/* * Copyright (C) 2015 Freescale Semiconductor, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include #include /* uart register defines */ #define UART_RBR 0x0 #define UART_THR 0x0 #define UART_IER 0x1 #define UART_FCR 0x2 #define UART_LCR 0x3 #define UART_MCR 0x4 #define UART_LSR 0x5 #define UART_MSR 0x6 #define UART_SPR 0x7 /* uart status register bits */ #define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */ void ns16550_flush(vaddr_t base) { while ((read8(base + UART_LSR) & UART_LSR_THRE) == 0) ; } void ns16550_putc(int ch, vaddr_t base) { ns16550_flush(base); /* write out charset to Transmit-hold-register */ write8(ch, base + UART_THR); }