nuttx/arch/arm/src/samd/sam_sercom.h
2014-02-20 09:59:54 -06:00

145 lines
5.3 KiB
C

/****************************************************************************
* arch/arm/src/samd/sam_sercom.h
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: 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.
*
****************************************************************************/
#ifndef __ARCH_ARM_SRC_SAMD_SAM_SERCOM_H
#define __ARCH_ARM_SRC_SAMD_SAM_SERCOM_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdbool.h>
#include "up_arch.h"
#include "sam_config.h"
#include "chip/sam_pm.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Public Types
****************************************************************************/
/****************************************************************************
* Public Data
****************************************************************************/
#ifndef __ASSEMBLY__
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: sercom_enable
*
* Description:
* Enable clocking to a SERCOM module in PM
*
* Assumptions/Limitation:
* This operation is global and non-atomic. The caller should disable
* interrupts prior to calling this function.
*
****************************************************************************/
static inline void sercom_enable(int sercom)
{
uint32_t regval;
/* Enable clocking to the SERCOM module in PM */
regval = getreg32(SAM_PM_APBCMASK);
regval |= PM_APBCMASK_SERCOM(sercom);
putreg32(regval, SAM_PM_APBCMASK);
}
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: sercom_coreclk_configure
*
* Description:
* Configure the SERCOM core source clock.
*
* Two generic clocks are used by the SERCOM: GCLK_SERCOMx_CORE and
* GCLK_SERCOMx_SLOW. The core clock (GCLK_SERCOMx_CORE) is required to
* clock the SERCOM while operating as a master, while the slow clock
* (GCLK_SERCOM_SLOW) is only required for certain functions. SERCOM
* modules must share the same slow GCLK channel ID.
*
* The baud-rate generator runs off the GCLK_SERCOMx_CORE clock (or,
* optionally, external clock).
*
****************************************************************************/
void sercom_coreclk_configure(int sercom, int gclkgen, bool wrlock);
/****************************************************************************
* Name: sercom_slowclk_configure
*
* Description:
* Configure the SERCOM slow source clock.
*
* Two generic clocks are used by the SERCOM: GCLK_SERCOMx_CORE and
* GCLK_SERCOMx_SLOW. The core clock (GCLK_SERCOMx_CORE) is required to
* clock the SERCOM while operating as a master, while the slow clock
* (GCLK_SERCOM_SLOW) is only required for certain functions. SERCOM
* modules must share the same slow GCLK channel ID.
*
****************************************************************************/
void sercom_slowclk_configure(int gclkgen);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __ASSEMBLY__ */
#endif /* __ARCH_ARM_SRC_SAMD_SAM_SERCOM_H */