From b01ac7e26453677318776885d4ab870f59553ae6 Mon Sep 17 00:00:00 2001 From: Patrick Rudolph Date: Sun, 26 Jul 2020 14:23:37 +0200 Subject: cpu/intel/common: Fill cpu voltage in SMBIOS tables Introduce a weak function to let the platform code provide the processor voltage in 100mV units. Implement the function on Intel platforms using the MSR_PERF_STATUS msr. On other platforms the processor voltage still reads as unknown. Tested on Intel CFL. The CPU voltage is correctly advertised. Change-Id: I31a7efcbeede50d986a1c096a4a59a316e09f825 Signed-off-by: Patrick Rudolph Reviewed-on: https://review.coreboot.org/c/coreboot/+/43904 Tested-by: build bot (Jenkins) Reviewed-by: Angel Pons Reviewed-by: Jonathan Zhang Reviewed-by: Nico Huber --- src/arch/x86/smbios.c | 10 ++++++++++ src/cpu/intel/common/Kconfig | 3 +++ src/cpu/intel/common/Makefile.inc | 1 + src/cpu/intel/common/voltage.c | 12 ++++++++++++ src/cpu/intel/haswell/Kconfig | 1 + src/include/smbios.h | 1 + 6 files changed, 28 insertions(+) create mode 100644 src/cpu/intel/common/voltage.c (limited to 'src') diff --git a/src/arch/x86/smbios.c b/src/arch/x86/smbios.c index dc676cf141..da77284d37 100644 --- a/src/arch/x86/smbios.c +++ b/src/arch/x86/smbios.c @@ -493,6 +493,12 @@ unsigned int __weak smbios_cache_conf_operation_mode(u8 level) return SMBIOS_CACHE_OP_MODE_UNKNOWN; /* Unknown */ } +/* Returns the processor voltage in 100mV units */ +unsigned int __weak smbios_cpu_get_voltage(void) +{ + return 0; /* Unknown */ +} + static size_t get_number_of_caches(struct cpuid_result res_deterministic_cache) { size_t max_logical_cpus_sharing_cache = 0; @@ -595,6 +601,7 @@ static int smbios_write_type3(unsigned long *current, int handle) static int smbios_write_type4(unsigned long *current, int handle) { + unsigned int cpu_voltage; struct cpuid_result res; struct smbios_type4 *t = (struct smbios_type4 *)*current; int len = sizeof(struct smbios_type4); @@ -686,6 +693,9 @@ static int smbios_write_type4(unsigned long *current, int handle) } } t->processor_characteristics = characteristics | smbios_processor_characteristics(); + cpu_voltage = smbios_cpu_get_voltage(); + if (cpu_voltage > 0) + t->voltage = 0x80 | cpu_voltage; *current += len; return len; diff --git a/src/cpu/intel/common/Kconfig b/src/cpu/intel/common/Kconfig index 01f2721b59..7f9033cf65 100644 --- a/src/cpu/intel/common/Kconfig +++ b/src/cpu/intel/common/Kconfig @@ -32,6 +32,9 @@ config CPU_INTEL_COMMON_TIMEBASE endif +config CPU_INTEL_COMMON_VOLTAGE + bool + config CPU_INTEL_COMMON_SMM bool default y if CPU_INTEL_COMMON diff --git a/src/cpu/intel/common/Makefile.inc b/src/cpu/intel/common/Makefile.inc index 8b81a121d3..530ecee009 100644 --- a/src/cpu/intel/common/Makefile.inc +++ b/src/cpu/intel/common/Makefile.inc @@ -1,5 +1,6 @@ ramstage-$(CONFIG_CPU_INTEL_COMMON) += common_init.c ramstage-$(CONFIG_CPU_INTEL_COMMON) += hyperthreading.c +ramstage-$(CONFIG_CPU_INTEL_COMMON_VOLTAGE) += voltage.c ifeq ($(CONFIG_CPU_INTEL_COMMON_TIMEBASE),y) bootblock-y += fsb.c diff --git a/src/cpu/intel/common/voltage.c b/src/cpu/intel/common/voltage.c new file mode 100644 index 0000000000..38951a06db --- /dev/null +++ b/src/cpu/intel/common/voltage.c @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include +#include + +/* This is not an architectural MSR. */ +#define MSR_PERF_STATUS 0x198 + +unsigned int smbios_cpu_get_voltage(void) +{ + return (rdmsr(MSR_PERF_STATUS).hi & 0xffff) * 10 / 8192; +} diff --git a/src/cpu/intel/haswell/Kconfig b/src/cpu/intel/haswell/Kconfig index fbfa71456b..0d3d132006 100644 --- a/src/cpu/intel/haswell/Kconfig +++ b/src/cpu/intel/haswell/Kconfig @@ -20,6 +20,7 @@ config CPU_SPECIFIC_OPTIONS select CPU_INTEL_COMMON select CPU_INTEL_COMMON_TIMEBASE select HAVE_ASAN_IN_ROMSTAGE + select CPU_INTEL_COMMON_VOLTAGE config SMM_TSEG_SIZE hex diff --git a/src/include/smbios.h b/src/include/smbios.h index 6a19655b31..4ddf4384dc 100644 --- a/src/include/smbios.h +++ b/src/include/smbios.h @@ -40,6 +40,7 @@ const char *smbios_system_sku(void); unsigned int smbios_cpu_get_max_speed_mhz(void); unsigned int smbios_cpu_get_current_speed_mhz(void); +unsigned int smbios_cpu_get_voltage(void); const char *smbios_mainboard_manufacturer(void); const char *smbios_mainboard_product_name(void); -- cgit v1.2.3