ChibiOS/ports/ARM7-AT91SAM7X/pal_lld.h

198 lines
6.8 KiB
C

/*
ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file ports/ARM7-AT91SAM7X/pal_lld.h
* @brief AT91SAM7X PIO low level driver
* @addtogroup AT91SAM7X_PAL
* @{
*/
#ifndef _PAL_LLD_H_
#define _PAL_LLD_H_
#ifndef AT91SAM7X256_H
#include "at91lib/AT91SAM7X256.h"
#endif
/*===========================================================================*/
/* I/O Ports Types and constants. */
/*===========================================================================*/
/**
* @brief Width, in bits, of an I/O port.
*/
#define PAL_IOPORTS_WIDTH 32
/**
* @brief Digital I/O port sized unsigned type.
*/
typedef uint32_t ioportmask_t;
/**
* @brief Port Identifier.
* @details This type can be a scalar or some kind of pointer, do not make
* any assumption about it, use the provided macros when populating
* variables of this type.
*/
typedef AT91PS_PIO ioportid_t;
/*===========================================================================*/
/* I/O Ports Identifiers. */
/*===========================================================================*/
/**
* @brief PIO port A identifier.
*/
#define IOPORT_A AT91C_BASE_PIOA
/**
* @brief PIO port B identifier.
*/
#define IOPORT_B AT91C_BASE_PIOB
/*===========================================================================*/
/* Implementation, some of the following macros could be implemented as */
/* functions, if so please put them in a file named pal_lld.c. */
/*===========================================================================*/
/**
* @brief Low level PAL subsystem initialization.
* @details Clocks are enabled and both PIO ports are reset to a known state
* and all pads are enabled a digital I/Os.
*
* @note The other PIO registers are not modified, the PIOs are supposed to
* have just been reset. The PIO_PSR is cleared because its status
* after the reset is not very clear in the documentation.
*/
#define pal_lld_init() { \
AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_PIOA) | (1 << AT91C_ID_PIOB); \
AT91C_BASE_PIOA->PIO_PER = 0xFFFFFFFF; \
AT91C_BASE_PIOB->PIO_PER = 0xFFFFFFFF; \
}
/**
* @brief Reads the physical I/O port states.
* @details This function is implemented by reading the PIO_PDSR register, the
* implementation has no side effects.
*
* @param[in] port the port identifier
* @return The port bits.
*
* @note This function is not meant to be invoked directly by the application
* code.
*/
#define pal_lld_readport(port) ((port)->PIO_PDSR)
/**
* @brief Reads the output latch.
* @details This function is implemented by reading the PIO_ODSR register, the
* implementation has no side effects.
*
* @param[in] port the port identifier
* @return The latched logical states.
*
* @note This function is not meant to be invoked directly by the application
* code.
*/
#define pal_lld_readlatch(port) ((port)->PIO_ODSR)
/**
* @brief Writes a bits mask on a I/O port.
* @details This function is implemented by writing the PIO_ODSR register, the
* implementation has no side effects.
*
* @param[in] port the port identifier
* @param[in] bits the bits to be written on the specified port
*
* @note This function is not meant to be invoked directly by the application
* code.
*/
#define pal_lld_writeport(port, bits) { \
(port)->PIO_ODSR = (bits); \
}
/**
* @brief Sets a bits mask on a I/O port.
* @details This function is implemented by writing the PIO_SODR register, the
* implementation has no side effects.
*
* @param[in] port the port identifier
* @param[in] bits the bits to be ORed on the specified port
*
* @note This function is not meant to be invoked directly by the application
* code.
*/
#define pal_lld_setport(port, bits) { \
(port)->PIO_SODR = (bits); \
}
/**
* @brief Clears a bits mask on a I/O port.
* @details This function is implemented by writing the PIO_CODR register, the
* implementation has no side effects.
*
* @param[in] port the port identifier
* @param[in] bits the bits to be cleared on the specified port
*
* @note This function is not meant to be invoked directly by the application
* code.
*/
#define pal_lld_clearport(port, bits) { \
(port)->PIO_CODR = (bits); \
}
/**
* @brief Writes a group of bits.
* @details This function is implemented by writing the PIO_OWER, PIO_ODSR and
* PIO_OWDR registers, the implementation is not atomic because the
* multiple accesses.
*
* @param[in] port the port identifier
* @param[in] mask the group mask
* @param[in] offset the group bit offset within the port
* @param[in] bits the bits to be written. Values exceeding the group width
* are masked.
*
* @note This function is not meant to be invoked directly by the application
* code.
*/
#define pal_lld_writegroup(port, mask, offset, bits) { \
(port)->PIO_OWER = (mask) << (offset); \
(port)->PIO_ODSR = (bits) << (offset); \
(port)->PIO_OWDR = (mask) << (offset); \
}
/**
* @brief Writes a logical state on an output pad.
*
* @param[in] port the port identifier
* @param[in] pad the pad number within the port
* @param[out] bit the logical value, the value must be @p 0 or @p 1
*
* @note This function is not meant to be invoked directly by the application
* code.
*/
#define pal_lld_writepad(port, pad, bit) pal_lld_writegroup(port, 1, pad, bit)
#endif /* _PAL_LLD_H_ */
/** @} */