception stack pointer for future exceptions
2397 ADD r13,r13,#20 @ r13 reset to pre-interrupt value
2398
2399 @ 4. Switch CPU modes to save context on system stack
2400 MRS r0,CPSR @ Pickup the current CPSR
2401 BIC r0,r0,#MODE_MASK @ Clear the mode bits
2402
2403 ORR r0,r0,#SUP_MODE @ Change to supervisor mode (SVD)
2404
2405 MSR CPSR,r0 @ Switch modes (IRQ->SVC)
2406
2407 @ 5. Store the SVC r13 into r5 so the r13 can be saved as is.
2408 @ FreeCalyspo: using r0 instead
2409 MOV r0,r13
2410
2411 @ 6. Save the exception return address on the stack (r15).
2412 STMDB r0!,{r4}
2413
2414 @ 7. Save r5-r14 on stack (used to be r6-r14)
2415 STMDB r0!,{r5-r14}
2416
2417 @ 8. Switch back to using r13 now that the original r13 has been saved.
2418 MOV r13,r0
2419
2420 /* no longer relevant */
2421 #if 0
2422 @ 9. Get r5 and exception enable registers off of exception stack and
2423 @ save r5 (stored in r4) back to the system stack.
2424 LDMIA r1!,{r4-r5}
2425 STMDB r13!,{r4}
2426 MOV r4,r5 @ Put exception enable value into r4
2427 #endif
2428
2429 @ 10. Get the rest of the registers off the exception stack and
2430 @ save them onto the system stack.
2431 LDMIA r1!,{r5-r8,r11} @ Get r0-r4 off exception stack
2432 STMDB r13!,{r5-r8,r11} @ Put r0-r4 on system stack
2433
2434 /* no longer relevant */
2435 #if 0
2436 @ 11. Store the exception enable value back on the exception stack.
2437 STMDB r1,{r4}
2438 #endif
2439
2440 @ 12. Save the SPSR on the system stack (CPSR)
2441 STMDB r13!,{r3}
2442
2443 @ 13. Save stack type to the task stack (1=interrupt stack)
2444 MOV r1,#1 @ Interrupt stack type
2445 STMDB r13!,{r1}
2446
2447 @ Save the thread's stack pointer in the control block.
2448 @ REG_Thread_Ptr = (TC_TCB *) TCD_Current_Thread
2449 @ REG_Thread_Ptr -> tc_stack_pointer = (VOID *) REG_Stack_Ptr
2450
2451 LDR r1,Current_Thread @ Pickup current thread ptr address
2452 LDR r3,[r1, #0] @ Pickup current thread pointer
2453 STR r13,[r3, #TC_STACK_POINTER] @ Save stack pointer
2454
2455 @ Switch to the system stack.
2456 @ REG_Stack_Ptr = TCD_System_Stack
2457
2458 LDR r1,System_Stack @ Pickup address of stack pointer
2459 LDR r3,System_Limit @ Pickup address of stack limit ptr
2460 LDR r13,[r1, #0] @ Switch to system stack
2461 LDR r10,[r3, #0] @ Setup system stack limit
2462
2463 /* TI's approach to interrupt handling does not support re-enabling here */
2464 #if 0
2465 @ Re-enable interrupts
2466 MRS r1,CPSR
2467 BIC r1,r1,#(IRQ_BIT_OR_FIQ_BIT)
2468 MSR CPSR,r1
2469 #endif
2470
2471 @ Return to caller ISR.
