diff options
| author | marcel <marcel@FreeBSD.org> | 2009-04-08 00:14:06 +0000 |
|---|---|---|
| committer | marcel <marcel@FreeBSD.org> | 2009-04-08 00:14:06 +0000 |
| commit | d6a5c8810df83f81cd0e745553665359be0abfc1 (patch) | |
| tree | e4d6f8709d7f3a10be086c4fd72f1db98ce562a4 /sys/dev/uart/uart_dev_ns8250.c | |
| parent | 2444e34b785a96d6ce99f6cdbb9e60bb81ab4ebb (diff) | |
| download | FreeBSD-src-d6a5c8810df83f81cd0e745553665359be0abfc1.zip FreeBSD-src-d6a5c8810df83f81cd0e745553665359be0abfc1.tar.gz | |
Fix hangs caused by hardware that signals receive errors
(framing, parity, etc), but does not indicate characters
being received. Since no chracters have been received,
ignore the line errors.
PR: 131006
MFC after: 3 days
Diffstat (limited to 'sys/dev/uart/uart_dev_ns8250.c')
| -rw-r--r-- | sys/dev/uart/uart_dev_ns8250.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/sys/dev/uart/uart_dev_ns8250.c b/sys/dev/uart/uart_dev_ns8250.c index 81642b2..c01fd61 100644 --- a/sys/dev/uart/uart_dev_ns8250.c +++ b/sys/dev/uart/uart_dev_ns8250.c @@ -50,14 +50,16 @@ __FBSDID("$FreeBSD$"); static void ns8250_clrint(struct uart_bas *bas) { - uint8_t iir; + uint8_t iir, lsr; iir = uart_getreg(bas, REG_IIR); while ((iir & IIR_NOPEND) == 0) { iir &= IIR_IMASK; - if (iir == IIR_RLS) - (void)uart_getreg(bas, REG_LSR); - else if (iir == IIR_RXRDY || iir == IIR_RXTOUT) + if (iir == IIR_RLS) { + lsr = uart_getreg(bas, REG_LSR); + if (lsr & (LSR_BI|LSR_FE|LSR_PE)) + (void)uart_getreg(bas, REG_DATA); + } else if (iir == IIR_RXRDY || iir == IIR_RXTOUT) (void)uart_getreg(bas, REG_DATA); else if (iir == IIR_MLSC) (void)uart_getreg(bas, REG_MSR); @@ -587,7 +589,6 @@ ns8250_bus_ipend(struct uart_softc *sc) ipend = 0; if (iir & IIR_RXRDY) { lsr = uart_getreg(bas, REG_LSR); - uart_unlock(sc->sc_hwmtx); if (lsr & LSR_OE) ipend |= SER_INT_OVERRUN; if (lsr & LSR_BI) @@ -595,12 +596,14 @@ ns8250_bus_ipend(struct uart_softc *sc) if (lsr & LSR_RXRDY) ipend |= SER_INT_RXREADY; } else { - uart_unlock(sc->sc_hwmtx); if (iir & IIR_TXRDY) ipend |= SER_INT_TXIDLE; else ipend |= SER_INT_SIGCHG; } + if (ipend == 0) + ns8250_clrint(bas); + uart_unlock(sc->sc_hwmtx); return ((sc->sc_leaving) ? 0 : ipend); } |
