1 /* 2 * (C) Copyright 2004-2007 Freescale Semiconductor, Inc. 3 * TsiChung Liew, Tsi-Chung.Liew@freescale.com. 4 * 5 * See file CREDITS for list of people who contributed to this 6 * project. 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License as 10 * published by the Free Software Foundation; either version 2 of 11 * the License, or (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21 * MA 02111-1307 USA 22 * 23 */ 24 25 /* 26 * Minimal serial functions needed to use one of the uart ports 27 * as serial console interface. 28 */ 29 30 #include <common.h> 31 #include <asm/immap.h> 32 #include <asm/uart.h> 33 34 DECLARE_GLOBAL_DATA_PTR; 35 36 #ifdef CONFIG_MCFSERIAL 37 int serial_init(void) 38 { 39 volatile uart_t *uart; 40 u32 counter; 41 42 uart = (volatile uart_t *)(CFG_UART_BASE); 43 44 /* write to SICR: SIM2 = uart mode,dcd does not affect rx */ 45 uart->ucr = UART_UCR_RESET_RX; 46 uart->ucr = UART_UCR_RESET_TX; 47 uart->ucr = UART_UCR_RESET_ERROR; 48 uart->ucr = UART_UCR_RESET_MR; 49 __asm__("nop"); 50 51 uart->uimr = 0; 52 53 /* write to CSR: RX/TX baud rate from timers */ 54 uart->ucsr = (UART_UCSR_RCS_SYS_CLK | UART_UCSR_TCS_SYS_CLK); 55 56 uart->umr = (UART_UMR_BC_8 | UART_UMR_PM_NONE); 57 uart->umr = UART_UMR_SB_STOP_BITS_1; 58 59 /* Setting up BaudRate */ 60 counter = (u32) (gd->bus_clk / (gd->baudrate)); 61 counter >>= 5; 62 63 /* write to CTUR: divide counter upper byte */ 64 uart->ubg1 = (u8) ((counter & 0xff00) >> 8); 65 /* write to CTLR: divide counter lower byte */ 66 uart->ubg2 = (u8) (counter & 0x00ff); 67 68 uart->ucr = (UART_UCR_RX_ENABLED | UART_UCR_TX_ENABLED); 69 70 return (0); 71 } 72 73 void serial_putc(const char c) 74 { 75 volatile uart_t *uart = (volatile uart_t *)(CFG_UART_BASE); 76 77 if (c == '\n') 78 serial_putc('\r'); 79 80 /* Wait for last character to go. */ 81 while (!(uart->usr & UART_USR_TXRDY)) ; 82 83 uart->utb = c; 84 } 85 86 void serial_puts(const char *s) 87 { 88 while (*s) { 89 serial_putc(*s++); 90 } 91 } 92 93 int serial_getc(void) 94 { 95 volatile uart_t *uart = (volatile uart_t *)(CFG_UART_BASE); 96 97 /* Wait for a character to arrive. */ 98 while (!(uart->usr & UART_USR_RXRDY)) ; 99 return uart->urb; 100 } 101 102 int serial_tstc(void) 103 { 104 volatile uart_t *uart = (volatile uart_t *)(CFG_UART_BASE); 105 106 return (uart->usr & UART_USR_RXRDY); 107 } 108 109 void serial_setbrg(void) 110 { 111 volatile uart_t *uart = (volatile uart_t *)(CFG_UART_BASE); 112 u32 counter; 113 114 counter = ((gd->bus_clk / gd->baudrate)) >> 5; 115 counter++; 116 117 /* write to CTUR: divide counter upper byte */ 118 uart->ubg1 = ((counter & 0xff00) >> 8); 119 /* write to CTLR: divide counter lower byte */ 120 uart->ubg2 = (counter & 0x00ff); 121 122 uart->ucr = UART_UCR_RESET_RX; 123 uart->ucr = UART_UCR_RESET_TX; 124 125 uart->ucr = UART_UCR_RX_ENABLED | UART_UCR_TX_ENABLED; 126 } 127 #endif /* CONFIG_MCFSERIAL */ 128