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/*
* Copyright (C) 2015 Freescale Semiconductor, Inc.
* 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>
/* 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 */
void ns16550_flush(vaddr_t base)
{
while ((read8(base + UART_LSR) & UART_LSR_THRE) == 0)
;
}
void ns16550_putc(int ch, vaddr_t base)
{
ns16550_flush(base);
/* write out charset to Transmit-hold-register */
write8(ch, base + UART_THR);
}
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