From 836c129de971d526b6e85b8ad760bd635a00215e Mon Sep 17 00:00:00 2001 From: Cyrill Gorcunov Date: Tue, 15 Jul 2008 21:02:55 +0400 Subject: [PATCH] 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: Cyrill Gorcunov Cc: Cyrill Gorcunov Cc: macro@linux-mips.org Cc: yhlu.kernel@gmail.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/apic_32.c | 93 +++++++++++++++++++++------------------ 1 file changed, 50 insertions(+), 43 deletions(-) diff --git a/arch/x86/kernel/apic_32.c b/arch/x86/kernel/apic_32.c index 2bc1186cc95..d2a7eb511d6 100644 --- a/arch/x86/kernel/apic_32.c +++ b/arch/x86/kernel/apic_32.c @@ -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"); @@ -540,22 +514,55 @@ 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) - return; - } else { - /* - * If nmi_watchdog is set to IO_APIC, we need the - * PIT/HPET going. Otherwise register lapic as a dummy - * device. - */ - if (nmi_watchdog != NMI_IO_APIC) - lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY; - else - printk(KERN_WARNING "APIC timer registered as dummy," - " due to nmi_watchdog=%d!\n", nmi_watchdog); + 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"); + + 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 + * device. + */ + if (nmi_watchdog != NMI_IO_APIC) + lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY; + 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(); } -- 2.41.1