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-rw-r--r--arch/i386/kernel/tsc.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/i386/kernel/tsc.c b/arch/i386/kernel/tsc.c
index 22931d24027..3082a418635 100644
--- a/arch/i386/kernel/tsc.c
+++ b/arch/i386/kernel/tsc.c
@@ -364,6 +364,25 @@ __cpuinit int unsynchronized_tsc(void)
return tsc_unstable;
}
+/*
+ * Geode_LX - the OLPC CPU has a possibly a very reliable TSC
+ */
+#ifdef CONFIG_MGEODE_LX
+/* RTSC counts during suspend */
+#define RTSC_SUSP 0x100
+
+static void __init check_geode_tsc_reliable(void)
+{
+ unsigned long val;
+
+ rdmsrl(MSR_GEODE_BUSCONT_CONF0, val);
+ if ((val & RTSC_SUSP))
+ clocksource_tsc.flags &= ~CLOCK_SOURCE_MUST_VERIFY;
+}
+#else
+static inline void check_geode_tsc_reliable(void) { }
+#endif
+
static int __init init_tsc_clocksource(void)
{
@@ -372,6 +391,7 @@ static int __init init_tsc_clocksource(void)
dmi_check_system(bad_tsc_dmi_table);
unsynchronized_tsc();
+ check_geode_tsc_reliable();
current_tsc_khz = tsc_khz;
clocksource_tsc.mult = clocksource_khz2mult(current_tsc_khz,
clocksource_tsc.shift);