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Commit dcc98416 authored by Aristeu Rozanski's avatar Aristeu Rozanski Committed by Ingo Molnar
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x86, perfctr: don't use CCCR_OVF_PMI1 on Pentium 4Ds 



Currently, setup_p4_watchdog() use CCCR_OVF_PMI1 to enable the counter
overflow interrupts to the second logical core. But this bit doesn't work
on Pentium 4 Ds (model 4, stepping 4) and this patch avoids its use on
these processors. Tested on 4 different machines that have this
specific model with success.

Signed-off-by: default avatarAristeu Rozanski <aris@redhat.com>
Cc: jvillalovos@redhat.com
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 975439fe

arch/x86/kernel/cpu/perfctr-watchdog.c

+7 −1
Original line number Diff line number Diff line
@@ -478,7 +478,13 @@ static int setup_p4_watchdog(unsigned nmi_hz) 
		perfctr_msr = MSR_P4_IQ_PERFCTR1;

		evntsel_msr = MSR_P4_CRU_ESCR0;

		cccr_msr = MSR_P4_IQ_CCCR1;

		cccr_val = P4_CCCR_OVF_PMI1 | P4_CCCR_ESCR_SELECT(4);



		/* Pentium 4 D processors don't support P4_CCCR_OVF_PMI1 */

		if (boot_cpu_data.x86_model == 4 && boot_cpu_data.x86_mask == 4)

			cccr_val = P4_CCCR_OVF_PMI0;

		else

			cccr_val = P4_CCCR_OVF_PMI1;

		cccr_val |= P4_CCCR_ESCR_SELECT(4);

	}



	evntsel = P4_ESCR_EVENT_SELECT(0x3F)