/* SPDX-License-Identifier: BSD-2-Clause */
/*
* GRCAN driver
*
* COPYRIGHT (c) 2007-2019.
* 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 GRCAN_DEFAULT_BAUD
/* default to 500kbits/s */
#define GRCAN_DEFAULT_BAUD 500000
#endif
#ifndef GRCAN_SAMPLING_POINT
#define GRCAN_SAMPLING_POINT 80
#endif
#define WRAP_AROUND_TX_MSGS 1
#define WRAP_AROUND_RX_MSGS 2
#define GRCAN_MSG_SIZE sizeof(struct grcan_msg)
struct grcan_msg {
unsigned int head[2];
unsigned char data[8];
};
struct grcan_config {
struct grcan_timing timing;
struct grcanfd_timing timing_fd;
struct grcan_selection selection;
int abort;
int silent;
};
struct grcan_priv {
struct drvmgr_dev *dev; /* Driver manager device */
char devName[52]; /* Device Name */
unsigned int baseaddr, ram_base;
struct grcan_regs *regs;
int irq;
int minor;
int open;
int started;
unsigned int channel;
int flushing;
unsigned int corefreq_hz;
int fd_capable;
/* Circular DMA buffers */
void *_rx, *_rx_hw;
void *_tx, *_tx_hw;
void *txbuf_adr;
void *rxbuf_adr;
struct grcan_msg *rx;
struct grcan_msg *tx;
unsigned int rxbuf_size; /* requested RX buf size in bytes */
unsigned int txbuf_size; /* requested TX buf size in bytes */
int txblock, rxblock;
int txcomplete, rxcomplete;
struct grcan_filter sfilter;
struct grcan_filter afilter;
int config_changed; /* 0=no changes, 1=changes ==> a Core reset is needed */
struct grcan_config config;
struct grcan_stats stats;
rtems_id rx_sem, tx_sem, txempty_sem, dev_sem;
SPIN_DECLARE(devlock);
};
#ifdef GRCAN_REG_BYPASS_CACHE
#define READ_REG(address) grlib_read_uncached32((unsigned int)(address))
#else
#define READ_REG(address) (*(volatile unsigned int *)(address))
#endif
#ifdef GRCAN_DMA_BYPASS_CACHE
#define READ_DMA_DOUBLE(address) grlib_read_uncached64((uint64_t *)(address))
#define READ_DMA_WORD(address) grlib_read_uncached32((unsigned int)(address))
#define READ_DMA_BYTE(address) grlib_read_uncached8((unsigned int)(address))
#else
#define READ_DMA_DOUBLE(address) (*(volatile uint64_t *)(address))
#define READ_DMA_WORD(address) (*(volatile unsigned int *)(address))
#define READ_DMA_BYTE(address) (*(volatile unsigned char *)(address))
#endif
extern int state2err[4];
extern struct grlib_canbtrs_ranges grcan_btrs_ranges;
extern struct grlib_canbtrs_ranges grcanfd_nom_btrs_ranges;
extern struct grlib_canbtrs_ranges grcanfd_fd_btrs_ranges;
int grcan_wait_rxdata(struct grcan_priv *pDev, int min);
int grcan_wait_txspace(struct grcan_priv *pDev, int min);
static inline unsigned int grcan_hw_rxavail(
unsigned int rp,
unsigned int wp,
unsigned int size)
{
if (rp == wp) {
/* read pointer and write pointer is equal only
* when RX buffer is empty.
*/
return 0;
}
if (wp > rp) {
return (wp - rp) / GRCAN_MSG_SIZE;
} else {
return (size - (rp - wp)) / GRCAN_MSG_SIZE;
}
}
static inline unsigned int grcan_hw_txspace(
unsigned int rp,
unsigned int wp,
unsigned int size)
{
unsigned int left;
if (rp == wp) {
/* read pointer and write pointer is equal only
* when TX buffer is empty.
*/
return size / GRCAN_MSG_SIZE - WRAP_AROUND_TX_MSGS;
}
/* size - 4 - abs(read-write) */
if (wp > rp) {
left = size - (wp - rp);
} else {
left = rp - wp;
}
return left / GRCAN_MSG_SIZE - WRAP_AROUND_TX_MSGS;
}
