| Message ID | 20211220151438.1196-4-ricardo.neri-calderon@linux.intel.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Thermal: Introduce the Hardware Feedback Interface for thermal and performance management | expand |
On Mon, Dec 20, 2021 at 4:23 PM Ricardo Neri <ricardo.neri-calderon@linux.intel.com> wrote: > > The Intel Hardware Feedback Interface provides guidance to the operating > system about the performance and energy efficiency capabilities of each > CPU in the system. Capabilities are numbers between 0 and 255 where a > higher number represents a higher capability. For each CPU, energy > efficiency and performance are reported as separate capabilities. > > Hardware computes these capabilities based on the operating conditions of > the system such as power and thermal limits. These capabilities are shared > with the operating system in a table resident in memory. Each package in > the system has its own HFI instance. Every logical CPU in the package is > represented in the table. More than one logical CPUs may be represented in > a single table entry. When the hardware updates the table, it generates a > package-level thermal interrupt. > > The size and format of the HFI table depend on the supported features and > can only be determined at runtime. To minimally initialize the HFI, parse > its features and allocate one instance per package of a data structure with > the necessary parameters to read and navigate a local copy (i.e., owned by > the driver) of individual HFI tables. > > A subsequent changeset will provide per-CPU initialization and interrupt > handling. > > Cc: Andi Kleen <ak@linux.intel.com> > Cc: Aubrey Li <aubrey.li@linux.intel.com> > Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> > Cc: Tim Chen <tim.c.chen@linux.intel.com> > Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> > Reviewed-by: Len Brown <len.brown@intel.com> > Co-developed by: Aubrey Li <aubrey.li@linux.intel.com> > Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com> > Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> > --- > Changes since v1: > * Renamed X86_FEATURE_INTEL_HFI as X86_FEATURE_HFI. (Boris) > * Reworked parsing of HFI features using bitfields instead of bitmasks. > (PeterZ). > * Removed hfi_instance::parsed as hfi_parse_features() is called only > once via intel_hfi_init() via thermal_throttle_init_device(). > (Rafael) > * Converted pr_err() to pr_debug(). (Srinivas, Rafael) > * Removed unnecessary dependency on CONFIG_SCHED_MC. > * Renamed hfi_instance::ts_counter as hfi_instance::timestamp. > * Renamed hfi_instance::table_base as hfi_instance::local_table and > relocated its definition to this patch. > * Wrapped hfi_instance::timestamp and hfi_instance:local_table in an > anonymous union, since both point at the same location. > --- > drivers/thermal/intel/Kconfig | 12 ++ > drivers/thermal/intel/Makefile | 1 + > drivers/thermal/intel/intel_hfi.c | 175 ++++++++++++++++++++++++++++ > drivers/thermal/intel/intel_hfi.h | 11 ++ > drivers/thermal/intel/therm_throt.c | 3 + > 5 files changed, 202 insertions(+) > create mode 100644 drivers/thermal/intel/intel_hfi.c > create mode 100644 drivers/thermal/intel/intel_hfi.h > > diff --git a/drivers/thermal/intel/Kconfig b/drivers/thermal/intel/Kconfig > index c83ea5d04a1d..1a21ff60fdc7 100644 > --- a/drivers/thermal/intel/Kconfig > +++ b/drivers/thermal/intel/Kconfig > @@ -99,3 +99,15 @@ config INTEL_MENLOW > Intel Menlow platform. > > If unsure, say N. > + > +config INTEL_HFI This looks like it may be too general, because HFI is not a thermal-only thing. Maybe cal it INTEL_HFI_THERMAL?
