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-rw-r--r--drivers/cpufreq/cppc_cpufreq.c1014
1 files changed, 1014 insertions, 0 deletions
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
new file mode 100644
index 000000000..022e35554
--- /dev/null
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -0,0 +1,1014 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * CPPC (Collaborative Processor Performance Control) driver for
+ * interfacing with the CPUfreq layer and governors. See
+ * cppc_acpi.c for CPPC specific methods.
+ *
+ * (C) Copyright 2014, 2015 Linaro Ltd.
+ * Author: Ashwin Chaugule <ashwin.chaugule@linaro.org>
+ */
+
+#define pr_fmt(fmt) "CPPC Cpufreq:" fmt
+
+#include <linux/arch_topology.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/cpu.h>
+#include <linux/cpufreq.h>
+#include <linux/dmi.h>
+#include <linux/irq_work.h>
+#include <linux/kthread.h>
+#include <linux/time.h>
+#include <linux/vmalloc.h>
+#include <uapi/linux/sched/types.h>
+
+#include <asm/unaligned.h>
+
+#include <acpi/cppc_acpi.h>
+
+/* Minimum struct length needed for the DMI processor entry we want */
+#define DMI_ENTRY_PROCESSOR_MIN_LENGTH 48
+
+/* Offset in the DMI processor structure for the max frequency */
+#define DMI_PROCESSOR_MAX_SPEED 0x14
+
+/*
+ * This list contains information parsed from per CPU ACPI _CPC and _PSD
+ * structures: e.g. the highest and lowest supported performance, capabilities,
+ * desired performance, level requested etc. Depending on the share_type, not
+ * all CPUs will have an entry in the list.
+ */
+static LIST_HEAD(cpu_data_list);
+
+static bool boost_supported;
+
+struct cppc_workaround_oem_info {
+ char oem_id[ACPI_OEM_ID_SIZE + 1];
+ char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1];
+ u32 oem_revision;
+};
+
+static struct cppc_workaround_oem_info wa_info[] = {
+ {
+ .oem_id = "HISI ",
+ .oem_table_id = "HIP07 ",
+ .oem_revision = 0,
+ }, {
+ .oem_id = "HISI ",
+ .oem_table_id = "HIP08 ",
+ .oem_revision = 0,
+ }
+};
+
+static struct cpufreq_driver cppc_cpufreq_driver;
+
+static enum {
+ FIE_UNSET = -1,
+ FIE_ENABLED,
+ FIE_DISABLED
+} fie_disabled = FIE_UNSET;
+
+#ifdef CONFIG_ACPI_CPPC_CPUFREQ_FIE
+module_param(fie_disabled, int, 0444);
+MODULE_PARM_DESC(fie_disabled, "Disable Frequency Invariance Engine (FIE)");
+
+/* Frequency invariance support */
+struct cppc_freq_invariance {
+ int cpu;
+ struct irq_work irq_work;
+ struct kthread_work work;
+ struct cppc_perf_fb_ctrs prev_perf_fb_ctrs;
+ struct cppc_cpudata *cpu_data;
+};
+
+static DEFINE_PER_CPU(struct cppc_freq_invariance, cppc_freq_inv);
+static struct kthread_worker *kworker_fie;
+
+static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu);
+static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data,
+ struct cppc_perf_fb_ctrs *fb_ctrs_t0,
+ struct cppc_perf_fb_ctrs *fb_ctrs_t1);
+
+/**
+ * cppc_scale_freq_workfn - CPPC arch_freq_scale updater for frequency invariance
+ * @work: The work item.
+ *
+ * The CPPC driver register itself with the topology core to provide its own
+ * implementation (cppc_scale_freq_tick()) of topology_scale_freq_tick() which
+ * gets called by the scheduler on every tick.
+ *
+ * Note that the arch specific counters have higher priority than CPPC counters,
+ * if available, though the CPPC driver doesn't need to have any special
+ * handling for that.
+ *
+ * On an invocation of cppc_scale_freq_tick(), we schedule an irq work (since we
+ * reach here from hard-irq context), which then schedules a normal work item
+ * and cppc_scale_freq_workfn() updates the per_cpu arch_freq_scale variable
+ * based on the counter updates since the last tick.
