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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * CPPC (Collaborative Processor Performance Control) driver for4 * interfacing with the CPUfreq layer and governors. See5 * cppc_acpi.c for CPPC specific methods.6 *7 * (C) Copyright 2014, 2015 Linaro Ltd.8 * Author: Ashwin Chaugule <ashwin.chaugule@linaro.org>9 */10 11#define pr_fmt(fmt)	"CPPC Cpufreq:"	fmt12 13#include <linux/arch_topology.h>14#include <linux/kernel.h>15#include <linux/module.h>16#include <linux/delay.h>17#include <linux/cpu.h>18#include <linux/cpufreq.h>19#include <linux/irq_work.h>20#include <linux/kthread.h>21#include <linux/time.h>22#include <linux/vmalloc.h>23#include <uapi/linux/sched/types.h>24 25#include <linux/unaligned.h>26 27#include <acpi/cppc_acpi.h>28 29/*30 * This list contains information parsed from per CPU ACPI _CPC and _PSD31 * structures: e.g. the highest and lowest supported performance, capabilities,32 * desired performance, level requested etc. Depending on the share_type, not33 * all CPUs will have an entry in the list.34 */35static LIST_HEAD(cpu_data_list);36 37static bool boost_supported;38 39struct cppc_workaround_oem_info {40	char oem_id[ACPI_OEM_ID_SIZE + 1];41	char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1];42	u32 oem_revision;43};44 45static struct cppc_workaround_oem_info wa_info[] = {46	{47		.oem_id		= "HISI  ",48		.oem_table_id	= "HIP07   ",49		.oem_revision	= 0,50	}, {51		.oem_id		= "HISI  ",52		.oem_table_id	= "HIP08   ",53		.oem_revision	= 0,54	}55};56 57static struct cpufreq_driver cppc_cpufreq_driver;58 59static enum {60	FIE_UNSET = -1,61	FIE_ENABLED,62	FIE_DISABLED63} fie_disabled = FIE_UNSET;64 65#ifdef CONFIG_ACPI_CPPC_CPUFREQ_FIE66module_param(fie_disabled, int, 0444);67MODULE_PARM_DESC(fie_disabled, "Disable Frequency Invariance Engine (FIE)");68 69/* Frequency invariance support */70struct cppc_freq_invariance {71	int cpu;72	struct irq_work irq_work;73	struct kthread_work work;74	struct cppc_perf_fb_ctrs prev_perf_fb_ctrs;75	struct cppc_cpudata *cpu_data;76};77 78static DEFINE_PER_CPU(struct cppc_freq_invariance, cppc_freq_inv);79static struct kthread_worker *kworker_fie;80 81static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu);82static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data,83				 struct cppc_perf_fb_ctrs *fb_ctrs_t0,84				 struct cppc_perf_fb_ctrs *fb_ctrs_t1);85 86/**87 * cppc_scale_freq_workfn - CPPC arch_freq_scale updater for frequency invariance88 * @work: The work item.89 *90 * The CPPC driver register itself with the topology core to provide its own91 * implementation (cppc_scale_freq_tick()) of topology_scale_freq_tick() which92 * gets called by the scheduler on every tick.93 *94 * Note that the arch specific counters have higher priority than CPPC counters,95 * if available, though the CPPC driver doesn't need to have any special96 * handling for that.97 *98 * On an invocation of cppc_scale_freq_tick(), we schedule an irq work (since we99 * reach here from hard-irq context), which then schedules a normal work item100 * and cppc_scale_freq_workfn() updates the per_cpu arch_freq_scale variable101 * based on the counter updates since the last tick.102 */103static void cppc_scale_freq_workfn(struct kthread_work *work)104{105	struct cppc_freq_invariance *cppc_fi;106	struct cppc_perf_fb_ctrs fb_ctrs = {0};107	struct cppc_cpudata *cpu_data;108	unsigned long local_freq_scale;109	u64 perf;110 111	cppc_fi = container_of(work, struct cppc_freq_invariance, work);112	cpu_data = cppc_fi->cpu_data;113 114	if (cppc_get_perf_ctrs(cppc_fi->cpu, &fb_ctrs)) {115		pr_warn("%s: failed to read perf counters\n", __func__);116		return;117	}118 119	perf = cppc_perf_from_fbctrs(cpu_data, &cppc_fi->prev_perf_fb_ctrs,120				     &fb_ctrs);121	cppc_fi->prev_perf_fb_ctrs = fb_ctrs;122 123	perf <<= SCHED_CAPACITY_SHIFT;124	local_freq_scale = div64_u64(perf, cpu_data->perf_caps.highest_perf);125 126	/* This can happen due to counter's overflow */127	if (unlikely(local_freq_scale > 1024))128		local_freq_scale = 1024;129 130	per_cpu(arch_freq_scale, cppc_fi->cpu) = local_freq_scale;131}132 133static void cppc_irq_work(struct irq_work *irq_work)134{135	struct cppc_freq_invariance *cppc_fi;136 137	cppc_fi = container_of(irq_work, struct cppc_freq_invariance, irq_work);138	kthread_queue_work(kworker_fie, &cppc_fi->work);139}140 141static void cppc_scale_freq_tick(void)142{143	struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, smp_processor_id());144 145	/*146	 * cppc_get_perf_ctrs() can potentially sleep, call that from the right147	 * context.148	 */149	irq_work_queue(&cppc_fi->irq_work);150}151 152static struct scale_freq_data cppc_sftd = {153	.source = SCALE_FREQ_SOURCE_CPPC,154	.set_freq_scale = cppc_scale_freq_tick,155};156 157static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)158{159	struct cppc_freq_invariance *cppc_fi;160	int cpu, ret;161 162	if (fie_disabled)163		return;164 165	for_each_cpu(cpu, policy->cpus) {166		cppc_fi = &per_cpu(cppc_freq_inv, cpu);167		cppc_fi->cpu = cpu;168		cppc_fi->cpu_data = policy->driver_data;169		kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn);170		init_irq_work(&cppc_fi->irq_work, cppc_irq_work);171 172		ret = cppc_get_perf_ctrs(cpu, &cppc_fi->prev_perf_fb_ctrs);173		if (ret) {174			pr_warn("%s: failed to read perf counters for cpu:%d: %d\n",175				__func__, cpu, ret);176 177			/*178			 * Don't abort if the CPU was offline while the driver179			 * was getting registered.180			 */181			if (cpu_online(cpu))182				return;183		}184	}185 186	/* Register for freq-invariance */187	topology_set_scale_freq_source(&cppc_sftd, policy->cpus);188}189 190/*191 * We free all the resources on policy's removal and not on CPU removal as the192 * irq-work are per-cpu and the hotplug core takes care of flushing the pending193 * irq-works (hint: smpcfd_dying_cpu()) on CPU hotplug. Even if the kthread-work194 * fires on another CPU after the concerned CPU is removed, it won't harm.195 *196 * We just need to make sure to remove them all on policy->exit().197 */198static void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)199{200	struct cppc_freq_invariance *cppc_fi;201	int cpu;202 203	if (fie_disabled)204		return;205 206	/* policy->cpus will be empty here, use related_cpus instead */207	topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_CPPC, policy->related_cpus);208 209	for_each_cpu(cpu, policy->related_cpus) {210		cppc_fi = &per_cpu(cppc_freq_inv, cpu);211		irq_work_sync(&cppc_fi->irq_work);212		kthread_cancel_work_sync(&cppc_fi->work);213	}214}215 216static void __init cppc_freq_invariance_init(void)217{218	struct sched_attr attr = {219		.size		= sizeof(struct sched_attr),220		.sched_policy	= SCHED_DEADLINE,221		.sched_nice	= 0,222		.sched_priority	= 0,223		/*224		 * Fake (unused) bandwidth; workaround to "fix"225		 * priority inheritance.226		 */227		.sched_runtime	= NSEC_PER_MSEC,228		.sched_deadline = 10 * NSEC_PER_MSEC,229		.sched_period	= 10 * NSEC_PER_MSEC,230	};231	int ret;232 233	if (fie_disabled != FIE_ENABLED && fie_disabled != FIE_DISABLED) {234		fie_disabled = FIE_ENABLED;235		if (cppc_perf_ctrs_in_pcc()) {236			pr_info("FIE not enabled on systems with registers in PCC\n");237			fie_disabled = FIE_DISABLED;238		}239	}240 241	if (fie_disabled)242		return;243 244	kworker_fie = kthread_create_worker(0, "cppc_fie");245	if (IS_ERR(kworker_fie)) {246		