On Thu, Dec 30, 2021 at 07:43:22PM +0100, Rafael J. Wysocki wrote: > On Mon, Dec 20, 2021 at 4:23 PM Ricardo Neri > <ricardo.neri-calderon@linux.intel.com> wrote: > > > > The Intel Hardware Feedback Interface provides guidance to the operating > > system about the performance and energy efficiency capabilities of each > > CPU in the system. Capabilities are numbers between 0 and 255 where a > > higher number represents a higher capability. For each CPU, energy > > efficiency and performance are reported as separate capabilities. > > > > Hardware computes these capabilities based on the operating conditions of > > the system such as power and thermal limits. These capabilities are shared > > with the operating system in a table resident in memory. Each package in > > the system has its own HFI instance. Every logical CPU in the package is > > represented in the table. More than one logical CPUs may be represented in > > a single table entry. When the hardware updates the table, it generates a > > package-level thermal interrupt. > > > > The size and format of the HFI table depend on the supported features and > > can only be determined at runtime. To minimally initialize the HFI, parse > > its features and allocate one instance per package of a data structure with > > the necessary parameters to read and navigate a local copy (i.e., owned by > > the driver) of individual HFI tables. > > > > A subsequent changeset will provide per-CPU initialization and interrupt > > handling. > > > > Cc: Andi Kleen <ak@linux.intel.com> > > Cc: Aubrey Li <aubrey.li@linux.intel.com> > > Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> > > Cc: Tim Chen <tim.c.chen@linux.intel.com> > > Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> > > Reviewed-by: Len Brown <len.brown@intel.com> > > Co-developed by: Aubrey Li <aubrey.li@linux.intel.com> > > Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com> > > Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> > > --- > > Changes since v1: > > * Renamed X86_FEATURE_INTEL_HFI as X86_FEATURE_HFI. (Boris) > > * Reworked parsing of HFI features using bitfields instead of bitmasks. > > (PeterZ). > > * Removed hfi_instance::parsed as hfi_parse_features() is called only > > once via intel_hfi_init() via thermal_throttle_init_device(). > > (Rafael) > > * Converted pr_err() to pr_debug(). (Srinivas, Rafael) > > * Removed unnecessary dependency on CONFIG_SCHED_MC. > > * Renamed hfi_instance::ts_counter as hfi_instance::timestamp. > > * Renamed hfi_instance::table_base as hfi_instance::local_table and > > relocated its definition to this patch. > > * Wrapped hfi_instance::timestamp and hfi_instance:local_table in an > > anonymous union, since both point at the same location. > > --- > > drivers/thermal/intel/Kconfig | 12 ++ > > drivers/thermal/intel/Makefile | 1 + > > drivers/thermal/intel/intel_hfi.c | 175 ++++++++++++++++++++++++++++ > > drivers/thermal/intel/intel_hfi.h | 11 ++ > > drivers/thermal/intel/therm_throt.c | 3 + > > 5 files changed, 202 insertions(+) > > create mode 100644 drivers/thermal/intel/intel_hfi.c > > create mode 100644 drivers/thermal/intel/intel_hfi.h > > > > diff --git a/drivers/thermal/intel/Kconfig b/drivers/thermal/intel/Kconfig > > index c83ea5d04a1d..1a21ff60fdc7 100644 > > --- a/drivers/thermal/intel/Kconfig > > +++ b/drivers/thermal/intel/Kconfig > > @@ -99,3 +99,15 @@ config INTEL_MENLOW > > Intel Menlow platform. > > > > If unsure, say N. > > + > > +config INTEL_HFI > > This looks like it may be too general, because HFI is not a thermal-only thing. > > Maybe cal it INTEL_HFI_THERMAL? True. The *Enhanced* HFI introduces the concept of thread classes [1]. I was planning to wrap this patchset, which parses the HFI table and deals with updates, as INTEL_HFI. The code that deals with classes would be wrapped as INTEL_EHFI. After this comment, so you still think that INTEL_HFI_THERMAL makes more sense? Thanks and BR, Ricardo [1]. https://www.intel.com/content/www/us/en/develop/download/intel-architecture-instruction-set-extensions-programming-reference.html , Chapter 13
