[9fans] tech writer humor

[9fans] tech writer humor

[erik quanstrom]

ah yes, that clears it up

	19.4.22
	APICID
	This register uniquely identifies an APIC in the system. This register is not used by
	OS'es anymore and is still implemented in hardware because of FUD.

(Intel® 5520 chipset and Intel® 5500 chipset datasheet pub 321328)

- erik

Re: [9fans] tech writer humor

[ron minnich]

On Mon, Feb 21, 2011 at 5:45 PM, erik quanstrom <quanstro@quanstro.net> wrote:
> ah yes, that clears it up
>
>        19.4.22
>        APICID
>        This register uniquely identifies an APIC in the system. This register is not used by
>        OS'es anymore and is still implemented in hardware because of FUD.
>
> (Intel® 5520 chipset and Intel® 5500 chipset datasheet pub 321328)

Did intel claim that the OSes should be using ACPI? What do they use instead?

ron
p.s. I appreciate the humor but it does lead to a serious question.

Re: [9fans] tech writer humor

[erik quanstrom]

On Tue Feb 22 12:57:18 EST 2011, rminnich@gmail.com wrote:
> On Mon, Feb 21, 2011 at 5:45 PM, erik quanstrom <quanstro@quanstro.net> wrote:
> > ah yes, that clears it up
> >
> >        19.4.22
> >        APICID
> >        This register uniquely identifies an APIC in the system. This register is not used by
> >        OS'es anymore and is still implemented in hardware because of FUD.
> >
> > (Intel® 5520 chipset and Intel® 5500 chipset datasheet pub 321328)
>
> Did intel claim that the OSes should be using ACPI? What do they use instead?
>
> ron
> p.s. I appreciate the humor but it does lead to a serious question.

afik, acpi has nothing to do with this problem.  i believe this particular
tech writer intends to claim that nobody uses physical addressing anymore.
but i believe bios still needs to use physical addressing before logical addressing
is established.  so i think the writer may be speaking a misleading half
of the whole story.

- erik

Re: [9fans] tech writer humor

[erik quanstrom]

> > >        19.4.22
> > >        APICID
> > >        This register uniquely identifies an APIC in the system. This register is not used by
> > >        OS'es anymore and is still implemented in hardware because of FUD.
> > >
> > > (Intel® 5520 chipset and Intel® 5500 chipset datasheet pub 321328)
> >
> > Did intel claim that the OSes should be using ACPI? What do they use instead?
> >
> > ron
> > p.s. I appreciate the humor but it does lead to a serious question.
>
> afik, acpi has nothing to do with this problem.  i believe this particular
> tech writer intends to claim that nobody uses physical addressing anymore.
> but i believe bios still needs to use physical addressing before logical addressing
> is established.  so i think the writer may be speaking a misleading half
> of the whole story.

i think i was unclear.  by physical vs. logical addressing i mean of course of
the various system apics, not of memory.

in any event, the logical addressing is the responsibility of the os, so acpi
doesn't provide it either.  (annoying how acpi and apic obvious anagrams.)

- erik

Re: [9fans] tech writer humor

[ron minnich]

let me ask the question again. I know what the difference between APIC
and ACPI means.

Why is it that they don't think anyone needs that register any more?
What are they suggesting people use instead?

ron

Re: [9fans] tech writer humor

[Devon H. O'Dell]

2011/2/22 ron minnich <rminnich@gmail.com>:
> let me ask the question again. I know what the difference between APIC
> and ACPI means.
>
> Why is it that they don't think anyone needs that register any more?
> What are they suggesting people use instead?

When I first read it, I thought it was funny. But then I realized it
didn't make much sense and was likely written by someone who was
confused by conflating multiple issues. Remember when the Pentium III
came out with the serial number in the cpuid instruction and people
went batshit insane because you could use it to track individual
computers? I'm wondering if that has any bearing on this -- but it's
almost exactly the opposite. It'd be insanely useful for software
licensing but the outcry made it basically a useless instruction. I
wonder if a tech writer saw a bunch of different stuff, did some
googling, and confused him / herself to death.

--dho

> ron
>
>

Re: [9fans] tech writer humor

[erik quanstrom]

On Tue Feb 22 15:11:29 EST 2011, rminnich@gmail.com wrote:
> let me ask the question again. I know what the difference between APIC
> and ACPI means.

i wasn't implying that you didn't.  i was saying that i sometimes
think one and say the other.

