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/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @ingroup RTEMSBSPsPowerPCMPC55XX
*
* @brief Enhanced Modular Input Output Subsystem (eMIOS).
*/
/*
* Copyright (C) 2009, 2011 embedded brains GmbH & Co. KG
*
* 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 <mpc55xx/emios.h>
#ifdef MPC55XX_HAS_EMIOS
/**
* @brief Initialize the eMIOS module.
*
* The module is enabled. It is configured to use the internal clock. The
* global prescaler value is set to @a prescaler. If the value is greater than
* the maximum the maxium value will be used instead. A prescaler value of
* zero disables the clock.
*
* @note No protection against concurrent execution.
*/
void mpc55xx_emios_initialize( unsigned prescaler)
{
union EMIOS_MCR_tag mcr = MPC55XX_ZERO_FLAGS;
/* Enable module */
mcr.B.MDIS = 0;
/* Disable debug mode */
mcr.B.FRZ = 1;
/* Enable global time base */
mcr.B.GTBE = 1;
/* Disable global prescaler (= disable clock) */
mcr.B.GPREN = 0;
/* Set MCR */
EMIOS.MCR.R = mcr.R;
/* Set OUDR */
EMIOS.OUDR.R = 0;
/* Set global prescaler value */
mpc55xx_emios_set_global_prescaler( prescaler);
}
/**
* @brief Returns the global prescaler value of the eMIOS module.
*/
unsigned mpc55xx_emios_global_prescaler( void)
{
union EMIOS_MCR_tag mcr = EMIOS.MCR;
if (mcr.B.GPREN != 0) {
return mcr.B.GPRE + 1;
} else {
return 0;
}
}
/**
* @brief Sets the global prescaler value of the eMIOS module.
*
* The global prescaler value is set to @a prescaler. If the value is greater
* than the maximum the maxium value will be used instead. A prescaler value
* of zero disables the clock.
*
* @note No protection against concurrent execution.
*/
void mpc55xx_emios_set_global_prescaler( unsigned prescaler)
{
union EMIOS_MCR_tag mcr = EMIOS.MCR;
/* Enable or disable the global prescaler */
mcr.B.GPREN = prescaler > 0 ? 1 : 0;
/* Set global prescaler value */
if (prescaler > 256) {
prescaler = 256;
} else if (prescaler < 1) {
prescaler = 1;
}
mcr.B.GPRE = prescaler - 1;
/* Set MCR */
EMIOS.MCR.R = mcr.R;
}
#endif /* MPC55XX_HAS_EMIOS */
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