/* * (C) Copyright 2000 * Rob Taylor, Flying Pig Systems. robt@flyingpig.com. * * (C) Copyright 2004 * ARM Ltd. * Philippe Robin, <philippe.robin@arm.com> * * 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 */ /* Simple U-Boot driver for the PrimeCell PL011 UARTs on the IntegratorCP */ /* Should be fairly simple to make it work with the PL010 as well */ #include <common.h> #ifdef CFG_PL011_SERIAL #include "serial_pl011.h" #define IO_WRITE(addr, val) (*(volatile unsigned int *)(addr) = (val)) #define IO_READ(addr) (*(volatile unsigned int *)(addr)) /* * IntegratorCP has two UARTs, use the first one, at 38400-8-N-1 * Versatile PB has four UARTs. */ #define CONSOLE_PORT CONFIG_CONS_INDEX #define baudRate CONFIG_BAUDRATE static volatile unsigned char *const port[] = CONFIG_PL01x_PORTS; #define NUM_PORTS (sizeof(port)/sizeof(port[0])) static void pl011_putc (int portnum, char c); static int pl011_getc (int portnum); static int pl011_tstc (int portnum); int serial_init (void) { unsigned int temp; unsigned int divider; unsigned int remainder; unsigned int fraction; /* ** First, disable everything. */ IO_WRITE (port[CONSOLE_PORT] + UART_PL011_CR, 0x0); /* ** Set baud rate ** ** IBRD = UART_CLK / (16 * BAUD_RATE) ** FBRD = ROUND((64 * MOD(UART_CLK,(16 * BAUD_RATE))) / (16 * BAUD_RATE)) */ temp = 16 * baudRate; divider = CONFIG_PL011_CLOCK / temp; remainder = CONFIG_PL011_CLOCK % temp; temp = (8 * remainder) / baudRate; fraction = (temp >> 1) + (temp & 1); IO_WRITE (port[CONSOLE_PORT] + UART_PL011_IBRD, divider); IO_WRITE (port[CONSOLE_PORT] + UART_PL011_FBRD, fraction); /* ** Set the UART to be 8 bits, 1 stop bit, no parity, fifo enabled. */ IO_WRITE (port[CONSOLE_PORT] + UART_PL011_LCRH, (UART_PL011_LCRH_WLEN_8 | UART_PL011_LCRH_FEN)); /* ** Finally, enable the UART */ IO_WRITE (port[CONSOLE_PORT] + UART_PL011_CR, (UART_PL011_CR_UARTEN | UART_PL011_CR_TXE | UART_PL011_CR_RXE)); return 0; } void serial_putc (const char c) { if (c == '\n') pl011_putc (CONSOLE_PORT, '\r'); pl011_putc (CONSOLE_PORT, c); } void serial_puts (const char *s) { while (*s) { serial_putc (*s++); } } int serial_getc (void) { return pl011_getc (CONSOLE_PORT); } int serial_tstc (void) { return pl011_tstc (CONSOLE_PORT); } void serial_setbrg (void) { } static void pl011_putc (int portnum, char c) { /* Wait until there is space in the FIFO */ while (IO_READ (port[portnum] + UART_PL01x_FR) & UART_PL01x_FR_TXFF); /* Send the character */ IO_WRITE (port[portnum] + UART_PL01x_DR, c); } static int pl011_getc (int portnum) { unsigned int data; /* Wait until there is data in the FIFO */ while (IO_READ (port[portnum] + UART_PL01x_FR) & UART_PL01x_FR_RXFE); data = IO_READ (port[portnum] + UART_PL01x_DR); /* Check for an error flag */ if (data & 0xFFFFFF00) { /* Clear the error */ IO_WRITE (port[portnum] + UART_PL01x_ECR, 0xFFFFFFFF); return -1; } return (int) data; } static int pl011_tstc (int portnum) { return !(IO_READ (port[portnum] + UART_PL01x_FR) & UART_PL01x_FR_RXFE); } #endif