pr_warn("%s: failed to create kworker_fie: %ld\n", __func__,247			PTR_ERR(kworker_fie));248		fie_disabled = FIE_DISABLED;249		return;250	}251 252	ret = sched_setattr_nocheck(kworker_fie->task, &attr);253	if (ret) {254		pr_warn("%s: failed to set SCHED_DEADLINE: %d\n", __func__,255			ret);256		kthread_destroy_worker(kworker_fie);257		fie_disabled = FIE_DISABLED;258	}259}260 261static void cppc_freq_invariance_exit(void)262{263	if (fie_disabled)264		return;265 266	kthread_destroy_worker(kworker_fie);267}268 269#else270static inline void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)271{272}273 274static inline void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)275{276}277 278static inline void cppc_freq_invariance_init(void)279{280}281 282static inline void cppc_freq_invariance_exit(void)283{284}285#endif /* CONFIG_ACPI_CPPC_CPUFREQ_FIE */286 287static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,288				   unsigned int target_freq,289				   unsigned int relation)290{291	struct cppc_cpudata *cpu_data = policy->driver_data;292	unsigned int cpu = policy->cpu;293	struct cpufreq_freqs freqs;294	int ret = 0;295 296	cpu_data->perf_ctrls.desired_perf =297			cppc_khz_to_perf(&cpu_data->perf_caps, target_freq);298	freqs.old = policy->cur;299	freqs.new = target_freq;300 301	cpufreq_freq_transition_begin(policy, &freqs);302	ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);303	cpufreq_freq_transition_end(policy, &freqs, ret != 0);304 305	if (ret)306		pr_debug("Failed to set target on CPU:%d. ret:%d\n",307			 cpu, ret);308 309	return ret;310}311 312static unsigned int cppc_cpufreq_fast_switch(struct cpufreq_policy *policy,313					      unsigned int target_freq)314{315	struct cppc_cpudata *cpu_data = policy->driver_data;316	unsigned int cpu = policy->cpu;317	u32 desired_perf;318	int ret;319 320	desired_perf = cppc_khz_to_perf(&cpu_data->perf_caps, target_freq);321	cpu_data->perf_ctrls.desired_perf = desired_perf;322	ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);323 324	if (ret) {325		pr_debug("Failed to set target on CPU:%d. ret:%d\n",326			 cpu, ret);327		return 0;328	}329 330	return target_freq;331}332 333static int cppc_verify_policy(struct cpufreq_policy_data *policy)334{335	cpufreq_verify_within_cpu_limits(policy);336	return 0;337}338 339/*340 * The PCC subspace describes the rate at which platform can accept commands341 * on the shared PCC channel (including READs which do not count towards freq342 * transition requests), so ideally we need to use the PCC values as a fallback343 * if we don't have a platform specific transition_delay_us344 */345#ifdef CONFIG_ARM64346#include <asm/cputype.h>347 348static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)349{350	unsigned long implementor = read_cpuid_implementor();351	unsigned long part_num = read_cpuid_part_number();352 353	switch (implementor) {354	case ARM_CPU_IMP_QCOM:355		switch (part_num) {356		case QCOM_CPU_PART_FALKOR_V1:357		case QCOM_CPU_PART_FALKOR:358			return 10000;359		}360	}361	return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;362}363#else364static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)365{366	return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;367}368#endif369 370#if defined(CONFIG_ARM64) && defined(CONFIG_ENERGY_MODEL)371 372static DEFINE_PER_CPU(unsigned int, efficiency_class);373static void cppc_cpufreq_register_em(struct cpufreq_policy *policy);374 375/* Create an artificial performance state every CPPC_EM_CAP_STEP capacity unit. */376#define CPPC_EM_CAP_STEP	(20)377/* Increase the cost value by CPPC_EM_COST_STEP every performance state. */378#define CPPC_EM_COST_STEP	(1)379/* Add a cost gap correspnding to the energy