1 /* 2 * Copyright (c) 2017, Linaro Limited 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright notice, 12 * this list of conditions and the following disclaimer in the documentation 13 * and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 19 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25 * POSSIBILITY OF SUCH DAMAGE. 26 */ 27 #include <drivers/stih_asc.h> 28 #include <io.h> 29 #include <util.h> 30 31 #define ASC_BAUDRATE 0x00 32 #define ASC_TXBUFFER 0x04 33 #define ASC_STATUS 0x14 34 35 #define ASC_STATUS_TX_EMPTY BIT(1) 36 #define ASC_STATUS_TX_HALF_EMPTY BIT(2) 37 38 void stih_asc_flush(vaddr_t base) 39 { 40 while (!(read32(base + ASC_STATUS) & ASC_STATUS_TX_EMPTY)) 41 ; 42 } 43 44 void stih_asc_putc(int ch, vaddr_t base) 45 { 46 /* Wait until there is space in the FIFO */ 47 while (!(read32(base + ASC_STATUS) & ASC_STATUS_TX_HALF_EMPTY)) 48 ; 49 50 /* Send the character */ 51 write32(ch, base + ASC_TXBUFFER); 52 } 53 54 void stih_asc_init(vaddr_t base) 55 { 56 /* 57 * Console setup relies on early bootstage or nonsecure world. 58 * Only flush ASC FIFO if possible. 59 */ 60 console_flush(); 61 } 62