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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * acpi-cpufreq.c - ACPI Processor P-States Driver4 *5 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>6 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>7 *  Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>8 *  Copyright (C) 2006       Denis Sadykov <denis.m.sadykov@intel.com>9 */10 11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt12 13#include <linux/kernel.h>14#include <linux/module.h>15#include <linux/init.h>16#include <linux/smp.h>17#include <linux/sched.h>18#include <linux/cpufreq.h>19#include <linux/compiler.h>20#include <linux/dmi.h>21#include <linux/slab.h>22#include <linux/string_helpers.h>23#include <linux/platform_device.h>24 25#include <linux/acpi.h>26#include <linux/io.h>27#include <linux/delay.h>28#include <linux/uaccess.h>29 30#include <acpi/processor.h>31#include <acpi/cppc_acpi.h>32 33#include <asm/msr.h>34#include <asm/processor.h>35#include <asm/cpufeature.h>36#include <asm/cpu_device_id.h>37 38MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");39MODULE_DESCRIPTION("ACPI Processor P-States Driver");40MODULE_LICENSE("GPL");41 42enum {43	UNDEFINED_CAPABLE = 0,44	SYSTEM_INTEL_MSR_CAPABLE,45	SYSTEM_AMD_MSR_CAPABLE,46	SYSTEM_IO_CAPABLE,47};48 49#define INTEL_MSR_RANGE		(0xffff)50#define AMD_MSR_RANGE		(0x7)51#define HYGON_MSR_RANGE		(0x7)52 53struct acpi_cpufreq_data {54	unsigned int resume;55	unsigned int cpu_feature;56	unsigned int acpi_perf_cpu;57	cpumask_var_t freqdomain_cpus;58	void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);59	u32 (*cpu_freq_read)(struct acpi_pct_register *reg);60};61 62/* acpi_perf_data is a pointer to percpu data. */63static struct acpi_processor_performance __percpu *acpi_perf_data;64 65static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)66{67	return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);68}69 70static struct cpufreq_driver acpi_cpufreq_driver;71 72static unsigned int acpi_pstate_strict;73 74static bool boost_state(unsigned int cpu)75{76	u32 lo, hi;77	u64 msr;78 79	switch (boot_cpu_data.x86_vendor) {80	case X86_VENDOR_INTEL:81	case X86_VENDOR_CENTAUR:82	case X86_VENDOR_ZHAOXIN:83		rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);84		msr = lo | ((u64)hi << 32);85		return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);86	case X86_VENDOR_HYGON:87	case X86_VENDOR_AMD:88		rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);89		msr = lo | ((u64)hi << 32);90		return !(msr & MSR_K7_HWCR_CPB_DIS);91	}92	return false;93}94 95static int boost_set_msr(bool enable)96{97	u32 msr_addr;98	u64 msr_mask, val;99 100	switch (boot_cpu_data.x86_vendor) {101	case X86_VENDOR_INTEL:102	case X86_VENDOR_CENTAUR:103	case X86_VENDOR_ZHAOXIN:104		msr_addr = MSR_IA32_MISC_ENABLE;105		msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;106		break;107	case X86_VENDOR_HYGON:108	case X86_VENDOR_AMD:109		msr_addr = MSR_K7_HWCR;110		msr_mask = MSR_K7_HWCR_CPB_DIS;111		break;112	default:113		return -EINVAL;114	}115 116	rdmsrl(msr_addr, val);117 118	if (enable)119		val &= ~msr_mask;120	else121		val |= msr_mask;122 123	wrmsrl(msr_addr, val);124	return 0;125}126 127static void boost_set_msr_each(void *p_en)128{129	bool enable = (bool) p_en;130 131	boost_set_msr(enable);132}133 134static int set_boost(struct cpufreq_policy *policy, int val)135{136	on_each_cpu_mask(policy->cpus, boost_set_msr_each,137			 (void *)(long)val, 1);138	pr_debug("CPU %*pbl: Core Boosting %s.