[PATCH v3 23/57] x86: Add a few common Intel CPU functions

Simon Glass
2020-09-06T21:43:31Z

Add functions to query CPU information, needed for ACPI.

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

(no changes since v1)

Changes in v1:
- Add more comments and rename cpu_get_bus_clock to cpu_get_bus_clock_khz()

arch/x86/cpu/intel_common/cpu.c | 64 +++++++++++++++++++++++++++++++
arch/x86/include/asm/cpu_common.h | 49 +++++++++++++++++++++++
include/acpi/acpigen.h | 12 ++++++
3 files changed, 125 insertions(+)

diff --git a/arch/x86/cpu/intel_common/cpu.c b/arch/x86/cpu/intel_common/cpu.c
index 509730aea96..cb4ef84013a 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 cdd99a90b76..a7b7112d417 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
diff --git a/include/acpi/acpigen.h b/include/acpi/acpigen.h
index 34b3115bc9c..c412898169e 100644
--- a/include/acpi/acpigen.h
+++ b/include/acpi/acpigen.h
@@ -73,6 +73,18 @@ enum {
RETURN_OP = 0xa4,
};

+/**
+ * enum psd_coord - Coordination types for P-states
+ *
+ * The type of coordination that exists (hardware) or is required (software) as
+ * a result of the underlying hardware dependency
+ */
+enum psd_coord {
+ SW_ALL = 0xfc,
+ SW_ANY = 0xfd,
+ HW_ALL = 0xfe
+};
+
/**
* acpigen_get_current() - Get the current ACPI code output pointer
*
--
2.28.0.526.ge36021eeef-goog