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SubjectRe: [PATCH] Typo in x86 apic.c with DIVISOR setup

* Cyrill Gorcunov <gorcunov@gmail.com> wrote:

> Ah, it was CONFG who is guilty :) This is true indeed, thanks!

yeah.

> But here is not the same
>
> apic_write(APIC_TDCR,
> (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
> - APIC_TDR_DIV_16);
> + APIC_TDR_DIV);
>
> On x86_64 it will be 1 now but we've used 16 for a long time in
> purpose to slowdown processor's bus CLKs from APIC point of view. So I
> don't think it's good idea to change it now. If we start using divisor
> 1 today -- it would work for some time 'till processor bus raised to
> the some speed when we'll get counter underflow before calibration
> finished.
>
> So could you please split the patch into two:
> 1) Plain CONFG typo fix (which is completely Ack'ed)
> 2) APIC divisor patch (which I'm not sure if we've to touch)

okay, since we typoed that CONFG thing (sidenote: we really need a
.config flag that will start a grep that fails the build if there's a
non-existent CONFIG option anywhere in the tree), we basically tested
the divisor of 16 on a wide range of boxes.

So .. how about just standardizing on the divisor of 16 on both 32-bit
and 64-bit?

Ingo


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