x86: Add a few common Intel CPU functions

Add functions to query CPU information, needed for ACPI.

Signed-off-by: Simon Glass <sjg@chromium.org>

2 files changed, 113 insertions, 0 deletions

diff --git a/arch/x86/cpu/intel_common/cpu.c b/arch/x86/cpu/intel_common/cpu.c
index 509730aea9..cb4ef84013 100644
--- a/arch/x86/cpu/intel_common/cpu.c
+++ b/arch/x86/cpu/intel_common/cpu.c
@@ -12,6 +12,7 @@
 #include <dm.h>
 #include <errno.h>
 #include <log.h>
+#include <acpi/acpigen.h>
 #include <asm/cpu.h>
 #include <asm/cpu_common.h>
 #include <asm/intel_regs.h>
@@ -227,3 +228,66 @@ void cpu_set_eist(bool eist_status)
 		msr.lo &= ~MISC_ENABLE_ENHANCED_SPEEDSTEP;
 	msr_write(MSR_IA32_MISC_ENABLE, msr);
 }
+
+int cpu_get_coord_type(void)
+{
+	return HW_ALL;
+}
+
+int cpu_get_min_ratio(void)
+{
+	msr_t msr;
+
+	/* Get bus ratio limits and calculate clock speeds */
+	msr = msr_read(MSR_PLATFORM_INFO);
+
+	return (msr.hi >> 8) & 0xff;	/* Max Efficiency Ratio */
+}
+
+int cpu_get_max_ratio(void)
+{
+	u32 ratio_max;
+	msr_t msr;
+
+	if (cpu_config_tdp_levels()) {
+		/* Set max ratio to nominal TDP ratio */
+		msr = msr_read(MSR_CONFIG_TDP_NOMINAL);
+		ratio_max = msr.lo & 0xff;
+	} else {
+		msr = msr_read(MSR_PLATFORM_INFO);
+		/* Max Non-Turbo Ratio */
+		ratio_max = (msr.lo >> 8) & 0xff;
+	}
+
+	return ratio_max;
+}
+
+int cpu_get_bus_clock_khz(void)
+{
+	/*
+	 * CPU bus clock is set by default here to 100MHz. This function returns
+	 * the bus clock in KHz.
+	 */
+	return INTEL_BCLK_MHZ * 1000;
+}
+
+int cpu_get_power_max(void)
+{
+	int power_unit;
+	msr_t msr;
+
+	msr = msr_read(MSR_PKG_POWER_SKU_UNIT);
+	power_unit = 2 << ((msr.lo & 0xf) - 1);
+	msr = msr_read(MSR_PKG_POWER_SKU);
+
+	return (msr.lo & 0x7fff) * 1000 / power_unit;
+}
+
+int cpu_get_max_turbo_ratio(void)
+{
+	msr_t msr;
+
+	msr = msr_read(MSR_TURBO_RATIO_LIMIT);
+
+	return msr.lo & 0xff;
+}
diff --git a/arch/x86/include/asm/cpu_common.h b/arch/x86/include/asm/cpu_common.h
index cdd99a90b7..a7b7112d41 100644
--- a/arch/x86/include/asm/cpu_common.h
+++ b/arch/x86/include/asm/cpu_common.h
@@ -128,4 +128,53 @@ void cpu_set_eist(bool eist_status);
  */
 void cpu_set_p_state_to_turbo_ratio(void);
 
+/**
+ * cpu_get_coord_type() - Get the type of coordination for P-State transition
+ *
+ * See ACPI spec v6.3 section 8.4.6.5 _PSD (P-State Dependency)
+ *
+ * @return HW_ALL (always)
+ */
+int cpu_get_coord_type(void);
+
+/**
+ * cpu_get_min_ratio() - get minimum support frequency ratio for CPU
+ *
+ * @return minimum ratio
+ */
+int cpu_get_min_ratio(void);
+
+/**
+ * cpu_get_max_ratio() - get nominal TDP ration or max non-turbo ratio
+ *
+ * If a nominal TDP ratio is available, it is returned. Otherwise this returns
+ * the  maximum non-turbo frequency ratio for this processor
+ *
+ * @return max ratio
+ */
+int cpu_get_max_ratio(void);
+
+/**
+ * cpu_get_bus_clock_khz() - Get the bus clock frequency in KHz
+ *
+ * This is the value the clock ratio is multiplied with
+ *
+ * @return bus-block frequency in KHz
+ */
+int cpu_get_bus_clock_khz(void);
+
+/**
+ * cpu_get_power_max() - Get maximum CPU TDP
+ *
+ * @return maximum CPU TDP (Thermal-design power) in mW
+ */
+int cpu_get_power_max(void);
+
+/**
+ * cpu_get_max_turbo_ratio() - Get maximum turbo ratio
+ *
+ * @return maximum ratio
+ */
+int cpu_get_max_turbo_ratio(void);
+
 #endif