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
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
|
/*
* FreeRTOS Kernel V10.3.0
* Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* http://www.FreeRTOS.org
* http://aws.amazon.com/freertos
*
* 1 tab == 4 spaces!
*/
#include "FreeRTOSConfig.h"
.extern pxCurrentTCB
.extern vTaskSwitchContext
.extern xTaskIncrementTick
.extern vPortISRHandler
.global vPortStartFirstTask
.global vPortYield
.global vPortTickISR
.global vPortISRWrapper
.global vPortSaveFPURegisters
.global vPortRestoreFPURegisters
.set BChainField, 0
.set NextLRField, BChainField + 4
.set MSRField, NextLRField + 4
.set PCField, MSRField + 4
.set LRField, PCField + 4
.set CTRField, LRField + 4
.set XERField, CTRField + 4
.set CRField, XERField + 4
.set USPRG0Field, CRField + 4
.set r0Field, USPRG0Field + 4
.set r2Field, r0Field + 4
.set r3r31Field, r2Field + 4
.set IFrameSize, r3r31Field + ( ( 31 - 3 ) + 1 ) * 4
.macro portSAVE_STACK_POINTER_AND_LR
/* Get the address of the TCB. */
xor R0, R0, R0
addis R2, R0, pxCurrentTCB@ha
lwz R2, pxCurrentTCB@l( R2 )
/* Store the stack pointer into the TCB */
stw SP, 0( R2 )
/* Save the link register */
stwu R1, -24( R1 )
mflr R0
stw R31, 20( R1 )
stw R0, 28( R1 )
mr R31, r1
.endm
.macro portRESTORE_STACK_POINTER_AND_LR
/* Restore the link register */
lwz R11, 0( R1 )
lwz R0, 4( R11 )
mtlr R0
lwz R31, -4( R11 )
mr R1, R11
/* Get the address of the TCB. */
xor R0, R0, R0
addis SP, R0, pxCurrentTCB@ha
lwz SP, pxCurrentTCB@l( R1 )
/* Get the task stack pointer from the TCB. */
lwz SP, 0( SP )
.endm
vPortStartFirstTask:
/* Get the address of the TCB. */
xor R0, R0, R0
addis SP, R0, pxCurrentTCB@ha
lwz SP, pxCurrentTCB@l( SP )
/* Get the task stack pointer from the TCB. */
lwz SP, 0( SP )
/* Restore MSR register to SRR1. */
lwz R0, MSRField(R1)
mtsrr1 R0
/* Restore current PC location to SRR0. */
lwz R0, PCField(R1)
mtsrr0 R0
/* Save USPRG0 register */
lwz R0, USPRG0Field(R1)
mtspr 0x100,R0
/* Restore Condition register */
lwz R0, CRField(R1)
mtcr R0
/* Restore Fixed Point Exception register */
lwz R0, XERField(R1)
mtxer R0
/* Restore Counter register */
lwz R0, CTRField(R1)
mtctr R0
/* Restore Link register */
lwz R0, LRField(R1)
mtlr R0
/* Restore remaining GPR registers. */
lmw R3,r3r31Field(R1)
/* Restore r0 and r2. */
lwz R0, r0Field(R1)
lwz R2, r2Field(R1)
/* Remove frame from stack */
addi R1,R1,IFrameSize
/* Return into the first task */
rfi
vPortYield:
portSAVE_STACK_POINTER_AND_LR
bl vTaskSwitchContext
portRESTORE_STACK_POINTER_AND_LR
blr
vPortTickISR:
portSAVE_STACK_POINTER_AND_LR
bl xTaskIncrementTick
#if configUSE_PREEMPTION == 1
bl vTaskSwitchContext
#endif
/* Clear the interrupt */
lis R0, 2048
mttsr R0
portRESTORE_STACK_POINTER_AND_LR
blr
vPortISRWrapper:
portSAVE_STACK_POINTER_AND_LR
bl vPortISRHandler
portRESTORE_STACK_POINTER_AND_LR
blr
#if configUSE_FPU == 1
vPortSaveFPURegisters:
/* Enable APU and mark FPU as present. */
mfmsr r0
xor r30, r30, r30
oris r30, r30, 512
ori r30, r30, 8192
or r0, r0, r30
mtmsr r0
#ifdef USE_DP_FPU
/* Buffer address is in r3. Save each flop register into an offset from
this buffer address. */
stfd f0, 0(r3)
stfd f1, 8(r3)
stfd f2, 16(r3)
stfd f3, 24(r3)
stfd f4, 32(r3)
stfd f5, 40(r3)
stfd f6, 48(r3)
stfd f7, 56(r3)
stfd f8, 64(r3)
stfd f9, 72(r3)
stfd f10, 80(r3)
stfd f11, 88(r3)
stfd f12, 96(r3)
stfd f13, 104(r3)
stfd f14, 112(r3)
stfd f15, 120(r3)
stfd f16, 128(r3)
stfd f17, 136(r3)
stfd f18, 144(r3)
stfd f19, 152(r3)
stfd f20, 160(r3)
stfd f21, 168(r3)
stfd f22, 176(r3)
stfd f23, 184(r3)
stfd f24, 192(r3)
stfd f25, 200(r3)
stfd f26, 208(r3)
stfd f27, 216(r3)
stfd f28, 224(r3)
stfd f29, 232(r3)
stfd f30, 240(r3)
stfd f31, 248(r3)
/* Also save the FPSCR. */
mffs f31
stfs f31, 256(r3)
#else
/* Buffer address is in r3. Save each flop register into an offset from
this buffer address. */
stfs f0, 0(r3)
stfs f1, 4(r3)
stfs f2, 8(r3)
stfs f3, 12(r3)
stfs f4, 16(r3)
stfs f5, 20(r3)
stfs f6, 24(r3)
stfs f7, 28(r3)
stfs f8, 32(r3)
stfs f9, 36(r3)
stfs f10, 40(r3)
stfs f11, 44(r3)
stfs f12, 48(r3)
stfs f13, 52(r3)
stfs f14, 56(r3)
stfs f15, 60(r3)
stfs f16, 64(r3)
stfs f17, 68(r3)
stfs f18, 72(r3)
stfs f19, 76(r3)
stfs f20, 80(r3)
stfs f21, 84(r3)
stfs f22, 88(r3)
stfs f23, 92(r3)
stfs f24, 96(r3)
stfs f25, 100(r3)
stfs f26, 104(r3)
stfs f27, 108(r3)
stfs f28, 112(r3)
stfs f29, 116(r3)
stfs f30, 120(r3)
stfs f31, 124(r3)
/* Also save the FPSCR. */
mffs f31
stfs f31, 128(r3)
#endif
blr
#endif /* configUSE_FPU. */
#if configUSE_FPU == 1
vPortRestoreFPURegisters:
/* Enable APU and mark FPU as present. */
mfmsr r0
xor r30, r30, r30
oris r30, r30, 512
ori r30, r30, 8192
or r0, r0, r30
mtmsr r0
#ifdef USE_DP_FPU
/* Buffer address is in r3. Restore each flop register from an offset
into this buffer.
First the FPSCR. */
lfs f31, 256(r3)
mtfsf f31, 7
lfd f0, 0(r3)
lfd f1, 8(r3)
lfd f2, 16(r3)
lfd f3, 24(r3)
lfd f4, 32(r3)
lfd f5, 40(r3)
lfd f6, 48(r3)
lfd f7, 56(r3)
lfd f8, 64(r3)
lfd f9, 72(r3)
lfd f10, 80(r3)
lfd f11, 88(r3)
lfd f12, 96(r3)
lfd f13, 104(r3)
lfd f14, 112(r3)
lfd f15, 120(r3)
lfd f16, 128(r3)
lfd f17, 136(r3)
lfd f18, 144(r3)
lfd f19, 152(r3)
lfd f20, 160(r3)
lfd f21, 168(r3)
lfd f22, 176(r3)
lfd f23, 184(r3)
lfd f24, 192(r3)
lfd f25, 200(r3)
lfd f26, 208(r3)
lfd f27, 216(r3)
lfd f28, 224(r3)
lfd f29, 232(r3)
lfd f30, 240(r3)
lfd f31, 248(r3)
#else
/* Buffer address is in r3. Restore each flop register from an offset
into this buffer.
First the FPSCR. */
lfs f31, 128(r3)
mtfsf f31, 7
lfs f0, 0(r3)
lfs f1, 4(r3)
lfs f2, 8(r3)
lfs f3, 12(r3)
lfs f4, 16(r3)
lfs f5, 20(r3)
lfs f6, 24(r3)
lfs f7, 28(r3)
lfs f8, 32(r3)
lfs f9, 36(r3)
lfs f10, 40(r3)
lfs f11, 44(r3)
lfs f12, 48(r3)
lfs f13, 52(r3)
lfs f14, 56(r3)
lfs f15, 60(r3)
lfs f16, 64(r3)
lfs f17, 68(r3)
lfs f18, 72(r3)
lfs f19, 76(r3)
lfs f20, 80(r3)
lfs f21, 84(r3)
lfs f22, 88(r3)
lfs f23, 92(r3)
lfs f24, 96(r3)
lfs f25, 100(r3)
lfs f26, 104(r3)
lfs f27, 108(r3)
lfs f28, 112(r3)
lfs f29, 116(r3)
lfs f30, 120(r3)
lfs f31, 124(r3)
#endif
blr
#endif /* configUSE_FPU. */
|