From 1e3827d9cf9442e188604fd1099ac38375135125 Mon Sep 17 00:00:00 2001 From: Peter Tyser Date: Mon, 12 Apr 2010 22:28:14 -0500 Subject: mips: Move cpu/mips/* to arch/mips/cpu/* Signed-off-by: Peter Tyser --- arch/mips/cpu/au1x00_serial.c | 131 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 131 insertions(+) create mode 100644 arch/mips/cpu/au1x00_serial.c (limited to 'arch/mips/cpu/au1x00_serial.c') diff --git a/arch/mips/cpu/au1x00_serial.c b/arch/mips/cpu/au1x00_serial.c new file mode 100644 index 0000000000..c25ba5a5b3 --- /dev/null +++ b/arch/mips/cpu/au1x00_serial.c @@ -0,0 +1,131 @@ +/* + * AU1X00 UART support + * + * Hardcoded to UART 0 for now + * Speed and options also hardcoded to 115200 8N1 + * + * Copyright (c) 2003 Thomas.Lange@corelatus.se + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include +#include +#include + +/****************************************************************************** +* +* serial_init - initialize a channel +* +* This routine initializes the number of data bits, parity +* and set the selected baud rate. Interrupts are disabled. +* Set the modem control signals if the option is selected. +* +* RETURNS: N/A +*/ + +int serial_init (void) +{ + volatile u32 *uart_fifoctl = (volatile u32*)(UART0_ADDR+UART_FCR); + volatile u32 *uart_enable = (volatile u32*)(UART0_ADDR+UART_ENABLE); + + /* Enable clocks first */ + *uart_enable = UART_EN_CE; + + /* Then release reset */ + /* Must release reset before setting other regs */ + *uart_enable = UART_EN_CE|UART_EN_E; + + /* Activate fifos, reset tx and rx */ + /* Set tx trigger level to 12 */ + *uart_fifoctl = UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR| + UART_FCR_CLEAR_XMIT|UART_FCR_T_TRIGGER_12; + + serial_setbrg(); + + return 0; +} + + +void serial_setbrg (void) +{ + volatile u32 *uart_clk = (volatile u32*)(UART0_ADDR+UART_CLK); + volatile u32 *uart_lcr = (volatile u32*)(UART0_ADDR+UART_LCR); + volatile u32 *sys_powerctrl = (u32 *)SYS_POWERCTRL; + int sd; + int divisorx2; + + /* sd is system clock divisor */ + /* see section 10.4.5 in au1550 datasheet */ + sd = (*sys_powerctrl & 0x03) + 2; + + /* calulate 2x baudrate and round */ + divisorx2 = ((CONFIG_SYS_MIPS_TIMER_FREQ/(sd * 16 * CONFIG_BAUDRATE))); + + if (divisorx2 & 0x01) + divisorx2 = divisorx2 + 1; + + *uart_clk = divisorx2 / 2; + + /* Set parity, stop bits and word length to 8N1 */ + *uart_lcr = UART_LCR_WLEN8; +} + +void serial_putc (const char c) +{ + volatile u32 *uart_lsr = (volatile u32*)(UART0_ADDR+UART_LSR); + volatile u32 *uart_tx = (volatile u32*)(UART0_ADDR+UART_TX); + + if (c == '\n') serial_putc ('\r'); + + /* Wait for fifo to shift out some bytes */ + while((*uart_lsr&UART_LSR_THRE)==0); + + *uart_tx = (u32)c; +} + +void serial_puts (const char *s) +{ + while (*s) + { + serial_putc (*s++); + } +} + +int serial_getc (void) +{ + volatile u32 *uart_rx = (volatile u32*)(UART0_ADDR+UART_RX); + char c; + + while (!serial_tstc()); + + c = (*uart_rx&0xFF); + return c; +} + +int serial_tstc (void) +{ + volatile u32 *uart_lsr = (volatile u32*)(UART0_ADDR+UART_LSR); + + if(*uart_lsr&UART_LSR_DR){ + /* Data in rfifo */ + return(1); + } + return 0; +} -- cgit v1.2.1