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/* SPDX-License-Identifier: BSD-2-Clause */
/*
* COPYRIGHT (c) 2010.
* Cobham Gaisler AB.
*
* 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 OWNER 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 <grlib/apbuart.h>
#include <rtems/score/cpuimpl.h>
void apbuart_outbyte_wait(const struct apbuart_regs *regs)
{
while ( (regs->status & APBUART_STATUS_TE) == 0 ) {
/* Lower bus utilization while waiting for UART */
_CPU_Instruction_no_operation();
_CPU_Instruction_no_operation();
_CPU_Instruction_no_operation();
_CPU_Instruction_no_operation();
_CPU_Instruction_no_operation();
_CPU_Instruction_no_operation();
_CPU_Instruction_no_operation();
_CPU_Instruction_no_operation();
}
}
void apbuart_outbyte_polled(struct apbuart_regs *regs, char ch)
{
apbuart_outbyte_wait(regs);
regs->data = (uint8_t) ch;
}
int apbuart_inbyte_nonblocking(struct apbuart_regs *regs)
{
/* Clear errors */
regs->status = ~APBUART_STATUS_ERR;
if ((regs->status & APBUART_STATUS_DR) == 0) {
return -1;
}
return (uint8_t) regs->data;
}
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