| void outb(unsigned char value, unsigned short port) |
| { |
| __builtin_outb(value, port); |
| } |
| |
| unsigned char inb(unsigned short port) |
| { |
| return __builtin_inb(port); |
| } |
| |
| /* Base Address */ |
| #ifndef CONFIG_TTYS0_BASE |
| #define CONFIG_TTYS0_BASE 0x3f8 |
| #endif |
| |
| #ifndef CONFIG_TTYS0_BAUD |
| #define CONFIG_TTYS0_BAUD 115200 |
| #endif |
| |
| #if ((115200%CONFIG_TTYS0_BAUD) != 0) |
| #error Bad ttys0 baud rate |
| #endif |
| |
| #if CONFIG_TTYS0_BAUD == 115200 |
| #define CONFIG_TTYS0_DIV (1) |
| #else |
| #define CONFIG_TTYS0_DIV (115200/CONFIG_TTYS0_BAUD) |
| #endif |
| |
| /* Line Control Settings */ |
| #ifndef CONFIG_TTYS0_LCS |
| /* Set 8bit, 1 stop bit, no parity */ |
| #define CONFIG_TTYS0_LCS 0x3 |
| #endif |
| |
| #define UART_LCS CONFIG_TTYS0_LCS |
| |
| /* Data */ |
| #define UART_RBR 0x00 |
| #define UART_TBR 0x00 |
| |
| /* Control */ |
| #define UART_IER 0x01 |
| #define UART_IIR 0x02 |
| #define UART_FCR 0x02 |
| #define UART_LCR 0x03 |
| #define UART_MCR 0x04 |
| #define UART_DLL 0x00 |
| #define UART_DLM 0x01 |
| |
| /* Status */ |
| #define UART_LSR 0x05 |
| #define UART_MSR 0x06 |
| #define UART_SCR 0x07 |
| |
| int uart_can_tx_byte(void) |
| { |
| return inb(CONFIG_TTYS0_BASE + UART_LSR) & 0x20; |
| } |
| |
| void uart_wait_to_tx_byte(void) |
| { |
| while(!uart_can_tx_byte()) |
| ; |
| } |
| |
| void uart_wait_until_sent(void) |
| { |
| while(!(inb(CONFIG_TTYS0_BASE + UART_LSR) & 0x40)) |
| ; |
| } |
| |
| static void uart_tx_byte(unsigned char data) |
| { |
| uart_wait_to_tx_byte(); |
| outb(data, CONFIG_TTYS0_BASE + UART_TBR); |
| /* Make certain the data clears the fifos */ |
| uart_wait_until_sent(); |
| } |
| |
| |
| void uart_init(void) |
| { |
| /* disable interrupts */ |
| outb(0x0, CONFIG_TTYS0_BASE + UART_IER); |
| /* enable fifo's */ |
| outb(0x01, CONFIG_TTYS0_BASE + UART_FCR); |
| /* Set Baud Rate Divisor to 12 ==> 115200 Baud */ |
| outb(0x80 | UART_LCS, CONFIG_TTYS0_BASE + UART_LCR); |
| outb(CONFIG_TTYS0_DIV & 0xFF, CONFIG_TTYS0_BASE + UART_DLL); |
| outb((CONFIG_TTYS0_DIV >> 8) & 0xFF, CONFIG_TTYS0_BASE + UART_DLM); |
| outb(UART_LCS, CONFIG_TTYS0_BASE + UART_LCR); |
| } |
| |
| |
| void __console_tx_char(unsigned char byte) |
| { |
| uart_tx_byte(byte); |
| |
| } |
| |
| void __console_tx_string(char *str) |
| { |
| unsigned char ch; |
| while((ch = *str++) != '\0') { |
| __console_tx_char(ch); |
| } |
| } |
| |
| |
| void print_debug_char(unsigned char byte) { __console_tx_char(byte); } |
| void print_debug(char *str) { __console_tx_string(str); } |
| |
| void main(void) |
| { |
| static const char msg[] = "hello world\r\n"; |
| uart_init(); |
| #if 0 |
| print_debug(msg); |
| #endif |
| #if 1 |
| print_debug("hello world\r\n"); |
| print_debug("how are you today\r\n"); |
| #endif |
| while(1) { |
| ; |
| } |
| } |