2472
2473 BX r2 @ Return to caller ISR
2474
2475 @ }
2476
2477 TCT_Idle_Context_Save:
2478
2479 MOV r2,r14 @ Save r14 in r2
2480 @ LDR r3,[r13] @ Get exception enable value from stack
2481 ADD r13,r13,#20 @ Adjust exception r13 for future interrupts
2482 @ STR r3,[r13] @ Put exception enable value back on stack
2483
2484 MRS r1,CPSR @ Pickup current CPSR
2485 BIC r1,r1,#MODE_MASK @ Clear the current mode
2486 @ BIC r1,r1,#(IRQ_BIT_OR_FIQ_BIT) @ Re-enable interrupts
2487
2488 ORR r1,r1,#SUP_MODE @ Prepare to switch to supervisor
2489 @ mode (SVC)
2490 MSR CPSR,r1 @ Switch to supervisor mode (SVC)
2491
2492 BX r2 @ Return to caller ISR
2493
2494 @ }
2495 @}
2496
2497 /*
2498 ************************************************************************
2499 *
2500 * FUNCTION
2501 *
2502 * TCT_Interrupt_Context_Restore
2503 *
2504 * DESCRIPTION
2505 *
2506 * This function restores the interrupt context if a nested
2507 * interrupt condition is present. Otherwise, this routine
2508 * transfers control to the scheduling function.
2509 *
2510 * CALLED BY
2511 *
2512 * Application ISRs Assembly language ISRs
2513 * INT_Interrupt_Shell Interrupt handler shell
2514 *
2515 * CALLS
2516 *
2517 * TCT_Schedule Thread scheduling function
2518 *
2519 * INPUTS
2520 *
2521 * None
2522 *
2523 * OUTPUTS
2524 *
2525 * None
2526 *
2527 * HISTORY
2528 *
2529 * NAME DATE REMARKS
2530 *
2531 * W. Lamie 02-15-1994 Created initial version 1.0
2532 * D. Lamie 02-15-1994 Verified version 1.0
2533 * D. Driscoll 01-04-2002 Released version 1.13.3.
2534 * Updated to handle nested /
2535 * prioritized IRQs
2536 *
2537 ************************************************************************
2538 */
2539
2540 @VOID TCT_Interrupt_Context_Restore(void)
2541 @{
2542
2543 .globl TCT_Interrupt_Context_Restore
2544 TCT_Interrupt_Context_Restore:
2545 @ It is assumed that anything pushed on the stack by ISRs has been
2546 @ removed upon entry into this routine.
2547
2548 @ Decrement and check for nested interrupt conditions.
2549 @ if (--TCD_Interrupt_Count)
2550 @ {
2551
2552 LDR r1,Int_Count @ Pickup address of interrupt count
2553 LDR r2,[r1, #0] @ Pickup interrupt counter
2554 SUB r2,r2,#1 @ Decrement interrupt counter
2555 STR r2,[r1, #0] @ Store interrupt counter
2556 CMP r2,#0
2557 BEQ TCT_Not_Nested_Restore
2558
2559 @ Restore previous context.
2560
2561 LDR r1,[r13], #4 @ Pickup the saved CPSR
2562
2563 MSR SPSR,r1 @ Place into saved SPSR
2564 LDMIA r13,{r0-r15}^ @ Return to the point of interrupt
2565
2566 @ }
2567 @ else
2568 @ {
2569
2570 TCT_Not_Nested_Restore:
2571
2572 @ Determine if a thread is active.
2573 @ if (TCD_Current_Thread)
2574 @ {
2575
2576 LDR r1,Current_Thread @ Pickup current thread ptr address
2577 LDR r0,[r1, #0] @ Pickup current thread pointer
2578 CMP r0,#0 @ Determine if a thread is active
2579 BEQ TCT_Idle_Context_Restore @ If not, idle system restore
2580
2581 @ Clear the current thread pointer.
2582 @ TCD_Current_Thread = NU_NULL
2583
2584 MOV r2,#0 @ Build NU_NULL value
2585 STR r2,[r1, #0] @ Set current thread ptr to NU_NULL
2586
2587 @ Determine if a time slice is active. If so, the remaining
2588 @ time left on the time slice must be saved in the task's
2589 @ control block.
2590 @ if (TMD_Time_Slice_State == 0)
2591 @ {
2592
2593 LDR r3,Slice_State @ Pickup time slice state address
2594 LDR r1,[r3, #0] @ Pickup time slice state
2595 CMP r1,#0 @ Determine if time slice active
2596 BNE TCT_Idle_Context_Restore @ If not, skip time slice reset
2597
2598 @ Pickup the remaining portion of the time slice and save it
2599 @ in the task's control block.
