diff options
| author | Marcus Glocker <mglocker@cvs.openbsd.org> | 2016-08-15 04:32:58 +0000 |
|---|---|---|
| committer | Marcus Glocker <mglocker@cvs.openbsd.org> | 2016-08-15 04:32:58 +0000 |
| commit | 944f9acec028c87dfe6b5b041678e8c962a2434b (patch) | |
| tree | 2a6ba3727b79cecfd28bc0bb70fb4feabff6ffc9 /sys | |
| parent | 057c5d3faa6fa4ee7301b99cab0a901d45277b09 (diff) | |
Drain FIFOs on init same as com(4) does it and reduce the RX FIFO interrupt
trigger to 1 character. This fixes a hang seen on the allwinner,sun5i-r8
board during boot when the driver switches to interrupts and no terminal
is attached.
ok kettenis
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/arch/armv7/sunxi/sxiuart.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/sys/arch/armv7/sunxi/sxiuart.c b/sys/arch/armv7/sunxi/sxiuart.c index 269af78ca4b..8944ee1e2ea 100644 --- a/sys/arch/armv7/sunxi/sxiuart.c +++ b/sys/arch/armv7/sunxi/sxiuart.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sxiuart.c,v 1.12 2016/08/12 16:09:37 kettenis Exp $ */ +/* $OpenBSD: sxiuart.c,v 1.13 2016/08/15 04:32:57 mglocker Exp $ */ /* * Copyright (c) 2005 Dale Rahn <drahn@motorola.com> * Copyright (c) 2013 Artturi Alm @@ -660,11 +660,18 @@ sxiuartopen(dev_t dev, int flag, int mode, struct proc *p) iot = sc->sc_iot; ioh = sc->sc_ioh; - bus_space_write_1(iot, ioh, SXIUART_FCR, FIFOE | FIFO_RXT2); - delay(100); - while (ISSET(bus_space_read_1(iot, ioh, SXIUART_LSR), - LSR_RXRDY)) + /* (Re)enable and drain FIFOs. */ + for (;;) { + bus_space_write_1(iot, ioh, SXIUART_FCR, 0); + delay(100); (void)bus_space_read_1(iot, ioh, SXIUART_RBR); + bus_space_write_1(iot, ioh, SXIUART_FCR, + FIFOE | FIFO_RXT0); + delay(100); + if (!ISSET(bus_space_read_1(iot, ioh, SXIUART_LSR), + LSR_RXRDY)) + break; + } sc->sc_mcr = MCR_DTR | MCR_RTS | MCR_IENABLE; bus_space_write_1(iot, ioh, SXIUART_MCR, sc->sc_mcr); |