v4.19.13 snapshot.
diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c
new file mode 100644
index 0000000..59c3a5d
--- /dev/null
+++ b/drivers/acpi/processor_thermal.c
@@ -0,0 +1,272 @@
+/*
+ * processor_thermal.c - Passive cooling submodule of the ACPI processor driver
+ *
+ * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
+ * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+ * - Added processor hotplug support
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/cpufreq.h>
+#include <linux/acpi.h>
+#include <acpi/processor.h>
+#include <linux/uaccess.h>
+
+#define PREFIX "ACPI: "
+
+#define ACPI_PROCESSOR_CLASS "processor"
+#define _COMPONENT ACPI_PROCESSOR_COMPONENT
+ACPI_MODULE_NAME("processor_thermal");
+
+#ifdef CONFIG_CPU_FREQ
+
+/* If a passive cooling situation is detected, primarily CPUfreq is used, as it
+ * offers (in most cases) voltage scaling in addition to frequency scaling, and
+ * thus a cubic (instead of linear) reduction of energy. Also, we allow for
+ * _any_ cpufreq driver and not only the acpi-cpufreq driver.
+ */
+
+#define CPUFREQ_THERMAL_MIN_STEP 0
+#define CPUFREQ_THERMAL_MAX_STEP 3
+
+static DEFINE_PER_CPU(unsigned int, cpufreq_thermal_reduction_pctg);
+static unsigned int acpi_thermal_cpufreq_is_init = 0;
+
+#define reduction_pctg(cpu) \
+ per_cpu(cpufreq_thermal_reduction_pctg, phys_package_first_cpu(cpu))
+
+/*
+ * Emulate "per package data" using per cpu data (which should really be
+ * provided elsewhere)
+ *
+ * Note we can lose a CPU on cpu hotunplug, in this case we forget the state
+ * temporarily. Fortunately that's not a big issue here (I hope)
+ */
+static int phys_package_first_cpu(int cpu)
+{
+ int i;
+ int id = topology_physical_package_id(cpu);
+
+ for_each_online_cpu(i)
+ if (topology_physical_package_id(i) == id)
+ return i;
+ return 0;
+}
+
+static int cpu_has_cpufreq(unsigned int cpu)
+{
+ struct cpufreq_policy policy;
+ if (!acpi_thermal_cpufreq_is_init || cpufreq_get_policy(&policy, cpu))
+ return 0;
+ return 1;
+}
+
+static int acpi_thermal_cpufreq_notifier(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct cpufreq_policy *policy = data;
+ unsigned long max_freq = 0;
+
+ if (event != CPUFREQ_ADJUST)
+ goto out;
+
+ max_freq = (
+ policy->cpuinfo.max_freq *
+ (100 - reduction_pctg(policy->cpu) * 20)
+ ) / 100;
+
+ cpufreq_verify_within_limits(policy, 0, max_freq);
+
+ out:
+ return 0;
+}
+
+static struct notifier_block acpi_thermal_cpufreq_notifier_block = {
+ .notifier_call = acpi_thermal_cpufreq_notifier,
+};
+
+static int cpufreq_get_max_state(unsigned int cpu)
+{
+ if (!cpu_has_cpufreq(cpu))
+ return 0;
+
+ return CPUFREQ_THERMAL_MAX_STEP;
+}
+
+static int cpufreq_get_cur_state(unsigned int cpu)
+{
+ if (!cpu_has_cpufreq(cpu))
+ return 0;
+
+ return reduction_pctg(cpu);
+}
+
+static int cpufreq_set_cur_state(unsigned int cpu, int state)
+{
+ int i;
+
+ if (!cpu_has_cpufreq(cpu))
+ return 0;
+
+ reduction_pctg(cpu) = state;
+
+ /*
+ * Update all the CPUs in the same package because they all
+ * contribute to the temperature and often share the same
+ * frequency.