2600 @ REG_Thread_Ptr -> tc_cur_time_slice = TMD_Time_Slice
2601 @ TMD_Time_Slice_State = 1
2602
2603 LDR r2,Time_Slice @ Pickup address of time slice left
2604 MOV r1,#1 @ Build disable time slice value
2605 LDR r2,[r2, #0] @ Pickup remaining time slice
2606 STR r1,[r3, #0] @ Disable time slice
2607 STR r2,[r0, #TC_CUR_TIME_SLICE] @ Store remaining time slice
2608
2609 @ }
2610 @ }
2611 TCT_Idle_Context_Restore:
2612
2613 @ Reset the system stack pointer.
2614 LDR r1,System_Stack @ Pickup address of stack pointer
2615 LDR r2,System_Limit @ Pickup address of stack limit ptr
2616 LDR r13,[r1, #0] @ Switch to system stack
2617 LDR r10,[r2, #0] @ Setup system stack limit
2618
2619 @ Return to scheduler.
2620
2621 B TCT_Schedule @ Return to scheduling loop
2622
2623 @ }
2624 @}
2625
2626 /*
2627 ************************************************************************
2628 *
2629 * FUNCTION
2630 *
2631 * TCT_Activate_HISR
2632 *
2633 * DESCRIPTION
2634 *
2635 * This function activates the specified HISR. If the HISR is
2636 * already activated, the HISR's activation count is simply
2637 * incremented. Otherwise, the HISR is placed on the appropriate
2638 * HISR priority list in preparation for execution.
2639 *
2640 * CALLED BY
2641 *
2642 * Application LISRs
2643 *
2644 * CALLS
2645 *
2646 * None
2647 *
2648 * INPUTS
2649 *
2650 * hisr Pointer to HISR to activate
2651 *
2652 * OUTPUTS
2653 *
2654 * NU_SUCCESS Successful completion
2655 *
2656 * HISTORY
2657 *
2658 * NAME DATE REMARKS
2659 *
2660 * W. Lamie 02-15-1994 Created initial version 1.0
2661 * D. Lamie 02-15-1994 Verified version 1.0
2662 *
2663 ************************************************************************
2664 */
2665
2666 @STATUS TCT_Activate_HISR(TC_HCB *hisr)
2667 @{
2668
2669 .globl TCT_Activate_HISR
2670 TCT_Activate_HISR:
2671
2672 @INT priority;
2673
2674
2675 @ Lockout interrupts.
2676
2677 STR r4,[r13, #-4]! @ Save r4
2678 MRS r4,CPSR @ Pickup current CPSR
2679 ORR r1,r4,#LOCKOUT @ Build interrupt lockout value
2680 MSR CPSR,r1 @ Lockout interrupts
2681
2682 @ Determine if the HISR is already active.
2683 @ if (hisr -> tc_activation_count)
2684 @ {
2685
2686 LDR r1,[r0,#0x40] @ Pickup current activation count
2687 CMP r1,#0 @ Is it the first activation?
2688 BEQ TCT_First_Activate @ Yes, place it on the correct list
2689
2690 @ Increment the activation count. Make sure that it does not go
2691 @ to zero.
2692 @ hisr -> tc_activation_count++;
2693
2694 ADDS r1,r1,#1 @ Increment the activation count
2695 STR r1,[r0,#0x40] @ Store new activation count
2696
2697 @ if (hisr -> tc_activation_count == 0)
2698
2699 @ hisr -> tc_activation_count = 0xFFFFFFFFUL;
2700
2701 MVNEQ r1,#0 @ If counter rolled-over reset
2702 STREQ r1,[r0,#0x40] @ Store all ones count
2703 B TCT_Activate_Done @ Finished with activation
2704 @ }
2705 @ else
2706 @ {
2707 TCT_First_Activate:
2708
2709
2710 @ Set the activation count to 1.
2711 @ hisr -> tc_activation_count = 1;
2712
2713 MOV r1,#1 @ Initial activation count
2714 STR r1,[r0,#0x40] @ Store initial activation count
2715
2716 @ Pickup the HISR's priority.
2717 @ priority = hisr -> tc_priority;
2718
2719 @ Determine if there is something in the given priority list.
