Console serial speed

Doug Ambrisko ambrisko at ambrisko.com
Thu Jul 31 14:04:47 PDT 2003


Russell Cattelan writes:
| On Wed, 2003-07-30 at 21:58, Doug Ambrisko wrote:
| > Russell Cattelan writes:
| > | How does one set the serial speed of the console.
| > | I changed the boot loader speed to 57600 in make.conf
| > | but the kernel seems to chose random speeds each time 
| > | it's booted.
| > | Sometimes it's 9600 sometimes it 115200 other times 
| > | it's 38400.
| > | 
| > | Note this is on 5.x current
| > 
| > You might want to check sys/isa/sio.c in function siocngetspeed.
| > I comment out the "return (rclk / (16UL * divisor));" on some of my
| > stable boxes.  I've seen a few motherboards that result in a messed
| > up console if I don't do it (ie. wrong speed).
|
| I changed the return val to be CONSPEED.
| The machine now boots with the console speed correctly set
| to 57600
| 
| Thanks... suppose a proper fix would be good :-)

I'm not sure what a proper fix would be.  We try to read the speed out
of the UART and it fails to get what it was set to.  This could be
broken hardware etc.  Personally I haven't had the motivation to figure
out why some machines fail and I just wacked the code to make it work
so I can actually fix the real problem I was working on!

Maybe some #define that could over-ride everything and just set might
be a fix for broken HW.

Doug A.


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