From: Cyrill Gorcunov <gorcunov@gmail.com>
Date: Tue, 15 Jul 2008 17:02:55 +0000 (+0400)
Subject: x86: apic_32 - introduce calibrate_APIC_clock
X-Git-Tag: firefly_0821_release~19458^2~8^3~4
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=836c129de971d526b6e85b8ad760bd635a00215e;p=firefly-linux-kernel-4.4.55.git
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 <gorcunov@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Cc: yhlu.kernel@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
diff --git a/arch/x86/kernel/apic_32.c b/arch/x86/kernel/apic_32.c
index 2bc1186cc95a..d2a7eb511d6b 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();
}