2720 @ if (TCD_Active_HISR_Tails[priority])
2721 @ {
2722
2723 LDRB r1,[r0,#0x1a] @ Pickup priority of HISR
2724 LDR r2,HISR_Tails @ Pickup tail pointer base
2725 LDR r3,[r2,r1,LSL #2] @ Pickup tail pointer for priority
2726 CMP r3,#0 @ Is this first HISR at priority?
2727 BEQ TCT_First_HISR @ No, append to end of HISR list
2728
2729 @ Something is already on this list. Add after the tail.
2730 @ (TCD_Active_HISR_Tails[priority]) -> tc_active_next = hisr;
2731 @ TCD_Active_HISR_Tails[priority] = hisr;
2732
2733 STR r0,[r3,#0x3c] @ Setup the active next pointer
2734 STR r0,[r2,r1,LSL #2] @ Setup the tail pointer
2735 B TCT_Activate_Done @ Finished with activate processing
2736 @ }
2737 @ else
2738 @ {
2739 TCT_First_HISR:
2740
2741 @ Nothing is on this list.
2742 @ TCD_Active_HISR_Heads[priority] = hisr;
2743 @ TCD_Active_HISR_Tails[priority] = hisr;
2744
2745 LDR r3,HISR_Heads @ Pickup address of head pointers
2746 STR r0,[r2,r1,LSL #2] @ Set tail pointer to this HISR
2747 STR r0,[r3,r1,LSL #2] @ Set head pointer to this HISR
2748
2749 @ Determine the highest priority HISR.
2750 @ if (TCD_Active_HISR_Heads[0])
2751 @ TCD_Execute_HISR = TCD_Active_HISR_Heads[0];
2752 @ else if (TCD_Active_HISR_Heads[1])
2753 @ TCD_Execute_HISR = TCD_Active_HISR_Heads[1];
2754 @ else
2755 @ TCD_Execute_HISR = TCD_Active_HISR_Heads[2];
2756
2757 LDR r1,[r3,#0] @ Pickup priority 0 head pointer
2758 LDR r0,Execute_HISR @ Build address to execute HISR ptr
2759 CMP r1,#0 @ Is priority 0 active?
2760 LDREQ r1,[r3,#4] @ If not, pickup priority 1 head
2761 CMPEQ r1,#0 @ Is priority 1 active?
2762 LDREQ r1,[r3,#8] @ Else, must be priority 2 active
2763 STR r1,[r0,#0] @ Store which ever priority is the
2764 @ active one
2765 @ }
2766 @ }
2767 TCT_Activate_Done:
2768
2769 MSR CPSR,r4 @ Restore interrupt lockout
2770 LDR r4,[r13], #4 @ Restore corrupted r4
2771
2772 @ return(NU_SUCCESS);
2773
2774 MOV r0,#0 @ Always return NU_SUCCESS
2775
2776 BX r14 @ Return to caller
2777
2778 @}
2779
2780 /*
2781 ************************************************************************
2782 *
2783 * FUNCTION
2784 *
2785 * TCT_HISR_Shell
2786 *
2787 * DESCRIPTION
2788 *
2789 * This function is the execution shell of each and every HISR. If
2790 * the HISR has completed its processing, this shell routine exits
2791 * back to the system. Otherwise, it sequentially calls the HISR
2792 * routine until the activation count goes to zero.
2793 *
2794 * CALLED BY
2795 *
2796 * HISR Scheduling
2797 *
2798 * CALLS
2799 *
2800 * hisr -> tc_entry Actual entry function of HISR
2801 *
2802 * INPUTS
2803 *
2804 * None
2805 *
2806 * OUTPUTS
2807 *
2808 * None
2809 *
2810 * HISTORY
2811 *
2812 * NAME DATE REMARKS
2813 *
2814 * W. Lamie 02-15-1994 Created initial version 1.0
2815 * D. Lamie 02-15-1994 Verified version 1.0
2816 *
2817 ************************************************************************
2818 */
2819
2820 @VOID TCT_HISR_Shell(void)
2821 @{
2822 .globl TCT_HISR_Shell
2823 TCT_HISR_Shell:
2824
2825 @ Point at the HISR.
