| // SPDX-License-Identifier: BSD-2-Clause |
| /* |
| * Copyright (C) 2015 Freescale Semiconductor, Inc. |
| * Copyright (c) 2017, Linaro Limited |
| * 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 <drivers/ns16550.h> |
| #include <io.h> |
| #include <keep.h> |
| #include <util.h> |
| |
| /* 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 */ |
| |
| static vaddr_t chip_to_base(struct serial_chip *chip) |
| { |
| struct ns16550_data *pd = |
| container_of(chip, struct ns16550_data, chip); |
| |
| return io_pa_or_va(&pd->base); |
| } |
| |
| static void ns16550_flush(struct serial_chip *chip) |
| { |
| vaddr_t base = chip_to_base(chip); |
| |
| while ((io_read8(base + UART_LSR) & UART_LSR_THRE) == 0) |
| ; |
| } |
| |
| static void ns16550_putc(struct serial_chip *chip, int ch) |
| { |
| vaddr_t base = chip_to_base(chip); |
| |
| ns16550_flush(chip); |
| |
| /* write out charset to Transmit-hold-register */ |
| io_write8(base + UART_THR, ch); |
| } |
| |
| static const struct serial_ops ns16550_ops = { |
| .flush = ns16550_flush, |
| .putc = ns16550_putc, |
| }; |
| KEEP_PAGER(ns16550_ops); |
| |
| void ns16550_init(struct ns16550_data *pd, paddr_t base) |
| { |
| pd->base.pa = base; |
| pd->chip.ops = &ns16550_ops; |
| |
| /* |
| * Do nothing, uart driver shared with normal world, |
| * everything for uart driver initialization is done in bootloader. |
| */ |
| } |