+ */
+static void cppc_scale_freq_workfn(struct kthread_work *work)
+{
+ struct cppc_freq_invariance *cppc_fi;
+ struct cppc_perf_fb_ctrs fb_ctrs = {0};
+ struct cppc_cpudata *cpu_data;
+ unsigned long local_freq_scale;
+ u64 perf;
+
+ cppc_fi = container_of(work, struct cppc_freq_invariance, work);
+ cpu_data = cppc_fi->cpu_data;
+
+ if (cppc_get_perf_ctrs(cppc_fi->cpu, &fb_ctrs)) {
+ pr_warn("%s: failed to read perf counters\n", __func__);
+ return;
+ }
+
+ perf = cppc_perf_from_fbctrs(cpu_data, &cppc_fi->prev_perf_fb_ctrs,
+ &fb_ctrs);
+ cppc_fi->prev_perf_fb_ctrs = fb_ctrs;
+
+ perf <<= SCHED_CAPACITY_SHIFT;
+ local_freq_scale = div64_u64(perf, cpu_data->perf_caps.highest_perf);
+
+ /* This can happen due to counter's overflow */
+ if (unlikely(local_freq_scale > 1024))
+ local_freq_scale = 1024;
+
+ per_cpu(arch_freq_scale, cppc_fi->cpu) = local_freq_scale;
+}
+
+static void cppc_irq_work(struct irq_work *irq_work)
+{
+ struct cppc_freq_invariance *cppc_fi;
+
+ cppc_fi = container_of(irq_work, struct cppc_freq_invariance, irq_work);
+ kthread_queue_work(kworker_fie, &cppc_fi->work);
+}
+
+static void cppc_scale_freq_tick(void)
+{
+ struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, smp_processor_id());
+
+ /*
+ * cppc_get_perf_ctrs() can potentially sleep, call that from the right
+ * context.
+ */
+ irq_work_queue(&cppc_fi->irq_work);
+}
+
+static struct scale_freq_data cppc_sftd = {
+ .source = SCALE_FREQ_SOURCE_CPPC,
+ .set_freq_scale = cppc_scale_freq_tick,
+};
+
+static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
+{
+ struct cppc_freq_invariance *cppc_fi;
+ int cpu, ret;
+
+ if (fie_disabled)
+ return;
+
+ for_each_cpu(cpu, policy->cpus) {
+ cppc_fi = &per_cpu(cppc_freq_inv, cpu);
+ cppc_fi->cpu = cpu;
+ cppc_fi->cpu_data = policy->driver_data;
+ kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn);
+ init_irq_work(&cppc_fi->irq_work, cppc_irq_work);
+
+ ret = cppc_get_perf_ctrs(cpu, &cppc_fi->prev_perf_fb_ctrs);
+ if (ret) {
+ pr_warn("%s: failed to read perf counters for cpu:%d: %d\n",
+ __func__, cpu, ret);
+
+ /*
+ * Don't abort if the CPU was offline while the driver
+ * was getting registered.
+ */
+ if (cpu_online(cpu))
+ return;
+ }
+ }
+
+ /* Register for freq-invariance */
+ topology_set_scale_freq_source(&cppc_sftd, policy->cpus);
+}
+
+/*
+ * We free all the resources on policy's removal and not on CPU removal as the
+ * irq-work are per-cpu and the hotplug core takes care of flushing the pending
+ * irq-works (hint: smpcfd_dying_cpu()) on CPU hotplug. Even if the kthread-work
+ * fires on another CPU after the concerned CPU is removed, it won't harm.
+ *
+ * We just need to make sure to remove them all on policy->exit().
+ */
+static void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)
+{
+ struct cppc_freq_invariance *cppc_fi;
+ int cpu;
+
+ if (fie_disabled)
+ return;
+
+ /* policy->cpus will be empty here, use related_cpus instead */
+ topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_CPPC, policy->related_cpus);
+
+ for_each_cpu(cpu, policy->related_cpus) {
+ cppc_fi = &per_cpu(cppc_freq_inv, cpu);
+ irq_work_sync(&cppc_fi->irq_work);
+ kthread_cancel_work_sync(&cppc_fi->work);
+ }
+}
+
+static void __init cppc_freq_invariance_init(void)
+{
+ struct sched_attr attr = {
+ .size = sizeof(struct sched_attr),
+ .sched_policy = SCHED_DEADLINE,
+ .sched_nice = 0,
+ .sched_priority = 0,
+ /*
+ * Fake (unused) bandwidth; workaround to "fix"
+ * priority inheritance.
+ */
+ .sched_runtime = 1000000,
+ .sched_deadline = 10000000,
+ .sched_period = 10000000,
+ };
+ int ret;
+
+ if (fie_disabled != FIE_ENABLED && fie_disabled != FIE_DISABLED) {
+ fie_disabled = FIE_ENABLED;
+ if (cppc_perf_ctrs_in_pcc()) {
+ pr_info("FIE not enabled on systems with registers in PCC\n");
+ fie_disabled = FIE_DISABLED;
+ }
+ }
+
+ if (fie_disabled)
+ return;
+
+ kworker_fie = kthread_create_worker(0, "cppc_fie");
+ if (IS_ERR(kworker_fie))
+ return;
+
+ ret = sched_setattr_nocheck(kworker_fie->task, &attr);
+ if (ret) {
+ pr_warn("%s: failed to set SCHED_DEADLINE: %d\n", __func__,
+ ret);
+ kthread_destroy_worker(kworker_fie);
+ return;
+ }
+}
+
+static void cppc_freq_invariance_exit(void)
+{
+ if (fie_disabled)
+ return;
+
+ kthread_destroy_worker(kworker_fie);
+ kworker_fie = NULL;
+}
+
+#else
+static inline void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
+{
+}
+
+static inline void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)
+{
+}
+
+static inline void cppc_freq_invariance_init(void)
+{
+}
+
+static inline void cppc_freq_invariance_exit(void)
+{
+}
+#endif /* CONFIG_ACPI_CPPC_CPUFREQ_FIE */
+
+/* Callback function used to retrieve the max frequency from DMI */
+static void cppc_find_dmi_mhz(const struct dmi_header *dm, void *private)
+{
+ const u8 *dmi_data = (const u8 *)dm;
+ u16 *mhz = (u16 *)private;
+
+ if (dm->type == DMI_ENTRY_PROCESSOR &&
+ dm->length >= DMI_ENTRY_PROCESSOR_MIN_LENGTH) {
+ u16 val = (u16)get_unaligned((const u16 *)
+ (dmi_data + DMI_PROCESSOR_MAX_SPEED));
+ *mhz = val > *mhz ? val : *mhz;
+ }
+}
+
+/* Look up the max frequency in DMI */
+static u64 cppc_get_dmi_max_khz(void)
+{
+ u16 mhz = 0;
+
+ dmi_walk(cppc_find_dmi_mhz, &mhz);
+
+ /*
+ * Real stupid fallback value, just in case there is no
+ * actual value set.
+ */
+ mhz = mhz ? mhz : 1;
+
+ return (1000 * mhz);
+}
+
+/*
+ * If CPPC lowest_freq and nominal_freq registers are exposed then we can
+ * use them to convert perf to freq and vice versa. The conversion is
+ * extrapolated as an affine function passing by the 2 points:
+ * - (Low perf, Low freq)
+ * - (Nominal perf, Nominal perf)
+ */
+static unsigned int cppc_cpufreq_perf_to_khz(struct cppc_cpudata *cpu_data,
+ unsigned int perf)
+{
+ struct cppc_perf_caps *caps = &cpu_data->perf_caps;
+ s64 retval, offset = 0;
+ static u64 max_khz;
+ u64 mul, div;
+
+ if (caps->lowest_freq && caps->nominal_freq) {
+ mul = caps->nominal_freq - caps->lowest_freq;
+ div = caps->nominal_perf - caps->lowest_perf;
+ offset = caps->nominal_freq - div64_u64(caps->nominal_perf * mul, div);
+ } else {
+ if (!max_khz)
+ max_khz = cppc_get_dmi_max_khz();
+ mul = max_khz;
+ div = caps->highest_perf;
+ }
+
+ retval = offset + div64_u64(perf * mul, div);
+ if (retval >= 0)
+ return retval;
+ return 0;
+}
+
+static unsigned int cppc_cpufreq_khz_to_perf(struct cppc_cpudata *cpu_data,
+ unsigned int freq)
+{
+ struct cppc_perf_caps *caps = &cpu_data->perf_caps;
+ s64 retval, offset = 0;
+ static u64 max_khz;
+ u64 mul, div;
+
+ if (caps->lowest_freq && caps->nominal_freq) {
+ mul = caps->nominal_perf - caps->lowest_perf;
+ div = caps->nominal_freq - caps->lowest_freq;
+ offset = caps->nominal_perf - div64_u64(caps->nominal_freq * mul, div);
+ } else {
+ if (!max_khz)
+ max_khz = cppc_get_dmi_max_khz();
+ mul = caps->highest_perf;
+ div = max_khz;
+ }
+
+ retval = offset + div64_u64(freq * mul, div);
+ if (retval >= 0)
+ return retval;
+ return 0;
+}
+
+static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+
+{
+ struct cppc_cpudata *cpu_data = policy->driver_data;
+ unsigned int cpu = policy->cpu;
+ struct cpufreq_freqs freqs;
+ u32 desired_perf;
+ int ret = 0;
+
+ desired_perf = cppc_cpufreq_khz_to_perf(cpu_data, target_freq);
+ /* Return if it is exactly the same perf */
+ if (desired_perf == cpu_data->perf_ctrls.desired_perf)
+ return ret;
+
+ cpu_data->perf_ctrls.desired_perf = desired_perf;
+ freqs.old = policy->cur;
+ freqs.new = target_freq;
+
+ cpufreq_freq_transition_begin(policy, &freqs);
+ ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
+ cpufreq_freq_transition_end(policy, &freqs, ret != 0);
+
+ if (ret)
+ pr_debug("Failed to set target on CPU:%d. ret:%d\n",
+ cpu, ret);
+
+ return ret;
+}
+
+static unsigned int cppc_cpufreq_fast_switch(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ struct cppc_cpudata *cpu_data = policy->driver_data;
+ unsigned int cpu = policy->cpu;
+ u32 desired_perf;
+ int ret;
+
+ desired_perf = cppc_cpufreq_khz_to_perf(cpu_data, target_freq);
+ cpu_data->perf_ctrls.desired_perf = desired_perf;
+ ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
+
+ if (ret) {
+ pr_debug("Failed to set target on CPU:%d. ret:%d\n",
+ cpu, ret);
+ return 0;
+ }
+
+ return target_freq;
+}
+
+static int cppc_verify_policy(struct cpufreq_policy_data *policy)
+{
+ cpufreq_verify_within_cpu_limits(policy);
+ return 0;
+}
+
+/*
+ * The PCC subspace describes the rate at which platform can accept commands
+ * on the shared PCC channel (including READs which do not count towards freq
+ * transition requests), so ideally we need to use the PCC values as a fallback
+ * if we don't have a platform specific transition_delay_us
+ */
+#ifdef CONFIG_ARM64
+#include <asm/cputype.h>
+
+static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)
+{
+ unsigned long implementor = read_cpuid_implementor();
+ unsigned long part_num = read_cpuid_part_number();
+
+ switch (implementor) {
+ case ARM_CPU_IMP_QCOM:
+ switch (part_num) {
+ case QCOM_CPU_PART_FALKOR_V1:
+ case QCOM_CPU_PART_FALKOR:
+ return 10000;
+ }
+ }
+ return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
+}
+#else
+static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)
+{
+ return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
+}
+#endif
+
+#if defined(CONFIG_ARM64) && defined(CONFIG_ENERGY_MODEL)
+
+static DEFINE_PER_CPU(unsigned int, efficiency_class);
+static void cppc_cpufreq_register_em(struct cpufreq_policy *policy);
+
+/* Create an artificial performance state every CPPC_EM_CAP_STEP capacity unit. */
+#define CPPC_EM_CAP_STEP (20)
+/* Increase the cost value by CPPC_EM_COST_STEP every performance state. */
+#define CPPC_EM_COST_STEP (1)
+/* Add a cost gap correspnding to the energy of 4 CPUs. */
+#define CPPC_EM_COST_GAP (4 * SCHED_CAPACITY_SCALE * CPPC_EM_COST_STEP \
+ / CPPC_EM_CAP_STEP)
+
+static unsigned int get_perf_level_count(struct cpufreq_policy *policy)
+{
+ struct cppc_perf_caps *perf_caps;
+ unsigned int min_cap, max_cap;
+ struct cppc_cpudata *cpu_data;
+ int cpu = policy->cpu;
+
+ cpu_data = policy->driver_data;
+ perf_caps = &cpu_data->perf_caps;
+ max_cap = arch_scale_cpu_capacity(cpu);
+ min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,
+ perf_caps->highest_perf);
+ if ((min_cap == 0) || (max_cap < min_cap))
+ return 0;
+ return 1 + max_cap / CPPC_EM_CAP_STEP - min_cap / CPPC_EM_CAP_STEP;
+}
+
+/*
+ * The cost is defined as:
+ * cost = power * max_frequency / frequency
+ */
+static inline unsigned long compute_cost(int cpu, int step)
+{
+ return CPPC_EM_COST_GAP * per_cpu(efficiency_class, cpu) +
+ step * CPPC_EM_COST_STEP;
+}
+
+static int cppc_get_cpu_power(struct device *cpu_dev,
+ unsigned long *power, unsigned long *KHz)
+{
+ unsigned long perf_step, perf_prev, perf, perf_check;
+ unsigned int min_step, max_step, step, step_check;
+ unsigned long prev_freq = *KHz;
+ unsigned int min_cap, max_cap;
+ struct cpufreq_policy *policy;
+
+ struct cppc_perf_caps *perf_caps;
+ struct cppc_cpudata *cpu_data;
+
+ policy = cpufreq_cpu_get_raw(cpu_dev->id);
+ cpu_data = policy->driver_data;
+ perf_caps = &cpu_data->perf_caps;
+ max_cap = arch_scale_cpu_capacity(cpu_dev->id);
+ min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,
+ perf_caps->highest_perf);
+ perf_step = div_u64((u64)CPPC_EM_CAP_STEP * perf_caps->highest_perf,
+ max_cap);
+ min_step = min_cap / CPPC_EM_CAP_STEP;
+ max_step = max_cap / CPPC_EM_CAP_STEP;
+
+ perf_prev = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
+ step = perf_prev / perf_step;
+
+ if (step > max_step)
+ return -EINVAL;
+
+ if (min_step == max_step) {
+ step = max_step;
+ perf = perf_caps->highest_perf;
+ } else if (step < min_step) {
+ step = min_step;
+ perf = perf_caps->lowest_perf;
+ } else {
+ step++;
+ if (step == max_step)
+ perf = perf_caps->highest_perf;
+ else
+ perf = step * perf_step;
+ }
+
+ *KHz = cppc_cpufreq_perf_to_khz(cpu_data, perf);
+ perf_check = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
+ step_check = perf_check / perf_step;
+
+ /*
+ * To avoid bad integer approximation, check that new frequency value
+ * increased and that the new frequency will be converted to the
+ * desired step value.
+ */
+ while ((*KHz == prev_freq) || (step_check != step)) {
+ perf++;
+ *KHz = cppc_cpufreq_perf_to_khz(cpu_data, perf);
+ perf_check = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
+ step_check = perf_check / perf_step;
+ }
+
+ /*
+ * With an artificial EM, only the cost value is used. Still the power
+ * is populated such as 0 < power < EM_MAX_POWER. This allows to add
+ * more sense to the artificial performance states.
+ */
+ *power = compute_cost(cpu_dev->id, step);
+
+ return 0;
+}
+
+static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,
+ unsigned long *cost)
+{
+ unsigned long perf_step, perf_prev;
+ struct cppc_perf_caps *perf_caps;
+ struct cpufreq_policy *policy;
+ struct cppc_cpudata *cpu_data;
+ unsigned int max_cap;
+ int step;
+
+ policy = cpufreq_cpu_get_raw(cpu_dev->id);
+ cpu_data = policy->driver_data;
+ perf_caps = &cpu_data->perf_caps;
+ max_cap = arch_scale_cpu_capacity(cpu_dev->id);
+
+ perf_prev = cppc_cpufreq_khz_to_perf(cpu_data, KHz);
+ perf_step = CPPC_EM_CAP_STEP * perf_caps->highest_perf / max_cap;
+ step = perf_prev / perf_step;
+
+ *cost = compute_cost(cpu_dev->id, step);
+
+ return 0;
+}
+
+static int populate_efficiency_class(void)
+{
+ struct acpi_madt_generic_interrupt *gicc;
+ DECLARE_BITMAP(used_classes, 256) = {};
+ int class, cpu, index;
+
+ for_each_possible_cpu(cpu) {
+ gicc = acpi_cpu_get_madt_gicc(cpu);
+ class = gicc->efficiency_class;
+ bitmap_set(used_classes, class, 1);
+ }
+
+ if (bitmap_weight(used_classes, 256) <= 1) {
+ pr_debug("Efficiency classes are all equal (=%d). "
+ "No EM registered", class);
+ return -EINVAL;
+ }
+
+ /*
+ * Squeeze efficiency class values on [0:#efficiency_class-1].
+ * Values are per spec in [0:255].
+ */
+ index = 0;
+ for_each_set_bit(class, used_classes, 256) {
+ for_each_possible_cpu(cpu) {
+ gicc = acpi_cpu_get_madt_gicc(cpu);
+ if (gicc->efficiency_class == class)
+ per_cpu(efficiency_class, cpu) = index;
+ }
+ index++;
+ }
+ cppc_cpufreq_driver.register_em = cppc_cpufreq_register_em;
+
+ return 0;
+}
+
+static void cppc_cpufreq_register_em(struct cpufreq_policy *policy)
+{
+ struct cppc_cpudata *cpu_data;
+ struct em_data_callback em_cb =
+ EM_ADV_DATA_CB(cppc_get_cpu_power, cppc_get_cpu_cost);
+
+ cpu_data = policy->driver_data;
+ em_dev_register_perf_domain(get_cpu_device(policy->cpu),
+ get_perf_level_count(policy), &em_cb,
+ cpu_data->shared_cpu_map, 0);
+}
+
+#else
+static int populate_efficiency_class(void)
+{
+ return 0;
+}
+#endif
+
+static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu)
+{
+ struct cppc_cpudata *cpu_data;
+ int ret;
+
+ cpu_data = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL);
+ if (!cpu_data)
+ goto out;
+
+ if (!zalloc_cpumask_var(&cpu_data->shared_cpu_map, GFP_KERNEL))
+ goto free_cpu;
+
+ ret = acpi_get_psd_map(cpu, cpu_data);
+ if (ret) {
+ pr_debug("Err parsing CPU%d PSD data: ret:%d\n", cpu, ret);
+ goto free_mask;
+ }
+
+ ret = cppc_get_perf_caps(cpu, &cpu_data->perf_caps);
+ if (ret) {
+ pr_debug("Err reading CPU%d perf caps: ret:%d\n", cpu, ret);
+ goto free_mask;
+ }
+
+ /* Convert the lowest and nominal freq from MHz to KHz */
+ cpu_data->perf_caps.lowest_freq *= 1000;
+ cpu_data->perf_caps.nominal_freq *= 1000;
+
+ list_add(&cpu_data->node, &cpu_data_list);
+
+ return cpu_data;
+
+free_mask:
+ free_cpumask_var(cpu_data->shared_cpu_map);
+free_cpu:
+ kfree(cpu_data);
+out:
+ return NULL;
+}
+
+static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy)
+{
+ struct cppc_cpudata *cpu_data = policy->driver_data;
+
+ list_del(&cpu_data->node);
+ free_cpumask_var(cpu_data->shared_cpu_map);
+ kfree(cpu_data);
+ policy->driver_data = NULL;
+}
+
+static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+ unsigned int cpu = policy->cpu;
+ struct cppc_cpudata *cpu_data;
+ struct cppc_perf_caps *caps;
+ int ret;
+
+ cpu_data = cppc_cpufreq_get_cpu_data(cpu);
+ if (!cpu_data) {
+ pr_err("Error in acquiring _CPC/_PSD data for CPU%d.\n", cpu);
+ return -ENODEV;
+ }
+ caps = &cpu_data->perf_caps;
+ policy->driver_data = cpu_data;
+
+ /*
+ * Set min to lowest nonlinear perf to avoid any efficiency penalty (see
+ * Section 8.4.7.1.1.5 of ACPI 6.1 spec)
+ */
+ policy->min = cppc_cpufreq_perf_to_khz(cpu_data,
+ caps->lowest_nonlinear_perf);
+ policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
+ caps->nominal_perf);
+
+ /*
+ * Set cpuinfo.min_freq to Lowest to make the full range of performance
+ * available if userspace wants to use any perf between lowest & lowest
+ * nonlinear perf
+ */
+ policy->cpuinfo.min_freq = cppc_cpufreq_perf_to_khz(cpu_data,
+ caps->lowest_perf);
+ policy->cpuinfo.max_freq = cppc_cpufreq_perf_to_khz(cpu_data,
+ caps->nominal_perf);
+
+ policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu);
+ policy->shared_type = cpu_data->shared_type;
+
+ switch (policy->shared_type) {
+ case CPUFREQ_SHARED_TYPE_HW:
+ case CPUFREQ_SHARED_TYPE_NONE:
+ /* Nothing to be done - we'll have a policy for each CPU */
+ break;
+ case CPUFREQ_SHARED_TYPE_ANY:
+ /*
+ * All CPUs in the domain will share a policy and all cpufreq
+ * operations will use a single cppc_cpudata structure stored
+ * in policy->driver_data.
+ */
+ cpumask_copy(policy->cpus, cpu_data->shared_cpu_map);
+ break;
+ default:
+ pr_debug("Unsupported CPU co-ord type: %d\n",
+ policy->shared_type);
+ ret = -EFAULT;
+ goto out;
+ }
+
+ policy->fast_switch_possible = cppc_allow_fast_switch();
+ policy->dvfs_possible_from_any_cpu = true;
+
+ /*
+ * If 'highest_perf' is greater than 'nominal_perf', we assume CPU Boost
+ * is supported.
+ */
+ if (caps->highest_perf > caps->nominal_perf)
+ boost_supported = true;
+
+ /* Set policy->cur to max now. The governors will adjust later. */
+ policy->cur = cppc_cpufreq_perf_to_khz(cpu_data, caps->highest_perf);
+ cpu_data->perf_ctrls.desired_perf = caps->highest_perf;
+
+ ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
+ if (ret) {
+ pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
+ caps->highest_perf, cpu, ret);
+ goto out;
+ }
+
+ cppc_cpufreq_cpu_fie_init(policy);
+ return 0;
+
+out:
+ cppc_cpufreq_put_cpu_data(policy);
+ return ret;
+}
+
+static int cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy)
+{
+ struct cppc_cpudata *cpu_data = policy->driver_data;
+ struct cppc_perf_caps *caps = &cpu_data->perf_caps;
+ unsigned int cpu = policy->cpu;
+ int ret;
+
+ cppc_cpufreq_cpu_fie_exit(policy);
+
+ cpu_data->perf_ctrls.desired_perf = caps->lowest_perf;
+
+ ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
+ if (ret)
+ pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
+ caps->lowest_perf, cpu, ret);
+
+ cppc_cpufreq_put_cpu_data(policy);
+ return 0;
+}
+
+static inline u64 get_delta(u64 t1, u64 t0)
+{
+ if (t1 > t0 || t0 > ~(u32)0)
+ return t1 - t0;
+
+ return (u32)t1 - (u32)t0;
+}
+
+static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data,
+ struct cppc_perf_fb_ctrs *fb_ctrs_t0,
+ struct cppc_perf_fb_ctrs *fb_ctrs_t1)
+{
+ u64 delta_reference, delta_delivered;
+ u64 reference_perf;
+
+ reference_perf = fb_ctrs_t0->reference_perf;
+
+ delta_reference = get_delta(fb_ctrs_t1->reference,
+ fb_ctrs_t0->reference);
+ delta_delivered = get_delta(fb_ctrs_t1->delivered,
+ fb_ctrs_t0->delivered);
+
+ /* Check to avoid divide-by zero and invalid delivered_perf */
+ if (!delta_reference || !delta_delivered)
+ return cpu_data->perf_ctrls.desired_perf;
+
+ return (reference_perf * delta_delivered) / delta_reference;
+}
+
+static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)
+{
+ struct cppc_perf_fb_ctrs fb_ctrs_t0 = {0}, fb_ctrs_t1 = {0};
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ struct cppc_cpudata *cpu_data = policy->driver_data;
+ u64 delivered_perf;
+ int ret;
+
+ cpufreq_cpu_put(policy);
+
+ ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t0);
+ if (ret)
+ return ret;
+
+ udelay(2); /* 2usec delay between sampling */
+
+ ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t1);
+ if (ret)
+ return ret;
+
+ delivered_perf = cppc_perf_from_fbctrs(cpu_data, &fb_ctrs_t0,
+ &fb_ctrs_t1);
+
+ return cppc_cpufreq_perf_to_khz(cpu_data, delivered_perf);
+}
+
+static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state)
+{
+ struct cppc_cpudata *cpu_data = policy->driver_data;
+ struct cppc_perf_caps *caps = &cpu_data->perf_caps;
+ int ret;
+
+ if (!boost_supported) {
+ pr_err("BOOST not supported by CPU or firmware\n");
+ return -EINVAL;
+ }
+
+ if (state)
+ policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
+ caps->highest_perf);
+ else
+ policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
+ caps->nominal_perf);
+ policy->cpuinfo.max_freq = policy->max;
+
+ ret = freq_qos_update_request(policy->max_freq_req, policy->max);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
+{
+ struct cppc_cpudata *cpu_data = policy->driver_data;
+
+ return cpufreq_show_cpus(cpu_data->shared_cpu_map, buf);
+}
+cpufreq_freq_attr_ro(freqdomain_cpus);
+
+static struct freq_attr *cppc_cpufreq_attr[] = {
+ &freqdomain_cpus,
+ NULL,
+};
+
+static struct cpufreq_driver cppc_cpufreq_driver = {
+ .flags = CPUFREQ_CONST_LOOPS,
+ .verify = cppc_verify_policy,
+ .target = cppc_cpufreq_set_target,
+ .get = cppc_cpufreq_get_rate,
+ .fast_switch = cppc_cpufreq_fast_switch,
+ .init = cppc_cpufreq_cpu_init,
+ .exit = cppc_cpufreq_cpu_exit,
+ .set_boost = cppc_cpufreq_set_boost,
+ .attr = cppc_cpufreq_attr,
+ .name = "cppc_cpufreq",
+};
+
+/*
+ * HISI platform does not support delivered performance counter and
+ * reference performance counter. It can calculate the performance using the
+ * platform specific mechanism. We reuse the desired performance register to
+ * store the real performance calculated by the platform.
+ */
+static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ struct cppc_cpudata *cpu_data = policy->driver_data;
+ u64 desired_perf;
+ int ret;
+
+ cpufreq_cpu_put(policy);
+
+ ret = cppc_get_desired_perf(cpu, &desired_perf);
+ if (ret < 0)
+ return -EIO;
+
+ return cppc_cpufreq_perf_to_khz(cpu_data, desired_perf);
+}
+
+static void cppc_check_hisi_workaround(void)
+{
+ struct acpi_table_header *tbl;
+ acpi_status status = AE_OK;
+ int i;
+
+ status = acpi_get_table(ACPI_SIG_PCCT, 0, &tbl);
+ if (ACPI_FAILURE(status) || !tbl)
+ return;
+
+ for (i = 0; i < ARRAY_SIZE(wa_info); i++) {
+ if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) &&
+ !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) &&
+ wa_info[i].oem_revision == tbl->oem_revision) {
+ /* Overwrite the get() callback */
+ cppc_cpufreq_driver.get = hisi_cppc_cpufreq_get_rate;
+ fie_disabled = FIE_DISABLED;
+ break;
+ }
+ }
+
+ acpi_put_table(tbl);
+}
+
+static int __init cppc_cpufreq_init(void)
+{
+ int ret;
+
+ if (!acpi_cpc_valid())
+ return -ENODEV;
+
+ cppc_check_hisi_workaround();
+ cppc_freq_invariance_init();
+ populate_efficiency_class();
+
+ ret = cpufreq_register_driver(&cppc_cpufreq_driver);
+ if (ret)
+ cppc_freq_invariance_exit();
+
+ return ret;
+}
+
+static inline void free_cpu_data(void)
+{
+ struct cppc_cpudata *iter, *tmp;
+
+ list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) {
+ free_cpumask_var(iter->shared_cpu_map);
+ list_del(&iter->node);
+ kfree(iter);
+ }
+
+}
+
+static void __exit cppc_cpufreq_exit(void)
+{
+ cpufreq_unregister_driver(&cppc_cpufreq_driver);
+ cppc_freq_invariance_exit();
+
+ free_cpu_data();
+}
+
+module_exit(cppc_cpufreq_exit);
+MODULE_AUTHOR("Ashwin Chaugule");
+MODULE_DESCRIPTION("CPUFreq driver based on the ACPI CPPC v5.0+ spec");
+MODULE_LICENSE("GPL");
+
+late_initcall(cppc_cpufreq_init);
+
+static const struct acpi_device_id cppc_acpi_ids[] __used = {
+ {ACPI_PROCESSOR_DEVICE_HID, },
+ {}
+};
+
+MODULE_DEVICE_TABLE(acpi, cppc_acpi_ids);