\n",139		 cpumask_pr_args(policy->cpus), str_enabled_disabled(val));140 141	return 0;142}143 144static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)145{146	struct acpi_cpufreq_data *data = policy->driver_data;147 148	if (unlikely(!data))149		return -ENODEV;150 151	return cpufreq_show_cpus(data->freqdomain_cpus, buf);152}153 154cpufreq_freq_attr_ro(freqdomain_cpus);155 156#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB157static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,158			 size_t count)159{160	int ret;161	unsigned int val = 0;162 163	if (!acpi_cpufreq_driver.set_boost)164		return -EINVAL;165 166	ret = kstrtouint(buf, 10, &val);167	if (ret || val > 1)168		return -EINVAL;169 170	cpus_read_lock();171	set_boost(policy, val);172	cpus_read_unlock();173 174	return count;175}176 177static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)178{179	return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);180}181 182cpufreq_freq_attr_rw(cpb);183#endif184 185static int check_est_cpu(unsigned int cpuid)186{187	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);188 189	return cpu_has(cpu, X86_FEATURE_EST);190}191 192static int check_amd_hwpstate_cpu(unsigned int cpuid)193{194	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);195 196	return cpu_has(cpu, X86_FEATURE_HW_PSTATE);197}198 199static unsigned extract_io(struct cpufreq_policy *policy, u32 value)200{201	struct acpi_cpufreq_data *data = policy->driver_data;202	struct acpi_processor_performance *perf;203	int i;204 205	perf = to_perf_data(data);206 207	for (i = 0; i < perf->state_count; i++) {208		if (value == perf->states[i].status)209			return policy->freq_table[i].frequency;210	}211	return 0;212}213 214static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)215{216	struct acpi_cpufreq_data *data = policy->driver_data;217	struct cpufreq_frequency_table *pos;218	struct acpi_processor_performance *perf;219 220	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)221		msr &= AMD_MSR_RANGE;222	else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)223		msr &= HYGON_MSR_RANGE;224	else225		msr &= INTEL_MSR_RANGE;226 227	perf = to_perf_data(data);228 229	cpufreq_for_each_entry(pos, policy->freq_table)230		if (msr == perf->states[pos->driver_data].status)231			return pos->frequency;232	return policy->freq_table[0].frequency;233}234 235static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)236{237	struct acpi_cpufreq_data *data = policy->driver_data;238 239	switch (data->cpu_feature) {240	case SYSTEM_INTEL_MSR_CAPABLE:241	case SYSTEM_AMD_MSR_CAPABLE:242		return extract_msr(policy, val);243	case SYSTEM_IO_CAPABLE:244		return extract_io(policy, val);245	default:246		return 0;247	}248}249 250static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)251{252	u32 val, dummy __always_unused;253 254	rdmsr(MSR_IA32_PERF_CTL, val, dummy);255	return val;256}257 258static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)259{260	u32 lo, hi;261 262	rdmsr(MSR_IA32_PERF_CTL, lo, hi);263	lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);264	wrmsr(MSR_IA32_PERF_CTL, lo, hi);265}266 267static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)268{269	u32 val, dummy __always_unused;270 271	rdmsr(MSR_AMD_PERF_CTL, val, dummy);272	return val;273}274 275static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)276{277	wrmsr(MSR_AMD_PERF_CTL, val, 0);278}279 280static u32 cpu_freq_read_io(struct acpi_pct_register *reg)281{282	u32 val;283 284	acpi_os_read_port(reg->address, &val, reg->bit_width);285	return val;286}287 288static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)289{290	acpi_os_write_port(reg->address, val, reg->bit_width);291}292 293struct drv_cmd {294	struct acpi_pct_register *reg;295	u32 val;296	union {297		void (*write)(struct acpi_pct_register *reg, u32 val);298		u32 (*read)(struct acpi_pct_register *reg);299	} func;300};301 302/* Called via smp_call_function_single(), on the target CPU */303static void do_drv_read(void *_cmd)304{305	struct drv_cmd *cmd = _cmd;306 307	cmd->val = cmd->func.read(cmd->reg);308}309 310static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)311{312	struct acpi_processor_performance *perf = to_perf_data(data);313	struct drv_cmd cmd = {314		.reg = &perf->control_register,315		.func.read = data->cpu_freq_read,316	};317	int err;318 319	err = smp_call_function_any(mask, do_drv_read, &cmd, 1);320	WARN_ON_ONCE(err);	/* smp_call_function_any() was buggy? */321	return cmd.val;322}323 324/* Called via smp_call_function_many(), on the target CPUs */325static void do_drv_write(void *_cmd)326{327	struct drv_cmd *cmd = _cmd;328 329	cmd->func.write(cmd->reg, cmd->val);330}331 332static void drv_write(struct acpi_cpufreq_data *data,333		      const struct cpumask *mask, u32 val)334{335	struct acpi_processor_performance *perf = to_perf_data(data);336	struct drv_cmd cmd = {337		.reg = &perf->control_register,338		.val = val,339		.func.write = data->cpu_freq_write,340	};341	int this_cpu;342 343	this_cpu = get_cpu();344	if (cpumask_test_cpu(this_cpu, mask))345		do_drv_write(&cmd);346 347	smp_call_function_many(mask, do_drv_write, &cmd, 1);348	put_cpu();349}350 351static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)352{353	u32 val;354 355	if (unlikely(cpumask_empty(mask)))356		return 0;357 358	val = drv_read(data, mask);359 360	pr_debug("%s = %u\n", __func__, val);361 362	return val;363}364 365static unsigned int get_cur_freq_on_cpu(unsigned int cpu)366{367	struct acpi_cpufreq_data *data;368	struct cpufreq_policy *policy;369	unsigned int freq;370	unsigned int cached_freq;371 372	pr_debug("%s (%d)\n", __func__, cpu);373 374	policy = cpufreq_cpu_get_raw(cpu);375	if (unlikely(!policy))376		return 0;377 378	data = policy->driver_data;379	if (unlikely(!data || !policy->freq_table))380		return 0;381 382	cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;383	freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));384	if (freq != cached_freq) {385		/*386		 * The dreaded BIOS frequency change behind our back.387		 * Force set the frequency on next target call.388		 */389		data->resume = 1;390	}391 392	pr_debug("cur freq = %u\n", freq);393 394	return freq;395}396 397static unsigned int check_freqs(struct cpufreq_policy *policy,398				const struct cpumask *mask, unsigned int freq)399{400	struct acpi_cpufreq_data *data = policy->driver_data;401	unsigned int cur_freq;402	unsigned int i;403 404	for (i = 0; i < 100; i++) {405		cur_freq = extract_freq(policy, get_cur_val(mask, data));406		if (cur_freq == freq)407			return 1;408		udelay(10);409	}410	return 0;411}412 413static int acpi_cpufreq_target(struct cpufreq_policy *policy,414			       unsigned int index)415{416	struct acpi_cpufreq_data *data = policy->driver_data;417	struct acpi_processor_performance *perf;418	const struct cpumask *mask;419	unsigned int next_perf_state = 0; /* Index into perf table */420	int result = 0;421 422	if (unlikely(!data)) {423		return -ENODEV;424	}425 426	perf = to_perf_data(data);427	next_perf_state = policy->freq_table[index].driver_data;428	if (perf->state == next_perf_state) {429		if (unlikely(data->resume)) {430			pr_debug("Called after resume, resetting to P%d\n",431				next_perf_state);432			data->resume = 0;433		} else {434			pr_debug("Already at target state (P%d)\n",435				next_perf_state);436			return 0;437		}438	}439 440	/*441	 * The core won't allow CPUs to go away until the governor has been442	 * stopped, so we can rely on the stability of policy->cpus.443	 */444	mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?445		cpumask_of(policy->cpu) : policy->cpus;446 447	drv_write(data, mask, perf->states[next_perf_state].control);448 449	if (acpi_pstate_strict) {450		if (!check_freqs(policy, mask,451				 policy->freq_table[index].frequency)) {452			pr_debug("%s (%d)\n", __func__, policy->cpu);453			result = -EAGAIN;454		}455	}456 457	if (!result)458		perf->state = next_perf_state;459 460	return result;461}462 463static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,464					     unsigned int target_freq)465{466	struct acpi_cpufreq_data *data = policy->driver_data;467	struct acpi_processor_performance *perf;468	struct cpufreq_frequency_table *entry;469	unsigned int next_perf_state, next_freq, index;470 471	/*472	 * Find the closest frequency above target_freq.473	 */474	if (policy->cached_target_freq == target_freq)475		index = policy->cached_resolved_idx;476	else477		index = cpufreq_table_find_index_dl(policy, target_freq,478						    false);479 480	entry = &policy->freq_table[index];481	next_freq = entry->frequency;482	next_perf_state = entry->driver_data;483 484	perf = to_perf_data(data);485	if (perf->state == next_perf_state) {486		if (unlikely(data->resume))487			data->resume = 0;488		else489			return next_freq;490	}491 492	data->cpu_freq_write(&perf->control_register,493			     perf->states[next_perf_state].control);494	perf->state = next_perf_state;495	return next_freq;496}497 498static unsigned long499acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)500{501	struct acpi_processor_performance *perf;502 503	perf = to_perf_data(data);504	if (cpu_khz) {505		/* search the closest match to cpu_khz */506		unsigned int i;507		unsigned long freq;508		unsigned long freqn = perf->states[0].core_frequency * 1000;509 510		for (i = 0; i < (perf->state_count-1); i++) {511			freq = freqn;512			freqn = perf->states[i+1].core_frequency * 1000;513			if ((2 * cpu_khz) > (freqn + freq)) {514				perf->state = i;515				return freq;516			}517		}518		perf->state = perf->state_count-1;519		return freqn;520	} else {521		/* assume CPU is at P0... */522		perf->state = 0;523		return perf->states[0].core_frequency * 1000;524	}525}526 527static void free_acpi_perf_data(void)528{529	unsigned int i;530 531	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */532	for_each_possible_cpu(i)533		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)534				 ->shared_cpu_map);535	free_percpu(acpi_perf_data);536}537 538static int cpufreq_boost_down_prep(unsigned int cpu)539{540	/*541	 * Clear the boost-disable bit on the CPU_DOWN path so that542	 * this cpu cannot block the remaining ones from boosting.543	 */544	return boost_set_msr(1);545}546 547/*548 * acpi_cpufreq_early_init - initialize ACPI P-States library549 *550 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)551 * in order to determine correct frequency and voltage pairings. We can552 * do _PDC and _PSD and find out the processor dependency for the553 * actual init that will happen later...554 */555static int __init acpi_cpufreq_early_init(void)556{557	unsigned int i;558	pr_debug("%s\n", __func__);559 560	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);561	if (!acpi_perf_data) {562		pr_debug("Memory allocation error for acpi_perf_data.\n");563		return -ENOMEM;564	}565	for_each_possible_cpu(i) {566		if (!zalloc_cpumask_var_node(567			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,568			GFP_KERNEL, cpu_to_node(i))) {569 570			/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */571			free_acpi_perf_data();572			return -ENOMEM;573		}574	}575 576	/* Do initialization in ACPI core */577	acpi_processor_preregister_performance(acpi_perf_data);578	return 0;579}580 581#ifdef CONFIG_SMP582/*583 * Some BIOSes do SW_ANY coordination internally, either set it up in hw584 * or do it in BIOS firmware and won't inform about it to OS. If not585 * detected, this has a side effect of making CPU run at a different speed586 * than OS intended it to run at. Detect it and handle it cleanly.587 */588static int bios_with_sw_any_bug;589 590static int sw_any_bug_found(const struct dmi_system_id *d)591{592	bios_with_sw_any_bug = 1;593	return 0;594}595 596static const struct dmi_system_id sw_any_bug_dmi_table[] = {597	{598		.callback = sw_any_bug_found,599		.ident = "Supermicro Server X6DLP",600		.matches = {601			DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),602			DMI_MATCH(DMI_BIOS_VERSION, "080010"),603			DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),604		},605	},606	{ }607};608 609static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)610{611	/* Intel Xeon Processor 7100 Series Specification Update612	 * https://www.intel.com/Assets/PDF/specupdate/314554.pdf613	 * AL30: A Machine Check Exception (MCE) Occurring during an614	 * Enhanced Intel SpeedStep Technology Ratio Change May Cause615	 * Both Processor Cores to Lock Up. */616	if (c->x86_vendor == X86_VENDOR_INTEL) {617		if ((c->x86 == 15) &&618		    (c->x86_model == 6) &&619		    (c->x86_stepping == 8)) {620			pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");621			return -ENODEV;622		    }623		}624	return 0;625}626#endif627 628#ifdef CONFIG_ACPI_CPPC_LIB629static u64 get_max_boost_ratio(unsigned int cpu)630{631	struct cppc_perf_caps perf_caps;632	u64 highest_perf, nominal_perf;633	int ret;634 635	if (acpi_pstate_strict)636		return 0;637 638	ret = cppc_get_perf_caps(cpu, &perf_caps);639	if (ret) {640		pr_debug("CPU%d: Unable to get performance capabilities (%d)\n",641			 cpu, ret);642		return 0;643	}644 645	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {646		ret = amd_get_boost_ratio_numerator(cpu, &highest_perf);647		if (ret) {648			pr_debug("CPU%d: Unable to get boost ratio numerator (%d)\n",649				 cpu, ret);650			return 0;651		}652	} else {653		highest_perf = perf_caps.highest_perf;654	}655 656	nominal_perf = perf_caps.nominal_perf;657 658	if (!highest_perf || !nominal_perf) {659		pr_debug("CPU%d: highest or nominal performance missing\n", cpu);660		return 0;661	}662 663	if (highest_perf < nominal_perf) {664		pr_debug("CPU%d: nominal performance above highest\n", cpu);665		return 0;666	}667 668	return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf);669}670#else671static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; }672#endif673 674static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)675{676	struct cpufreq_frequency_table *freq_table;677	struct acpi_processor_performance *perf;678	struct acpi_cpufreq_data *data;679	unsigned int cpu = policy->cpu;680	struct cpuinfo_x86 *c = &cpu_data(cpu);681	unsigned int valid_states = 0;682	unsigned int result = 0;683	u64 max_boost_ratio;684	unsigned int i;685#ifdef CONFIG_SMP686	static int blacklisted;687#endif688 689	pr_debug("%s\n", __func__);690 691#ifdef CONFIG_SMP692	if (blacklisted)693		return blacklisted;694	blacklisted = acpi_cpufreq_blacklist(c);695	if (blacklisted)696		return blacklisted;697#endif698 699	data = kzalloc(sizeof(*data), GFP_KERNEL);700	if (!data)701		return -ENOMEM;702 703	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {704		result = -ENOMEM;705		goto err_free;706	}707 708	perf = per_cpu_ptr(acpi_perf_data, cpu);709	data->acpi_perf_cpu = cpu;710	policy->driver_data = data;711 712	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))713		acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;714 715	result = acpi_processor_register_performance(perf, cpu);716	if (result)717		goto err_free_mask;718 719	policy->shared_type = perf->shared_type;720 721	/*722	 * Will let policy->cpus know about dependency only when software723	 * coordination is required.724	 */725	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||726	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {727		cpumask_copy(policy->cpus, perf->shared_cpu_map);728	}729	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);730 731#ifdef CONFIG_SMP732	dmi_check_system(sw_any_bug_dmi_table);733	if (bios_with_sw_any_bug && !policy_is_shared(policy)) {734		policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;735		cpumask_copy(policy->cpus, topology_core_cpumask(cpu));736	}737 738	if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&739	    !acpi_pstate_strict) {740		cpumask_clear(policy->cpus);741		cpumask_set_cpu(cpu, policy->cpus);742		cpumask_copy(data->freqdomain_cpus,743			     topology_sibling_cpumask(cpu));744		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;745		pr_info_once("overriding BIOS provided _PSD data\n");746	}747#endif748 749	/* capability check */750	if (perf->state_count <= 1) {751		pr_debug("No P-States\n");752		result = -ENODEV;753		goto err_unreg;754	}755 756	if (perf->control_register.space_id != perf->status_register.space_id) {757		result = -ENODEV;758		goto err_unreg;759	}760 761	switch (perf->control_register.space_id) {762	case ACPI_ADR_SPACE_SYSTEM_IO:763		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&764		    boot_cpu_data.x86 == 0xf) {765			pr_debug("AMD K8 systems must use native drivers.\n");766			result = -ENODEV;767			goto err_unreg;768		}769		pr_debug("SYSTEM IO addr space\n");770		data->cpu_feature = SYSTEM_IO_CAPABLE;771		data->cpu_freq_read = cpu_freq_read_io;772		data->cpu_freq_write = cpu_freq_write_io;773		break;774	case ACPI_ADR_SPACE_FIXED_HARDWARE:775		pr_debug("HARDWARE addr space\n");776		if (check_est_cpu(cpu)) {777			data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;778			data->cpu_freq_read = cpu_freq_read_intel;779			data->cpu_freq_write = cpu_freq_write_intel;780			break;781		}782		if (check_amd_hwpstate_cpu(cpu)) {783			data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;784			data->cpu_freq_read = cpu_freq_read_amd;785			data->cpu_freq_write = cpu_freq_write_amd;786			break;787		}788		result = -ENODEV;789		goto err_unreg;790	default:791		pr_debug("Unknown addr space %d\n",792			(u32) (perf->control_register.space_id));793		result = -ENODEV;794		goto err_unreg;795	}796 797	freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),798			     GFP_KERNEL);799	if (!freq_table) {800		result = -ENOMEM;801		goto err_unreg;802	}803 804	/* detect transition latency */805	policy->cpuinfo.transition_latency = 0;806	for (i = 0; i < perf->state_count; i++) {807		if ((perf->states[i].transition_latency * 1000) >808		    policy->cpuinfo.transition_latency)809			policy->cpuinfo.transition_latency =810			    perf->states[i].transition_latency * 1000;811	}812 813	/* Check for high latency (>20uS) from buggy BIOSes, like on T42 */814	if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&815	    policy->cpuinfo.transition_latency > 20 * 1000) {816		policy->cpuinfo.transition_latency = 20 * 1000;817		pr_info_once("P-state transition latency capped at 20 uS\n");818	}819 820	/* table init */821	for (i = 0; i < perf->state_count; i++) {822		if (i > 0 && perf->states[i].core_frequency >=823		    freq_table[valid_states-1].frequency / 1000)824			continue;825 826		freq_table[valid_states].driver_data = i;827		freq_table[valid_states].frequency =828		    perf->states[i].core_frequency * 1000;829		valid_states++;830	}831	freq_table[valid_states].frequency = CPUFREQ_TABLE_END;832 833	max_boost_ratio = get_max_boost_ratio(cpu);834	if (max_boost_ratio) {835		unsigned int freq = freq_table[0].frequency;836 837		/*838		 * Because the loop above sorts the freq_table entries in the839		 * descending order, freq is the maximum frequency in the table.840		 * Assume that it corresponds to the CPPC nominal frequency and841		 * use it to set cpuinfo.max_freq.842		 */843		policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT;844	} else {845		/*846		 * If the maximum "boost" frequency is unknown, ask the arch847		 * scale-invariance code to use the "nominal" performance for848		 * CPU utilization scaling so as to prevent the schedutil849		 * governor from selecting inadequate CPU frequencies.850		 */851		arch_set_max_freq_ratio(true);852	}853 854	policy->freq_table = freq_table;855	perf->state = 0;856 857	switch (perf->control_register.space_id) {858	case ACPI_ADR_SPACE_SYSTEM_IO:859		/*860		 * The core will not set policy->cur, because861		 * cpufreq_driver->get is NULL, so we need to set it here.862		 * However, we have to guess it, because the current speed is863		 * unknown and not detectable via IO ports.864		 */865		policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);866		break;867	case ACPI_ADR_SPACE_FIXED_HARDWARE:868		acpi_cpufreq_driver.get = get_cur_freq_on_cpu;869		break;870	default:871		break;872	}873 874	/* notify BIOS that we exist */875	acpi_processor_notify_smm(THIS_MODULE);876 877	pr_debug("CPU%u - ACPI performance management activated.\n", cpu);878	for (i = 0; i < perf->state_count; i++)879		pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",880			(i == perf->state ? '*' : ' '), i,881			(u32) perf->states[i].core_frequency,882			(u32) perf->states[i].power,883			(u32) perf->states[i].transition_latency);884 885	/*886	 * the first call to ->target() should result in us actually887	 * writing something to the appropriate registers.888	 */889	data->resume = 1;890 891	policy->fast_switch_possible = !acpi_pstate_strict &&892		!