Commit 7cfb0435 authored Sep 03, 2008 by Thomas Gleixner

HPET: make minimum reprogramming delta useful



The minimum reprogramming delta was hardcoded in HPET ticks,
which is stupid as it does not work with faster running HPETs.
The C1E idle patches made this prominent on AMD/RS690 chipsets,
where the HPET runs with 25MHz. Set it to 5us which seems to be
a reasonable value and fixes the problems on the bug reporters
machines. We have a further sanity check now in the clock events,
which increases the delta when it is not sufficient.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Tested-by: Dmitry Nezhevenko <dion@inhex.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent 1fb9b7d2

arch/x86/kernel/hpet.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -210,8 +210,8 @@ static void hpet_legacy_clockevent_register(void)
		/* Calculate the min / max delta */
		hpet_clockevent.max_delta_ns = clockevent_delta2ns(0x7FFFFFFF,
		&hpet_clockevent);
		hpet_clockevent.min_delta_ns = clockevent_delta2ns(0x30,
		&hpet_clockevent);
		/* 5 usec minimum reprogramming delta. */
		hpet_clockevent.min_delta_ns = 5000;

		/*
		* Start hpet with the boot cpu mask and make it

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