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// 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.
*/
}
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