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
|
/****************************************************************************
* arch/arm/src/common/up_createstack.c
*
* Copyright (C) 2007-2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <sched.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/arch.h>
#include <arch/board/board.h>
#include "up_arch.h"
#include "up_internal.h"
/****************************************************************************
* Pre-processor Macros
****************************************************************************/
/* ARM requires at least a 4-byte stack alignment. For use with EABI and
* floating point, the stack must be aligned to 8-byte addresses.
*/
#ifndef CONFIG_STACK_ALIGNMENT
/* The symbol __ARM_EABI__ is defined by GCC if EABI is being used. If you
* are not using GCC, make sure that CONFIG_STACK_ALIGNMENT is set correctly!
*/
# ifdef __ARM_EABI__
# define CONFIG_STACK_ALIGNMENT 8
# else
# define CONFIG_STACK_ALIGNMENT 4
# endif
#endif
/* Stack alignment macros */
#define STACK_ALIGN_MASK (CONFIG_STACK_ALIGNMENT-1)
#define STACK_ALIGN_DOWN(a) ((a) & ~STACK_ALIGN_MASK)
#define STACK_ALIGN_UP(a) (((a) + STACK_ALIGN_MASK) & ~STACK_ALIGN_MASK)
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Name: memset32
*
* On most larger then 8 bit archs this will need to be word aligned so
* so maybe some checks should be put in place?
*
****************************************************************************/
#if defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_STACK)
static void *memset32(void *s, uint32_t c, size_t n)
{
uint32_t *p = (uint32_t *)s;
while (n-- > 0) *p++ = c;
return s;
}
#endif
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Name: up_create_stack
*
* Description:
* Allocate a stack for a new thread and setup up stack-related
* information in the TCB.
*
* The following TCB fields must be initialized:
* adj_stack_size: Stack size after adjustment for hardware, processor,
* etc. This value is retained only for debug purposes.
* stack_alloc_ptr: Pointer to allocated stack
* adj_stack_ptr: Adjusted stack_alloc_ptr for HW. The initial value of
* the stack pointer.
*
* Input Parameters:
* tcb: The TCB of new task
* stack_size: The requested stack size. At least this how much must be
* allocated.
*
****************************************************************************/
int up_create_stack(struct tcb_s *tcb, size_t stack_size)
{
/* Is there already a stack allocated of a different size? */
if (tcb->stack_alloc_ptr && tcb->adj_stack_size != stack_size)
{
/* Yes.. free it */
sched_free(tcb->stack_alloc_ptr);
tcb->stack_alloc_ptr = NULL;
}
/* Do we need to allocate a stack? */
if (!tcb->stack_alloc_ptr)
{
/* Allocate the stack. If DEBUG is enabled (but not stack debug),
* then create a zeroed stack to make stack dumps easier to trace.
*/
#if defined(CONFIG_DEBUG) && !defined(CONFIG_DEBUG_STACK)
tcb->stack_alloc_ptr = (uint32_t *)kzalloc(stack_size);
#else
tcb->stack_alloc_ptr = (uint32_t *)kmalloc(stack_size);
#endif
#ifdef CONFIG_DEBUG
if (!tcb->stack_alloc_ptr)
{
sdbg("ERROR: Failed to allocate stack, size %d\n", stack_size);
}
#endif
}
/* Did we successfully allocate a stack? */
if (tcb->stack_alloc_ptr)
{
size_t top_of_stack;
size_t size_of_stack;
/* The ARM uses a push-down stack: the stack grows toward lower
* addresses in memory. The stack pointer register, points to
* the lowest, valid work address (the "top" of the stack). Items
* on the stack are referenced as positive word offsets from sp.
*/
top_of_stack = (uint32_t)tcb->stack_alloc_ptr + stack_size - 4;
/* The ARM stack must be aligned; 4 byte alignment for OABI and
* 8-byte alignment for EABI. If necessary top_of_stack must be
* rounded down to the next boundary
*/
top_of_stack = STACK_ALIGN_DOWN(top_of_stack);
/* The size of the stack in bytes is then the difference between
* the top and the bottom of the stack (+4 because if the top
* is the same as the bottom, then the size is one 32-bit element).
* The size need not be aligned.
*/
size_of_stack = top_of_stack - (uint32_t)tcb->stack_alloc_ptr + 4;
/* Save the adjusted stack values in the struct tcb_s */
tcb->adj_stack_ptr = (uint32_t*)top_of_stack;
tcb->adj_stack_size = size_of_stack;
/* If stack debug is enabled, then fill the stack with a
* recognizable value that we can use later to test for high
* water marks.
*/
#if defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_STACK)
memset32(tcb->stack_alloc_ptr, 0xDEADBEEF, tcb->adj_stack_size/4);
#endif
up_ledon(LED_STACKCREATED);
return OK;
}
return ERROR;
}
|