1 #include <part/fallback_boot.h>
4 #ifndef CONFIG_TTYS0_BASE
5 #define CONFIG_TTYS0_BASE 0x3f8
8 #ifndef CONFIG_TTYS0_BAUD
9 #define CONFIG_TTYS0_BAUD 115200
12 #if ((115200%CONFIG_TTYS0_BAUD) != 0)
13 #error Bad ttys0 baud rate
16 #ifndef CONFIG_TTYS0_DIV
17 #define CONFIG_TTYS0_DIV (115200/CONFIG_TTYS0_BAUD)
20 /* Line Control Settings */
21 #ifndef CONFIG_TTYS0_LCS
22 /* Set 8bit, 1 stop bit, no parity */
23 #define CONFIG_TTYS0_LCS 0x3
26 #define UART_LCS CONFIG_TTYS0_LCS
29 #if CONFIG_USE_PRINTK_IN_CAR == 0
49 static int uart_can_tx_byte(void)
51 return inb(CONFIG_TTYS0_BASE + UART_LSR) & 0x20;
54 static void uart_wait_to_tx_byte(void)
56 while(!uart_can_tx_byte())
60 static void uart_wait_until_sent(void)
62 while(!(inb(CONFIG_TTYS0_BASE + UART_LSR) & 0x40))
66 static void uart_tx_byte(unsigned char data)
68 uart_wait_to_tx_byte();
69 outb(data, CONFIG_TTYS0_BASE + UART_TBR);
70 /* Make certain the data clears the fifos */
71 uart_wait_until_sent();
76 /* disable interrupts */
77 outb(0x0, CONFIG_TTYS0_BASE + UART_IER);
79 outb(0x01, CONFIG_TTYS0_BASE + UART_FCR);
80 /* Set Baud Rate Divisor to 12 ==> 115200 Baud */
81 outb(0x80 | UART_LCS, CONFIG_TTYS0_BASE + UART_LCR);
82 #if CONFIG_USE_OPTION_TABLE == 1
83 static const unsigned char divisor[] = { 1,2,3,6,12,24,48,96 };
84 unsigned ttys0_div, ttys0_index;
85 ttys0_index = read_option(CMOS_VSTART_baud_rate, CMOS_VLEN_baud_rate, 0);
87 ttys0_div = divisor[ttys0_index];
88 outb(ttys0_div & 0xff, CONFIG_TTYS0_BASE + UART_DLL);
89 outb(0, CONFIG_TTYS0_BASE + UART_DLM);
91 outb(CONFIG_TTYS0_DIV & 0xFF, CONFIG_TTYS0_BASE + UART_DLL);
92 outb((CONFIG_TTYS0_DIV >> 8) & 0xFF, CONFIG_TTYS0_BASE + UART_DLM);
94 outb(UART_LCS, CONFIG_TTYS0_BASE + UART_LCR);
98 /* CONFIG_USE_PRINTK_IN_CAR == 1 */
100 extern void uart8250_init(unsigned base_port, unsigned divisor, unsigned lcs);
103 #if CONFIG_USE_OPTION_TABLE == 1
104 static const unsigned char divisor[] = { 1,2,3,6,12,24,48,96 };
105 unsigned ttys0_div, ttys0_index;
106 ttys0_index = read_option(CMOS_VSTART_baud_rate, CMOS_VLEN_baud_rate, 0);
108 ttys0_div = divisor[ttys0_index];
109 uart8250_init(CONFIG_TTYS0_BASE, ttys0_div, UART_LCS);
111 uart8250_init(CONFIG_TTYS0_BASE, CONFIG_TTYS0_DIV, UART_LCS);