On Sun, 2022-01-02 at 13:46 -0800, Ricardo Neri wrote: > On Thu, Dec 30, 2021 at 07:43:22PM +0100, Rafael J. Wysocki wrote: > > On Mon, Dec 20, 2021 at 4:23 PM Ricardo Neri > > <ricardo.neri-calderon@linux.intel.com> wrote: > > > > [...] > > This looks like it may be too general, because HFI is not a > > thermal-only thing. > > > > > Maybe cal it INTEL_HFI_THERMAL? > > True. The *Enhanced* HFI introduces the concept of thread classes > [1]. I was > planning to wrap this patchset, which parses the HFI table and deals > with updates, as INTEL_HFI. The code that deals with classes would be > wrapped as INTEL_EHFI. > > After this comment, so you still think that INTEL_HFI_THERMAL makes > more > sense? In general most of the configs for Intel thermal is has THERMAL suffix, so to be consistent may be add THERMAL also at the end. You can still add INTEL_EHFI as a silent config, which user will not select. It will be selected by default with INTEL_HFI_THERMAL. Thanks, Srinivas > > Thanks and BR, > Ricardo > > > [1]. > https://www.intel.com/content/www/us/en/develop/download/intel-architecture-instruction-set-extensions-programming-reference.html > , Chapter 13 >
On Sun, Jan 02, 2022 at 06:22:33PM -0800, srinivas pandruvada wrote: > On Sun, 2022-01-02 at 13:46 -0800, Ricardo Neri wrote: > > On Thu, Dec 30, 2021 at 07:43:22PM +0100, Rafael J. Wysocki wrote: > > > On Mon, Dec 20, 2021 at 4:23 PM Ricardo Neri > > > <ricardo.neri-calderon@linux.intel.com> wrote: > > > > > > > [...] > > > > This looks like it may be too general, because HFI is not a > > > thermal-only thing. > > > > > > > > Maybe cal it INTEL_HFI_THERMAL? > > > > True. The *Enhanced* HFI introduces the concept of thread classes > > [1]. I was > > planning to wrap this patchset, which parses the HFI table and deals > > with updates, as INTEL_HFI. The code that deals with classes would be > > wrapped as INTEL_EHFI. > > > > After this comment, so you still think that INTEL_HFI_THERMAL makes > > more > > sense? > In general most of the configs for Intel thermal is has THERMAL suffix, > so to be consistent may be add THERMAL also at the end. > > You can still add INTEL_EHFI as a silent config, which user will not > select. It will be selected by default with INTEL_HFI_THERMAL. That makes sense to me. I will add the _THERMAL suffix to the config option. Thanks and BR, Ricardo
diff --git a/drivers/thermal/intel/Kconfig b/drivers/thermal/intel/Kconfig index c83ea5d04a1d..1a21ff60fdc7 100644 --- a/drivers/thermal/intel/Kconfig +++ b/drivers/thermal/intel/Kconfig @@ -99,3 +99,15 @@ config INTEL_MENLOW Intel Menlow platform. If unsure, say N. + +config INTEL_HFI + bool "Intel Hardware Feedback Interface" + depends on CPU_SUP_INTEL + depends on X86_THERMAL_VECTOR + help + Select this option to enable the Hardware Feedback Interface. If + selected, hardware provides guidance to the operating system on + the performance and energy efficiency capabilities of each CPU. + These capabilities may change as a result of changes in the operating + conditions of the system such power and thermal limits. If selected, + the kernel relays updates in CPUs' capabilities to userspace. diff --git a/drivers/thermal/intel/Makefile b/drivers/thermal/intel/Makefile index 960b56268b4a..1a80bffcd699 100644 --- a/drivers/thermal/intel/Makefile +++ b/drivers/thermal/intel/Makefile @@ -13,3 +13,4 @@ obj-$(CONFIG_INTEL_PCH_THERMAL) += intel_pch_thermal.o obj-$(CONFIG_INTEL_TCC_COOLING) += intel_tcc_cooling.o obj-$(CONFIG_X86_THERMAL_VECTOR) += therm_throt.o obj-$(CONFIG_INTEL_MENLOW) += intel_menlow.o +obj-$(CONFIG_INTEL_HFI) += intel_hfi.o diff --git a/drivers/thermal/intel/intel_hfi.c b/drivers/thermal/intel/intel_hfi.c new file mode 100644 index 000000000000..375d835cc5e3 --- /dev/null +++ b/drivers/thermal/intel/intel_hfi.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Hardware Feedback Interface Driver + * + * Copyright (c) 2021, Intel Corporation. + * + * Authors: Aubrey Li <aubrey.li@linux.intel.com> + * Ricardo Neri <ricardo.neri-calderon@linux.intel.com> + * + * + * The Hardware Feedback Interface provides a performance and energy efficiency + * capability information for each CPU in the system. Depending on the processor + * model, hardware may periodically update these capabilities as a result of + * changes in the operating conditions (e.g., power limits or thermal + * constraints). On other processor models, there is a single HFI update + * at boot. + * + * This file provides functionality to process HFI updates and relay these + * updates to userspace. + */ + +#define pr_fmt(fmt) "intel-hfi: " fmt + +#include <linux/slab.h> + +#include "intel_hfi.h" + +/* CPUID detection and enumeration definitions for HFI */ + +#define CPUID_HFI_LEAF 6 + +union hfi_capabilities { + struct { + u8 performance:1; + u8 energy_efficiency:1; + u8 __reserved:6; + } split; + u8 bits; +}; + +union cpuid6_edx { + struct { + union hfi_capabilities