kernel ignores kenv comconsole_speed?
stb at lassitu.de
Wed Oct 25 08:56:01 UTC 2006
Am 24.10.2006 um 16:41 schrieb Jeremy Chadwick:
> On Tue, Oct 24, 2006 at 09:41:57AM -0400, Vivek Khera wrote:
>>> Am 23.10.2006 um 17:46 schrieb Vivek Khera:
>>>> On Oct 20, 2006, at 6:59 AM, Stefan Bethke wrote:
>>> As I said, boot and loader are happily using 115200, but the kernel
>>> uses the compiled-in default. I'll file a PR the next few days,
>>> hopefully with a patch.
>> As I said, "works for me". I wonder what it is you are going to
>> patch? Did you try it with the separate -S option? Did it work?
> I think what Stefan refers to is the complex nature of how the
> serial port is initialised/"tinkered with" in stages.
[ Very good, but very long explanation of the various users of the
serial port omitted ]
> What I'd like to propose is similar to Stefan's recommendation:
> is there any way possible to:
> * Not touch the serial port AT ALL, EVER [...]
I'm not sure that would be so easy. However, CONSPEED is/was the
setting to be used if the actual setting cannot be determined when
sio initializes. I haven't researched if there ever was code that
tried to determine the sio settings when (re-)initializing. However,
/* default serial console speed if not set with sysctl or probed
from boot */
#define CONSPEED 9600
For me, probing from boot could just mean to initialize the speed
from kenv comconsole_speed if set, and fall back to CONSPEED
otherwise. I'll try to get around that on the weekend.
In current, imp re-enabled the commented-out tunable for
machdep.conspeed. Re-enabling that works without a problem, it seems
(cf. 1.463 of sio.c).
Stefan Bethke <stb at lassitu.de> Fon +49 170 346 0140
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