+ */
+ for_each_online_cpu(i) {
+ if (topology_physical_package_id(i) ==
+ topology_physical_package_id(cpu))
+ cpufreq_update_policy(i);
+ }
+ return 0;
+}
+
+void acpi_thermal_cpufreq_init(void)
+{
+ int i;
+
+ i = cpufreq_register_notifier(&acpi_thermal_cpufreq_notifier_block,
+ CPUFREQ_POLICY_NOTIFIER);
+ if (!i)
+ acpi_thermal_cpufreq_is_init = 1;
+}
+
+void acpi_thermal_cpufreq_exit(void)
+{
+ if (acpi_thermal_cpufreq_is_init)
+ cpufreq_unregister_notifier
+ (&acpi_thermal_cpufreq_notifier_block,
+ CPUFREQ_POLICY_NOTIFIER);
+
+ acpi_thermal_cpufreq_is_init = 0;
+}
+
+#else /* ! CONFIG_CPU_FREQ */
+static int cpufreq_get_max_state(unsigned int cpu)
+{
+ return 0;
+}
+
+static int cpufreq_get_cur_state(unsigned int cpu)
+{
+ return 0;
+}
+
+static int cpufreq_set_cur_state(unsigned int cpu, int state)
+{
+ return 0;
+}
+
+#endif
+
+/* thermal cooling device callbacks */
+static int acpi_processor_max_state(struct acpi_processor *pr)
+{
+ int max_state = 0;
+
+ /*
+ * There exists four states according to
+ * cpufreq_thermal_reduction_pctg. 0, 1, 2, 3
+ */
+ max_state += cpufreq_get_max_state(pr->id);
+ if (pr->flags.throttling)
+ max_state += (pr->throttling.state_count -1);
+
+ return max_state;
+}
+static int
+processor_get_max_state(struct thermal_cooling_device *cdev,
+ unsigned long *state)
+{
+ struct acpi_device *device = cdev->devdata;
+ struct acpi_processor *pr;
+
+ if (!device)
+ return -EINVAL;
+
+ pr = acpi_driver_data(device);
+ if (!pr)
+ return -EINVAL;
+
+ *state = acpi_processor_max_state(pr);
+ return 0;
+}
+
+static int
+processor_get_cur_state(struct thermal_cooling_device *cdev,
+ unsigned long *cur_state)
+{
+ struct acpi_device *device = cdev->devdata;
+ struct acpi_processor *pr;
+
+ if (!device)
+ return -EINVAL;
+
+ pr = acpi_driver_data(device);
+ if (!pr)
+ return -EINVAL;
+
+ *cur_state = cpufreq_get_cur_state(pr->id);
+ if (pr->flags.throttling)
+ *cur_state += pr->throttling.state;
+ return 0;
+}
+
+static int
+processor_set_cur_state(struct thermal_cooling_device *cdev,
+ unsigned long state)
+{
+ struct acpi_device *device = cdev->devdata;
+ struct acpi_processor *pr;
+ int result = 0;
+ int max_pstate;
+
+ if (!device)
+ return -EINVAL;
+
+ pr = acpi_driver_data(device);
+ if (!pr)
+ return -EINVAL;
+
+ max_pstate = cpufreq_get_max_state(pr->id);
+
+ if (state > acpi_processor_max_state(pr))
+ return -EINVAL;
+
+ if (state <= max_pstate) {
+ if (pr->flags.throttling && pr->throttling.state)
+ result = acpi_processor_set_throttling(pr, 0, false);
+ cpufreq_set_cur_state(pr->id, state);
+ } else {
+ cpufreq_set_cur_state(pr->id, max_pstate);
+ result = acpi_processor_set_throttling(pr,
+ state - max_pstate, false);
+ }
+ return result;
+}
+
+const struct thermal_cooling_device_ops processor_cooling_ops = {
+ .get_max_state = processor_get_max_state,
+ .get_cur_state = processor_get_cur_state,
+ .set_cur_state = processor_set_cur_state,
+};