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 <keep.h> 30 #include <util.h> 31 32 #define ASC_BAUDRATE 0x00 33 #define ASC_TXBUFFER 0x04 34 #define ASC_STATUS 0x14 35 36 #define ASC_STATUS_TX_EMPTY BIT(1) 37 #define ASC_STATUS_TX_HALF_EMPTY BIT(2) 38 39 static vaddr_t chip_to_base(struct serial_chip *chip) 40 { 41 struct stih_asc_pd *pd = 42 container_of(chip, struct stih_asc_pd, chip); 43 44 return io_pa_or_va(&pd->base); 45 } 46 47 static void stih_asc_flush(struct serial_chip *chip) 48 { 49 vaddr_t base = chip_to_base(chip); 50 51 while (!(read32(base + ASC_STATUS) & ASC_STATUS_TX_EMPTY)) 52 ; 53 } 54 55 static void stih_asc_putc(struct serial_chip *chip, int ch) 56 { 57 vaddr_t base = chip_to_base(chip); 58 59 while (!(read32(base + ASC_STATUS) & ASC_STATUS_TX_HALF_EMPTY)) 60 ; 61 62 write32(ch, base + ASC_TXBUFFER); 63 } 64 65 static const struct serial_ops stih_asc_ops = { 66 .flush = stih_asc_flush, 67 .putc = stih_asc_putc, 68 }; 69 KEEP_PAGER(stih_asc_ops); 70 71 void stih_asc_init(struct stih_asc_pd *pd, vaddr_t base) 72 { 73 pd->base.pa = base; 74 pd->chip.ops = &stih_asc_ops; 75 } 76