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
|
/************************************************************************************
* arch/sh/src/m16c/m16c_head.S
*
* Copyright (C) 2009, 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 "chip.h"
#include "up_internal.h"
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
/************************************************************************************
* Macro Definitions
************************************************************************************/
/*****************************************************************************
* Name: showprogress
*
* Description:
* Print a character on the UART to show boot status.
*
*****************************************************************************/
.macro showprogress, code
#ifdef CONFIG_DEBUG
.globl _up_lowputc
mov.b r#\code1l /* Character to print */
jsr.a _up_lowputc /* Print it */
#endif
.endm
/************************************************************************************
* Data
************************************************************************************/
/* The near RAM memory map is as follows:
*
* 0x00400 - DATA Size: Determined by linker
* BSS Size: Determined by linker
* Interrupt stack Size: CONFIG_ARCH_INTERRUPTSTACK
* Idle stack Size: CONFIG_IDLETHREAD_STACKSIZE
* Heap Size: Everything remaining
* 0x00bff - (end+1)
*/
.section .rodata
.globl _g_snbss
.type _g_snbss, object
_g_snbss:
.word _g_snbss
.size _g_snbss, .-_g_snbss
.globl _g_enbss
.type _g_enbss, object
_g_enbss:
.word _g_enbss
.size _g_enbss, .-_g_enbss
.globl _g_sndata
.type _g_sndata, object
_g_sndata:
.word _g_sndata
.size _g_sndata, .-_g_sndata
.globl _g_endata
.type _g_endata, object
_g_endata:
.word _g_endata
.size _g_endata, .-_g_endata
.globl _g_enronly
.type _g_enronly, object
_g_enronly:
.long _g_enronly
.size _g_enronly, .-_g_efronly
#ifdef CONFIG_M16C_HAVEFARRAM
.globl _g_sfbss
.type _g_sfbss, object
_g_sfbss:
.long _g_sfbss
.size _g_sfbss, .-_g_sfbss
.globl _g_efbss
.type _g_efbss, object
_g_efbss:
.long _g_efbss
.size _g_efbss, .-_g_efbss
.globl _g_sfdata
.type _g_sfdata, object
_g_sfdata:
.long _g_sfdata
.size _g_sfdata, .-_g_sfdata
.globl _g_efdata
.type _g_efdata, object
_g_efdata:
.long _g_efdata
.size _g_efdata, .-_g_efdata
.globl _g_efronly
.type _g_efronly, object
_g_efronly:
.long _g_efronly
.size _g_efronly, .-_g_efronly
#endif
.globl _g_svarvect
.type _g_svarvect, object
_g_svarvect:
.long _svarvect
.size _g_svarvect, .-_g_svarvect
.globl _g_idle_topstack
.type _g_idle_topstack, object
_g_idle_topstack:
.long _enbss+CONFIG_ARCH_INTERRUPTSTACK+CONFIG_IDLETHREAD_STACKSIZE
.size _g_idle_topstack, .-_g_idle_topstack
/************************************************************************************
* Code
************************************************************************************/
/************************************************************************************
* Name: __start
*
* Description:
* After reset, program execution starts here.
*
************************************************************************************/
.text
.globl __start
.globl _enbss
.type __start, #function
__start:
/* Set the interrupt and user stack pointers */
mov.w #_enbss, R0
ldc R0, isp /* Set the interrupt stack pointer to the end of BSS */
add.w #CONFIG_IDLETHREAD_STACKSIZE, R0
fset U /* Set bit 7 (U) to select the user stack pointer */
ldc R0, sp /* Set the user stack pointer */
/* Set BCLK speed. At reset, the processor clock (BLCK) defaults to a divisor of 8.
* This sets clock to F1 (divide by 1) on XIN: BCLK = XIN frequency.
*/
mov.b #0x01, M16C_PRCR /* Unprotect CM0 to change clock setting */
mov.b #0x08, M16C_CM0 /* enable CM17 and CM16 to set BCLK to F1
* CM17 & CM16 defaults to 0 after reset and
* so we only need to reset CM06 to 0 */
mov.b #0x00,M16C_PRCR /* protect CM0 */
/* The two MS bits of the interrupt cause select register must be set to
* enable the use of INT4 and INT5
*/
mov.b #0xc0, M16C_IFSR /* Set b7 & b6 if application will use INT4 & INT5 */
ldc #M16C_IRAM_BASE, sb /* Set sb register (to what?) */
/* Set up INTB to point to location of variable vector table */
mov.w _g_svarvect, r0 /* R0 = lower 16-bits */
mov.w _g_svarvect+2, r1 /* R1 = upper 4-bits */
ldc r1, intbh
ldc r0, intbl
/* Configure the uart so that we can get debug output as soon as possible. */
.globl _up_lowsetup /* Early initialization of UART */
jsr.a _up_lowsetup
showprogress 'A'
/* Clear near .bss sections */
mov.b #0x00, r0l /* r0l: 0 */
mov.w _g_snbss, a1 /* a1: start of near .bss */
mov.w _g_enbss, r3 /* r3: end of near .bss */
sub.w a1, r3 /* r3: size of near .bss */
sstr.b /* Clear near .bss */
/* Clear far .bss sections */
showprogress 'B'
#ifdef CONFIG_M16C_HAVEFARRAM
# warning "Far RAM support not implemented"
#endif
/* Initialize near .data sections (.rodata is not moved) */
mov.w _g_enronly, a0 /* a0: Low 16 bits of source address */
mov.b _g_enronly+2, r1h /* 4 MS of 20-bit source address */
mov.w _g_sndata, a1 /* a1: start of near .data */
mov.w _g_endata, r3 /* r3: end of near .data */
sub.w a1, r3 /* r3: size of near .data */
smovf.b /* Copy source to near .data */
/* Initialize far .data sections (.rodata is not moved) */
showprogress 'C'
#ifdef CONFIG_M16C_HAVEFARRAM
# warning "Far RAM support not implemented"
#endif
/* Perform early console initialization */
#ifdef USE_EARLYSERIALINIT
.globl _up_earlyconsoleinit /* Early initialization of console driver */
jsr.a _up_earlyconsoleinit /* Call it */
showprogress 'D'
#endif
/* Call C++ constructors */
#ifdef CONFIG_CPLUSPLUS
# warning "No C++ support yet"
showprogress 'E'
#endif
/* Initialize onboard LEDs */
#ifdef CONFIG_ARCH_LEDS
.globl _up_ledinit /* Boot LED setup */
jsr.a _up_ledinit /* Call it */
#endif
showprogress '\n'
/* Pass control to NuttX */
.globl _os_start
jsr.a _os_start
/* NuttX will not return, but just in case... */
_os_exit:
jmp.s _os_exit
.size __start, .-__start
.end
|
