Commit 836c129d authored by Cyrill Gorcunov's avatar Cyrill Gorcunov Committed by Ingo Molnar
Browse files

x86: apic_32 - introduce calibrate_APIC_clock 



Introduce calibrate_APIC_clock so it could help in further 32/64bit
apic code merging.

Signed-off-by: default avatarCyrill Gorcunov <gorcunov@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Cc: yhlu.kernel@gmail.com
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 89b3b1f4

arch/x86/kernel/apic_32.c

+50 −43
Original line number Diff line number Diff line
@@ -369,12 +369,7 @@ static void __init lapic_cal_handler(struct clock_event_device *dev) 
	}

}



/*

 * Setup the boot APIC

 *

 * Calibrate and verify the result.

 */

void __init setup_boot_APIC_clock(void)

static int __init calibrate_APIC_clock(void)

{

	struct clock_event_device *levt = &__get_cpu_var(lapic_events);

	const long pm_100ms = PMTMR_TICKS_PER_SEC/10;
@@ -384,24 +379,6 @@ void __init setup_boot_APIC_clock(void) 
	long delta, deltapm;

	int pm_referenced = 0;



	/*

	 * The local apic timer can be disabled via the kernel

	 * commandline or from the CPU detection code. Register the lapic

	 * timer as a dummy clock event source on SMP systems, so the

	 * broadcast mechanism is used. On UP systems simply ignore it.

	 */

	if (local_apic_timer_disabled) {

		/* No broadcast on UP ! */

		if (num_possible_cpus() > 1) {

			lapic_clockevent.mult = 1;

			setup_APIC_timer();

		}

		return;

	}



	apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"

		    "calibrating APIC timer ...\n");



	local_irq_disable();



	/* Replace the global interrupt handler */
@@ -486,8 +463,6 @@ void __init setup_boot_APIC_clock(void) 
		    calibration_result / (1000000 / HZ),

		    calibration_result % (1000000 / HZ));



	local_apic_timer_verify_ok = 1;



	/*

	 * Do a sanity check on the APIC calibration result

	 */
@@ -495,12 +470,11 @@ void __init setup_boot_APIC_clock(void) 
		local_irq_enable();

		printk(KERN_WARNING

		       "APIC frequency too slow, disabling apic timer\n");

		/* No broadcast on UP ! */

		if (num_possible_cpus() > 1)

			setup_APIC_timer();

		return;

		return -1;

	}



	local_apic_timer_verify_ok = 1;



	/* We trust the pm timer based calibration */

	if (!pm_referenced) {

		apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
@@ -540,10 +514,44 @@ void __init setup_boot_APIC_clock(void) 
	if (!local_apic_timer_verify_ok) {

		printk(KERN_WARNING

		       "APIC timer disabled due to verification failure.\n");

			return -1;

	}



	return 0;

}



/*

 * Setup the boot APIC

 *

 * Calibrate and verify the result.

 */

void __init setup_boot_APIC_clock(void)

{

	/*

	 * The local apic timer can be disabled via the kernel

	 * commandline or from the CPU detection code. Register the lapic

	 * timer as a dummy clock event source on SMP systems, so the

	 * broadcast mechanism is used. On UP systems simply ignore it.

	 */

	if (local_apic_timer_disabled) {

		/* No broadcast on UP ! */

		if (num_possible_cpus() == 1)

		if (num_possible_cpus() > 1) {

			lapic_clockevent.mult = 1;

			setup_APIC_timer();

		}

		return;

	} else {

	}



	apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"

		    "calibrating APIC timer ...\n");



	if (calibrate_APIC_clock()) {

		/* No broadcast on UP ! */

		if (num_possible_cpus() > 1)

			setup_APIC_timer();

		return;

	}



	/*

	 * If nmi_watchdog is set to IO_APIC, we need the

	 * PIT/HPET going.  Otherwise register lapic as a dummy
@@ -554,7 +562,6 @@ void __init setup_boot_APIC_clock(void) 
	else

		printk(KERN_WARNING "APIC timer registered as dummy,"

			" due to nmi_watchdog=%d!\n", nmi_watchdog);

	}



	/* Setup the lapic or request the broadcast */

	setup_APIC_timer();