1/* 2 * COM1 NS16550 support 3 */ 4 5#include <linux/types.h> 6#include <linux/serial.h> 7#include <linux/serial_reg.h> 8#include <asm/serial.h> 9 10#if defined(CONFIG_XILINX_VIRTEX) 11#include <platforms/4xx/xparameters/xparameters.h> 12#endif 13#include "nonstdio.h" 14#include "serial.h" 15 16#define SERIAL_BAUD 9600 17 18extern unsigned long ISA_io; 19 20static struct serial_state rs_table[RS_TABLE_SIZE] = { 21 SERIAL_PORT_DFNS /* Defined in <asm/serial.h> */ 22}; 23 24static int shift; 25 26unsigned long serial_init(int chan, void *ignored) 27{ 28 unsigned long com_port, base_baud; 29 unsigned char lcr, dlm; 30 31 /* We need to find out which type io we're expecting. If it's 32 * 'SERIAL_IO_PORT', we get an offset from the isa_io_base. 33 * If it's 'SERIAL_IO_MEM', we can the exact location. -- Tom */ 34 switch (rs_table[chan].io_type) { 35 case SERIAL_IO_PORT: 36 com_port = rs_table[chan].port; 37 break; 38 case SERIAL_IO_MEM: 39 com_port = (unsigned long)rs_table[chan].iomem_base; 40 break; 41 default: 42 /* We can't deal with it. */ 43 return -1; 44 } 45 46 /* How far apart the registers are. */ 47 shift = rs_table[chan].iomem_reg_shift; 48 /* Base baud.. */ 49 base_baud = rs_table[chan].baud_base; 50 51 /* save the LCR */ 52 lcr = inb(com_port + (UART_LCR << shift)); 53 /* Access baud rate */ 54 outb(com_port + (UART_LCR << shift), 0x80); 55 dlm = inb(com_port + (UART_DLM << shift)); 56 /* 57 * Test if serial port is unconfigured. 58 * We assume that no-one uses less than 110 baud or 59 * less than 7 bits per character these days. 60 * -- paulus. 61 */ 62 63 if ((dlm <= 4) && (lcr & 2)) 64 /* port is configured, put the old LCR back */ 65 outb(com_port + (UART_LCR << shift), lcr); 66 else { 67 /* Input clock. */ 68 outb(com_port + (UART_DLL << shift), 69 (base_baud / SERIAL_BAUD) & 0xFF); 70 outb(com_port + (UART_DLM << shift), 71 (base_baud / SERIAL_BAUD) >> 8); 72 /* 8 data, 1 stop, no parity */ 73 outb(com_port + (UART_LCR << shift), 0x03); 74 /* RTS/DTR */ 75 outb(com_port + (UART_MCR << shift), 0x03); 76 } 77 /* Clear & enable FIFOs */ 78 outb(com_port + (UART_FCR << shift), 0x07); 79 80 return (com_port); 81} 82 83void 84serial_putc(unsigned long com_port, unsigned char c) 85{ 86 while ((inb(com_port + (UART_LSR << shift)) & UART_LSR_THRE) == 0) 87 ; 88 outb(com_port, c); 89} 90 91unsigned char 92serial_getc(unsigned long com_port) 93{ 94 while ((inb(com_port + (UART_LSR << shift)) & UART_LSR_DR) == 0) 95 ; 96 return inb(com_port); 97} 98 99int 100serial_tstc(unsigned long com_port) 101{ 102 return ((inb(com_port + (UART_LSR << shift)) & UART_LSR_DR) != 0); 103} 104