2 * (c) 2004 Sascha Hauer <sascha@saschahauer.de>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include <asm/arch/imx-regs.h>
23 #include <linux/compiler.h>
25 #if defined CONFIG_IMX_SERIAL1
26 #define UART_BASE IMX_UART1_BASE
27 #elif defined CONFIG_IMX_SERIAL2
28 #define UART_BASE IMX_UART2_BASE
30 #error "define CONFIG_IMX_SERIAL1, CONFIG_IMX_SERIAL2 or CONFIG_IMX_SERIAL_NONE"
34 volatile uint32_t urxd
[16];
35 volatile uint32_t utxd
[16];
36 volatile uint32_t ucr1
;
37 volatile uint32_t ucr2
;
38 volatile uint32_t ucr3
;
39 volatile uint32_t ucr4
;
40 volatile uint32_t ufcr
;
41 volatile uint32_t usr1
;
42 volatile uint32_t usr2
;
43 volatile uint32_t uesc
;
44 volatile uint32_t utim
;
45 volatile uint32_t ubir
;
46 volatile uint32_t ubmr
;
47 volatile uint32_t ubrc
;
48 volatile uint32_t bipr
[4];
49 volatile uint32_t bmpr
[4];
50 volatile uint32_t uts
;
53 DECLARE_GLOBAL_DATA_PTR
;
55 static void imx_serial_setbrg(void)
60 extern void imx_gpio_mode(int gpio_mode
);
63 * Initialise the serial port with the given baudrate. The settings
64 * are always 8 data bits, no parity, 1 stop bit, no start bits.
67 static int imx_serial_init(void)
69 volatile struct imx_serial
* base
= (struct imx_serial
*)UART_BASE
;
70 unsigned int ufcr_rfdiv
;
73 #ifdef CONFIG_IMX_SERIAL1
74 imx_gpio_mode(PC11_PF_UART1_TXD
);
75 imx_gpio_mode(PC12_PF_UART1_RXD
);
77 imx_gpio_mode(PB30_PF_UART2_TXD
);
78 imx_gpio_mode(PB31_PF_UART2_RXD
);
82 base
->ucr1
&= ~UCR1_UARTEN
;
84 /* Set to default POR state */
86 base
->ucr1
= 0x00000004;
87 base
->ucr2
= 0x00000000;
88 base
->ucr3
= 0x00000000;
89 base
->ucr4
= 0x00008040;
90 base
->uesc
= 0x0000002B;
91 base
->utim
= 0x00000000;
92 base
->ubir
= 0x00000000;
93 base
->ubmr
= 0x00000000;
94 base
->uts
= 0x00000000;
96 base
->ucr4
|= UCR4_REF16
;
101 /* set the baud rate.
110 * each register is 16 bits wide. refclk max is 96 MHz
114 ufcr_rfdiv
= ((base
->ufcr
) & UFCR_RFDIV
) >> 7;
118 ufcr_rfdiv
= 6 - ufcr_rfdiv
;
120 refclk
= get_PERCLK1();
121 refclk
/= ufcr_rfdiv
;
123 /* Set the numerator value minus one of the BRM ratio */
124 base
->ubir
= (gd
->baudrate
/ 100) - 1;
126 /* Set the denominator value minus one of the BRM ratio */
127 base
->ubmr
= (refclk
/(16 * 100)) - 1;
130 base
->ucr2
&= ~UCR2_PREN
;
131 base
->ucr2
|= UCR2_WS
;
132 base
->ucr2
&= ~UCR2_STPB
;
135 base
->ucr2
|= UCR2_IRTS
;
138 base
->ucr1
|= UCR1_UARTEN
| UCR1_UARTCLKEN
;
141 base
->ucr2
|= UCR2_SRST
| UCR2_RXEN
| UCR2_TXEN
;
143 /* Clear status flags */
144 base
->usr2
|= USR2_ADET
|
153 /* Clear status flags */
154 base
->usr1
|= USR1_PARITYERR
|
164 * Read a single byte from the serial port. Returns 1 on success, 0
165 * otherwise. When the function is successful, the character read is
166 * written into its argument c.
168 static int imx_serial_getc(void)
170 volatile struct imx_serial
* base
= (struct imx_serial
*)UART_BASE
;
173 while(base
->uts
& UTS_RXEMPTY
);
175 ch
= (char)base
->urxd
[0];
181 static int hwflow
= 0; /* turned off by default */
182 int hwflow_onoff(int on
)
188 * Output a single byte to the serial port.
190 static void imx_serial_putc(const char c
)
192 volatile struct imx_serial
* base
= (struct imx_serial
*)UART_BASE
;
194 /* Wait for Tx FIFO not full */
195 while (base
->uts
& UTS_TXFULL
);
199 /* If \n, also do \r */
205 * Test whether a character is in the RX buffer
207 static int imx_serial_tstc(void)
209 volatile struct imx_serial
* base
= (struct imx_serial
*)UART_BASE
;
211 /* If receive fifo is empty, return false */
212 if (base
->uts
& UTS_RXEMPTY
)
217 static struct serial_device imx_serial_drv
= {
218 .name
= "imx_serial",
219 .start
= imx_serial_init
,
221 .setbrg
= imx_serial_setbrg
,
222 .putc
= imx_serial_putc
,
223 .puts
= default_serial_puts
,
224 .getc
= imx_serial_getc
,
225 .tstc
= imx_serial_tstc
,
228 void imx_serial_initialize(void)
230 serial_register(&imx_serial_drv
);
233 __weak
struct serial_device
*default_serial_console(void)
235 return &imx_serial_drv
;