| /* |
| * Copyright 2012 by Oracle Inc |
| * Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
| * |
| * This code borrows ideas from https://lkml.org/lkml/2011/11/30/249 |
| * so many thanks go to Kevin Tian <kevin.tian@intel.com> |
| * and Yu Ke <ke.yu@intel.com>. |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms and conditions of the GNU General Public License, |
| * version 2, as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| * more details. |
| * |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/cpumask.h> |
| #include <linux/cpufreq.h> |
| #include <linux/freezer.h> |
| #include <linux/kernel.h> |
| #include <linux/kthread.h> |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/types.h> |
| #include <linux/acpi.h> |
| #include <acpi/processor.h> |
| #include <xen/xen.h> |
| #include <xen/xen-ops.h> |
| #include <xen/interface/platform.h> |
| #include <asm/xen/hypercall.h> |
| |
| static int no_hypercall; |
| MODULE_PARM_DESC(off, "Inhibit the hypercall."); |
| module_param_named(off, no_hypercall, int, 0400); |
| |
| /* |
| * Note: Do not convert the acpi_id* below to cpumask_var_t or use cpumask_bit |
| * - as those shrink to nr_cpu_bits (which is dependent on possible_cpu), which |
| * can be less than what we want to put in. Instead use the 'nr_acpi_bits' |
| * which is dynamically computed based on the MADT or x2APIC table. |
| */ |
| static unsigned int nr_acpi_bits; |
| /* Mutex to protect the acpi_ids_done - for CPU hotplug use. */ |
| static DEFINE_MUTEX(acpi_ids_mutex); |
| /* Which ACPI ID we have processed from 'struct acpi_processor'. */ |
| static unsigned long *acpi_ids_done; |
| /* Which ACPI ID exist in the SSDT/DSDT processor definitions. */ |
| static unsigned long *acpi_id_present; |
| /* And if there is an _CST definition (or a PBLK) for the ACPI IDs */ |
| static unsigned long *acpi_id_cst_present; |
| |
| static int push_cxx_to_hypervisor(struct acpi_processor *_pr) |
| { |
| struct xen_platform_op op = { |
| .cmd = XENPF_set_processor_pminfo, |
| .interface_version = XENPF_INTERFACE_VERSION, |
| .u.set_pminfo.id = _pr->acpi_id, |
| .u.set_pminfo.type = XEN_PM_CX, |
| }; |
| struct xen_processor_cx *dst_cx, *dst_cx_states = NULL; |
| struct acpi_processor_cx *cx; |
| unsigned int i, ok; |
| int ret = 0; |
| |
| dst_cx_states = kcalloc(_pr->power.count, |
| sizeof(struct xen_processor_cx), GFP_KERNEL); |
| if (!dst_cx_states) |
| return -ENOMEM; |
| |
| for (ok = 0, i = 1; i <= _pr->power.count; i++) { |
| cx = &_pr->power.states[i]; |
| if (!cx->valid) |
| continue; |
| |
| dst_cx = &(dst_cx_states[ok++]); |
| |
| dst_cx->reg.space_id = ACPI_ADR_SPACE_SYSTEM_IO; |
| if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) { |
| dst_cx->reg.bit_width = 8; |
| dst_cx->reg.bit_offset = 0; |
| dst_cx->reg.access_size = 1; |
| } else { |
| dst_cx->reg.space_id = ACPI_ADR_SPACE_FIXED_HARDWARE; |
| if (cx->entry_method == ACPI_CSTATE_FFH) { |
| /* NATIVE_CSTATE_BEYOND_HALT */ |
| dst_cx->reg.bit_offset = 2; |
| dst_cx->reg.bit_width = 1; /* VENDOR_INTEL */ |
| } |
| dst_cx->reg.access_size = 0; |
| } |
| dst_cx->reg.address = cx->address; |
| |
| dst_cx->type = cx->type; |
| dst_cx->latency = cx->latency; |
| |
| dst_cx->dpcnt = 0; |
| set_xen_guest_handle(dst_cx->dp, NULL); |
| } |
| if (!ok) { |
| pr_debug("No _Cx for ACPI CPU %u\n", _pr->acpi_id); |
| kfree(dst_cx_states); |
| return -EINVAL; |
| } |
| op.u.set_pminfo.power.count = ok; |
| op.u.set_pminfo.power.flags.bm_control = _pr->flags.bm_control; |
