1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2017, Linaro Limited 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * 12 * 2. Redistributions in binary form must reproduce the above copyright notice, 13 * this list of conditions and the following disclaimer in the documentation 14 * and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 #include <drivers/stih_asc.h> 29 #include <io.h> 30 #include <keep.h> 31 #include <util.h> 32 33 #define ASC_BAUDRATE 0x00 34 #define ASC_TXBUFFER 0x04 35 #define ASC_STATUS 0x14 36 37 #define ASC_STATUS_TX_EMPTY BIT(1) 38 #define ASC_STATUS_TX_HALF_EMPTY BIT(2) 39 40 static vaddr_t chip_to_base(struct serial_chip *chip) 41 { 42 struct stih_asc_pd *pd = 43 container_of(chip, struct stih_asc_pd, chip); 44 45 return io_pa_or_va(&pd->base); 46 } 47 48 static void stih_asc_flush(struct serial_chip *chip) 49 { 50 vaddr_t base = chip_to_base(chip); 51 52 while (!(read32(base + ASC_STATUS) & ASC_STATUS_TX_EMPTY)) 53 ; 54 } 55 56 static void stih_asc_putc(struct serial_chip *chip, int ch) 57 { 58 vaddr_t base = chip_to_base(chip); 59 60 while (!(read32(base + ASC_STATUS) & ASC_STATUS_TX_HALF_EMPTY)) 61 ; 62 63 write32(ch, base + ASC_TXBUFFER); 64 } 65 66 static const struct serial_ops stih_asc_ops = { 67 .flush = stih_asc_flush, 68 .putc = stih_asc_putc, 69 }; 70 KEEP_PAGER(stih_asc_ops); 71 72 void stih_asc_init(struct stih_asc_pd *pd, vaddr_t base) 73 { 74 pd->base.pa = base; 75 pd->chip.ops = &stih_asc_ops; 76 } 77