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
|
/**************************************************************************
* arch/arm/src/lpc2378/lpc23xx_lowputc.S
*
* Copyright (C) 2010 Rommel Marcelo. All rights reserved.
* Author: Rommel Marcelo
*
* This file is part of the NuttX RTOS and based on the lpc2148 port:
*
* Copyright (C) 2010 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 "up_internal.h"
#include "up_arch.h"
#include "lpc23xx_pinsel.h"
#include "lpc23xx_scb.h"
#include "lpc23xx_uart.h"
/**************************************************************************
* Private Definitions
**************************************************************************/
@ //-- Pins
@ PINSEL0 |= (0x01<<4) | //-- P0.2 TXD0
@ (0x01<<6); //-- P0.3 RXD0
@PCLKSEL0 |= (0x01 << 6); //-- bit 7:6 =01-> Clock div = 1 for UART0
#if defined(CONFIG_UART0_SERIAL_CONSOLE)
# define UARTxBASE UART0_BASE_ADDR
# define PINSELECT LPC23XX_PINSEL0
# define UARTxPCLKSEL 0xE01FC1A8
# define PCLKSEL_MASK U0_PCLKSEL_MASK
# define UARTxPINSEL UART0_PINSEL
# define UARTxPINMASK UART0_PINMASK
# define UARTxBAUD CONFIG_UART0_BAUD
# define UARTxBITS CONFIG_UART0_BITS
# define UARTxPARITY CONFIG_UART0_PARITY
# define UARTx2STOP CONFIG_UART0_2STOP
#elif defined(CONFIG_UART1_SERIAL_CONSOLE)
# define UARTxBASE UART1_BASE_ADDR
/* # define PINSELECT LPC23XX_PINSEL1 only Uart0/Uart2 share same Pinsel */
# define UARTxPCLKSEL 0xE01FC1A8
# define PCLKSEL_MASK U1_PCLKSEL_MASK
# define UARTxPINSEL UART1_PINSEL
# define UARTxPINMASK UART1_PINMASK
# define UARTxBAUD CONFIG_UART1_BAUD
# define UARTxBITS CONFIG_UART1_BITS
# define UARTxPARITY CONFIG_UART1_PARITY
# define UARTx2STOP CONFIG_UART1_2STOP
#elif defined(CONFIG_UART2_SERIAL_CONSOLE)
# define UARTxBASE UART2_BASE_ADDR
# define PINSELECT LPC23XX_PINSEL0
# define UARTxPCLKSEL 0xE01FC1AC
# define PCLKSEL_MASK U2_PCLKSEL_MASK
# define UARTxPINSEL UART2_PINSEL
# define UARTxPINMASK UART2_PINMASK
# define UARTxBAUD CONFIG_UART2_BAUD
# define UARTxBITS CONFIG_UART2_BITS
# define UARTxPARITY CONFIG_UART2_PARITY
# define UARTx2STOP CONFIG_UART2_2STOP
#elif defined(CONFIG_UART3_SERIAL_CONSOLE)
# define PINSELECT LPC23XX_PINSEL0
# define UARTxBASE UART3_BASE_ADDR
# define UARTxPCLKSEL 0xE01FC1AC
# define PCLKSEL_MASK U2_PCLKSEL_MASK
# define UARTxPINSEL UART3_PINSEL
# define UARTxPINMASK UART3_PINMASK
# define UARTxBAUD CONFIG_UART3_BAUD
# define UARTxBITS CONFIG_UART3_BITS
# define UARTxPARITY CONFIG_UART3_PARITY
# define UARTx2STOP CONFIG_UART3_2STOP
#else
# error "No CONFIG_UARTn_SERIAL_CONSOLE Setting"
#endif
#if UARTxBITS == 5
# define LCR_CHAR LCR_CHAR_5
#elif UARTxBITS == 6
# define LCR_CHAR LCR_CHAR_6
#elif UARTxBITS == 7
# define LCR_CHAR LCR_CHAR_7
#elif UARTxBITS == 8
# define LCR_CHAR LCR_CHAR_8
#else
# error "No CONFIG_UARTn_BITS Setting"
#endif
#if UARTxPARITY == 0
# define LCR_PAR LCR_PAR_NONE
#elif UARTxPARITY == 1
# define LCR_PAR LCR_PAR_ODD
#elif UARTxPARITY == 2
# define LCR_PAR LCR_PAR_EVEN
#elif UARTxPARITY == 3
# define LCR_PAR LCR_PAR_MARK
#elif UARTxPARITY == 4
# define LCR_PAR LCR_PAR_SPACE
#else
# error "No CONFIG_UARTn_PARITY Setting"
#endif
#if UARTx2STOP != 0
# define LCR_STOP LCR_STOP_2
#else
