diff options
Diffstat (limited to 'sys/dev/ic/com_subr.c')
| -rw-r--r-- | sys/dev/ic/com_subr.c | 65 |
1 files changed, 64 insertions, 1 deletions
diff --git a/sys/dev/ic/com_subr.c b/sys/dev/ic/com_subr.c index a00a5e99780..40025dabfd8 100644 --- a/sys/dev/ic/com_subr.c +++ b/sys/dev/ic/com_subr.c @@ -1,4 +1,4 @@ -/* $OpenBSD: com_subr.c,v 1.2 2005/10/13 01:59:42 fgsch Exp $ */ +/* $OpenBSD: com_subr.c,v 1.3 2005/10/13 14:58:56 fgsch Exp $ */ /* * Copyright (c) 1997 - 1999, Jason Downs. All rights reserved. @@ -108,6 +108,7 @@ cdev_decl(com); #endif void com_enable_debugport(struct com_softc *); +void com_fifo_probe(struct com_softc *); #if defined(COM_CONSOLE) || defined(KGDB) void @@ -314,6 +315,10 @@ com_attach_subr(sc) if (sc->sc_fifolen == 0) sc->sc_fifolen = 1; /* default */ +#ifdef notyet + com_fifo_probe(sc); +#endif + /* clear and disable fifo */ bus_space_write_1(iot, ioh, com_fifo, FIFO_RCV_RST | FIFO_XMT_RST); (void)bus_space_read_1(iot, ioh, com_data); @@ -376,3 +381,61 @@ com_attach_subr(sc) com_enable_debugport(sc); #endif } + +void +com_fifo_probe(struct com_softc *sc) +{ + bus_space_handle_t ioh = sc->sc_ioh; + bus_space_tag_t iot = sc->sc_iot; + u_int8_t fifo, ier; + int timo, len; + + if (!ISSET(sc->sc_hwflags, COM_HW_FIFO)) + return; + + ier = 0; +#ifdef COM_PXA2X0 + if (sc->sc_uarttype == COM_UART_PXA2X0) + ier |= IER_EUART; +#endif + bus_space_write_1(iot, ioh, com_ier, ier); + bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB); + bus_space_write_1(iot, ioh, com_dlbl, 3); + bus_space_write_1(iot, ioh, com_dlbh, 0); + bus_space_write_1(iot, ioh, com_lcr, LCR_PNONE | LCR_8BITS); + bus_space_write_1(iot, ioh, com_mcr, MCR_LOOPBACK); + + fifo = FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST; + if (sc->sc_uarttype == COM_UART_TI16750) + fifo |= FIFO_ENABLE_64BYTE; + + bus_space_write_1(iot, ioh, com_fifo, fifo); + + for (len = 0; len < 256; len++) { + bus_space_write_1(iot, ioh, com_data, (len + 1)); + timo = 2000; + while (!ISSET(bus_space_read_1(iot, ioh, com_lsr), + LSR_TXRDY) && --timo) + delay(1); + if (!timo) + break; + } + + delay(100); + + for (len = 0; len < 256; len++) { + timo = 2000; + while (!ISSET(bus_space_read_1(iot, ioh, com_lsr), + LSR_RXRDY) && --timo) + delay(1); + if (!timo || bus_space_read_1(iot, ioh, com_data) != (len + 1)) + break; + } + + /* For safety, always use the smaller value. */ + if (sc->sc_fifolen > len) { + printf("%s: probed fifo depth: %d bytes\n", + sc->sc_dev.dv_xname, len); + sc->sc_fifolen = len; + } +} |