freebsd-nq/sys/dev/uart/uart_bus.h
John Baldwin 64c4dfcd26 Export a sysctl count of RX FIFO overrun events.
uart(4) backends currently detect RX FIFO overrun errors and report
them to the uart(4) core layer.  They are then reported to the generic
TTY layer which promptly ignores them.  As a result, there is
currently no good way to determine if a uart is experiencing RX FIFO
overruns.  One could add a generic per-tty counter, but there did not
appear to be a good way to export those.  Instead, add a sysctl under
the uart(4) sysctl tree to export the count of overruns.

Reviewed by:	brooks
MFC after:	2 weeks
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D24368
2020-04-13 20:59:09 +00:00

225 lines
6.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2003 Marcel Moolenaar
* All rights reserved.
*
* 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 AUTHOR ``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 AUTHOR 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.
*
* $FreeBSD$
*/
#ifndef _DEV_UART_BUS_H_
#define _DEV_UART_BUS_H_
#ifndef KLD_MODULE
#include "opt_uart.h"
#endif
#include <sys/serial.h>
#include <sys/timepps.h>
/* Drain and flush targets. */
#define UART_DRAIN_RECEIVER 0x0001
#define UART_DRAIN_TRANSMITTER 0x0002
#define UART_FLUSH_RECEIVER UART_DRAIN_RECEIVER
#define UART_FLUSH_TRANSMITTER UART_DRAIN_TRANSMITTER
/* Received character status bits. */
#define UART_STAT_BREAK 0x0100
#define UART_STAT_FRAMERR 0x0200
#define UART_STAT_OVERRUN 0x0400
#define UART_STAT_PARERR 0x0800
/* UART_IOCTL() requests */
#define UART_IOCTL_BREAK 1
#define UART_IOCTL_IFLOW 2
#define UART_IOCTL_OFLOW 3
#define UART_IOCTL_BAUD 4
/* UART quirk flags */
#define UART_F_BUSY_DETECT 0x1
#define UART_F_IGNORE_SPCR_REGSHFT 0x2
/*
* UART class & instance (=softc)
*/
struct uart_class {
KOBJ_CLASS_FIELDS;
struct uart_ops *uc_ops; /* Low-level console operations. */
u_int uc_range; /* Bus space address range. */
u_int uc_rclk; /* Default rclk for this device. */
u_int uc_rshift; /* Default regshift for this device. */
u_int uc_riowidth; /* Default reg io width for this device. */
};
struct uart_softc {
KOBJ_FIELDS;
struct uart_class *sc_class;
struct uart_bas sc_bas;
device_t sc_dev;
struct mtx sc_hwmtx_s; /* Spinlock protecting hardware. */
struct mtx *sc_hwmtx;
struct resource *sc_rres; /* Register resource. */
int sc_rrid;
int sc_rtype; /* SYS_RES_{IOPORT|MEMORY}. */
struct resource *sc_ires; /* Interrupt resource. */
void *sc_icookie;
int sc_irid;
struct callout sc_timer;
int sc_callout:1; /* This UART is opened for callout. */
int sc_fastintr:1; /* This UART uses fast interrupts. */
int sc_hwiflow:1; /* This UART has HW input flow ctl. */
int sc_hwoflow:1; /* This UART has HW output flow ctl. */
int sc_leaving:1; /* This UART is going away. */
int sc_opened:1; /* This UART is open for business. */
int sc_polled:1; /* This UART has no interrupts. */
int sc_txbusy:1; /* This UART is transmitting. */
int sc_isquelch:1; /* This UART has input squelched. */
int sc_testintr:1; /* This UART is under int. testing. */
struct uart_devinfo *sc_sysdev; /* System device (or NULL). */
int sc_altbrk; /* State for alt break sequence. */
uint32_t sc_hwsig; /* Signal state. Used by HW driver. */
/* Receiver data. */
uint16_t *sc_rxbuf;
int sc_rxbufsz;
int sc_rxput;
int sc_rxget;
int sc_rxfifosz; /* Size of RX FIFO. */
int sc_rxoverruns;
/* Transmitter data. */
uint8_t *sc_txbuf;
int sc_txdatasz;
int sc_txfifosz; /* Size of TX FIFO and buffer. */
/* Pulse capturing support (PPS). */
struct pps_state sc_pps;
int sc_pps_mode;
sbintime_t sc_pps_captime;
/* Upper layer data. */
void *sc_softih;
uint32_t sc_ttypend;
union {
/* TTY specific data. */
struct {
struct tty *tp;
} u_tty;
/* Keyboard specific data. */
struct {
} u_kbd;
} sc_u;
};
extern devclass_t uart_devclass;
extern const char uart_driver_name[];
int uart_bus_attach(device_t dev);
int uart_bus_detach(device_t dev);
int uart_bus_resume(device_t dev);
serdev_intr_t *uart_bus_ihand(device_t dev, int ipend);
int uart_bus_ipend(device_t dev);
int uart_bus_probe(device_t dev, int regshft, int regiowidth, int rclk, int rid, int chan, int quirks);
int uart_bus_sysdev(device_t dev);
void uart_sched_softih(struct uart_softc *, uint32_t);
int uart_tty_attach(struct uart_softc *);
int uart_tty_detach(struct uart_softc *);
struct mtx *uart_tty_getlock(struct uart_softc *);
void uart_tty_intr(void *arg);
/*
* Receive buffer operations.
*/
static __inline int
uart_rx_empty(struct uart_softc *sc)
{
return ((sc->sc_rxget == sc->sc_rxput) ? 1 : 0);
}
static __inline int
uart_rx_full(struct uart_softc *sc)
{
return ((sc->sc_rxput + 1 < sc->sc_rxbufsz) ?
(sc->sc_rxput + 1 == sc->sc_rxget) : (sc->sc_rxget == 0));
}
static __inline int
uart_rx_get(struct uart_softc *sc)
{
int ptr, xc;
ptr = sc->sc_rxget;
if (ptr == sc->sc_rxput)
return (-1);
xc = sc->sc_rxbuf[ptr++];
sc->sc_rxget = (ptr < sc->sc_rxbufsz) ? ptr : 0;
return (xc);
}
static __inline int
uart_rx_next(struct uart_softc *sc)
{
int ptr;
ptr = sc->sc_rxget;
if (ptr == sc->sc_rxput)
return (-1);
ptr += 1;
sc->sc_rxget = (ptr < sc->sc_rxbufsz) ? ptr : 0;
return (0);
}
static __inline int
uart_rx_peek(struct uart_softc *sc)
{
int ptr;
ptr = sc->sc_rxget;
return ((ptr == sc->sc_rxput) ? -1 : sc->sc_rxbuf[ptr]);
}
static __inline int
uart_rx_put(struct uart_softc *sc, int xc)
{
int ptr;
ptr = (sc->sc_rxput + 1 < sc->sc_rxbufsz) ? sc->sc_rxput + 1 : 0;
if (ptr == sc->sc_rxget)
return (ENOSPC);
sc->sc_rxbuf[sc->sc_rxput] = xc;
sc->sc_rxput = ptr;
return (0);
}
#endif /* _DEV_UART_BUS_H_ */