1 files changed, 61 insertions, 11 deletions

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index fc3672a303d6..17409e8d1097 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -17,6 +17,8 @@
 #include <asm/time.h>
 #include <asm/delay.h>
 #include <asm/hypervisor.h>
+#include <asm/nmi.h>
+#include <asm/x86_init.h>
 
 unsigned int __read_mostly cpu_khz;     /* TSC clocks / usec, not used here */
 EXPORT_SYMBOL(cpu_khz);
@@ -400,15 +402,9 @@ unsigned long native_calibrate_tsc(void)
 {
         u64 tsc1, tsc2, delta, ref1, ref2;
         unsigned long tsc_pit_min = ULONG_MAX, tsc_ref_min = ULONG_MAX;
-        unsigned long flags, latch, ms, fast_calibrate, hv_tsc_khz;
+        unsigned long flags, latch, ms, fast_calibrate;
         int hpet = is_hpet_enabled(), i, loopmin;
 
-        hv_tsc_khz = get_hypervisor_tsc_freq();
-        if (hv_tsc_khz) {
-                printk(KERN_INFO "TSC: Frequency read from the hypervisor\n");
-                return hv_tsc_khz;
-        }
-
         local_irq_save(flags);
         fast_calibrate = quick_pit_calibrate();
         local_irq_restore(flags);
@@ -566,7 +562,7 @@ int recalibrate_cpu_khz(void)
         unsigned long cpu_khz_old = cpu_khz;
 
         if (cpu_has_tsc) {
-                tsc_khz = calibrate_tsc();
+                tsc_khz = x86_platform.calibrate_tsc();
                 cpu_khz = tsc_khz;
                 cpu_data(0).loops_per_jiffy =
                         cpufreq_scale(cpu_data(0).loops_per_jiffy,
@@ -860,15 +856,71 @@ static void __init init_tsc_clocksource(void)
         clocksource_register(&clocksource_tsc);
 }
 
+#ifdef CONFIG_X86_64
+/*
+ * calibrate_cpu is used on systems with fixed rate TSCs to determine
+ * processor frequency
+ */
+#define TICK_COUNT 100000000
+static unsigned long __init calibrate_cpu(void)
+{
+        int tsc_start, tsc_now;
+        int i, no_ctr_free;
+        unsigned long evntsel3 = 0, pmc3 = 0, pmc_now = 0;
+        unsigned long flags;
+
+        for (i = 0; i < 4; i++)
+                if (avail_to_resrv_perfctr_nmi_bit(i))
+                        break;
+        no_ctr_free = (i == 4);
+        if (no_ctr_free) {
+                WARN(1, KERN_WARNING "Warning: AMD perfctrs busy ... "
+                     "cpu_khz value may be incorrect.\n");
+                i = 3;
+                rdmsrl(MSR_K7_EVNTSEL3, evntsel3);
+                wrmsrl(MSR_K7_EVNTSEL3, 0);
+                rdmsrl(MSR_K7_PERFCTR3, pmc3);
+        } else {
+                reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i);
+                reserve_evntsel_nmi(MSR_K7_EVNTSEL0 + i);
+        }
+        local_irq_save(flags);
+        /* start measuring cycles, incrementing from 0 */
+        wrmsrl(MSR_K7_PERFCTR0 + i, 0);
+        wrmsrl(MSR_K7_EVNTSEL0 + i, 1 << 22 | 3 << 16 | 0x76);
+        rdtscl(tsc_start);
+        do {
+                rdmsrl(MSR_K7_PERFCTR0 + i, pmc_now);
+                tsc_now = get_cycles();
+        } while ((tsc_now - tsc_start) < TICK_COUNT);
+
+        local_irq_restore(flags);
+        if (no_ctr_free) {
+                wrmsrl(MSR_K7_EVNTSEL3, 0);
+                wrmsrl(MSR_K7_PERFCTR3, pmc3);
+                wrmsrl(MSR_K7_EVNTSEL3, evntsel3);
+        } else {
+                release_perfctr_nmi(MSR_K7_PERFCTR0 + i);
+                release_evntsel_nmi(MSR_K7_EVNTSEL0 + i);
+        }
+
+        return pmc_now * tsc_khz / (tsc_now - tsc_start);
+}
+#else
+static inline unsigned long calibrate_cpu(void) { return cpu_khz; }
+#endif
+
 void __init tsc_init(void)
 {
         u64 lpj;
         int cpu;
 
+        x86_init.timers.tsc_pre_init();
+
         if (!cpu_has_tsc)
                 return;
 
-        tsc_khz = calibrate_tsc();
+        tsc_khz = x86_platform.calibrate_tsc();
         cpu_khz = tsc_khz;
 
         if (!tsc_khz) {
@@ -876,11 +928,9 @@ void __init tsc_init(void)
                 return;
         }
 
-#ifdef CONFIG_X86_64
         if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) &&
                         (boot_cpu_data.x86_vendor == X86_VENDOR_AMD))
                 cpu_khz = calibrate_cpu();
-#endif
 
         printk("Detected %lu.%03lu MHz processor.\n",
                         (unsigned long)cpu_khz / 1000,