# define LCR_STOP LCR_STOP_1
#endif
#define LCR_VALUE (LCR_CHAR | LCR_PAR | LCR_STOP)
#define FCR_VALUE (FCR_FIFO_TRIG8 | FCR_TX_FIFO_RESET | \
FCR_RX_FIFO_RESET | FCR_FIFO_ENABLE)
@#define MULVAL (12 << 4)
@#define DIVADDVAL 3
/**************************************************************************
* Private Types
**************************************************************************/
/**************************************************************************
* Private Function Prototypes
**************************************************************************/
/**************************************************************************
* Global Variables
**************************************************************************/
/**************************************************************************
* Private Variables
**************************************************************************/
/**************************************************************************
* Private Functions
**************************************************************************/
/**************************************************************************
* Public Functions
**************************************************************************/
/**************************************************************************
* Name: up_lowputc
**************************************************************************/
/* This assembly language version has the advantage that it does not
* require a C stack and uses only r0-r1. Hence it can be used during
* early boot phases.
*/
.text
.global up_lowputc
.type up_lowputc, function
up_lowputc:
/* On entry, r0 holds the character to be printed */
ldr r1, =UARTxBASE
strb r0, [r1, #UART_THR_OFFSET]
/* Wait for the byte to be transferred */
1: ldr r0, [r1, #UART_LSR_OFFSET]
ands r0, #LSR_TEMT /* Transmitter empty */
beq 1b
/* And return */
mov pc, lr
.size up_lowputc, . - up_lowputc
/* This performs basic initialization of the UART. This can be called very
* early in initialization because it does not depend on having a stack. It
* modifies r0-r2 and r14.
*/
.text
.globl up_lowsetup
.type up_lowsetup, function
up_lowsetup:
/* Configure PINSEL0 */
ldr r0, =PINSELECT /* TODO: generalize this for different uart pins */
ldr r1, [r0]
ldr r2, =(~UARTxPINMASK)
and r1, r2
ldr r2, =(UARTxPINSEL)
orr r1, r2
str r1, [r0]
/* Power Up Uart0 */
ldr r0, =UARTxPCLKSEL /* PCLKSEL0 address */
ldr r1, [r0]
ldr r2, =(~PCLKSEL_MASK)
and r1, r2
ldr r2, =(U0_PCLKSEL)
orr r1, r2
str r1, [r0]
/* Configure parity, data bits, stop bits and set DLAB=1 */
ldr r0, =UARTxBASE
mov r1, #(LCR_VALUE | LCR_DLAB_ENABLE)
strb r1, [r0, #UART_LCR_OFFSET]
/* Set the BAUD divisor */
mov r1, #((MULVAL << 4) | DIVADDVAL)
strb r1, [r0, #UART_FDR_OFFSET]
mov r1, #DLMVAL
strb r1, [r0, #UART_DLM_OFFSET]
mov r1, #DLLVAL
strb r1, [r0, #UART_DLL_OFFSET]
/* Clear DLAB and Set format 8N1 */
mov r1, #LCR_VALUE
strb r1, [r0, #UART_LCR_OFFSET]
/* Configure the FIFOs */
mov r1, #FCR_VALUE
strb r1, [r0, #UART_FCR_OFFSET]
mov r1, #LCR_VALUE
strb r1, [r0, #UART_LCR_OFFSET]
/* And return */
mov pc, lr
.size up_lowsetup, . - up_lowsetup
.end
|
