/*****************************************************************************
* arch/arm/src/armv7-m/up_itm.c
*
* Copyright (c) 2009 - 2013 ARM 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:
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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.
* - Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
* *
* 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 COPYRIGHT HOLDERS AND 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.
*
* Copyright (C) 2014 Pierre-noel Bouteville . All rights reserved.
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Authors: Pierre-noel Bouteville <pnb990@gmail.com>
* Gregory Nutt <gnutt@nuttx.org>
*
* 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.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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.
*
*****************************************************************************/
/*****************************************************************************
* Included Files
*****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include "up_arch.h"
#include "itm.h"
/*****************************************************************************
* Public Data
*****************************************************************************/
/*****************************************************************************
* Public Functions
*****************************************************************************/
/*****************************************************************************
* Name: itm_sendchar
*
* Description:
* The function transmits a character via the ITM channel 0, and
* - Just returns when no debugger is connected that has booked the output.
* - Is blocking when a debugger is connected, but the previous character
* sent has not been transmitted.
*
* Input Parameters:
* ch - Character to transmit.
*
* Returned Value:
* Character to transmit.
*
*****************************************************************************/
uint32_t itm_sendchar(uint32_t ch)
{
if ((getreg32(ITM_TCR) & ITM_TCR_ITMENA_Msk) && /* ITM enabled */
(getreg32(ITM_TER) & (1UL << 0))) /* ITM Port #0 enabled */
{
while (getreg32(ITM_PORT(0)) == 0);
putreg8((uint8_t)ch, ITM_PORT(0));
}
return ch;
}
/*****************************************************************************
* Name: itm_receivechar
*
* Description:
*
* Input Parameters:
* The function inputs a character via the external variable g_itm_rxbuffer.
*
* Returned Value:
* Received character or -1 No character pending.
*
*****************************************************************************/
int32_t itm_receivechar(void)
{
int32_t ch = -1; /* Assume no character available */
if (g_itm_rxbuffer != ITM_RXBUFFER_EMPTY)
{
ch = g_itm_rxbuffer;
g_itm_rxbuffer = ITM_RXBUFFER_EMPTY; /* Ready for next character */
}
return ch;
}
/*****************************************************************************
* Name: itm_checkchar
*
* Description:
*
* Input Parameters:
* The function checks whether a character is pending for reading in the
* variable g_itm_rxbuffer.
*
* Returned Value:
* 0 No character available.
* 1 Character available.
*
*****************************************************************************/
int32_t itm_checkchar (void)
{
return (g_itm_rxbuffer != ITM_RXBUFFER_EMPTY);
}
