chcore.h
10.7 KB
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
/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012 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/>.
---
A special exception to the GPL can be applied should you wish to distribute
a combined work that includes ChibiOS/RT, without being obliged to provide
the source code for any proprietary components. See the file exception.txt
for full details of how and when the exception can be applied.
*/
/**
* @file 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 CH_DBG_ENABLE_STACK_CHECK
#error "option CH_DBG_ENABLE_STACK_CHECK not supported by this port"
#endif
/**
* @brief If enabled allows the idle thread to enter a low power mode.
*/
#ifndef ENABLE_WFI_IDLE
#define ENABLE_WFI_IDLE 0
#endif
/**
* @brief Macro defining the AVR architecture.
*/
#define CH_ARCHITECTURE_AVR
/**
* @brief Name of the implemented architecture.
*/
#define CH_ARCHITECTURE_NAME "AVR"
/**
* @brief Name of the architecture variant (optional).
*/
#define CH_CORE_VARIANT_NAME "MegaAVR"
/**
* @brief Name of the compiler supported by this port.
*/
#define CH_COMPILER_NAME "GCC " __VERSION__
/**
* @brief Port-specific information string.
*/
#define CH_PORT_INFO "None"
/**
* @brief 8 bits stack and memory alignment enforcement.
*/
typedef uint8_t stkalign_t;
/**
* @brief Interrupt saved context.
* @details This structure represents the stack frame saved during a
* preemption-capable interrupt handler.
* @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;
};
/**
* @brief System saved context.
* @details This structure represents the inner stack frame during a context
* switching.
* @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;
uint8_t r9;
uint8_t r8;
uint8_t r7;
uint8_t r6;
uint8_t r5;
uint8_t r4;
uint8_t r3;
uint8_t r2;
uint8_t pcl;
uint8_t pch;
};
/**
* @brief Platform dependent part of the @p Thread structure.
* @details 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;
};
/**
* @brief Platform dependent part of the @p chThdCreateI() API.
* @details This code usually setup the context switching frame represented
* by an @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)_port_thread_start >> 8; \
tp->p_ctx.sp->pch = (int)_port_thread_start; \
}
/**
* @brief Stack size for the system idle thread.
* @details This size depends on the idle thread implementation, usually
* the idle thread should take no more space than those reserved
* by @p PORT_INT_REQUIRED_STACK.
* @note In this port it is set to 8.
*/
#ifndef PORT_IDLE_THREAD_STACK_SIZE
#define PORT_IDLE_THREAD_STACK_SIZE 8
#endif
/**
* @brief Per-thread stack overhead for interrupts servicing.
* @details This constant is used in the calculation of the correct working
* area size.
* This value can be zero on those architecture where there is a
* separate interrupt stack and the stack space between @p intctx and
* @p extctx is known to be zero.
* @note In this port the default is 32 bytes per thread.
*/
#ifndef PORT_INT_REQUIRED_STACK
#define PORT_INT_REQUIRED_STACK 32
#endif
/**
* @brief Enforces a correct alignment for a stack area size value.
*/
#define STACK_ALIGN(n) ((((n) - 1) | (sizeof(stkalign_t) - 1)) + 1)
/**
* @brief 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) + (PORT_INT_REQUIRED_STACK))
/**
* @brief Static working area allocation.
* @details This macro is used to allocate a static thread working area
* aligned as both position and size.
*/
#define WORKING_AREA(s, n) stkalign_t s[THD_WA_SIZE(n) / sizeof(stkalign_t)]
/**
* @brief IRQ prologue code.
* @details This macro must be inserted at the start of all IRQ handlers
* enabled to invoke system APIs.
* @note 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"); \
}
/**
* @brief IRQ epilogue code.
* @details This macro must be inserted at the end of all IRQ handlers
* enabled to invoke system APIs.
*/
#define PORT_IRQ_EPILOGUE() { \
dbg_check_lock(); \
if (chSchIsPreemptionRequired()) \
chSchDoReschedule(); \
dbg_check_unlock(); \
}
/**
* @brief IRQ handler function declaration.
* @note @p id can be a function name or a vector number depending on the
* port implementation.
*/
#define PORT_IRQ_HANDLER(id) ISR(id)
/**
* @brief Port-related initialization code.
* @note This function is empty in this port.
*/
#define port_init()
/**
* @brief Kernel-lock action.
* @details Usually this function just disables interrupts but may perform more
* actions.
* @note Implemented as global interrupt disable.
*/
#define port_lock() asm volatile ("cli" : : : "memory")
/**
* @brief Kernel-unlock action.
* @details Usually this function just enables interrupts but may perform more
* actions.
* @note Implemented as global interrupt enable.
*/
#define port_unlock() asm volatile ("sei" : : : "memory")
/**
* @brief Kernel-lock action from an interrupt handler.
* @details This function is invoked before invoking I-class APIs from
* interrupt handlers. The implementation is architecture dependent,
* in its simplest form it is void.
* @note This function is empty in this port.
*/
#define port_lock_from_isr()
/**
* @brief Kernel-unlock action from an interrupt handler.
* @details This function is invoked after invoking I-class APIs from interrupt
* handlers. The implementation is architecture dependent, in its
* simplest form it is void.
* @note This function is empty in this port.
*/
#define port_unlock_from_isr()
/**
* @brief Disables all the interrupt sources.
* @note Of course non-maskable interrupt sources are not included.
* @note Implemented as global interrupt disable.
*/
#define port_disable() asm volatile ("cli" : : : "memory")
/**
* @brief Disables the interrupt sources below kernel-level priority.
* @note Interrupt sources above kernel level remains enabled.
* @note Same as @p port_disable() in this port, there is no difference
* between the two states.
*/
#define port_suspend() asm volatile ("cli" : : : "memory")
/**
* @brief Enables all the interrupt sources.
* @note Implemented as global interrupt enable.
*/
#define port_enable() asm volatile ("sei" : : : "memory")
/**
* @brief Enters an architecture-dependent IRQ-waiting mode.
* @details The function is meant to return when an interrupt becomes pending.
* The simplest implementation is an empty function or macro but this
* would not take advantage of architecture-specific power saving
* modes.
* @note This port function is implemented as inlined code for performance
* reasons.
*/
#if ENABLE_WFI_IDLE != 0
#define port_wait_for_interrupt() { \
asm volatile ("sleep" : : : "memory"); \
}
#else
#define port_wait_for_interrupt()
#endif
#ifdef __cplusplus
extern "C" {
#endif
void port_switch(Thread *ntp, Thread *otp);
void port_halt(void);
void _port_thread_start(void);
#ifdef __cplusplus
}
#endif
#endif /* _CHCORE_H_ */
/** @} */