(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);893 894	if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency)895		pr_warn(FW_WARN "P-state 0 is not max freq\n");896 897	if (acpi_cpufreq_driver.set_boost) {898		set_boost(policy, acpi_cpufreq_driver.boost_enabled);899		policy->boost_enabled = acpi_cpufreq_driver.boost_enabled;900	}901 902	return result;903 904err_unreg:905	acpi_processor_unregister_performance(cpu);906err_free_mask:907	free_cpumask_var(data->freqdomain_cpus);908err_free:909	kfree(data);910	policy->driver_data = NULL;911 912	return result;913}914 915static void acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)916{917	struct acpi_cpufreq_data *data = policy->driver_data;918 919	pr_debug("%s\n", __func__);920 921	cpufreq_boost_down_prep(policy->cpu);922	policy->fast_switch_possible = false;923	policy->driver_data = NULL;924	acpi_processor_unregister_performance(data->acpi_perf_cpu);925	free_cpumask_var(data->freqdomain_cpus);926	kfree(policy->freq_table);927	kfree(data);928}929 930static int acpi_cpufreq_resume(struct cpufreq_policy *policy)931{932	struct acpi_cpufreq_data *data = policy->driver_data;933 934	pr_debug("%s\n", __func__);935 936	data->resume = 1;937 938	return 0;939}940 941static struct freq_attr *acpi_cpufreq_attr[] = {942	&cpufreq_freq_attr_scaling_available_freqs,943	&freqdomain_cpus,944#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB945	&cpb,946#endif947	NULL,948};949 950static struct cpufreq_driver acpi_cpufreq_driver = {951	.verify		= cpufreq_generic_frequency_table_verify,952	.target_index	= acpi_cpufreq_target,953	.fast_switch	= acpi_cpufreq_fast_switch,954	.bios_limit	= acpi_processor_get_bios_limit,955	.init		= acpi_cpufreq_cpu_init,956	.exit		= acpi_cpufreq_cpu_exit,957	.resume		= acpi_cpufreq_resume,958	.name		= "acpi-cpufreq",959	.attr		= acpi_cpufreq_attr,960};961 962static void __init acpi_cpufreq_boost_init(void)963{964	if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {965		pr_debug("Boost capabilities not present in the processor\n");966		return;967	}968 969	acpi_cpufreq_driver.set_boost = set_boost;970	acpi_cpufreq_driver.boost_enabled = boost_state(0);971}972 973static int __init acpi_cpufreq_probe(struct platform_device *pdev)974{975	int ret;976 977	if (acpi_disabled)978		return -ENODEV;979 980	/* don't keep reloading if cpufreq_driver exists */981	if (cpufreq_get_current_driver())982		return -ENODEV;983 984	pr_debug("%s\n", __func__);985 986	ret = acpi_cpufreq_early_init();987	if (ret)988		return ret;989 990#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB991	/* this is a sysfs file with a strange name and an even stranger992	 * semantic - per CPU instantiation, but system global effect.993	 * Lets enable it only on AMD CPUs for compatibility reasons and994	 * only if configured. This is considered legacy code, which995	 * will probably be removed at some point in the future.996	 */997	if (!check_amd_hwpstate_cpu(0)) {998		struct freq_attr **attr;999 1000		pr_debug("CPB unsupported, do not expose it\n");1001 1002		for (attr = acpi_cpufreq_attr; *attr; attr++)1003			if (*attr == &cpb) {1004				*attr = NULL;1005				break;1006			}1007	}1008#endif1009	acpi_cpufreq_boost_init();1010 1011	ret = cpufreq_register_driver(&acpi_cpufreq_driver);1012	if (ret) {1013		free_acpi_perf_data();1014	}1015	return ret;1016}1017 1018static void acpi_cpufreq_remove(struct platform_device *pdev)1019{1020	pr_debug("%s\n", __func__);1021 1022	cpufreq_unregister_driver(&acpi_cpufreq_driver);1023 1024	free_acpi_perf_data();1025}1026 1027static struct platform_driver acpi_cpufreq_platdrv = {1028	.driver = {1029		.name	= "acpi-cpufreq",1030	},1031	.remove_new	= acpi_cpufreq_remove,1032};1033 1034static int __init acpi_cpufreq_init(void)1035{1036	return platform_driver_probe(&acpi_cpufreq_platdrv, acpi_cpufreq_probe);1037}1038 1039static void __exit acpi_cpufreq_exit(void)1040{1041	platform_driver_unregister(&acpi_cpufreq_platdrv);1042}1043 1044module_param(acpi_pstate_strict, uint, 0644);1045MODULE_PARM_DESC(acpi_pstate_strict,1046	"value 0 or non-zero. non-zero -> strict ACPI checks are "1047	"performed during frequency changes.");1048 1049late_initcall(acpi_cpufreq_init);1050module_exit(acpi_cpufreq_exit);1051 1052MODULE_ALIAS("platform:acpi-cpufreq");1053