diff options
| author | grehan <grehan@FreeBSD.org> | 2012-04-12 18:46:48 +0000 |
|---|---|---|
| committer | grehan <grehan@FreeBSD.org> | 2012-04-12 18:46:48 +0000 |
| commit | 476cf9ae6e212aca23d7b039a9d05a76a21fbf33 (patch) | |
| tree | 294c5abbdb85706a536e44ca167e0d870538f4de /sys/dev/uart | |
| parent | 4a73b1171086162f4344312ca649185f15985512 (diff) | |
| download | FreeBSD-src-476cf9ae6e212aca23d7b039a9d05a76a21fbf33.zip FreeBSD-src-476cf9ae6e212aca23d7b039a9d05a76a21fbf33.tar.gz | |
Complete polled-mode operation by using a callout if the device will be
used in polled-mode. The callout invokes uart_intr, which rearms the timeout.
Implemented for bhyve, but generically useful for e.g. embedded bringup
when the interrupt controller hasn't been setup, or if it's not deemed
worthy to wire an interrupt line from a serial port.
Submitted by: neel
Reviewed by: marcel
Obtained from: NetApp
MFC after: 3 weeks
Diffstat (limited to 'sys/dev/uart')
| -rw-r--r-- | sys/dev/uart/uart_bus.h | 1 | ||||
| -rw-r--r-- | sys/dev/uart/uart_core.c | 15 | ||||
| -rw-r--r-- | sys/dev/uart/uart_if.m | 1 |
3 files changed, 16 insertions, 1 deletions
diff --git a/sys/dev/uart/uart_bus.h b/sys/dev/uart/uart_bus.h index b1498f5..01752d0 100644 --- a/sys/dev/uart/uart_bus.h +++ b/sys/dev/uart/uart_bus.h @@ -87,6 +87,7 @@ struct uart_softc { 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. */ diff --git a/sys/dev/uart/uart_core.c b/sys/dev/uart/uart_core.c index fb1bb64..47d5f3d 100644 --- a/sys/dev/uart/uart_core.c +++ b/sys/dev/uart/uart_core.c @@ -58,6 +58,12 @@ SLIST_HEAD(uart_devinfo_list, uart_devinfo) uart_sysdevs = static MALLOC_DEFINE(M_UART, "UART", "UART driver"); +#ifndef UART_POLL_FREQ +#define UART_POLL_FREQ 50 +#endif +static int uart_poll_freq = UART_POLL_FREQ; +TUNABLE_INT("debug.uart_poll_freq", &uart_poll_freq); + void uart_add_sysdev(struct uart_devinfo *di) { @@ -257,6 +263,12 @@ uart_intr(void *arg) if (ipend & SER_INT_TXIDLE) uart_intr_txidle(sc); } + + if (sc->sc_polled) { + callout_reset(&sc->sc_timer, hz / uart_poll_freq, + (timeout_t *)uart_intr, sc); + } + return((flag)?FILTER_HANDLED:FILTER_STRAY); } @@ -440,8 +452,9 @@ uart_bus_attach(device_t dev) } } if (sc->sc_ires == NULL) { - /* XXX no interrupt resource. Force polled mode. */ + /* No interrupt resource. Force polled mode. */ sc->sc_polled = 1; + callout_init(&sc->sc_timer, 1); } sc->sc_rxbufsz = 384; diff --git a/sys/dev/uart/uart_if.m b/sys/dev/uart/uart_if.m index 0bb1454..bfac071 100644 --- a/sys/dev/uart/uart_if.m +++ b/sys/dev/uart/uart_if.m @@ -26,6 +26,7 @@ # $FreeBSD$ #include <sys/param.h> +#include <sys/systm.h> #include <sys/lock.h> #include <sys/mutex.h> #include <sys/bus.h> |
