diff options
Diffstat (limited to 'usr.sbin/bhyve/uart_emul.c')
| -rw-r--r-- | usr.sbin/bhyve/uart_emul.c | 51 |
1 files changed, 34 insertions, 17 deletions
diff --git a/usr.sbin/bhyve/uart_emul.c b/usr.sbin/bhyve/uart_emul.c index 4242e5c..538bf58 100644 --- a/usr.sbin/bhyve/uart_emul.c +++ b/usr.sbin/bhyve/uart_emul.c @@ -272,6 +272,37 @@ uart_opentty(struct uart_softc *sc) assert(sc->mev != NULL); } +static uint8_t +modem_status(uint8_t mcr) +{ + uint8_t msr; + + if (mcr & MCR_LOOPBACK) { + /* + * In the loopback mode certain bits from the MCR are + * reflected back into MSR. + */ + msr = 0; + if (mcr & MCR_RTS) + msr |= MSR_CTS; + if (mcr & MCR_DTR) + msr |= MSR_DSR; + if (mcr & MCR_OUT1) + msr |= MSR_RI; + if (mcr & MCR_OUT2) + msr |= MSR_DCD; + } else { + /* + * Always assert DCD and DSR so tty open doesn't block + * even if CLOCAL is turned off. + */ + msr = MSR_DCD | MSR_DSR; + } + assert((msr & MSR_DELTA_MASK) == 0); + + return (msr); +} + /* * The IIR returns a prioritized interrupt reason: * - receive data available @@ -304,6 +335,7 @@ uart_reset(struct uart_softc *sc) divisor = DEFAULT_RCLK / DEFAULT_BAUD / 16; sc->dll = divisor; sc->dlh = divisor >> 16; + sc->msr = modem_status(sc->mcr); rxfifo_reset(sc, 1); /* no fifo until enabled by software */ } @@ -363,7 +395,7 @@ uart_write(struct uart_softc *sc, int offset, uint8_t value) uint8_t msr; pthread_mutex_lock(&sc->mtx); - + /* * Take care of the special case DLAB accesses first */ @@ -426,22 +458,7 @@ uart_write(struct uart_softc *sc, int offset, uint8_t value) case REG_MCR: /* Apply mask so that bits 5-7 are 0 */ sc->mcr = value & 0x1F; - - msr = 0; - if (sc->mcr & MCR_LOOPBACK) { - /* - * In the loopback mode certain bits from the - * MCR are reflected back into MSR - */ - if (sc->mcr & MCR_RTS) - msr |= MSR_CTS; - if (sc->mcr & MCR_DTR) - msr |= MSR_DSR; - if (sc->mcr & MCR_OUT1) - msr |= MSR_RI; - if (sc->mcr & MCR_OUT2) - msr |= MSR_DCD; - } + msr = modem_status(sc->mcr); /* * Detect if there has been any change between the |
