Adds a generic 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 ); 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 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 in an extensible pass-through format. 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 <psam...@linux.ibm.com> --- .../sysfs-firmware-papr-energy-scale-info | 26 ++ arch/powerpc/include/asm/hvcall.h | 21 +- arch/powerpc/kvm/trace_hv.h | 1 + arch/powerpc/platforms/pseries/Makefile | 3 +- .../pseries/papr_platform_attributes.c | 292 ++++++++++++++++++ 5 files changed, 341 insertions(+), 2 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..499bc1ae173a --- /dev/null +++ b/Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info @@ -0,0 +1,26 @@ +What: /sys/firmware/papr/energy_scale_info +Date: June 2021 +Contact: Linux for PowerPC mailing list <linuxppc-...@ozlabs.org> +Description: Director hosting a set of platform attributes 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> + /sys/firmware/papr/energy_scale_info/<id>/desc + /sys/firmware/papr/energy_scale_info/<id>/value + /sys/firmware/papr/energy_scale_info/<id>/value_desc +Date: June 2021 +Contact: Linux for PowerPC mailing list <linuxppc-...@ozlabs.org> +Description: PAPR attributes directory for POWERVM servers + + This directory provides PAPR information. It + contains below sysfs attributes: + + - desc: File contains the name of attribute <id> + + - value: Numeric value of attribute <id> + + - value_desc: String value of attribute <id> diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index e3b29eda8074..19a2a8c77a49 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -316,7 +316,8 @@ #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) @@ -631,6 +632,24 @@ struct hv_gpci_request_buffer { uint8_t bytes[HGPCI_MAX_DATA_BYTES]; } __packed; +#define MAX_EM_ATTRS 10 +#define MAX_EM_DATA_BYTES \ + (sizeof(struct energy_scale_attributes) * MAX_EM_ATTRS) +struct energy_scale_attributes { + __be64 attr_id; + __be64 attr_value; + unsigned char attr_desc[64]; + unsigned char attr_value_desc[64]; +} __packed; + +struct hv_energy_scale_buffer { + __be64 num_attr; + __be64 array_offset; + __u8 data_header_version; + unsigned char data[MAX_EM_DATA_BYTES]; +} __packed; + + #endif /* __ASSEMBLY__ */ #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_HVCALL_H */ 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 c8a2b0b05ac0..d14fca89ac25 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_SCANLOG) += scanlog.o obj-$(CONFIG_KEXEC_CORE) += kexec.o 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..498c74a5e9ab --- /dev/null +++ b/arch/powerpc/platforms/pseries/papr_platform_attributes.c @@ -0,0 +1,292 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * PAPR platform energy attributes driver + * + * This driver creates a sys file at /sys/firmware/papr/ which contains + * files keyword - value pairs that specify energy configuration of the system. + * + * Copyright 2021 IBM Corp. + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/hugetlb.h> +#include <asm/lppaca.h> +#include <asm/hvcall.h> +#include <asm/firmware.h> +#include <asm/time.h> +#include <asm/prom.h> +#include <asm/vdso_datapage.h> +#include <asm/vio.h> +#include <asm/mmu.h> +#include <asm/machdep.h> +#include <asm/drmem.h> + +#include "pseries.h" + +#define MAX_ATTRS 3 +#define MAX_NAME_LEN 16 + +struct papr_attr { + u64 id; + struct kobj_attribute attr; +}; +struct papr_group { + char name[MAX_NAME_LEN]; + struct attribute_group pg; + struct papr_attr *pgattrs; +} *pgs; + +struct kobject *papr_kobj; +struct kobject *escale_kobj; +struct hv_energy_scale_buffer *em_buf; +struct energy_scale_attributes *ea; + +static ssize_t papr_show_desc(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + struct papr_attr *pattr = container_of(attr, struct papr_attr, attr); + int idx, ret = 0; + + /* + * We do not expect the name to change, hence use the old value + * and save a HCALL + */ + for (idx = 0; idx < be64_to_cpu(em_buf->num_attr); idx++) { + if (pattr->id == be64_to_cpu(ea[idx].attr_id)) { + ret = sprintf(buf, "%s\n", ea[idx].attr_desc); + if (ret < 0) + ret = -EIO; + break; + } + } + + return ret; +} + +static ssize_t papr_show_value(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + struct papr_attr *pattr = container_of(attr, struct papr_attr, attr); + struct hv_energy_scale_buffer *t_buf; + struct energy_scale_attributes *t_ea; + int data_offset, ret = 0; + + t_buf = kmalloc(sizeof(*t_buf), GFP_KERNEL); + if (t_buf == NULL) + return -ENOMEM; + + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, 