Adds a syscall interface to represent the energy and frequency related PAPR attributes on the system using the new H_CALL "H_GET_ENERGY_SCALE_INFO".

H_GET_EM_PARMS H_CALL was previously responsible for exporting this information in the lparcfg, however the H_GET_EM_PARMS H_CALL will be deprecated P10 onwards.

The H_GET_ENERGY_SCALE_INFO H_CALL is of the following call format: hcall( uint64 H_GET_ENERGY_SCALE_INFO, // Get energy scale info uint64 flags, // Per the flag request uint64 firstAttributeId,// The attribute id uint64 bufferAddress, // Guest physical address of the output buffer uint64 bufferSize // The size in bytes of the output buffer ); As specified in PAPR+ v2.11, section 14.14.3.

This H_CALL can query either all the attributes at once with firstAttributeId = 0, flags = 0 as well as query only one attribute at a time with firstAttributeId = id, flags = 1.

The output buffer consists of the following 1. number of attributes - 8 bytes 2. array offset to the data location - 8 bytes 3. version info - 1 byte 4. A data array of size num attributes, which contains the following: a. attribute ID - 8 bytes b. attribute value in number - 8 bytes c. attribute name in string - 64 bytes d. attribute value in string - 64 bytes

The new H_CALL exports information in direct string value format, hence a new interface has been introduced in /sys/firmware/papr/energy_scale_info to export this information to userspace so that the firmware can add new values without the need for the kernel to be changed.

The H_CALL returns the name, numeric value and string value (if exists)

The format of exposing the sysfs information is as follows: /sys/firmware/papr/energy_scale_info/ |-- <id>/ |-- desc |-- value |-- value_desc (if exists) |-- <id>/ |-- desc |-- value |-- value_desc (if exists) ...

The energy information that is exported is useful for userspace tools such as powerpc-utils. Currently these tools infer the "power_mode_data" value in the lparcfg, which in turn is obtained from the to be deprecated H_GET_EM_PARMS H_CALL.

On future platforms, such userspace utilities will have to look at the data returned from the new H_CALL being populated in this new sysfs interface and report this information directly without the need of interpretation.

Signed-off-by: Pratik R. Sampat psampat@linux.ibm.com --- .../sysfs-firmware-papr-energy-scale-info | 29 ++ arch/powerpc/include/asm/firmware.h | 4 +- arch/powerpc/include/asm/hvcall.h | 3 +- arch/powerpc/kvm/trace_hv.h | 1 + arch/powerpc/platforms/pseries/Makefile | 3 +- arch/powerpc/platforms/pseries/firmware.c | 1 + .../pseries/papr_platform_attributes.c | 361 ++++++++++++++++++ 7 files changed, 399 insertions(+), 3 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info create mode 100644 arch/powerpc/platforms/pseries/papr_platform_attributes.c

diff --git a/Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info b/Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info new file mode 100644 index 000000000000..141a6b371469 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info @@ -0,0 +1,29 @@ +What: /sys/firmware/papr/energy_scale_info +Date: February 2022 +Contact: Linux for PowerPC mailing list linuxppc-dev@ozlabs.org +Description: Directory hosting a set of platform attributes like + energy/frequency on Linux running as a PAPR guest. + + Each file in a directory contains a platform + attribute hierarchy pertaining to performance/ + energy-savings mode and processor frequency. + +What: /sys/firmware/papr/energy_scale_info/<id> +Date: February 2022 +Contact: Linux for PowerPC mailing list linuxppc-dev@ozlabs.org +Description: Energy, frequency attributes directory for POWERVM servers + +What: /sys/firmware/papr/energy_scale_info/<id>/desc +Date: February 2022 +Contact: Linux for PowerPC mailing list linuxppc-dev@ozlabs.org +Description: String description of the energy attribute of <id> + +What: /sys/firmware/papr/energy_scale_info/<id>/value +Date: February 2022 +Contact: Linux for PowerPC mailing list linuxppc-dev@ozlabs.org +Description: Numeric value of the energy attribute of <id> + +What: /sys/firmware/papr/energy_scale_info/<id>/value_desc +Date: February 2022 +Contact: Linux for PowerPC mailing list linuxppc-dev@ozlabs.org +Description: String value of the energy attribute of <id> diff --git a/arch/powerpc/include/asm/firmware.h b/arch/powerpc/include/asm/firmware.h index 9b702d2b80fb..8dddd34b8ecf 100644 --- a/arch/powerpc/include/asm/firmware.h +++ b/arch/powerpc/include/asm/firmware.h @@ -54,6 +54,7 @@ #define FW_FEATURE_STUFF_TCE ASM_CONST(0x0000008000000000) #define FW_FEATURE_RPT_INVALIDATE ASM_CONST(0x0000010000000000) #define FW_FEATURE_FORM2_AFFINITY ASM_CONST(0x0000020000000000) +#define FW_FEATURE_ENERGY_SCALE_INFO ASM_CONST(0x0000040000000000)

#ifndef __ASSEMBLY__

@@ -74,7 +75,8 @@ enum { FW_FEATURE_HPT_RESIZE | FW_FEATURE_DRMEM_V2 | FW_FEATURE_DRC_INFO | FW_FEATURE_BLOCK_REMOVE | FW_FEATURE_PAPR_SCM | FW_FEATURE_ULTRAVISOR | - FW_FEATURE_RPT_INVALIDATE | FW_FEATURE_FORM2_AFFINITY, + FW_FEATURE_RPT_INVALIDATE | FW_FEATURE_FORM2_AFFINITY | + FW_FEATURE_ENERGY_SCALE_INFO, FW_FEATURE_PSERIES_ALWAYS = 0, FW_FEATURE_POWERNV_POSSIBLE = FW_FEATURE_OPAL | FW_FEATURE_ULTRAVISOR, FW_FEATURE_POWERNV_ALWAYS = 0, diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index 9bcf345cb208..48f510ba9f4a 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -323,7 +323,8 @@ #define H_SCM_PERFORMANCE_STATS 0x418 #define H_RPT_INVALIDATE 0x448 #define H_SCM_FLUSH 0x44C -#define MAX_HCALL_OPCODE H_SCM_FLUSH +#define H_GET_ENERGY_SCALE_INFO 0x450 +#define MAX_HCALL_OPCODE H_GET_ENERGY_SCALE_INFO

/* Scope args for H_SCM_UNBIND_ALL */ #define H_UNBIND_SCOPE_ALL (0x1) diff --git a/arch/powerpc/kvm/trace_hv.h b/arch/powerpc/kvm/trace_hv.h index 830a126e095d..38cd0ed0a617 100644 --- a/arch/powerpc/kvm/trace_hv.h +++ b/arch/powerpc/kvm/trace_hv.h @@ -115,6 +115,7 @@ {H_VASI_STATE, "H_VASI_STATE"}, \ {H_ENABLE_CRQ, "H_ENABLE_CRQ"}, \ {H_GET_EM_PARMS, "H_GET_EM_PARMS"}, \ + {H_GET_ENERGY_SCALE_INFO, "H_GET_ENERGY_SCALE_INFO"}, \ {H_SET_MPP, "H_SET_MPP"}, \ {H_GET_MPP, "H_GET_MPP"}, \ {H_HOME_NODE_ASSOCIATIVITY, "H_HOME_NODE_ASSOCIATIVITY"}, \ diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile index ee60b59024b4..0489f84a609a 100644 --- a/arch/powerpc/platforms/pseries/Makefile +++ b/arch/powerpc/platforms/pseries/Makefile @@ -6,7 +6,8 @@ obj-y := lpar.o hvCall.o nvram.o reconfig.o \ of_helpers.o \ setup.o iommu.o event_sources.o ras.o \ firmware.o power.o dlpar.o mobility.o rng.o \ - pci.o pci_dlpar.o eeh_pseries.o msi.o + pci.o pci_dlpar.o eeh_pseries.o msi.o \ + papr_platform_attributes.o obj-$(CONFIG_SMP) += smp.o obj-$(CONFIG_KEXEC_CORE) += kexec.o obj-$(CONFIG_PSERIES_ENERGY) += pseries_energy.o diff --git a/arch/powerpc/platforms/pseries/firmware.c b/arch/powerpc/platforms/pseries/firmware.c index f162156b7b68..09c119b2f623 100644 --- a/arch/powerpc/platforms/pseries/firmware.c +++ b/arch/powerpc/platforms/pseries/firmware.c @@ -66,6 +66,7 @@ hypertas_fw_features_table[] = { {FW_FEATURE_BLOCK_REMOVE, "hcall-block-remove"}, {FW_FEATURE_PAPR_SCM, "hcall-scm"}, {FW_FEATURE_RPT_INVALIDATE, "hcall-rpt-invalidate"}, + {FW_FEATURE_ENERGY_SCALE_INFO, "hcall-energy-scale-info"}, };

/* Build up the firmware features bitmask using the contents of diff --git a/arch/powerpc/platforms/pseries/papr_platform_attributes.c b/arch/powerpc/platforms/pseries/papr_platform_attributes.c new file mode 100644 index 000000000000..515150417bb3 --- /dev/null +++ b/arch/powerpc/platforms/pseries/papr_platform_attributes.c @@ -0,0 +1,361 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Platform energy and frequency attributes driver + * + * This driver creates a sys file at /sys/firmware/papr/ which encapsulates a + * directory structure containing files in keyword - value pairs that specify + * energy and frequency configuration of the system. + * + * The format of exposing the sysfs information is as follows: + * /sys/firmware/papr/energy_scale_info/ + * |-- <id>/ + * |-- desc + * |-- value + * |-- value_desc (if exists) + * |-- <id>/ + * |-- desc + * |-- value + * |-- value_desc (if exists) + * + * Copyright 2022 IBM Corp. + */ + +#include <asm/hvcall.h> +#include <asm/machdep.h> + +#include "pseries.h" + +/* + * Flag attributes to fetch either all or one attribute from the HCALL + * flag = BE(0) => fetch all attributes with firstAttributeId = 0 + * flag = BE(1) => fetch a single attribute with firstAttributeId = id + */ +#define ESI_FLAGS_ALL 0 +#define ESI_FLAGS_SINGLE (1ull << 63) + +#define KOBJ_MAX_ATTRS 3 + +#define ESI_HDR_SIZE sizeof(struct h_energy_scale_info_hdr) +#define ESI_ATTR_SIZE sizeof(struct energy_scale_attribute) +#define CURR_MAX_ESI_ATTRS 8 + +struct energy_scale_attribute { + __be64 id; + __be64 val; + u8 desc[64]; + u8 value_desc[64]; +} __packed; + +struct h_energy_scale_info_hdr { + __be64 num_attrs; + __be64 array_offset; + u8 data_header_version; +} __packed; + +struct papr_attr { + u64 id; + struct kobj_attribute kobj_attr; +}; + +struct papr_group { + struct attribute_group pg; + struct papr_attr pgattrs[KOBJ_MAX_ATTRS]; +}; + +static struct papr_group *papr_groups; +/* /sys/firmware/papr */ +static struct kobject *papr_kobj; +/* /sys/firmware/papr/energy_scale_info */ +static struct kobject *esi_kobj; + +/* + * Energy modes can change dynamically hence making a new hcall each time the + * information needs to be retrieved + */ +static int papr_get_attr(u64 id, struct energy_scale_attribute *esi) +{ + int esi_buf_size = ESI_HDR_SIZE + (CURR_MAX_ESI_ATTRS * ESI_ATTR_SIZE); + int ret, max_esi_attrs = CURR_MAX_ESI_ATTRS; + struct energy_scale_attribute *curr_esi; + struct h_energy_scale_info_hdr *hdr; + char *buf; + + buf = kmalloc(esi_buf_size, GFP_KERNEL); + if (buf == NULL) + return -ENOMEM; + +retry: + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE, + id, virt_to_phys(buf), + esi_buf_size); + + /* + * If the hcall fails with not enough memory for either the + * header or data, attempt to allocate more + */ + if (ret == H_PARTIAL || ret == H_P4) { + char *temp_buf; + + max_esi_attrs += 4; + esi_buf_size = ESI_HDR_SIZE + (CURR_MAX_ESI_ATTRS * max_esi_attrs); + + temp_buf = krealloc(buf, esi_buf_size, GFP_KERNEL); + if (temp_buf) + buf = temp_buf; + else + return -ENOMEM; + + goto retry; + } + + if (ret != H_SUCCESS) { + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO"); + ret = -EIO; + goto out_buf; + } + + hdr = (struct h_energy_scale_info_hdr *) buf; + curr_esi = (struct energy_scale_attribute *) + (buf + be64_to_cpu(hdr->array_offset)); + + if (esi_buf_size < + be64_to_cpu(hdr->array_offset) + (be64_to_cpu(hdr->num_attrs) + * sizeof(struct energy_scale_attribute))) { + ret = -EIO; + goto out_buf; + } + + *esi = *curr_esi; + +out_buf: + kfree(buf); + + return ret; +} + +/* + * Extract and export the description of the energy scale attributes + */ +static ssize_t desc_show(struct kobject *kobj, + struct kobj_attribute *kobj_attr, + char *buf) +{ + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr, + kobj_attr); + struct energy_scale_attribute esi; + int ret; + + ret = papr_get_attr(pattr->id, &esi); + if (ret) + return ret; + + return sysfs_emit(buf, "%s\n", esi.desc); +} + +/* + * Extract and export the numeric value of the energy scale attributes + */ +static ssize_t val_show(struct kobject *kobj, + struct kobj_attribute *kobj_attr, + char *buf) +{ + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr, + kobj_attr); + struct energy_scale_attribute esi; + int ret; + + ret = papr_get_attr(pattr->id, &esi); + if (ret) + return ret; + + return sysfs_emit(buf, "%llu\n", be64_to_cpu(esi.val)); +} + +/* + * Extract and export the value description in string format of the energy + * scale attributes + */ +static ssize_t val_desc_show(struct kobject *kobj, + struct kobj_attribute *kobj_attr, + char *buf) +{ + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr, + kobj_attr); + struct energy_scale_attribute esi; + int ret; + + ret = papr_get_attr(pattr->id, &esi); + if (ret) + return ret; + + return sysfs_emit(buf, "%s\n", esi.value_desc); +} + +static struct papr_ops_info { + const char *attr_name; + ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *kobj_attr, + char *buf); +} ops_info[KOBJ_MAX_ATTRS] = { + { "desc", desc_show }, + { "value", val_show }, + { "value_desc", val_desc_show }, +}; + +static void add_attr(u64 id, int index, struct papr_attr *attr) +{ + attr->id = id; + sysfs_attr_init(&attr->kobj_attr.attr); + attr->kobj_attr.attr.name = ops_info[index].attr_name; + attr->kobj_attr.attr.mode = 0444; + attr->kobj_attr.show = ops_info[index].show; +} + +static int add_attr_group(u64 id, struct papr_group *pg, bool show_val_desc) +{ + int i; + + for (i = 0; i < KOBJ_MAX_ATTRS; i++) { + if (!strcmp(ops_info[i].attr_name, "value_desc") && + !show_val_desc) { + continue; + } + add_attr(id, i, &pg->pgattrs[i]); + pg->pg.attrs[i] = &pg->pgattrs[i].kobj_attr.attr; + } + + return sysfs_create_group(esi_kobj, &pg->pg); +} + + +static int __init papr_init(void) +{ + int esi_buf_size = ESI_HDR_SIZE + (CURR_MAX_ESI_ATTRS * ESI_ATTR_SIZE); + int ret, idx, i, max_esi_attrs = CURR_MAX_ESI_ATTRS; + struct h_energy_scale_info_hdr *esi_hdr; + struct energy_scale_attribute *esi_attrs; + uint64_t num_attrs; + char *esi_buf; + + if (!firmware_has_feature(FW_FEATURE_LPAR) || + !firmware_has_feature(FW_FEATURE_ENERGY_SCALE_INFO)) { + return -ENXIO; + } + + esi_buf = kmalloc(esi_buf_size, GFP_KERNEL); + if (esi_buf == NULL) + return -ENOMEM; + /* + * hcall( + * uint64 H_GET_ENERGY_SCALE_INFO, // Get energy scale info + * uint64 flags, // Per the flag request + * uint64 firstAttributeId, // The attribute id + * uint64 bufferAddress, // Guest physical address of the output buffer + * uint64 bufferSize); // The size in bytes of the output buffer + */ +retry: + + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_ALL, 0, + virt_to_phys(esi_buf), esi_buf_size); + + /* + * If the hcall fails with not enough memory for either the + * header or data, attempt to allocate more + */ + if (ret == H_PARTIAL || ret == H_P4) { + char *temp_esi_buf; + + max_esi_attrs += 4; + esi_buf_size = ESI_HDR_SIZE + (CURR_MAX_ESI_ATTRS * max_esi_attrs); + + temp_esi_buf = krealloc(esi_buf, esi_buf_size, GFP_KERNEL); + if (temp_esi_buf) + esi_buf = temp_esi_buf; + else + return -ENOMEM; + + goto retry; + } + + if (ret != H_SUCCESS) { + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO, ret: %d\n", ret); + goto out_free_esi_buf; + } + + esi_hdr = (struct h_energy_scale_info_hdr *) esi_buf; + num_attrs = be64_to_cpu(esi_hdr->num_attrs); + esi_attrs = (struct energy_scale_attribute *) + (esi_buf + be64_to_cpu(esi_hdr->array_offset)); + + if (esi_buf_size < + be64_to_cpu(esi_hdr->array_offset) + + (num_attrs * sizeof(struct energy_scale_attribute))) { + goto out_free_esi_buf; + } + + papr_groups = kcalloc(num_attrs, sizeof(*papr_groups), GFP_KERNEL); + if (!papr_groups) + goto out_free_esi_buf; + + papr_kobj = kobject_create_and_add("papr", firmware_kobj); + if (!papr_kobj) { + pr_warn("kobject_create_and_add papr failed\n"); + goto out_papr_groups; + } + + esi_kobj = kobject_create_and_add("energy_scale_info", papr_kobj); + if (!esi_kobj) { + pr_warn("kobject_create_and_add energy_scale_info failed\n"); + goto out_kobj; + } + + /* Allocate the groups before registering */ + for (idx = 0; idx < num_attrs; idx++) { + papr_groups[idx].pg.attrs = kcalloc(KOBJ_MAX_ATTRS + 1, + sizeof(*papr_groups[idx].pg.attrs), + GFP_KERNEL); + if (!papr_groups[idx].pg.attrs) + goto out_pgattrs; + + papr_groups[idx].pg.name = kasprintf(GFP_KERNEL, "%lld", + be64_to_cpu(esi_attrs[idx].id)); + if (papr_groups[idx].pg.name == NULL) + goto out_pgattrs; + } + + for (idx = 0; idx < num_attrs; idx++) { + bool show_val_desc = true; + + /* Do not add the value desc attr if it does not exist */ + if (strnlen(esi_attrs[idx].value_desc, + sizeof(esi_attrs[idx].value_desc)) == 0) + show_val_desc = false; + + if (add_attr_group(be64_to_cpu(esi_attrs[idx].id), + &papr_groups[idx], + show_val_desc)) { + pr_warn("Failed to create papr attribute group %s\n", + papr_groups[idx].pg.name); + idx = num_attrs; + goto out_pgattrs; + } + } + + kfree(esi_buf); + return 0; +out_pgattrs: + for (i = 0; i < idx ; i++) { + kfree(papr_groups[i].pg.attrs); + kfree(papr_groups[i].pg.name); + } + kobject_put(esi_kobj); +out_kobj: + kobject_put(papr_kobj); +out_papr_groups: + kfree(papr_groups); +out_free_esi_buf: + kfree(esi_buf); + + return -ENOMEM; +} + +machine_device_initcall(pseries, papr_init);