FreeBSD kernel doesn't boot on FUJITSU PRIMERGY RX200 S5 server

Maxim Sobolev sobomax at
Tue Apr 27 21:06:30 UTC 2010

John Baldwin wrote:
> On Tuesday 27 April 2010 4:26:09 pm Maxim Sobolev wrote:
>> John Baldwin wrote:
>>> Hmm, I think you should definitely commit the atkbdc_isa.c change first of 
>>> all.  I'm still thinking about the other change.  I wonder if we can figure 
>>> out that a keyboard isn't present sooner somehow?  Do you know if the keyboard 
>>> appears to be present but just slow vs if the keyboard is eventually found to 
>>> not be present?
>> Our syscons does keyboard probing two times - once early during kernel 
>> initialization before most of the subsystems have been initialized yet, 
>> and then "real" probing later in boot process. Interesting thing is that 
>> initially keyboard looks present. Reading status port in 
>> atkbdc_configure() gives value other than 0xff, although reading is 
>> thousand times slower than usually. This causes syscons try attaching 
>> it. Even though reading status port works, apparently either emulation 
>> is not complete or there is some other issue, so that it never responds 
>> to some commands. Slow access and lack of response results in 
>> wait_for_data() function waiting several minutes instead of 200ms as 
>> designed. This what causes that 6-10 minutes delay in boot process.
> I believe the USB driver has disabled the keyboard emulation by the time the
> second probe happens in syscons.  Can you try disabling legacy USB support in
> the BIOS just to make sure that is what causes the delay?

Unfortunately it's not possible. Hosting provider doesn't allow me to 
have access to BIOS settings.

>> In fact I've also tried sending 0xAA command instead of just checking 
>> that value read from the status port is not 0xFF, and it actually 
>> completed fine at this point. The controller has returned 0x55 as 
>> expected. Therefore, I believe measuring inb() delay is the only 
>> reasonable way to avoid that big boot delay at this point.
>> Later on, when we probe/attach keyboard second time (in atkbdc_isa.c) 
>> reading status port returns 0xff, so the we can fail attachment process 
>> immediately. However, this is not a big issue since at this point 
>> reading from status port is as fast as any other ISA inb() operations, 
>> so it doesn't cause any noticeable delay.
>> Here is the latest version of the patch:
> Hmm, still has the issue that we can't assume a TSC on i386.  I would still
> commit the easy bits to change various '#if defined(__i386__)' to
> '#if defined(__i386__) || defined(__amd64__)' now.
> One thing that could make this cleaner would be to have a macro defined
> something like this in atkbdc.c:
> /* CPU will stay inside loops for 100msec at most. */
> #ifdef __amd64__
> #define	KBD_RETRY(kbd)		(100000 / ((KBDD_DELAYTIME * 2) + kbdc->read_delay))
> #else
> #define	KBD_RETRY(kbd)		(5000)
> #endif
> and then use 'KBD_RETRY(kbd)' to initialize 'retry' in various places.

Please take a closer look. Use of rdtsc() in this version is conditonal 
on __amd64__ only.


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