diff options
Diffstat (limited to 'sys/dev/sio')
| -rw-r--r-- | sys/dev/sio/sio.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/sys/dev/sio/sio.c b/sys/dev/sio/sio.c index 7e910d5..5bf2968 100644 --- a/sys/dev/sio/sio.c +++ b/sys/dev/sio/sio.c @@ -31,7 +31,7 @@ * SUCH DAMAGE. * * from: @(#)com.c 7.5 (Berkeley) 5/16/91 - * $Id: sio.c,v 1.191 1997/12/16 17:40:07 eivind Exp $ + * $Id: sio.c,v 1.192 1997/12/28 06:20:47 bde Exp $ */ #include "opt_comconsole.h" @@ -2635,10 +2635,11 @@ void siocnprobe(cp) struct consdev *cp; { + speed_t boot_speed; + u_char cfcr; struct isa_device *dvp; int s; struct siocnstate sp; - speed_t boot_speed; /* * Find our first enabled console, if any. If it is a high-level @@ -2666,6 +2667,24 @@ siocnprobe(cp) if (boot_speed) comdefaultrate = boot_speed; } + + /* + * Initialize the divisor latch. We can't rely on + * siocnopen() to do this the first time, since it + * avoids writing to the latch if the latch appears + * to have the correct value. Also, if we didn't + * just read the speed from the hardware, then we + * need to set the speed in hardware so that + * switching it later is null. + */ + cfcr = inb(siocniobase + com_cfcr); + outb(siocniobase + com_cfcr, CFCR_DLAB | cfcr); + outb(siocniobase + com_dlbl, + COMBRD(comdefaultrate) & 0xff); + outb(siocniobase + com_dlbh, + (u_int) COMBRD(comdefaultrate) >> 8); + outb(siocniobase + com_cfcr, cfcr); + siocnopen(&sp); splx(s); if (!COM_LLCONSOLE(dvp)) { |
