diff options
Diffstat (limited to 'drivers/acpi/acpi_processor.c')
| -rw-r--r-- | drivers/acpi/acpi_processor.c | 604 |
1 files changed, 449 insertions, 155 deletions
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index f098e25b6b41..7ec1dc04fd11 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * acpi_processor.c - ACPI processor enumeration support * @@ -7,38 +8,44 @@ * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> * Copyright (C) 2013, Intel Corporation * Rafael J. Wysocki <rafael.j.wysocki@intel.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 as published - * by the Free Software Foundation. */ +#define pr_fmt(fmt) "ACPI: " fmt #include <linux/acpi.h> +#include <linux/cpu.h> #include <linux/device.h> +#include <linux/dmi.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/pci.h> +#include <linux/platform_device.h> #include <acpi/processor.h> #include <asm/cpu.h> -#include "internal.h" - -#define _COMPONENT ACPI_PROCESSOR_COMPONENT +#include <xen/xen.h> -ACPI_MODULE_NAME("processor"); +#include "internal.h" DEFINE_PER_CPU(struct acpi_processor *, processors); EXPORT_PER_CPU_SYMBOL(processors); -/* -------------------------------------------------------------------------- - Errata Handling - -------------------------------------------------------------------------- */ - +/* Errata Handling */ struct acpi_processor_errata errata __read_mostly; EXPORT_SYMBOL_GPL(errata); +acpi_handle acpi_get_processor_handle(int cpu) +{ + struct acpi_processor *pr; + + pr = per_cpu(processors, cpu); + if (pr) + return pr->handle; + + return NULL; +} + static int acpi_processor_errata_piix4(struct pci_dev *dev) { u8 value1 = 0; @@ -54,19 +61,19 @@ static int acpi_processor_errata_piix4(struct pci_dev *dev) switch (dev->revision) { case 0: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n")); + dev_dbg(&dev->dev, "Found PIIX4 A-step\n"); break; case 1: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n")); + dev_dbg(&dev->dev, "Found PIIX4 B-step\n"); break; case 2: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n")); + dev_dbg(&dev->dev, "Found PIIX4E\n"); break; case 3: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n")); + dev_dbg(&dev->dev, "Found PIIX4M\n"); break; default: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n")); + dev_dbg(&dev->dev, "Found unknown PIIX4\n"); break; } @@ -82,6 +89,7 @@ static int acpi_processor_errata_piix4(struct pci_dev *dev) * PIIX4 models. */ errata.piix4.throttle = 1; + fallthrough; case 2: /* PIIX4E */ case 3: /* PIIX4M */ @@ -131,11 +139,9 @@ static int acpi_processor_errata_piix4(struct pci_dev *dev) } if (errata.piix4.bmisx) - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Bus master activity detection (BM-IDE) erratum enabled\n")); + dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n"); if (errata.piix4.fdma) - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Type-F DMA livelock erratum (C3 disabled)\n")); + dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n"); return 0; } @@ -159,70 +165,109 @@ static int acpi_processor_errata(void) return result; } -/* -------------------------------------------------------------------------- - Initialization - -------------------------------------------------------------------------- */ - -#ifdef CONFIG_ACPI_HOTPLUG_CPU -int __weak acpi_map_cpu(acpi_handle handle, - phys_cpuid_t physid, u32 acpi_id, int *pcpu) +/* Create a platform device to represent a CPU frequency control mechanism. */ +static void cpufreq_add_device(const char *name) { - return -ENODEV; + struct platform_device *pdev; + + pdev = platform_device_register_simple(name, PLATFORM_DEVID_NONE, NULL, 0); + if (IS_ERR(pdev)) + pr_info("%s device creation failed: %pe\n", name, pdev); } -int __weak acpi_unmap_cpu(int cpu) +#ifdef CONFIG_X86 +/* Check presence of Processor Clocking Control by searching for \_SB.PCCH. */ +static void __init acpi_pcc_cpufreq_init(void) { - return -ENODEV; + acpi_status status; + acpi_handle handle; + + status = acpi_get_handle(NULL, "\\_SB", &handle); + if (ACPI_FAILURE(status)) + return; + + if (acpi_has_method(handle, "PCCH")) + cpufreq_add_device("pcc-cpufreq"); } +#else +static void __init acpi_pcc_cpufreq_init(void) {} +#endif /* CONFIG_X86 */ + +/* Initialization */ +static DEFINE_PER_CPU(void *, processor_device_array); -int __weak arch_register_cpu(int cpu) +static int acpi_processor_set_per_cpu(struct acpi_processor *pr, + struct acpi_device *device) { - return -ENODEV; -} + BUG_ON(pr->id >= nr_cpu_ids); -void __weak arch_unregister_cpu(int cpu) {} + /* + * Buggy BIOS check. + * ACPI id of processors can be reported wrongly by the BIOS. + * Don't trust it blindly + */ + if (per_cpu(processor_device_array, pr->id) != NULL && + per_cpu(processor_device_array, pr->id) != device) { + dev_warn(&device->dev, + "BIOS reported wrong ACPI id %d for the processor\n", + pr->id); + return -EINVAL; + } + /* + * processor_device_array is not cleared on errors to allow buggy BIOS + * checks. + */ + per_cpu(processor_device_array, pr->id) = device; + per_cpu(processors, pr->id) = pr; -static int acpi_processor_hotadd_init(struct acpi_processor *pr) + return 0; +} + +#ifdef CONFIG_ACPI_HOTPLUG_CPU +static int acpi_processor_hotadd_init(struct acpi_processor *pr, + struct acpi_device *device) { - unsigned long long sta; - acpi_status status; int ret; if (invalid_phys_cpuid(pr->phys_id)) return -ENODEV; - status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta); - if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT)) - return -ENODEV; - cpu_maps_update_begin(); - cpu_hotplug_begin(); + cpus_write_lock(); ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id); if (ret) goto out; + ret = acpi_processor_set_per_cpu(pr, device); + if (ret) { + acpi_unmap_cpu(pr->id); + goto out; + } + ret = arch_register_cpu(pr->id); if (ret) { + /* Leave the processor device array in place to detect buggy bios */ + per_cpu(processors, pr->id) = NULL; acpi_unmap_cpu(pr->id); goto out; } /* - * CPU got hot-added, but cpu_data is not initialized yet. Set a flag - * to delay cpu_idle/throttling initialization and do it when the CPU - * gets online for the first time. + * CPU got hot-added, but cpu_data is not initialized yet. Do + * cpu_idle/throttling initialization when the CPU gets online for + * the first time. */ pr_info("CPU%d has been hot-added\n", pr->id); - pr->flags.need_hotplug_init = 1; out: - cpu_hotplug_done(); + cpus_write_unlock(); cpu_maps_update_done(); return ret; } #else -static inline int acpi_processor_hotadd_init(struct acpi_processor *pr) +static inline int acpi_processor_hotadd_init(struct acpi_processor *pr, + struct acpi_device *device) { return -ENODEV; } @@ -230,13 +275,14 @@ static inline int acpi_processor_hotadd_init(struct acpi_processor *pr) static int acpi_processor_get_info(struct acpi_device *device) { - union acpi_object object = { 0 }; + union acpi_object object = { .processor = { 0 } }; struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; struct acpi_processor *pr = acpi_driver_data(device); int device_declaration = 0; acpi_status status = AE_OK; static int cpu0_initialized; unsigned long long value; + int ret; acpi_processor_errata(); @@ -246,11 +292,9 @@ static int acpi_processor_get_info(struct acpi_device *device) */ if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) { pr->flags.bm_control = 1; - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Bus mastering arbitration control present\n")); + dev_dbg(&device->dev, "Bus mastering arbitration control present\n"); } else - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "No bus mastering arbitration control\n")); + dev_dbg(&device->dev, "No bus mastering arbitration control\n"); if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) { /* Declared with "Processor" statement; match ProcessorID */ @@ -266,7 +310,6 @@ static int acpi_processor_get_info(struct acpi_device *device) } else { /* * Declared with "Device" statement; match _UID. - * Note that we don't handle string _UIDs yet. */ status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID, NULL, &value); @@ -281,41 +324,54 @@ static int acpi_processor_get_info(struct acpi_device *device) } if (acpi_duplicate_processor_id(pr->acpi_id)) { - dev_err(&device->dev, - "Failed to get unique processor _UID (0x%x)\n", - pr->acpi_id); + if (pr->acpi_id == 0xff) + dev_info_once(&device->dev, + "Entry not well-defined, consider updating BIOS\n"); + else + dev_err(&device->dev, + "Failed to get unique processor _UID (0x%x)\n", + pr->acpi_id); return -ENODEV; } pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration, pr->acpi_id); if (invalid_phys_cpuid(pr->phys_id)) - acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n"); + dev_dbg(&device->dev, "Failed to get CPU physical ID.