summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/cpu/interrupts.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
index e788715..dd30a05 100644
--- a/arch/x86/cpu/interrupts.c
+++ b/arch/x86/cpu/interrupts.c
@@ -34,6 +34,8 @@
#include <asm/io.h>
#include <asm/processor-flags.h>
#include <linux/compiler.h>
+#include <asm/msr.h>
+#include <asm/u-boot-x86.h>
#define DECLARE_INTERRUPT(x) \
".globl irq_"#x"\n" \
@@ -615,3 +617,32 @@ asm(".globl irq_common_entry\n" \
DECLARE_INTERRUPT(253) \
DECLARE_INTERRUPT(254) \
DECLARE_INTERRUPT(255));
+
+#if defined(CONFIG_INTEL_CORE_ARCH)
+/*
+ * Get the number of CPU time counter ticks since it was read first time after
+ * restart. This yields a free running counter guaranteed to take almost 6
+ * years to wrap around even at 100GHz clock rate.
+ */
+u64 get_ticks(void)
+{
+ static u64 tick_base;
+ u64 now_tick = rdtsc();
+
+ if (!tick_base)
+ tick_base = now_tick;
+
+ return now_tick - tick_base;
+}
+
+#define PLATFORM_INFO_MSR 0xce
+
+unsigned long get_tbclk(void)
+{
+ u32 ratio;
+ u64 platform_info = native_read_msr(PLATFORM_INFO_MSR);
+
+ ratio = (platform_info >> 8) & 0xff;
+ return 100 * 1000 * 1000 * ratio; /* 100MHz times Max Non Turbo ratio */
+}
+#endif