// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2005 Intel Corporation * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. * * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> * - Added _PDC for platforms with Intel CPUs */ #define pr_fmt(fmt) "ACPI: " fmt #include <linux/dmi.h> #include <linux/slab.h> #include <linux/acpi.h> #include <acpi/processor.h> #include "internal.h" static bool __init processor_physically_present(acpi_handle handle) { int cpuid, type; 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 }; status = acpi_get_type(handle, &acpi_type); if (ACPI_FAILURE(status)) return false; switch (acpi_type) { case ACPI_TYPE_PROCESSOR: status = acpi_evaluate_object(handle, NULL, NULL, &buffer); if (ACPI_FAILURE(status)) return false; acpi_id = object.processor.proc_id; break; case ACPI_TYPE_DEVICE: status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp); if (ACPI_FAILURE(status)) return false; acpi_id = tmp; break; default: return false; } type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0; cpuid = acpi_get_cpuid(handle, type, acpi_id); return !invalid_logical_cpuid(cpuid); } static void acpi_set_pdc_bits(u32 *buf) { buf[0] = ACPI_PDC_REVISION_ID; buf[1] = 1; /* Enable coordination with firmware's _TSD info */ buf[2] = ACPI_PDC_SMP_T_SWCOORD; /* Twiddle arch-specific bits needed for _PDC */ arch_acpi_set_pdc_bits(buf); } static struct acpi_object_list *acpi_processor_alloc_pdc(void) { struct acpi_object_list *obj_list; union acpi_object *obj; u32 *buf; /* allocate and initialize pdc. It will be used later. */ obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL); if (!obj_list) goto out; obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL); if (!obj) { kfree(obj_list); goto out; } buf = kmalloc(12, GFP_KERNEL); if (!buf) { kfree(obj); kfree(obj_list); goto out; } acpi_set_pdc_bits(buf); obj->type = ACPI_TYPE_BUFFER; obj->buffer.length = 12; obj->buffer.pointer = (u8 *) buf; obj_list->count = 1; obj_list->pointer = obj; return obj_list; out: pr_err("Memory allocation error\n"); return NULL; } /* * _PDC is required for a BIOS-OS handshake for most of the newer * ACPI processor features. */ static acpi_status acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in) { acpi_status status = AE_OK; if (boot_option_idle_override == IDLE_NOMWAIT) { /* * If mwait is disabled for CPU C-states, the C2C3_FFH access * mode will be disabled in the parameter of _PDC object. * Of course C1_FFH access mode will also be disabled. */ union acpi_object *obj; u32 *buffer = NULL; obj = pdc_in->pointer; buffer = (u32 *)(obj->buffer.pointer); buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH); } status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL); if (ACPI_FAILURE(status)) acpi_handle_debug(handle, "Could not evaluate _PDC, using legacy perf control\n"); return status; } void acpi_processor_set_pdc(acpi_handle handle) { struct acpi_object_list *obj_list; if (arch_has_acpi_pdc() == false) return; obj_list = acpi_processor_alloc_pdc(); if (!obj_list) return; acpi_processor_eval_pdc(handle, obj_list); kfree(obj_list->pointer->buffer.pointer); kfree(obj_list->pointer); kfree(obj_list); } static acpi_status __init early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv) { if (processor_physically_present(handle) == false) return AE_OK; acpi_processor_set_pdc(handle); return AE_OK; } static int __init set_no_mwait(const struct dmi_system_id *id) { pr_notice("%s detected - disabling mwait for CPU C-states\n", id->ident); boot_option_idle_override = IDLE_NOMWAIT; return 0; } static const struct dmi_system_id processor_idle_dmi_table[] __initconst = { { set_no_mwait, "Extensa 5220", { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"), DMI_MATCH(DMI_SYS_VENDOR, "Acer"), DMI_MATCH(DMI_PRODUCT_VERSION, "0100"), DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL}, {}, }; static void __init processor_dmi_check(void) { /* * Check whether the system is DMI table. If yes, OSPM * should not use mwait for CPU-states. */ dmi_check_system(processor_idle_dmi_table); } void __init acpi_early_processor_set_pdc(void) { processor_dmi_check(); acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX, early_init_pdc, NULL, NULL, NULL); acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, early_init_pdc, NULL, NULL); }