of 4 CPUs. */380#define CPPC_EM_COST_GAP	(4 * SCHED_CAPACITY_SCALE * CPPC_EM_COST_STEP \381				/ CPPC_EM_CAP_STEP)382 383static unsigned int get_perf_level_count(struct cpufreq_policy *policy)384{385	struct cppc_perf_caps *perf_caps;386	unsigned int min_cap, max_cap;387	struct cppc_cpudata *cpu_data;388	int cpu = policy->cpu;389 390	cpu_data = policy->driver_data;391	perf_caps = &cpu_data->perf_caps;392	max_cap = arch_scale_cpu_capacity(cpu);393	min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,394			  perf_caps->highest_perf);395	if ((min_cap == 0) || (max_cap < min_cap))396		return 0;397	return 1 + max_cap / CPPC_EM_CAP_STEP - min_cap / CPPC_EM_CAP_STEP;398}399 400/*401 * The cost is defined as:402 *   cost = power * max_frequency / frequency403 */404static inline unsigned long compute_cost(int cpu, int step)405{406	return CPPC_EM_COST_GAP * per_cpu(efficiency_class, cpu) +407			step * CPPC_EM_COST_STEP;408}409 410static int cppc_get_cpu_power(struct device *cpu_dev,411		unsigned long *power, unsigned long *KHz)412{413	unsigned long perf_step, perf_prev, perf, perf_check;414	unsigned int min_step, max_step, step, step_check;415	unsigned long prev_freq = *KHz;416	unsigned int min_cap, max_cap;417	struct cpufreq_policy *policy;418 419	struct cppc_perf_caps *perf_caps;420	struct cppc_cpudata *cpu_data;421 422	policy = cpufreq_cpu_get_raw(cpu_dev->id);423	cpu_data = policy->driver_data;424	perf_caps = &cpu_data->perf_caps;425	max_cap = arch_scale_cpu_capacity(cpu_dev->id);426	min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,427			  perf_caps->highest_perf);428	perf_step = div_u64((u64)CPPC_EM_CAP_STEP * perf_caps->highest_perf,429			    max_cap);430	min_step = min_cap / CPPC_EM_CAP_STEP;431	max_step = max_cap / CPPC_EM_CAP_STEP;432 433	perf_prev = cppc_khz_to_perf(perf_caps, *KHz);434	step = perf_prev / perf_step;435 436	if (step > max_step)437		return -EINVAL;438 439	if (min_step == max_step) {440		step = max_step;441		perf = perf_caps->highest_perf;442	} else if (step < min_step) {443		step = min_step;444		perf = perf_caps->lowest_perf;445	} else {446		step++;447		if (step == max_step)448			perf = perf_caps->highest_perf;449		else450			perf = step * perf_step;451	}452 453	*KHz = cppc_perf_to_khz(perf_caps, perf);454	perf_check = cppc_khz_to_perf(perf_caps, *KHz);455	step_check = perf_check / perf_step;456 457	/*458	 * To avoid bad integer approximation, check that new frequency value459	 * increased and that the new frequency will be converted to the460	 * desired step value.461	 */462	while ((*KHz == prev_freq) || (step_check != step)) {463		perf++;464		*KHz = cppc_perf_to_khz(perf_caps, perf);465		perf_check = cppc_khz_to_perf(perf_caps, *KHz);466		step_check = perf_check / perf_step;467	}468 469	/*470	 * With an artificial EM, only the cost value is used. Still the power471	 * is populated such as 0 < power < EM_MAX_POWER. This allows to add472	 * more sense to the artificial performance states.473	 */474	*power = compute_cost(cpu_dev->id, step);475 476	return 0;477}478 479static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,480		unsigned long *cost)481{482	unsigned long perf_step, perf_prev;483	struct cppc_perf_caps *perf_caps;484	struct cpufreq_policy *policy;485	struct cppc_cpudata *cpu_data;486	unsigned int max_cap;487	int step;488 489	policy = cpufreq_cpu_get_raw(cpu_dev->id);490	cpu_data = policy->driver_data;491	perf_caps = &cpu_data->perf_caps;492	max_cap = arch_scale_cpu_capacity(cpu_dev->id);493 494	perf_prev = cppc_khz_to_perf(perf_caps, KHz);495	perf_step = CPPC_EM_CAP_STEP * perf_caps->highest_perf / max_cap;496	step = perf_prev / perf_step;497 498	*cost = compute_cost(cpu_dev->id, step);499 500	return 0;501}502 