x86_64: prepare apic code for clock events

Change __setup_APIC_LVTT so it takes the arguments which are necessary
for the later clock events switch.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>

1 files changed, 15 insertions, 8 deletions

diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c
index 48206bb8de1f..ce2f8015d5ce 100644
--- a/arch/x86/kernel/apic_64.c
+++ b/arch/x86/kernel/apic_64.c
@@ -759,14 +759,14 @@ void __init init_apic_mappings(void)
 
 #define APIC_DIVISOR 16
 
-static void __setup_APIC_LVTT(unsigned int clocks)
+static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
 {
         unsigned int lvtt_value, tmp_value;
-        int cpu = smp_processor_id();
-
-        lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
 
-        if (cpu_isset(cpu, timer_interrupt_broadcast_ipi_mask))
+        lvtt_value = LOCAL_TIMER_VECTOR;
+        if (!oneshot)
+                lvtt_value |= APIC_LVT_TIMER_PERIODIC;
+        if (!irqen)
                 lvtt_value |= APIC_LVT_MASKED;
 
         apic_write(APIC_LVTT, lvtt_value);
@@ -779,12 +779,14 @@ static void __setup_APIC_LVTT(unsigned int clocks)
                                 & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
                                 | APIC_TDR_DIV_16);
 
-        apic_write(APIC_TMICT, clocks/APIC_DIVISOR);
+        if (!oneshot)
+                apic_write(APIC_TMICT, clocks/APIC_DIVISOR);
 }
 
 static void setup_APIC_timer(unsigned int clocks)
 {
         unsigned long flags;
+        int irqen;
 
         local_irq_save(flags);
 
@@ -805,7 +807,10 @@ static void setup_APIC_timer(unsigned int clocks)
                         c2 |= inb_p(0x40) << 8;
                 } while (c2 - c1 < 300);
         }
-        __setup_APIC_LVTT(clocks);
+
+        irqen = ! cpu_isset(smp_processor_id(),
+                            timer_interrupt_broadcast_ipi_mask);
+        __setup_APIC_LVTT(clocks, 0, irqen);
         /* Turn off PIT interrupt if we use APIC timer as main timer.
            Only works with the PM timer right now
            TBD fix it for HPET too. */
@@ -843,8 +848,10 @@ static int __init calibrate_APIC_clock(void)
          * Put whatever arbitrary (but long enough) timeout
          * value into the APIC clock, we just want to get the
          * counter running for calibration.
+         *
+         * No interrupt enable !
          */
-        __setup_APIC_LVTT(4000000000);
+        __setup_APIC_LVTT(4000000000, 0, 0);
 
         apic_start = apic_read(APIC_TMCCT);
 #ifdef CONFIG_X86_PM_TIMER