2826 @ REG_HISR_Ptr = (TC_HCB *) TCD_Current_Thread;
2827
2828 LDR r0,Current_Thread @ Build address of thread pointer
2829 LDR r5,[r0, #0] @ Pickup control block pointer
2830
2831 @ do
2832 @ {
2833 TCT_HISR_Loop:
2834
2835 @ Call the HISR's entry routine.
2836 @ (*(REG_HISR_Ptr -> tc_entry)) ();
2837
2838 /* old TMS470 code:
2839
2840 .if THUMB = 0
2841
2842 MOV r14,r15 ; Setup return value
2843 LDR r15,[r5,#44h] ; Call HISR entry function
2844 .else
2845 LDR r4,[r5,#44h] ; Get HISR entry function
2846 TST r4,#1 ; See if calling Thumb or ARM
2847 BNE Thumbsec
2848 MOV r14,r15 ; Setup return value
2849 BX r4
2850 B ARMCODE
2851 Thumbsec:
2852 ADD r14, r15, #1
2853 BX r4
2854 .state16
2855 ThumbAfterHisr
2856 MOV r1, r15
2857 BX r1
2858 .state32
2859 .endif
2860 */
2861
2862 /* new code for the GNU style of ARM/Thumb interworking */
2863 ldr r4, [r5, #TC_HISR_ENTRY]
2864 mov lr, pc
2865 bx r4
2866
2867 @ Lockout interrupts.
2868
2869 MRS r1,CPSR @ Pickup current CPSR
2870 ORR r1,r1,#LOCKOUT @ Build interrupt lockout
2871 MSR CPSR,r1 @ Lockout interrupts
2872
2873 @ On return, decrement the activation count and check to see if
2874 @ it is 0. Once it reaches 0, the HISR should be made inactive.
2875 @ REG_HISR_Ptr -> tc_activation_count--;
2876
2877
2878 LDR r0,[r5, #0x40] @ Pickup current activation count
2879 SUBS r0,r0,#1 @ Subtract and set condition codes
2880 STR r0,[r5, #0x40] @ Store new activation count
2881 BEQ TCT_HISR_Finished @ Finished processing HISR
2882
2883 @ Restore interrupts.
2884
2885 LDR r2,Int_Level @ Pickup address of interrupt level
2886 MRS r1,CPSR @ Pickup current CPSR
2887 LDR r3,[r2, #0] @ Pickup interrupt lockout level
2888 BIC r1,r1,#LOCK_MSK @ Clear lockout bits
2889 ORR r1,r1,r3 @ Build new interrupt lockout
2890 MSR CPSR,r1 @ Setup CPSR appropriately
2891 B TCT_HISR_Loop @ Return to HISR loop
2892 @ }
2893 @ while (REG_HISR_Ptr -> tc_activation_count);
2894
2895 TCT_HISR_Finished:
2896
2897 @ At this point, the HISR needs to be made inactive.
2898
2899 @ Determine if this is the only HISR on the given priority list.
2900 @ if (REG_HISR_Ptr == TCD_Active_HISR_Tails[REG_HISR_Ptr -> tc_priority])
2901 @ {
2902
2903 LDR r14,HISR_Tails @ Pickup tail pointers address
2904 LDRB r3,[r5,#0x1a] @ Pickup priority
2905 LDR r6,[r14,r3,LSL #2] @ Pickup this priority tail pointer
2906 LDR r2,Execute_HISR @ Build address to execute HISR ptr
2907 MOV r12,#0 @ Clear r12
2908 LDR r1,HISR_Heads @ Pickup head pointers address
2909 CMP r6,r5 @ Is this priority tail the same as
2910 @ the current HISR?
2911 BNE TCT_More_HISRs @ If not, more HISRs at this
2912 @ priority
2913
2914 @ The only HISR on the list. Clean up the list and check for the
2915 @ highest priority HISR.
2916 @ TCD_Active_HISR_Heads[REG_HISR_Ptr -> tc_priority] = NU_NULL;
2917 @ TCD_Active_HISR_Tails[REG_HISR_Ptr -> tc_priority] = NU_NULL;
2918
2919 STR r12,[r1,r3,LSL #2] @ Set head pointer to NU_NULL
2920 STR r12,[r14,r3,LSL #2] @ Set tail pointer to NU_NULL
2921
2922 @ Determine the highest priority HISR.
2923 @ if (TCD_Active_HISR_Heads[0])
2924 @ TCD_Execute_HISR = TCD_Active_HISR_Heads[0];
2925 @ else if (TCD_Active_HISR_Heads[1])
2926 @ TCD_Execute_HISR = TCD_Active_HISR_Heads[1];
2927 @ else
2928 @ TCD_Execute_HISR = TCD_Active_HISR_Heads[2];
2929
2930 LDR r3,[r1,#0] @ Pickup priority 0 head pointer
2931 CMP r3,#0 @ Is there an HISR active?
2932 LDREQ r3,[r1,#4] @ If not, pickup priority 1 pointer
2933 CMPEQ r3,#0 @ Is there an HISR active?
2934 LDREQ r3,[r1,#8] @ If not, pickup priority 2 pointer
2935 STR r3,[r2,#0] @ Setup execute HISR pointer
2936 B TCT_HISR_Exit @ Exit HISR processing
2937 @ }
2938 @ else
2939 @ {
2940
2941 TCT_More_HISRs:
2942
2943 @ Move the head pointer to the next HISR in the list.
2944 @ TCD_Active_HISR_Heads[REG_HISR_Ptr -> tc_priority] =
2945 @ REG_HISR_Ptr -> tc_active_next;
2946
2947 @ Also set the TCD_Execute_HISR pointer.
2948 @ TCD_Execute_HISR = REG_HISR_Ptr -> tc_active_next;
2949
2950 LDR r14,[r5,#0x3c] @ Pickup next HISR to activate
2951 STR r14,[r1,r3,LSL #2] @ Setup new head pointer
2952 STR r14,[r2, #0] @ Setup execute HISR pointer
2953 @ }
2954
2955 TCT_HISR_Exit:
2956
2957 @ Build fake return to the top of this loop. The next time the HISR
2958 @ is activated, it will return to the top of this function.
2959
2960 LDR r14,HISR_Shell @ Pickup address of shell entry
2961 STMDB r13!,{r4-r12,r14} @ Save minimal context of thread on
2962 @ the current stack
2963 MOV r2,#0 @ Build solicited stack type value
2964 @ and NU_NULL value
2965 #if 1 /* was .if THUMB */
2966 STR r2,[r13, #-4]! @ Save state mask
2967 #endif
2968 STR r2,[r13, #-4]! @ Place it on the top of the stack
2969
2970 @ Clear the current thread control block.
2971 @ TCD_Current_Thread = NU_NULL;
2972
2973 LDR r1,Current_Thread @ Pickup current thread ptr address
2974 STR r2,[r1, #0] @ Set current thread pointer to
2975 @ NU_NULL
2976
2977 @ Save off the current stack pointer in the control block.
2978 @ REG_HISR_Ptr -> tc_stack_pointer = (VOID *) REG_Stack_Ptr;
2979
2980
2981 STR r13,[r5, #0x2c] @ Save the thread's stack pointer
2982
2983
2984 @ Switch to the system stack.
2985 @ REG_Stack_Ptr = (BYTE_PTR) TCD_System_Stack;
2986
2987 LDR r1,System_Stack @ Pickup address of stack pointer
2988 LDR r2,System_Limit @ Pickup address of stack limit ptr
2989 LDR r13,[r1, #0] @ Switch to system stack
2990 LDR r10,[r2, #0] @ Setup system stack limit
2991
2992 @ Transfer control to the main scheduling loop.
2993
2994 B TCT_Schedule @ Return to main scheduling loop
2995 @}
2996
2997 /* FreeCalypso addition, used by riviera/rvf/rvf_task.c: */
2998 .globl INT_Check_IRQ_Mask
2999 INT_Check_IRQ_Mask:
3000 MRS r0,CPSR
3001 BX lr
3002