503static int populate_efficiency_class(void)504{505	struct acpi_madt_generic_interrupt *gicc;506	DECLARE_BITMAP(used_classes, 256) = {};507	int class, cpu, index;508 509	for_each_possible_cpu(cpu) {510		gicc = acpi_cpu_get_madt_gicc(cpu);511		class = gicc->efficiency_class;512		bitmap_set(used_classes, class, 1);513	}514 515	if (bitmap_weight(used_classes, 256) <= 1) {516		pr_debug("Efficiency classes are all equal (=%d). "517			"No EM registered", class);518		return -EINVAL;519	}520 521	/*522	 * Squeeze efficiency class values on [0:#efficiency_class-1].523	 * Values are per spec in [0:255].524	 */525	index = 0;526	for_each_set_bit(class, used_classes, 256) {527		for_each_possible_cpu(cpu) {528			gicc = acpi_cpu_get_madt_gicc(cpu);529			if (gicc->efficiency_class == class)530				per_cpu(efficiency_class, cpu) = index;531		}532		index++;533	}534	cppc_cpufreq_driver.register_em = cppc_cpufreq_register_em;535 536	return 0;537}538 539static void cppc_cpufreq_register_em(struct cpufreq_policy *policy)540{541	struct cppc_cpudata *cpu_data;542	struct em_data_callback em_cb =543		EM_ADV_DATA_CB(cppc_get_cpu_power, cppc_get_cpu_cost);544 545	cpu_data = policy->driver_data;546	em_dev_register_perf_domain(get_cpu_device(policy->cpu),547			get_perf_level_count(policy), &em_cb,548			cpu_data->shared_cpu_map, 0);549}550 551#else552static int populate_efficiency_class(void)553{554	return 0;555}556#endif557 558static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu)559{560	struct cppc_cpudata *cpu_data;561	int ret;562 563	cpu_data = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL);564	if (!cpu_data)565		goto out;566 567	if (!zalloc_cpumask_var(&cpu_data->shared_cpu_map, GFP_KERNEL))568		goto free_cpu;569 570	ret = acpi_get_psd_map(cpu, cpu_data);571	if (ret) {572		pr_debug("Err parsing CPU%d PSD data: ret:%d\n", cpu, ret);573		goto free_mask;574	}575 576	ret = cppc_get_perf_caps(cpu, &cpu_data->perf_caps);577	if (ret) {578		pr_debug("Err reading CPU%d perf caps: ret:%d\n", cpu, ret);579		goto free_mask;580	}581 582	list_add(&cpu_data->node, &cpu_data_list);583 584	return cpu_data;585 586free_mask:587	free_cpumask_var(cpu_data->shared_cpu_map);588free_cpu:589	kfree(cpu_data);590out:591	return NULL;592}593 594static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy)595{596	struct cppc_cpudata *cpu_data = policy->driver_data;597 598	list_del(&cpu_data->node);599	free_cpumask_var(cpu_data->shared_cpu_map);600	kfree(cpu_data);601	policy->driver_data = NULL;602}603 604static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)605{606	unsigned int cpu = policy->cpu;607	struct cppc_cpudata *cpu_data;608	struct cppc_perf_caps *caps;609	int ret;610 611	cpu_data = cppc_cpufreq_get_cpu_data(cpu);612	if (!cpu_data) {613		pr_err("Error in acquiring _CPC/_PSD data for CPU%d.\n", cpu);614		return -ENODEV;615	}616	caps = &cpu_data->perf_caps;617	policy->driver_data = cpu_data;618 619	/*620	 * Set min to lowest nonlinear perf to avoid any efficiency penalty (see621	 * Section 8.4.7.1.1.5 of ACPI 6.1 spec)622	 */623	policy->min = cppc_perf_to_khz(caps, caps->lowest_nonlinear_perf);624	policy->max = cppc_perf_to_khz(caps, caps->nominal_perf);625 626	/*627	 * Set cpuinfo.min_freq to Lowest to make the full range of performance628	 * available if userspace wants to use any perf between lowest & lowest629	 * nonlinear perf630	 */631	policy->cpuinfo.min_freq = cppc_perf_to_khz(caps, caps->lowest_perf);632	policy->cpuinfo.max_freq = cppc_perf_to_khz(caps, caps->nominal_perf);633 634	policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu);635	policy->shared_type = cpu_data->shared_type;636 637	switch (policy->shared_type) {638	case CPUFREQ_SHARED_TYPE_HW:639	case