> Why is it that they don't think anyone needs that register any more?
> What are they suggesting people use instead?

good question.  as i said before, i have to chalk it up to
hurried documentation.  i'm quite sure apic ids are still
important.

- erik

Re: [9fans] tech writer humor

[Nemo]

apic ids can be found in the madt table, from acpi, iirc.

On Feb 22, 2011, at 9:27 PM, erik quanstrom <quanstro@quanstro.net> wrote:

> On Tue Feb 22 15:11:29 EST 2011, rminnich@gmail.com wrote:
>> let me ask the question again. I know what the difference between APIC
>> and ACPI means.
>
> i wasn't implying that you didn't.  i was saying that i sometimes
> think one and say the other.
>
>> Why is it that they don't think anyone needs that register any more?
>> What are they suggesting people use instead?
>
> good question.  as i said before, i have to chalk it up to
> hurried documentation.  i'm quite sure apic ids are still
> important.
>
> - erik
>

Re: [9fans] tech writer humor

[Lyndon Nerenberg (VE6BBM/VE7TFX)]

> apic ids can be found in the madt table, from acpi, iirc.

Heh.  You assume a correct ACPI BIOS implementation.  The worst
offenders I've seen have been Intel-designed motherboards :-P

Re: [9fans] tech writer humor

[erik quanstrom]

On Tue Feb 22 15:48:01 EST 2011, lyndon@orthanc.ca wrote:
> Heh.  You assume a correct ACPI BIOS implementation.  The worst
> offenders I've seen have been Intel-designed motherboards :-P

On Tue Feb 22 15:39:49 EST 2011, nemo.mbox@gmail.com wrote:
> apic ids can be found in the madt table, from acpi, iirc.
>

neither of these comments apply to the registers in question.  the registers
in question are the running configuration of the i/o apic in the intel
IOH-36D.  the madt table or the mp tables reflect a snaphot of *all*
the i/o apics and lapics in the system at the time when bios handed
control over to the operating system (sic.).

- erik

Re: [9fans] tech writer humor

[Lyndon Nerenberg (VE6BBM/VE7TFX)]

> the madt table or the mp tables reflect a snaphot of *all*
> the i/o apics and lapics in the system at the time when bios handed
> control over to the operating system (sic.).

No it doesn't. That's the bug in the BIOS -- it screws up building
the table.  I have an Intel mini-ITX board sitting in a box because
it's unuseable due to this bug.

Re: [9fans] tech writer humor

[erik quanstrom]

On Tue Feb 22 15:58:12 EST 2011, lyndon@orthanc.ca wrote:
> > the madt table or the mp tables reflect a snaphot of *all*
> > the i/o apics and lapics in the system at the time when bios handed
> > control over to the operating system (sic.).
>
> No it doesn't. That's the bug in the BIOS -- it screws up building
> the table.  I have an Intel mini-ITX board sitting in a box because
> it's unuseable due to this bug.

by definition, a bug in your bios doesn't change the specification,

- erik

Re: [9fans] tech writer humor

[Lyndon Nerenberg (VE6BBM/VE7TFX)]

> by definition, a bug in your bios doesn't change the specification,

True.  But a "specification" that doesn't run the same way on any
two models of motherboard isn't much of one.

Re: [9fans] tech writer humor

[ron minnich]

On Mon, Feb 21, 2011 at 5:45 PM, erik quanstrom <quanstro@quanstro.net> wrote:
> ah yes, that clears it up
>
>        19.4.22
>        APICID
>        This register uniquely identifies an APIC in the system. This register is not used by
>        OS'es anymore and is still implemented in hardware because of FUD.

So, my interpretation following the discussions: some over-zealous
hardware guy at Intel believes this register is no longer needed
because the OS should use BIOS services. Any OS that does not use BIOS
services is suffering from FUD, not a real need. I call bull****.

The BIOS services work well enough, of course, on most mainboards.
Intel mainboards, however, frequently screw the BIOS services and
tables up, such that the OS either can not boot or needs to poke
around the hardware and use, e.g., this register to find out what's
really going on. I'm pretty sure that there is a qualifying instance
of irony in here, though I'm relucant to say so since it's an overused
term.

It's another case of the Intel hardware designer disconnect from the
Intel mainboard designers and, following that, Intel's occasional
disconnect from reality ... I hit this all the time. (as do others;
one person I know was told by Intel that the _MP_ table on his
mainboard would get fixed only if the customer was willing to pay for
it. Nice.)

thanks

ron