| op.u.set_pminfo.power.flags.bm_check = _pr->flags.bm_check; |
| op.u.set_pminfo.power.flags.has_cst = _pr->flags.has_cst; |
| op.u.set_pminfo.power.flags.power_setup_done = |
| _pr->flags.power_setup_done; |
| |
| set_xen_guest_handle(op.u.set_pminfo.power.states, dst_cx_states); |
| |
| if (!no_hypercall) |
| ret = HYPERVISOR_platform_op(&op); |
| |
| if (!ret) { |
| pr_debug("ACPI CPU%u - C-states uploaded.\n", _pr->acpi_id); |
| for (i = 1; i <= _pr->power.count; i++) { |
| cx = &_pr->power.states[i]; |
| if (!cx->valid) |
| continue; |
| pr_debug(" C%d: %s %d uS\n", |
| cx->type, cx->desc, (u32)cx->latency); |
| } |
| } else if ((ret != -EINVAL) && (ret != -ENOSYS)) |
| /* EINVAL means the ACPI ID is incorrect - meaning the ACPI |
| * table is referencing a non-existing CPU - which can happen |
| * with broken ACPI tables. */ |
| pr_err("(CX): Hypervisor error (%d) for ACPI CPU%u\n", |
| ret, _pr->acpi_id); |
| |
| kfree(dst_cx_states); |
| |
| return ret; |
| } |
| static struct xen_processor_px * |
| xen_copy_pss_data(struct acpi_processor *_pr, |
| struct xen_processor_performance *dst_perf) |
| { |
| struct xen_processor_px *dst_states = NULL; |
| unsigned int i; |
| |
| BUILD_BUG_ON(sizeof(struct xen_processor_px) != |
| sizeof(struct acpi_processor_px)); |
| |
| dst_states = kcalloc(_pr->performance->state_count, |
| sizeof(struct xen_processor_px), GFP_KERNEL); |
| if (!dst_states) |
| return ERR_PTR(-ENOMEM); |
| |
| dst_perf->state_count = _pr->performance->state_count; |
| for (i = 0; i < _pr->performance->state_count; i++) { |
| /* Fortunatly for us, they are both the same size */ |
| memcpy(&(dst_states[i]), &(_pr->performance->states[i]), |
| sizeof(struct acpi_processor_px)); |
| } |
| return dst_states; |
| } |
| static int xen_copy_psd_data(struct acpi_processor *_pr, |
| struct xen_processor_performance *dst) |
| { |
| struct acpi_psd_package *pdomain; |
| |
| BUILD_BUG_ON(sizeof(struct xen_psd_package) != |
| sizeof(struct acpi_psd_package)); |
| |
| /* This information is enumerated only if acpi_processor_preregister_performance |
| * has been called. |
| */ |
| dst->shared_type = _pr->performance->shared_type; |
| |
| pdomain = &(_pr->performance->domain_info); |
| |
| /* 'acpi_processor_preregister_performance' does not parse if the |
| * num_processors <= 1, but Xen still requires it. Do it manually here. |
| */ |
| if (pdomain->num_processors <= 1) { |
| if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL) |
| dst->shared_type = CPUFREQ_SHARED_TYPE_ALL; |
| else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL) |
| dst->shared_type = CPUFREQ_SHARED_TYPE_HW; |
| else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY) |
| dst->shared_type = CPUFREQ_SHARED_TYPE_ANY; |
| |
| } |
| memcpy(&(dst->domain_info), pdomain, sizeof(struct acpi_psd_package)); |
| return 0; |
| } |
| static int xen_copy_pct_data(struct acpi_pct_register *pct, |
| struct xen_pct_register *dst_pct) |
| { |
| /* It would be nice if you could just do 'memcpy(pct, dst_pct') but |
| * sadly the Xen structure did not have the proper padding so the |
| * descriptor field takes two (dst_pct) bytes instead of one (pct). |
| */ |
| dst_pct->descriptor = pct->descriptor; |
| dst_pct->length = pct->length; |
| dst_pct->space_id = pct->space_id; |
| dst_pct->bit_width = pct->bit_width; |
| dst_pct->bit_offset = pct->bit_offset; |
| dst_pct->reserved = pct->reserved; |
| dst_pct->address = pct->address; |
| return 0; |
| } |
| static int push_pxx_to_hypervisor(struct acpi_processor *_pr) |
| { |
| int ret = 0; |
| struct xen_platform_op op = { |
| .cmd = XENPF_set_processor_pminfo, |
| .interface_version = XENPF_INTERFACE_VERSION, |
| .u.set_pminfo.id = _pr->acpi_id, |
| .u.set_pminfo.type = XEN_PM_PX, |
| }; |
| struct xen_processor_performance *dst_perf; |
| struct xen_processor_px *dst_states = NULL; |
| |
| dst_perf = &op.u.set_pminfo.perf; |
| |
| dst_perf->platform_limit = _pr->performance_platform_limit; |
| dst_perf->flags |= XEN_PX_PPC; |
| xen_copy_pct_data(&(_pr->performance->control_register), |
| &dst_perf->control_register); |
| xen_copy_pct_data(&(_pr->performance->status_register), |
| &dst_perf->status_register); |
| dst_perf->flags |= XEN_PX_PCT; |
| dst_states = xen_copy_pss_data(_pr, dst_perf); |
| if (!IS_ERR_OR_NULL(dst_states)) { |
| set_xen_guest_handle(dst_perf->states, dst_states); |
| dst_perf->flags |= XEN_PX_PSS; |
| } |
| if (!xen_copy_psd_data(_pr, dst_perf)) |
| dst_perf->flags |= XEN_PX_PSD; |
| |
| if (dst_perf->flags != (XEN_PX_PSD | XEN_PX_PSS | XEN_PX_PCT | XEN_PX_PPC)) { |
| pr_warn("ACPI CPU%u missing some P-state data (%x), skipping\n", |
| _pr->acpi_id, dst_perf->flags); |
| ret = -ENODEV; |
| goto err_free; |
| } |
| |
| if (!no_hypercall) |
| ret = HYPERVISOR_platform_op(&op); |
| |
| if (!ret) { |
| struct acpi_processor_performance *perf; |
| unsigned int i; |
| |
| perf = _pr->performance; |
| pr_debug("ACPI CPU%u - P-states uploaded.\n", _pr->acpi_id); |
| for (i = 0; i < perf->state_count; i++) { |
| pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n", |
| (i == perf->state ? '*' : ' '), i, |
| (u32) perf->states[i].core_frequency, |
| (u32) perf->states[i].power, |
| (u32) perf->states[i].transition_latency); |
| } |
| } else if ((ret != -EINVAL) && (ret != -ENOSYS)) |
| /* EINVAL means the ACPI ID is incorrect - meaning the ACPI |
| * table is referencing a non-existing CPU - which can happen |
| * with broken ACPI tables. */ |
| pr_warn("(_PXX): Hypervisor error (%d) for ACPI CPU%u\n", |
| ret, _pr->acpi_id); |
| err_free: |
| if (!IS_ERR_OR_NULL(dst_states)) |
| kfree(dst_states); |
| |
| return ret; |
| } |
| static int upload_pm_data(struct acpi_processor *_pr) |
| { |
| int err = 0; |
| |
| mutex_lock(&acpi_ids_mutex); |
| if (__test_and_set_bit(_pr->acpi_id, acpi_ids_done)) { |
| mutex_unlock(&acpi_ids_mutex); |
| return -EBUSY; |
| } |
| if (_pr->flags.power) |
| err = push_cxx_to_hypervisor(_pr); |
| |
| if (_pr->performance && _pr->performance->states) |
| err |= push_pxx_to_hypervisor(_pr); |
| |
| mutex_unlock(&acpi_ids_mutex); |
| return err; |
| } |
| static unsigned int __init get_max_acpi_id(void) |
| { |
| struct xenpf_pcpuinfo *info; |
| struct xen_platform_op op = { |
| .cmd = XENPF_get_cpuinfo, |
| .interface_version = XENPF_INTERFACE_VERSION, |
| }; |
| int ret = 0; |
| unsigned int i, last_cpu, max_acpi_id = 0; |
| |
| info = &op.u.pcpu_info; |
| info->xen_cpuid = 0; |
| |
| ret = HYPERVISOR_platform_op(&op); |
| if (ret) |
| return NR_CPUS; |
| |
| /* The max_present is the same irregardless of the xen_cpuid */ |
| last_cpu = op.u.pcpu_info.max_present; |
| for (i = 0; i <= last_cpu; i++) { |
| info->xen_cpuid = i; |
| ret = HYPERVISOR_platform_op(&op); |
| if (ret) |
| continue; |
| max_acpi_id = max(info->acpi_id, max_acpi_id); |
| } |
| max_acpi_id *= 2; /* Slack for CPU hotplug support. */ |
| pr_debug("Max ACPI ID: %u\n", max_acpi_id); |
| return max_acpi_id; |
| } |
| /* |