\n"); pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id); - if (!cpu0_initialized && !acpi_has_cpu_in_madt()) { + if (!cpu0_initialized) { cpu0_initialized = 1; /* * Handle UP system running SMP kernel, with no CPU * entry in MADT */ - if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1)) + if (!acpi_has_cpu_in_madt() && invalid_logical_cpuid(pr->id) && + (num_online_cpus() == 1)) pr->id = 0; + /* + * Check availability of Processor Performance Control by + * looking at the presence of the _PCT object under the first + * processor definition. + */ + if (acpi_has_method(pr->handle, "_PCT")) + cpufreq_add_device("acpi-cpufreq"); } /* - * Extra Processor objects may be enumerated on MP systems with - * less than the max # of CPUs. They should be ignored _iff - * they are physically not present. - * - * NOTE: Even if the processor has a cpuid, it may not be present - * because cpuid <-> apicid mapping is persistent now. + * This code is not called unless we know the CPU is present and + * enabled. The two paths are: + * a) Initially present CPUs on architectures that do not defer + * their arch_register_cpu() calls until this point. + * b) Hotplugged CPUs (enabled bit in _STA has transitioned from not + * enabled to enabled) */ - if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) { - int ret = acpi_processor_hotadd_init(pr); - if (ret) - return ret; - } + if (!get_cpu_device(pr->id)) + ret = acpi_processor_hotadd_init(pr, device); + else + ret = acpi_processor_set_per_cpu(pr, device); + if (ret) + return ret; /* * On some boxes several processors use the same processor bus id. @@ -327,11 +383,10 @@ static int acpi_processor_get_info(struct acpi_device *device) * CPU+CPU ID. */ sprintf(acpi_device_bid(device), "CPU%X", pr->id); - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id, - pr->acpi_id)); + dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id); if (!object.processor.pblk_address) - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n")); + dev_dbg(&device->dev, "No PBLK (NULL address)\n"); else if (object.processor.pblk_length != 6) dev_err(&device->dev, "Invalid PBLK length [%d]\n", object.processor.pblk_length); @@ -361,8 +416,6 @@ static int acpi_processor_get_info(struct acpi_device *device) * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc. * Such things have to be put in and set up by the processor driver's .probe(). */ -static DEFINE_PER_CPU(void *, processor_device_array); - static int acpi_processor_add(struct acpi_device *device, const struct acpi_device_id *id) { @@ -370,6 +423,9 @@ static int acpi_processor_add(struct acpi_device *device, struct device *dev; int result = 0; + if (!acpi_device_is_enabled(device)) + return -ENODEV; + pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL); if (!pr) return -ENOMEM; @@ -380,45 +436,23 @@ static int acpi_processor_add(struct acpi_device *device, } pr->handle = device->handle; - strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME); - strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS); + strscpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME); + strscpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS); device->driver_data = pr; result = acpi_processor_get_info(device); if (result) /* Processor is not physically present or unavailable */ - return 0; - - BUG_ON(pr->id >= nr_cpu_ids); - - /* - * Buggy BIOS check. - * ACPI id of processors can be reported wrongly by the BIOS. - * Don't trust it blindly - */ - if (per_cpu(processor_device_array, pr->id) != NULL && - per_cpu(processor_device_array, pr->id) != device) { - dev_warn(&device->dev, - "BIOS reported wrong ACPI id %d for the processor\n", - pr->id); - /* Give up, but do not abort the namespace scan. */ - goto err; - } - /* - * processor_device_array is not cleared on errors to allow buggy BIOS - * checks. - */ - per_cpu(processor_device_array, pr->id) = device; - per_cpu(processors, pr->id) = pr; + goto err_clear_driver_data; dev = get_cpu_device(pr->id); if (!dev) { result = -ENODEV; - goto err; + goto err_clear_per_cpu; } result = acpi_bind_one(dev, device); if (result) - goto err; + goto err_clear_per_cpu; pr->dev = dev; @@ -429,21 +463,19 @@ static int acpi_processor_add(struct acpi_device *device, dev_err(dev, "Processor driver could not be attached\n"); acpi_unbind_one(dev); - err: - free_cpumask_var(pr->throttling.shared_cpu_map); - device->driver_data = NULL; + err_clear_per_cpu: per_cpu(processors, pr->id) = NULL; + err_clear_driver_data: + device->driver_data = NULL; + free_cpumask_var(pr->throttling.shared_cpu_map); err_free_pr: kfree(pr); return result; } #ifdef CONFIG_ACPI_HOTPLUG_CPU -/* -------------------------------------------------------------------------- - Removal - -------------------------------------------------------------------------- */ - -static void acpi_processor_remove(struct acpi_device *device) +/* Removal */ +static void acpi_processor_post_eject(struct acpi_device *device) { struct acpi_processor *pr; @@ -465,18 +497,18 @@ static void acpi_processor_remove(struct acpi_device *device) device_release_driver(pr->dev); acpi_unbind_one(pr->dev); - /* Clean up. */ - per_cpu(processor_device_array, pr->id) = NULL; - per_cpu(processors, pr->id) = NULL; - cpu_maps_update_begin(); - cpu_hotplug_begin(); + cpus_write_lock(); /* Remove the CPU. */ arch_unregister_cpu(pr->id); acpi_unmap_cpu(pr->id); - cpu_hotplug_done(); + /* Clean up. */ + per_cpu(processor_device_array, pr->id) = NULL; + per_cpu(processors, pr->id) = NULL; + + cpus_write_unlock(); cpu_maps_update_done(); try_offline_node(cpu_to_node(pr->id)); @@ -487,54 +519,110 @@ static void acpi_processor_remove(struct acpi_device *device) } #endif /* CONFIG_ACPI_HOTPLUG_CPU */ -#ifdef CONFIG_X86 -static bool acpi_hwp_native_thermal_lvt_set; -static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle, - u32 lvl, - void *context, - void **rv) +#ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC +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 = {}; + 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, METHOD_NAME__UID, + NULL, &tmp); + if (ACPI_FAILURE(status)) + return false; + acpi_id = tmp; + break; + default: + return false; + } + + if (xen_initial_domain()) + /* + * When running as a Xen dom0 the number of processors Linux + * sees can be different from the real number of processors on + * the system, and we still need to execute _PDC or _OSC for + * all of them. + */ + return xen_processor_present(acpi_id); + + type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0; + cpuid = acpi_get_cpuid(handle, type, acpi_id); + + return !invalid_logical_cpuid(cpuid); +} + +/* vendor specific UUID indicating an Intel platform */ +static u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953"; + +static acpi_status __init acpi_processor_osc(acpi_handle handle, u32 lvl, + void *context, void **rv) { - u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953"; - u32 capbuf[2]; + u32 capbuf[2] = {}; struct acpi_osc_context osc_context = { .uuid_str = sb_uuid_str, .rev = 1, .cap.length = 8, .cap.pointer = capbuf, }; + acpi_status status; - if (acpi_hwp_native_thermal_lvt_set) - return AE_CTRL_TERMINATE; + if (!processor_physically_present(handle)) + return AE_OK; - capbuf[0] = 0x0000; - capbuf[1] = 0x1000; /* set bit 12 */ + arch_acpi_set_proc_cap_bits(&capbuf[OSC_SUPPORT_DWORD]); - if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) { - if (osc_context.ret.pointer && osc_context.ret.length > 1) { - u32 *capbuf_ret = osc_context.ret.pointer; + status = acpi_run_osc(handle, &osc_context); + if (ACPI_FAILURE(status)) + return