0, + pattr->id, virt_to_phys(t_buf), + sizeof(*t_buf)); + + if (ret != H_SUCCESS) { + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO"); + goto out; + } + + data_offset = be64_to_cpu(t_buf->array_offset) - + (sizeof(t_buf->num_attr) + + sizeof(t_buf->array_offset) + + sizeof(t_buf->data_header_version)); + + t_ea = (struct energy_scale_attributes *) &t_buf->data[data_offset]; + + ret = sprintf(buf, "%llu\n", be64_to_cpu(t_ea->attr_value)); + if (ret < 0) + ret = -EIO; +out: + kfree(t_buf); + + return ret; +} + +static ssize_t papr_show_value_desc(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + struct papr_attr *pattr = container_of(attr, struct papr_attr, attr); + struct hv_energy_scale_buffer *t_buf; + struct energy_scale_attributes *t_ea; + int data_offset, ret = 0; + + t_buf = kmalloc(sizeof(*t_buf), GFP_KERNEL); + if (t_buf == NULL) + return -ENOMEM; + + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, 0, + pattr->id, virt_to_phys(t_buf), + sizeof(*t_buf)); + + if (ret != H_SUCCESS) { + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO"); + goto out; + } + + data_offset = be64_to_cpu(t_buf->array_offset) - + (sizeof(t_buf->num_attr) + + sizeof(t_buf->array_offset) + + sizeof(t_buf->data_header_version)); + + t_ea = (struct energy_scale_attributes *) &t_buf->data[data_offset]; + + ret = sprintf(buf, "%s\n", t_ea->attr_value_desc); + if (ret < 0) + ret = -EIO; +out: + kfree(t_buf); + + return ret; +} + +static struct papr_ops_info { + const char *attr_name; + ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, + char *buf); +} ops_info[] = { + { "desc", papr_show_desc }, + { "value", papr_show_value }, + { "value_desc", papr_show_value_desc }, +}; + +static void add_attr(u64 id, int index, struct papr_attr *attr) +{ + attr->id = id; + sysfs_attr_init(&attr->attr.attr); + attr->attr.attr.name = ops_info[index].attr_name; + attr->attr.attr.mode = 0444; + attr->attr.show = ops_info[index].show; +} + +static int add_attr_group(u64 id, int len, struct papr_group *pg, + bool show_val_desc) +{ + int i; + + for (i = 0; i < len; 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].attr.attr; + } + + return sysfs_create_group(escale_kobj, &pg->pg); +} + + +static int __init papr_init(void) +{ + uint64_t num_attr; + int ret, idx, i, data_offset; + + em_buf = kmalloc(sizeof(*em_buf), GFP_KERNEL); + if (em_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 + */ + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, 0, 0, + virt_to_phys(em_buf), sizeof(*em_buf)); + + if (!firmware_has_feature(FW_FEATURE_LPAR) || ret != H_SUCCESS || + em_buf->data_header_version != 0x1) { + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO"); + goto out; + } + + num_attr = be64_to_cpu(em_buf->num_attr); + + /* + * Typecast the energy buffer to the attribute structure at the offset + * specified in the buffer + */ + data_offset = be64_to_cpu(em_buf->array_offset) - + (sizeof(em_buf->num_attr) + + sizeof(em_buf->array_offset) + + sizeof(em_buf->data_header_version)); + + ea = (struct energy_scale_attributes *) &em_buf->data[data_offset]; + + pgs = kcalloc(num_attr, sizeof(*pgs), GFP_KERNEL); + if (!pgs) + goto out_pgs; + + papr_kobj = kobject_create_and_add("papr", firmware_kobj); + if (!papr_kobj) { + pr_warn("kobject_create_and_add papr failed\n"); + goto out_kobj; + } + + escale_kobj = kobject_create_and_add("energy_scale_info", papr_kobj); + if (!escale_kobj) { + pr_warn("kobject_create_and_add energy_scale_info failed\n"); + goto out_ekobj; + } + + for (idx = 0; idx < num_attr; idx++) { + char buf[4]; + bool show_val_desc = true; + + pgs[idx].pgattrs = kcalloc(MAX_ATTRS, + sizeof(*pgs[idx].pgattrs), + GFP_KERNEL); + if (!pgs[idx].pgattrs) + goto out_kobj; + + pgs[idx].pg.attrs = kcalloc(MAX_ATTRS + 1, + sizeof(*pgs[idx].pg.attrs), + GFP_KERNEL); + if (!pgs[idx].pg.attrs) { + kfree(pgs[idx].pgattrs); + goto out_kobj; + } + + sprintf(buf, "%lld", be64_to_cpu(ea[idx].attr_id)); + pgs[idx].pg.name = buf; + + /* Do not add the value description if it does not exist */ + if (strlen(ea[idx].attr_value_desc) == 0) + show_val_desc = false; + + if (add_attr_group(be64_to_cpu(ea[idx].attr_id), + MAX_ATTRS, &pgs[idx], show_val_desc)) { + pr_warn("Failed to create papr attribute group %s\n", + pgs[idx].pg.name); + goto out_pgattrs; + } + } + + return 0; + +out_pgattrs: + for (i = 0; i < MAX_ATTRS; i++) { + kfree(pgs[i].pgattrs); + kfree(pgs[i].pg.attrs); + } +out_ekobj: + kobject_put(escale_kobj); +out_kobj: + kobject_put(papr_kobj); +out_pgs: + kfree(pgs); +out: + kfree(em_buf); + + return -ENOMEM; +} + +machine_device_initcall(pseries, papr_init); -- 2.30.2