3 files changed, 10 insertions, 8 deletions
diff --git a/src/soc/intel/apollolake/Kconfig b/src/soc/intel/apollolake/Kconfig
index c1b5252aa8..69d42bdf19 100644
--- a/src/soc/intel/apollolake/Kconfig
+++ b/src/soc/intel/apollolake/Kconfig
@@ -157,6 +157,9 @@ config SOC_INTEL_COMMON_BLOCK_GSPI_CLOCK_MHZ
 	int
 	default 100
 
+config CPU_XTAL_HZ
+	default 19200000
+
 config DRIVERS_I2C_DESIGNWARE_CLOCK_MHZ
 	int
 	default 133
diff --git a/src/soc/intel/apollolake/include/soc/cpu.h b/src/soc/intel/apollolake/include/soc/cpu.h
index 490820c3f6..38b830a16f 100644
--- a/src/soc/intel/apollolake/include/soc/cpu.h
+++ b/src/soc/intel/apollolake/include/soc/cpu.h
@@ -6,9 +6,6 @@
 #include <cpu/x86/msr.h>
 #include <intelblocks/msr.h>
 
-/* Common Timer Copy (CTC) frequency - 19.2MHz. */
-#define CTC_FREQ		19200000
-
 struct device;
 void apollolake_init_cpus(struct device *dev);
 void mainboard_devtree_update(struct device *dev);
diff --git a/src/soc/intel/apollolake/pmutil.c b/src/soc/intel/apollolake/pmutil.c
index c6d2eec791..e0de93eae4 100644
--- a/src/soc/intel/apollolake/pmutil.c
+++ b/src/soc/intel/apollolake/pmutil.c
@@ -180,15 +180,17 @@ int soc_prev_sleep_state(const struct chipset_power_state *ps,
 
 void enable_pm_timer_emulation(void)
 {
-	/* ACPI PM timer emulation */
 	msr_t msr;
+
+	if (!CONFIG_CPU_XTAL_HZ)
+		return;
+
 	/*
 	 * The derived frequency is calculated as follows:
-	 *    (CTC_FREQ * msr[63:32]) >> 32 = target frequency.
-	 * Back solve the multiplier so the 3.579545MHz ACPI timer
-	 * frequency is used.
+	 * (clock * msr[63:32]) >> 32 = target frequency.
+	 * Back solve the multiplier so the 3.579545MHz ACPI timer frequency is used.
 	 */
-	msr.hi = (3579545ULL << 32) / CTC_FREQ;
+	msr.hi = (3579545ULL << 32) / CONFIG_CPU_XTAL_HZ;
 	/* Set PM1 timer IO port and enable */
 	msr.lo = EMULATE_PM_TMR_EN | (ACPI_BASE_ADDRESS + R_ACPI_PM1_TMR);
 	wrmsr(MSR_EMULATE_PM_TIMER, msr);