1 /* GRLIB APBUART Serial controller driver
4 * Daniel Hellstrom, Gaisler Research, daniel@gaisler.com.
6 * See file CREDITS for list of people who contributed to this
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of
12 * the License, or (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 #include <asm/processor.h>
30 #include <linux/compiler.h>
32 DECLARE_GLOBAL_DATA_PTR;
34 static int leon2_serial_init(void)
36 LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
37 LEON2_Uart_regs *regs;
42 * Set scaler / baud rate
44 * Receiver & transmitter enable
46 #if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
47 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
49 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
52 regs->UART_Scaler = CONFIG_SYS_LEON2_UART1_SCALER;
54 /* Let bit 11 be unchanged (debug bit for GRMON) */
55 tmp = READ_WORD(regs->UART_Control);
57 regs->UART_Control = ((tmp & LEON2_UART_CTRL_DBG) |
58 (LEON2_UART1_LOOPBACK_ENABLE << 7) |
59 (LEON2_UART1_FLOWCTRL_ENABLE << 6) |
60 (LEON2_UART1_PARITY_ENABLE << 5) |
61 (LEON2_UART1_ODDPAR_ENABLE << 4) |
62 LEON2_UART_CTRL_RE | LEON2_UART_CTRL_TE);
67 static void leon2_serial_putc_raw(const char c)
69 LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
70 LEON2_Uart_regs *regs;
72 #if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
73 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
75 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
78 /* Wait for last character to go. */
79 while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_THE)) ;
82 regs->UART_Channel = c;
85 /* Wait for data to be sent */
86 while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_TSE)) ;
90 static void leon2_serial_putc(const char c)
93 leon2_serial_putc_raw('\r');
95 leon2_serial_putc_raw(c);
98 static int leon2_serial_getc(void)
100 LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
101 LEON2_Uart_regs *regs;
103 #if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
104 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
106 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
109 /* Wait for a character to arrive. */
110 while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_DR)) ;
113 return READ_WORD(regs->UART_Channel);
116 static int leon2_serial_tstc(void)
118 LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
119 LEON2_Uart_regs *regs;
121 #if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
122 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
124 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
127 return (READ_WORD(regs->UART_Status) & LEON2_UART_STAT_DR);
130 /* set baud rate for uart */
131 static void leon2_serial_setbrg(void)
133 /* update baud rate settings, read it from gd->baudrate */
135 LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
136 LEON2_Uart_regs *regs;
138 #if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
139 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
141 regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
144 if (gd->baudrate > 0) {
146 (((CONFIG_SYS_CLK_FREQ * 10) / (gd->baudrate * 8)) -
148 regs->UART_Scaler = scaler;
152 static struct serial_device leon2_serial_drv = {
153 .name = "leon2_serial",
154 .start = leon2_serial_init,
156 .setbrg = leon2_serial_setbrg,
157 .putc = leon2_serial_putc,
158 .puts = default_serial_puts,
159 .getc = leon2_serial_getc,
160 .tstc = leon2_serial_tstc,
163 void leon2_serial_initialize(void)
165 serial_register(&leon2_serial_drv);
168 __weak struct serial_device *default_serial_console(void)
170 return &leon2_serial_drv;