CPUFREQ_SHARED_TYPE_NONE:640		/* Nothing to be done - we'll have a policy for each CPU */641		break;642	case CPUFREQ_SHARED_TYPE_ANY:643		/*644		 * All CPUs in the domain will share a policy and all cpufreq645		 * operations will use a single cppc_cpudata structure stored646		 * in policy->driver_data.647		 */648		cpumask_copy(policy->cpus, cpu_data->shared_cpu_map);649		break;650	default:651		pr_debug("Unsupported CPU co-ord type: %d\n",652			 policy->shared_type);653		ret = -EFAULT;654		goto out;655	}656 657	policy->fast_switch_possible = cppc_allow_fast_switch();658	policy->dvfs_possible_from_any_cpu = true;659 660	/*661	 * If 'highest_perf' is greater than 'nominal_perf', we assume CPU Boost662	 * is supported.663	 */664	if (caps->highest_perf > caps->nominal_perf)665		boost_supported = true;666 667	/* Set policy->cur to max now. The governors will adjust later. */668	policy->cur = cppc_perf_to_khz(caps, caps->highest_perf);669	cpu_data->perf_ctrls.desired_perf =  caps->highest_perf;670 671	ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);672	if (ret) {673		pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",674			 caps->highest_perf, cpu, ret);675		goto out;676	}677 678	cppc_cpufreq_cpu_fie_init(policy);679	return 0;680 681out:682	cppc_cpufreq_put_cpu_data(policy);683	return ret;684}685 686static void cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy)687{688	struct cppc_cpudata *cpu_data = policy->driver_data;689	struct cppc_perf_caps *caps = &cpu_data->perf_caps;690	unsigned int cpu = policy->cpu;691	int ret;692 693	cppc_cpufreq_cpu_fie_exit(policy);694 695	cpu_data->perf_ctrls.desired_perf = caps->lowest_perf;696 697	ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);698	if (ret)699		pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",700			 caps->lowest_perf, cpu, ret);701 702	cppc_cpufreq_put_cpu_data(policy);703}704 705static inline u64 get_delta(u64 t1, u64 t0)706{707	if (t1 > t0 || t0 > ~(u32)0)708		return t1 - t0;709 710	return (u32)t1 - (u32)t0;711}712 713static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data,714				 struct cppc_perf_fb_ctrs *fb_ctrs_t0,715				 struct cppc_perf_fb_ctrs *fb_ctrs_t1)716{717	u64 delta_reference, delta_delivered;718	u64 reference_perf;719 720	reference_perf = fb_ctrs_t0->reference_perf;721 722	delta_reference = get_delta(fb_ctrs_t1->reference,723				    fb_ctrs_t0->reference);724	delta_delivered = get_delta(fb_ctrs_t1->delivered,725				    fb_ctrs_t0->delivered);726 727	/* Check to avoid divide-by zero and invalid delivered_perf */728	if (!delta_reference || !delta_delivered)729		return cpu_data->perf_ctrls.desired_perf;730 731	return (reference_perf * delta_delivered) / delta_reference;732}733 734static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)735{736	struct cppc_perf_fb_ctrs fb_ctrs_t0 = {0}, fb_ctrs_t1 = {0};737	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);738	struct cppc_cpudata *cpu_data;739	u64 delivered_perf;740	int ret;741 742	if (!policy)743		return -ENODEV;744 745	cpu_data = policy->driver_data;746 747	cpufreq_cpu_put(policy);748 749	ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t0);750	if (ret)751		return 0;752 753	udelay(2); /* 2usec delay between sampling */754 755	ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t1);756	if (ret)757		return 0;758 759	delivered_perf = cppc_perf_from_fbctrs(cpu_data, &fb_ctrs_t0,760					       &fb_ctrs_t1);761 762	return cppc_perf_to_khz(&cpu_data->perf_caps, delivered_perf);763}764 765static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state)766{767	struct cppc_cpudata *cpu_data = policy->driver_data;768	struct cppc_perf_caps *caps = &cpu_data->perf_caps;769	int ret;770 771	if (!boost_supported) {772		pr_err("BOOST not supported by CPU or firmware\n");773		return -EINVAL;774	}775 776	if (state)777		policy->max = cppc_perf_to_khz(caps, caps->highest_perf);778	else779		policy->max = cppc_perf_to_khz(caps, caps->nominal_perf);780	policy->cpuinfo.max_freq = policy->max;781 782	ret = freq_qos_update_request(policy->max_freq_req, policy->max);783	if (ret < 0)784		return ret;785 786	return 0;787}788 789static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)790{791	struct cppc_cpudata *cpu_data = policy->driver_data;792 793	return cpufreq_show_cpus(cpu_data->shared_cpu_map, buf);794}795cpufreq_freq_attr_ro(freqdomain_cpus);796 797static struct freq_attr *cppc_cpufreq_attr[] = {798	&freqdomain_cpus,799	NULL,800};801 802static struct cpufreq_driver cppc_cpufreq_driver = {803	.flags = CPUFREQ_CONST_LOOPS,804	.verify = cppc_verify_policy,805	.target = cppc_cpufreq_set_target,806	.get = cppc_cpufreq_get_rate,807	.fast_switch = cppc_cpufreq_fast_switch,808	.init = cppc_cpufreq_cpu_init,809	.exit = cppc_cpufreq_cpu_exit,810	.set_boost = cppc_cpufreq_set_boost,811	.attr = cppc_cpufreq_attr,812	.name = "cppc_cpufreq",813};814 815/*816 * HISI platform does not support delivered performance counter and817 * reference performance counter. It can calculate the performance using the818 * platform specific mechanism. We reuse the desired performance register to819 * store the real performance calculated by the platform.820 */821static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu)822{823	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);824	struct cppc_cpudata *cpu_data;825	u64 desired_perf;826	int ret;827 828	if (!policy)829		return -ENODEV;830 831	cpu_data = policy->driver_data;832 833	cpufreq_cpu_put(policy);834 835	ret = cppc_get_desired_perf(cpu, &desired_perf);836	if (ret < 0)837		return -EIO;838 839	return cppc_perf_to_khz(&cpu_data->perf_caps, desired_perf);840}841 842static void cppc_check_hisi_workaround(void)843{844	struct acpi_table_header *tbl;845	acpi_status status = AE_OK;846	int i;847 848	status = acpi_get_table(ACPI_SIG_PCCT, 0, &tbl);849	if (ACPI_FAILURE(status) || !tbl)850		return;851 852	for (i = 0; i < ARRAY_SIZE(wa_info); i++) {853		if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) &&854		    !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) &&855		    wa_info[i].oem_revision == tbl->oem_revision) {856			/* Overwrite the get() callback */857			cppc_cpufreq_driver.get = hisi_cppc_cpufreq_get_rate;858			fie_disabled = FIE_DISABLED;859			break;860		}861	}862 863	acpi_put_table(tbl);864}865 866static int __init cppc_cpufreq_init(void)867{868	int ret;869 870	if (!acpi_cpc_valid())871		return -ENODEV;872 873	cppc_check_hisi_workaround();874	cppc_freq_invariance_init();875	populate_efficiency_class();876 877	ret = cpufreq_register_driver(&cppc_cpufreq_driver);878	if (ret)879		cppc_freq_invariance_exit();880 881	return ret;882}883 884static inline void free_cpu_data(void)885{886	struct cppc_cpudata *iter, *tmp;887 888	list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) {889		free_cpumask_var(iter->shared_cpu_map);890		list_del(&iter->node);891		kfree(iter);892	}893 894}895 896static void __exit cppc_cpufreq_exit(void)897{898	cpufreq_unregister_driver(&cppc_cpufreq_driver);899	cppc_freq_invariance_exit();900 901	free_cpu_data();902}903 904module_exit(cppc_cpufreq_exit);905MODULE_AUTHOR("Ashwin Chaugule");906MODULE_DESCRIPTION("CPUFreq driver based on the ACPI CPPC v5.0+ spec");907MODULE_LICENSE("GPL");908 909late_initcall(cppc_cpufreq_init);910 911static const struct acpi_device_id cppc_acpi_ids[] __used = {912	{ACPI_PROCESSOR_DEVICE_HID, },913	{}914};915 916MODULE_DEVICE_TABLE(acpi, cppc_acpi_ids);917