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
|
/*
ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file ports/AVR/chcore.h
* @brief AVR architecture port macros and structures.
* @addtogroup AVR_CORE
* @{
*/
#ifndef _CHCORE_H_
#define _CHCORE_H_
#include <avr/io.h>
#include <avr/interrupt.h>
/**
* If enabled allows the idle thread to enter a low power mode.
*/
#ifndef ENABLE_WFI_IDLE
#define ENABLE_WFI_IDLE 0
#endif
/**
* Macro defining the AVR architecture.
*/
#define CH_ARCHITECTURE_AVR
/**
* 8 bit stack alignment.
*/
typedef uint8_t stkalign_t;
/** @cond never */
/**
* Interrupt saved context.
* @note The field @p _next is not part of the context, it represents the
* offset of the structure relative to the stack pointer.
*/
struct extctx {
uint8_t _next;
uint8_t r31;
uint8_t r30;
uint8_t r27;
uint8_t r26;
uint8_t r25;
uint8_t r24;
uint8_t r23;
uint8_t r22;
uint8_t r21;
uint8_t r20;
uint8_t r19;
uint8_t r18;
uint8_t sr;
uint8_t r1;
uint8_t r0;
uint16_t pc;
};
/** @endcond */
/** @cond never */
/**
* System saved context.
* @note The field @p _next is not part of the context, it represents the
* offset of the structure relative to the stack pointer.
*/
struct intctx {
uint8_t _next;
uint8_t r29;
uint8_t r28;
uint8_t r17;
uint8_t r16;
uint8_t r15;
uint8_t r14;
uint8_t r13;
uint8_t r12;
uint8_t r11;
uint8_t r10;
#ifndef CH_CURRP_REGISTER_CACHE
uint8_t r9;
uint8_t r8;
#endif
uint8_t r7;
uint8_t r6;
uint8_t r5;
uint8_t r4;
uint8_t r3;
uint8_t r2;
uint8_t pcl;
uint8_t pch;
};
/** @endcond */
/** @cond never */
/**
* In the AVR port this structure just holds a pointer to the @p intctx
* structure representing the stack pointer at the time of the context switch.
*/
struct context {
struct intctx *sp;
};
/** @endcond */
/**
* Platform dependent part of the @p chThdInit() API.
* This code usually setup the context switching frame represented by a
* @p intctx structure.
*/
#define SETUP_CONTEXT(workspace, wsize, pf, arg) { \
tp->p_ctx.sp = (struct intctx*)((uint8_t *)workspace + wsize - \
sizeof(struct intctx)); \
tp->p_ctx.sp->r2 = (int)pf; \
tp->p_ctx.sp->r3 = (int)pf >> 8; \
tp->p_ctx.sp->r4 = (int)arg; \
tp->p_ctx.sp->r5 = (int)arg >> 8; \
tp->p_ctx.sp->pcl = (int)threadstart >> 8; \
tp->p_ctx.sp->pch = (int)threadstart; \
}
/**
* The default idle thread implementation requires no extra stack space in
* this port.
*/
#ifndef IDLE_THREAD_STACK_SIZE
#define IDLE_THREAD_STACK_SIZE 8
#endif
/**
* Per-thread stack overhead for interrupts servicing, it is used in the
* calculation of the correct working area size. In this port the default is
* 32 bytes per thread.
*/
#ifndef INT_REQUIRED_STACK
#define INT_REQUIRED_STACK 32
#endif
/**
* Enforces a correct alignment for a stack area size value.
*/
#define STACK_ALIGN(n) ((((n) - 1) | sizeof(stkalign_t)) + 1)
/**
* Computes the thread working area global size.
*/
#define THD_WA_SIZE(n) STACK_ALIGN(sizeof(Thread) + \
(sizeof(struct intctx) - 1) + \
(sizeof(struct extctx) - 1) + \
(n) + (INT_REQUIRED_STACK))
/**
* Macro used to allocate a thread working area aligned as both position and
* size.
*/
#define WORKING_AREA(s, n) stkalign_t s[THD_WA_SIZE(n) / sizeof(stkalign_t)];
/**
* IRQ prologue code, inserted at the start of all IRQ handlers enabled to
* invoke system APIs.
* This code tricks the compiler to save all the specified registers by
* "touching" them.
*/
#define PORT_IRQ_PROLOGUE() { \
asm ("" : : : "r18", "r19", "r20", "r21", "r22", "r23", "r24", \
"r25", "r26", "r27", "r30", "r31"); \
}
/**
* IRQ epilogue code, inserted at the end of all IRQ handlers enabled to
* invoke system APIs.
*/
#define PORT_IRQ_EPILOGUE() { \
if (chSchRescRequiredI()) \
chSchDoRescheduleI(); \
}
/**
* IRQ handler function declaration. Note, it just aliases the WinAVR "ISR"
* macro.
*/
#define PORT_IRQ_HANDLER(id) ISR(id)
/**
* This function is empty in this port.
*/
#define port_init()
/**
* Implemented as global interrupt disable.
*/
#define port_lock() asm volatile ("cli")
/**
* Implemented as global interrupt enable.
*/
#define port_unlock() asm volatile ("sei")
/**
* This function is empty in this port.
*/
#define port_lock_from_isr()
/**
* This function is empty in this port.
*/
#define port_unlock_from_isr()
/**
* Implemented as global interrupt disable.
*/
#define port_disable() asm volatile ("cli")
/**
* Same as @p port_disable() in this port, there is no difference between the
* two states.
*/
#define port_suspend() asm volatile ("cli")
/**
* Implemented as global interrupt enable.
*/
#define port_enable() asm volatile ("sei")
/**
* This port function is implemented as inlined code for performance reasons.
*/
#if ENABLE_WFI_IDLE != 0
#define port_wait_for_interrupt() { \
asm volatile ("sleep"); \
}
#else
#define port_wait_for_interrupt()
#endif
#ifdef __cplusplus
extern "C" {
#endif
void port_puts(char *msg);
void port_switch(Thread *otp, Thread *ntp);
void port_halt(void);
void threadstart(void);
#ifdef __cplusplus
}
#endif
#endif /* _CHCORE_H_ */
/** @} */
|
