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
|
/*
ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio.
This file is part of ChibiOS.
ChibiOS 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 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 PPC/chcore.c
* @brief PowerPC architecture port code.
*
* @addtogroup PPC_CORE
* @{
*/
#include "ch.h"
/*===========================================================================*/
/* Module local definitions. */
/*===========================================================================*/
/*===========================================================================*/
/* Module exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local types. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Module exported functions. */
/*===========================================================================*/
/**
* @brief Performs a context switch between two threads.
* @details This is the most critical code in any port, this function
* is responsible for the context switch between 2 threads.
* @note The implementation of this code affects <b>directly</b> the context
* switch performance so optimize here as much as you can.
*/
#if !defined(__DOXYGEN__)
__attribute__((naked))
#endif
void port_dummy1(void) {
asm (".global _port_switch");
asm ("_port_switch:");
asm ("subi %sp, %sp, 80"); /* Size of the intctx structure. */
asm ("mflr %r0");
asm ("stw %r0, 84(%sp)"); /* LR into the caller frame. */
asm ("mfcr %r0");
asm ("stw %r0, 0(%sp)"); /* CR. */
asm ("stmw %r14, 4(%sp)"); /* GPR14...GPR31. */
asm ("stw %sp, 12(%r4)"); /* Store swapped-out stack. */
asm ("lwz %sp, 12(%r3)"); /* Load swapped-in stack. */
asm ("lmw %r14, 4(%sp)"); /* GPR14...GPR31. */
asm ("lwz %r0, 0(%sp)"); /* CR. */
asm ("mtcr %r0");
asm ("lwz %r0, 84(%sp)"); /* LR from the caller frame. */
asm ("mtlr %r0");
asm ("addi %sp, %sp, 80"); /* Size of the intctx structure. */
asm ("blr");
}
/**
* @brief Start a thread by invoking its work function.
* @details If the work function returns @p chThdExit() is automatically
* invoked.
*/
#if !defined(__DOXYGEN__)
__attribute__((naked))
#endif
void port_dummy2(void) {
asm (".global _port_thread_start");
asm ("_port_thread_start:");
chSysUnlock();
asm ("mr %r3, %r31"); /* Thread parameter. */
asm ("mtctr %r30");
asm ("bctrl"); /* Invoke thread function. */
asm ("bl chThdExit"); /* Thread termination on exit. */
}
/** @} */
|