| * The read_acpi_id and check_acpi_ids are there to support the Xen |
| * oddity of virtual CPUs != physical CPUs in the initial domain. |
| * The user can supply 'xen_max_vcpus=X' on the Xen hypervisor line |
| * which will band the amount of CPUs the initial domain can see. |
| * In general that is OK, except it plays havoc with any of the |
| * for_each_[present|online]_cpu macros which are banded to the virtual |
| * CPU amount. |
| */ |
| static acpi_status |
| read_acpi_id(acpi_handle handle, u32 lvl, void *context, void **rv) |
| { |
| u32 acpi_id; |
| acpi_status status; |
| acpi_object_type acpi_type; |
| unsigned long long tmp; |
| union acpi_object object = { 0 }; |
| struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; |
| acpi_io_address pblk = 0; |
| |
| status = acpi_get_type(handle, &acpi_type); |
| if (ACPI_FAILURE(status)) |
| return AE_OK; |
| |
| switch (acpi_type) { |
| case ACPI_TYPE_PROCESSOR: |
| status = acpi_evaluate_object(handle, NULL, NULL, &buffer); |
| if (ACPI_FAILURE(status)) |
| return AE_OK; |
| acpi_id = object.processor.proc_id; |
| pblk = object.processor.pblk_address; |
| break; |
| case ACPI_TYPE_DEVICE: |
| status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp); |
| if (ACPI_FAILURE(status)) |
| return AE_OK; |
| acpi_id = tmp; |
| break; |
| default: |
| return AE_OK; |
| } |
| /* There are more ACPI Processor objects than in x2APIC or MADT. |
| * This can happen with incorrect ACPI SSDT declerations. */ |
| if (acpi_id > nr_acpi_bits) { |
| pr_debug("We only have %u, trying to set %u\n", |
| nr_acpi_bits, acpi_id); |
| return AE_OK; |
| } |
| /* OK, There is a ACPI Processor object */ |
| __set_bit(acpi_id, acpi_id_present); |
| |
| pr_debug("ACPI CPU%u w/ PBLK:0x%lx\n", acpi_id, (unsigned long)pblk); |
| |
| status = acpi_evaluate_object(handle, "_CST", NULL, &buffer); |
| if (ACPI_FAILURE(status)) { |
| if (!pblk) |
| return AE_OK; |
| } |
| /* .. and it has a C-state */ |
| __set_bit(acpi_id, acpi_id_cst_present); |
| |
| return AE_OK; |
| } |
| static int check_acpi_ids(struct acpi_processor *pr_backup) |
| { |
| |
| if (!pr_backup) |
| return -ENODEV; |
| |
| if (acpi_id_present && acpi_id_cst_present) |
| /* OK, done this once .. skip to uploading */ |
| goto upload; |
| |
| /* All online CPUs have been processed at this stage. Now verify |
| * whether in fact "online CPUs" == physical CPUs. |
| */ |
| acpi_id_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL); |
| if (!acpi_id_present) |
| return -ENOMEM; |
| |
| acpi_id_cst_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL); |
| if (!acpi_id_cst_present) { |
| kfree(acpi_id_present); |
| return -ENOMEM; |
| } |
| |
| acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, |
| ACPI_UINT32_MAX, |
| read_acpi_id, NULL, NULL, NULL); |
| acpi_get_devices("ACPI0007", read_acpi_id, NULL, NULL); |
| |
| upload: |
| if (!bitmap_equal(acpi_id_present, acpi_ids_done, nr_acpi_bits)) { |
| unsigned int i; |
| for_each_set_bit(i, acpi_id_present, nr_acpi_bits) { |
| pr_backup->acpi_id = i; |
| /* Mask out C-states if there are no _CST or PBLK */ |
| pr_backup->flags.power = test_bit(i, acpi_id_cst_present); |
| (void)upload_pm_data(pr_backup); |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* acpi_perf_data is a pointer to percpu data. */ |
| static struct acpi_processor_performance __percpu *acpi_perf_data; |
| |
| static void free_acpi_perf_data(void) |
| { |
| unsigned int i; |
| |
| /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */ |
| for_each_possible_cpu(i) |
| free_cpumask_var(per_cpu_ptr(acpi_perf_data, i) |
| ->shared_cpu_map); |
| free_percpu(acpi_perf_data); |
| } |
| |
| static int xen_upload_processor_pm_data(void) |
| { |
| struct acpi_processor *pr_backup = NULL; |
| unsigned int i; |
| int rc = 0; |
| |
| pr_info("Uploading Xen processor PM info\n"); |
| |
| for_each_possible_cpu(i) { |
| struct acpi_processor *_pr; |
| _pr = per_cpu(processors, i /* APIC ID */); |
| if (!_pr) |
| continue; |
| |
| if (!pr_backup) { |
| pr_backup = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL); |
| if (pr_backup) |
| memcpy(pr_backup, _pr, sizeof(struct acpi_processor)); |
| } |
| (void)upload_pm_data(_pr); |
| } |
| |
| rc = check_acpi_ids(pr_backup); |
| kfree(pr_backup); |
| |
| return rc; |
| } |
| |
| static int xen_acpi_processor_resume(struct notifier_block *nb, |
| unsigned long action, void *data) |
| { |
| bitmap_zero(acpi_ids_done, nr_acpi_bits); |
| return xen_upload_processor_pm_data(); |
| } |
| |
| struct notifier_block xen_acpi_processor_resume_nb = { |
| .notifier_call = xen_acpi_processor_resume, |
| }; |
| |
| static int __init xen_acpi_processor_init(void) |
| { |
| unsigned int i; |
| int rc; |
| |
| if (!xen_initial_domain()) |
| return -ENODEV; |
| |
| nr_acpi_bits = get_max_acpi_id() + 1; |
| acpi_ids_done = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL); |
| if (!acpi_ids_done) |
| return -ENOMEM; |
| |
| acpi_perf_data = alloc_percpu(struct acpi_processor_performance); |
| if (!acpi_perf_data) { |
| pr_debug("Memory allocation error for acpi_perf_data\n"); |
| kfree(acpi_ids_done); |
| return -ENOMEM; |
| } |
| for_each_possible_cpu(i) { |
| if (!zalloc_cpumask_var_node( |
| &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map, |
| GFP_KERNEL, cpu_to_node(i))) { |
| rc = -ENOMEM; |
| goto err_out; |
| } |
| } |
| |
| /* Do initialization in ACPI core. It is OK to fail here. */ |
| (void)acpi_processor_preregister_performance(acpi_perf_data); |
| |
| for_each_possible_cpu(i) { |
| struct acpi_processor *pr; |
| struct acpi_processor_performance *perf; |
| |
| pr = per_cpu(processors, i); |
| perf = per_cpu_ptr(acpi_perf_data, i); |
| if (!pr) |
| continue; |
| |
| pr->performance = perf; |
| rc = acpi_processor_get_performance_info(pr); |
| if (rc) |
| goto err_out; |
| } |
| |
| rc = xen_upload_processor_pm_data(); |
| if (rc) |
| goto err_unregister; |
| |
| xen_resume_notifier_register(&xen_acpi_processor_resume_nb); |
| |
| return 0; |
| err_unregister: |
| for_each_possible_cpu(i) |
| acpi_processor_unregister_performance(i); |
| |
| err_out: |
| /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */ |
| free_acpi_perf_data(); |
| kfree(acpi_ids_done); |
| return rc; |
| } |
| static void __exit xen_acpi_processor_exit(void) |
| { |
| int i; |
| |
| xen_resume_notifier_unregister(&xen_acpi_processor_resume_nb); |
| kfree(acpi_ids_done); |
| kfree(acpi_id_present); |
| kfree(acpi_id_cst_present); |
| for_each_possible_cpu(i) |
| acpi_processor_unregister_performance(i); |
| |
| free_acpi_perf_data(); |
| } |
| |
| MODULE_AUTHOR("Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>"); |
| MODULE_DESCRIPTION("Xen ACPI Processor P-states (and Cx) driver which uploads PM data to Xen hypervisor"); |
| MODULE_LICENSE("GPL"); |
| |
| /* We want to be loaded before the CPU freq scaling drivers are loaded. |
| * They are loaded in late_initcall. */ |
| device_initcall(xen_acpi_processor_init); |
| module_exit(xen_acpi_processor_exit); |