status; - if (capbuf_ret[1] & 0x1000) { - acpi_handle_info(handle, - "_OSC native thermal LVT Acked\n"); - acpi_hwp_native_thermal_lvt_set = true; - } - } - kfree(osc_context.ret.pointer); - } + kfree(osc_context.ret.pointer); return AE_OK; } -void __init acpi_early_processor_osc(void) +static bool __init acpi_early_processor_osc(void) +{ + acpi_status status; + + acpi_proc_quirk_mwait_check(); + + status = acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, + ACPI_UINT32_MAX, acpi_processor_osc, NULL, + NULL, NULL); + if (ACPI_FAILURE(status)) + return false; + + status = acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_osc, + NULL, NULL); + if (ACPI_FAILURE(status)) + return false; + + return true; +} + +void __init acpi_early_processor_control_setup(void) { - if (boot_cpu_has(X86_FEATURE_HWP)) { - acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, - ACPI_UINT32_MAX, - acpi_hwp_native_thermal_lvt_osc, - NULL, NULL, NULL); - acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, - acpi_hwp_native_thermal_lvt_osc, - NULL, NULL); + if (acpi_early_processor_osc()) { + pr_debug("_OSC evaluated successfully for all CPUs\n"); + } else { + pr_debug("_OSC evaluation for CPUs failed, trying _PDC\n"); + acpi_early_processor_set_pdc(); } } #endif @@ -555,7 +643,7 @@ static struct acpi_scan_handler processor_handler = { .ids = processor_device_ids, .attach = acpi_processor_add, #ifdef CONFIG_ACPI_HOTPLUG_CPU - .detach = acpi_processor_remove, + .post_eject = acpi_processor_post_eject, #endif .hotplug = { .enabled = true, @@ -642,7 +730,7 @@ static acpi_status __init acpi_processor_ids_walk(acpi_handle handle, status = acpi_get_type(handle, &acpi_type); if (ACPI_FAILURE(status)) - return false; + return status; switch (acpi_type) { case ACPI_TYPE_PROCESSOR: @@ -662,15 +750,16 @@ static acpi_status __init acpi_processor_ids_walk(acpi_handle handle, } processor_validated_ids_update(uid); - return true; + return AE_OK; err: + /* Exit on error, but don't abort the namespace walk */ acpi_handle_info(handle, "Invalid processor object\n"); - return false; + return AE_OK; } -void __init acpi_processor_check_duplicates(void) +static void __init acpi_processor_check_duplicates(void) { /* check the correctness for all processors in ACPI namespace */ acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, @@ -701,4 +790,209 @@ void __init acpi_processor_init(void) acpi_processor_check_duplicates(); acpi_scan_add_handler_with_hotplug(&processor_handler, "processor"); acpi_scan_add_handler(&processor_container_handler); + acpi_pcc_cpufreq_init(); +} + +#ifdef CONFIG_ACPI_PROCESSOR_CSTATE +/** + * acpi_processor_claim_cst_control - Request _CST control from the platform. + */ +bool acpi_processor_claim_cst_control(void) +{ + static bool cst_control_claimed; + acpi_status status; + + if (!acpi_gbl_FADT.cst_control || cst_control_claimed) + return true; + + status = acpi_os_write_port(acpi_gbl_FADT.smi_command, + acpi_gbl_FADT.cst_control, 8); + if (ACPI_FAILURE(status)) { + pr_warn("ACPI: Failed to claim processor _CST control\n"); + return false; + } + + cst_control_claimed = true; + return true; +} +EXPORT_SYMBOL_NS_GPL(acpi_processor_claim_cst_control, "ACPI_PROCESSOR_IDLE"); + +/** + * acpi_processor_evaluate_cst - Evaluate the processor _CST control method. + * @handle: ACPI handle of the processor object containing the _CST. + * @cpu: The numeric ID of the target CPU. + * @info: Object write the C-states information into. + * + * Extract the C-state information for the given CPU from the output of the _CST + * control method under the corresponding ACPI processor object (or processor + * device object) and populate @info with it. + * + * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke + * acpi_processor_ffh_cstate_probe() to verify them and update the + * cpu_cstate_entry data for @cpu. + */ +int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu, + struct acpi_processor_power *info) +{ + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *cst; + acpi_status status; + u64 count; + int last_index = 0; + int i, ret = 0; + + status = acpi_evaluate_object(handle, "_CST", NULL, &buffer); + if (ACPI_FAILURE(status)) { + acpi_handle_debug(handle, "No _CST\n"); + return -ENODEV; + } + + cst = buffer.pointer; + + /* There must be at least 2 elements. */ + if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) { + acpi_handle_warn(handle, "Invalid _CST output\n"); + ret = -EFAULT; + goto end; + } + + count = cst->package.elements[0].integer.value; + + /* Validate the number of C-states. */ + if (count < 1 || count != cst->package.count - 1) { + acpi_handle_warn(handle, "Inconsistent _CST data\n"); + ret = -EFAULT; + goto end; + } + + for (i = 1; i <= count; i++) { + union acpi_object *element; + union acpi_object *obj; + struct acpi_power_register *reg; + struct acpi_processor_cx cx; + + /* + * If there is not enough space for all C-states, skip the + * excess ones and log a warning. + */ + if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) { + acpi_handle_warn(handle, + "No room for more idle states (limit: %d)\n", + ACPI_PROCESSOR_MAX_POWER - 1); + break; + } + + memset(&cx, 0, sizeof(cx)); + + element = &cst->package.elements[i]; + if (element->type != ACPI_TYPE_PACKAGE) { + acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n", + i, element->type); + continue; + } + + if (element->package.count != 4) { + acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n", + i, element->package.count); + continue; + } + + obj = &element->package.elements[0]; + + if (obj->type != ACPI_TYPE_BUFFER) { + acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n", + i, obj->type); + continue; + } + + reg = (struct acpi_power_register *)obj->buffer.pointer; + + obj = &element->package.elements[1]; + if (obj->type != ACPI_TYPE_INTEGER) { + acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n", + i, obj->type); + continue; + } + + cx.type = obj->integer.value; + /* + * There are known cases in which the _CST output does not + * contain C1, so if the type of the first state found is not + * C1, leave an empty slot for C1 to be filled in later. + */ + if (i == 1 && cx.type != ACPI_STATE_C1) + last_index = 1; + + cx.address = reg->address; + cx.index = last_index + 1; + + if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { + if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) { + /* + * In the majority of cases _CST describes C1 as + * a FIXED_HARDWARE C-state, but if the command + * line forbids using MWAIT, use CSTATE_HALT for + * C1 regardless. + */ + if (cx.type == ACPI_STATE_C1 && + boot_option_idle_override == IDLE_NOMWAIT) { + cx.entry_method = ACPI_CSTATE_HALT; + snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); + } else { + cx.entry_method = ACPI_CSTATE_FFH; + } + } else if (cx.type == ACPI_STATE_C1) { + /* + * In the special case of C1, FIXED_HARDWARE can + * be handled by executing the HLT instruction. + */ + cx.entry_method = ACPI_CSTATE_HALT; + snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); + } else { + acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n", + i); + continue; + } + } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) { + cx.entry_method = ACPI_CSTATE_SYSTEMIO; + snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x", + cx.address); + } else { + acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n", + i, reg->space_id); + continue; + } + + if (cx.type == ACPI_STATE_C1) + cx.valid = 1; + + obj = &element->package.elements[2]; + if (obj->type != ACPI_TYPE_INTEGER) { + acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n", + i, obj->type); + continue; + } + + cx.latency = obj->integer.value; + + obj = &element->package.elements[3]; + if (obj->type != ACPI_TYPE_INTEGER) { + acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n", + i, obj->type); + continue; + } + + memcpy(&info->states[++last_index], &cx, sizeof(cx)); + } + + acpi_handle_debug(handle, "Found %d idle states\n", last_index); + + info->count = last_index; + +end: + kfree(buffer.pointer); + + return ret; } +EXPORT_SYMBOL_NS_GPL(acpi_processor_evaluate_cst, "ACPI_PROCESSOR_IDLE"); +#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */ |