rtems/bsps/include/grlib/grslink.h

/* SPDX-License-Identifier: BSD-2-Clause */

/*
 * Header file for RTEMS GRSLINK SLINK master driver 
 * 
 * COPYRIGHT (c) 2009.
 * 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.
 */

#ifndef __GRSLINK_H__
#define __GRSLINK_H__

#ifdef __cplusplus
extern "C" {
#endif

/**** Configuration ****/
/* Collect statistics ? */
#define SLINK_COLLECT_STATISTICS

/* Frequency of SLINK SCLK */
#define SLINK_FREQ_HZ 6000000
/* Number of queues used in driver */
#define SLINK_NUMQUEUES 4

/* The four values below are only used in the demo software */
#define SLINK_CORE_REGBASE    0x80000600
#define SLINK_CORE_IRQ        6
#define IRQ_CNTRL_REG         0x80000200
#define IRQ_CNTRL_MASK_OFFSET 0x40

/* 
 * Structure returned by SLINK_statistics if SLINK_COLLECT_STATISTCS has
 * been defined
 */
typedef struct {
  unsigned int parerr;     /* Number of parity errors */
  unsigned int recov;      /* Number of receive overflows */
  unsigned int reads;      /* Number of completed READs */
  unsigned int writes;     /* Number of performed WRITES */
  unsigned int sequences;  /* Number of started SEQUENCEs */
  unsigned int seqcomp;    /* Number of completed SEQUENCEs */
  unsigned int interrupts; /* Number of INTERRUPT transfers */
  unsigned int lostwords;  /* Number of lost words due to full queue */
} SLINK_stats;

/**** SLINK status codes ****/
#define SLINK_ABORTED   0
#define SLINK_QFULL     1
#define SLINK_ACTIVE    2
#define SLINK_AMBAERR   3
#define SLINK_COMPLETED 4
#define SLINK_PARERR    5
#define SLINK_ROV       6 /* Only used internally in driver */

/**** SLINK master register fields *****/
/* Control register */
#define SLINK_C_SLEN_POS 16
#define SLINK_C_SRO      ( 1 << 8 )
#define SLINK_C_SCN_POS  4
#define SLINK_C_PAR      ( 1 << 3 )
#define SLINK_C_AS       ( 1 << 2 )
#define SLINK_C_SE       ( 1 << 1 )
#define SLINK_C_SLE      ( 1 << 0 )

/* Status register fields */
#define SLINK_S_SI_POS 16
#define SLINK_S_PERR   ( 1 << 7 )
#define SLINK_S_AERR   ( 1 << 6 )
#define SLINK_S_ROV    ( 1 << 5 )
#define SLINK_S_RNE    ( 1 << 4 )
#define SLINK_S_TNF    ( 1 << 3 )
#define SLINK_S_SC     ( 1 << 2 )
#define SLINK_S_SA     ( 1 << 1 )
#define SLINK_S_SRX    ( 1 << 0 )

/* Mask register fields */
#define SLINK_M_PERRE ( 1 << 7 )
#define SLINK_M_AERRE ( 1 << 6 )
#define SLINK_M_ROVE  ( 1 << 5 )
#define SLINK_M_RNEE  ( 1 << 4 )
#define SLINK_M_TNFE  ( 1 << 3 )
#define SLINK_M_SCE   ( 1 << 2 )
#define SLINK_M_SAE   ( 1 << 1 )
#define SLINK_M_SRXE  ( 1 << 0 )

/**** Macros ****/
/* Get channel field from received SLINK word */
#define SLINK_WRD_CHAN( x ) ( ( x >> 16 ) & 0xF )
/* Get IO card # from received SLINK word */
#define SLINK_WRD_CARDNUM( x ) ( ( x >> 21 ) & 0x3 )
/* Get data part from SLINK word */
#define SLINK_WRD_PAYLOAD( x ) ( x & 0xFFFF )

/* Checks status value to see if transmit queue has free slot */
#define SLINK_STS_TRANSFREE( x ) ( x & SLINK_S_TNF )
/* Get Sequence Index value */
#define SLINK_STS_SI( x ) ( ( x >> 16 ) & 0xFF )

/**** Function declarations, driver interface ****/
/* Initializes the SLINK core */
int SLINK_init(
  unsigned int nullwrd,
  int          parity,
  int          qsize,
  void ( *interrupt_trans_handler )( int ),
  void ( *sequence_callback )( int )
);

/* Enables the core */
void SLINK_start( void );

/* Disables the core */
void SLINK_stop( void );

/* Reads one word */
int SLINK_read( int data, int channel, int *reply );

/* Writes one word */
int SLINK_write( int data, int channel );

/* Peforms a SEQUENCE */
int SLINK_seqstart( int *a, int *b, int n, int channel, int reconly );

/* Aborts a SEQUENCE */
void SLINK_seqabort( void );

/* Status of current or last SEQUENCE */
int SLINK_seqstatus( void );

/* Number of words transferred in last SEQUENCE */
int SLINK_seqwrds( void );

/* Returns value of core's status register */
int SLINK_hwstatus( void );

/* Returns number of elements in queue associated with IO card */
int SLINK_queuestatus( int iocard );

/* Take first element from queue for IO card # 'iocard' */
int SLINK_dequeue( int iocard, int *elem );

/* Returns structure containing core driver statistics */
SLINK_stats *SLINK_statistics( void );

#ifdef __cplusplus
}
#endif

#endif /* __GRSLINK_H__ */