capabilities; + u32 table_pages:4; + u32 __reserved:4; + s32 index:16; + } split; + u32 full; +}; + +/** + * struct hfi_cpu_data - HFI capabilities per CPU + * @perf_cap: Performance capability + * @ee_cap: Energy efficiency capability + * + * Capabilities of a logical processor in the HFI table. These capabilities are + * unitless. + */ +struct hfi_cpu_data { + u8 perf_cap; + u8 ee_cap; +} __packed; + +/** + * struct hfi_hdr - Header of the HFI table + * @perf_updated: Hardware updated performance capabilities + * @ee_updated: Hardware updated energy efficiency capabilities + * + * Properties of the data in an HFI table. + */ +struct hfi_hdr { + u8 perf_updated; + u8 ee_updated; +} __packed; + +/** + * struct hfi_instance - Representation of an HFI instance (i.e., a table) + * @local_table: Base of the local copy of the HFI table + * @timestamp: Timestamp of the last update of the local table. + * Located at the base of the local table. + * @hdr: Base address of the local table header + * @data: Base address of the local table data + * + * A set of parameters to parse and navigate a specific HFI table. + */ +struct hfi_instance { + union { + void *local_table; + u64 *timestamp; + }; + void *hdr; + void *data; +}; + +/** + * struct hfi_features - Supported HFI features + * @nr_table_pages: Size of the HFI table in 4KB pages + * @cpu_stride: Stride size to locate capability data of a logical + * processor within the table (i.e., row stride) + * @hdr_size: Size of table header + * + * Parameters and supported features that are common to all HFI instances + */ +struct hfi_features { + unsigned int nr_table_pages; + unsigned int cpu_stride; + unsigned int hdr_size; +}; + +static int max_hfi_instances; +static struct hfi_instance *hfi_instances; + +static struct hfi_features hfi_features; + +static __init int hfi_parse_features(void) +{ + unsigned int nr_capabilities; + union cpuid6_edx edx; + + if (!boot_cpu_has(X86_FEATURE_HFI)) + return -ENODEV; + + /* + * If we are here we know that CPUID_HFI_LEAF exists. Parse the + * supported capabilities and the size of the HFI table. + */ + edx.full = cpuid_edx(CPUID_HFI_LEAF); + + if (!edx.split.capabilities.split.performance) { + pr_debug("Performance reporting not supported! Not using HFI\n"); + return -ENODEV; + } + + /* + * The number of supported capabilities determines the number of + * columns in the HFI table. Exclude reserved bits. + */ + edx.split.capabilities.split.__reserved = 0; + nr_capabilities = hweight8(edx.split.capabilities.bits); + + /* The number of 4KB pages required by the table */ + hfi_features.nr_table_pages = edx.split.table_pages + 1; + + /* + * The header contains change indications for each supported feature. + * The size of the table header is rounded up to be a multiple of 8 + * bytes. + */ + hfi_features.hdr_size = DIV_ROUND_UP(nr_capabilities, 8) * 8; + + /* + * Data of each logical processor is also rounded up to be a multiple + * of 8 bytes. + */ + hfi_features.cpu_stride = DIV_ROUND_UP(nr_capabilities, 8) * 8; + + return 0; +} + +void __init intel_hfi_init(void) +{ + if (hfi_parse_features()) + return; + + /* There is one HFI instance per die/package. */ + max_hfi_instances = topology_max_packages() * + topology_max_die_per_package(); + + /* + * This allocation may fail. CPU hotplug callbacks must check + * for a null pointer. + */ + hfi_instances = kcalloc(max_hfi_instances, sizeof(*hfi_instances), + GFP_KERNEL); +} diff --git a/drivers/thermal/intel/intel_hfi.h b/drivers/thermal/intel/intel_hfi.h new file mode 100644 index 000000000000..8fa3f7c0a64b --- /dev/null +++ b/drivers/thermal/intel/intel_hfi.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _INTEL_HFI_H +#define _INTEL_HFI_H + +#if defined(CONFIG_INTEL_HFI) +void __init intel_hfi_init(void); +#else +static inline void intel_hfi_init(void) { } +#endif + +#endif /* _INTEL_HFI_H */ diff --git a/drivers/thermal/intel/therm_throt.c b/drivers/thermal/intel/therm_throt.c index dab7e8fb1059..ac408714d52b 100644 --- a/drivers/thermal/intel/therm_throt.c +++ b/drivers/thermal/intel/therm_throt.c @@ -32,6 +32,7 @@ #include <asm/irq.h> #include <asm/msr.h> +#include "intel_hfi.h" #include "thermal_interrupt.h" /* How long to wait between reporting thermal events */ @@ -509,6 +510,8 @@ static __init int thermal_throttle_init_device(void) if (!atomic_read(&therm_throt_en)) return 0; + intel_hfi_init(); + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/therm:online", thermal_throttle_online, thermal_throttle_offline);