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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/powercap/dtpm_cpu.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/powercap/dtpm_cpu.c')
-rw-r--r--drivers/powercap/dtpm_cpu.c319
1 files changed, 319 insertions, 0 deletions
diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c
new file mode 100644
index 000000000..21355db64
--- /dev/null
+++ b/drivers/powercap/dtpm_cpu.c
@@ -0,0 +1,319 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 Linaro Limited
+ *
+ * Author: Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
+ * The DTPM CPU is based on the energy model. It hooks the CPU in the
+ * DTPM tree which in turns update the power number by propagating the
+ * power number from the CPU energy model information to the parents.
+ *
+ * The association between the power and the performance state, allows
+ * to set the power of the CPU at the OPP granularity.
+ *
+ * The CPU hotplug is supported and the power numbers will be updated
+ * if a CPU is hot plugged / unplugged.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cpumask.h>
+#include <linux/cpufreq.h>
+#include <linux/cpuhotplug.h>
+#include <linux/dtpm.h>
+#include <linux/energy_model.h>
+#include <linux/of.h>
+#include <linux/pm_qos.h>
+#include <linux/slab.h>
+
+struct dtpm_cpu {
+ struct dtpm dtpm;
+ struct freq_qos_request qos_req;
+ int cpu;
+};
+
+static DEFINE_PER_CPU(struct dtpm_cpu *, dtpm_per_cpu);
+
+static struct dtpm_cpu *to_dtpm_cpu(struct dtpm *dtpm)
+{
+ return container_of(dtpm, struct dtpm_cpu, dtpm);
+}
+
+static u64 set_pd_power_limit(struct dtpm *dtpm, u64 power_limit)
+{
+ struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm);
+ struct em_perf_domain *pd = em_cpu_get(dtpm_cpu->cpu);
+ struct em_perf_state *table;
+ unsigned long freq;
+ u64 power;
+ int i, nr_cpus;
+
+ nr_cpus = cpumask_weight_and(cpu_online_mask, to_cpumask(pd->cpus));
+
+ rcu_read_lock();
+ table = em_perf_state_from_pd(pd);
+ for (i = 0; i < pd->nr_perf_states; i++) {
+
+ power = table[i].power * nr_cpus;
+
+ if (power > power_limit)
+ break;
+ }
+
+ freq = table[i - 1].frequency;
+ power_limit = table[i - 1].power * nr_cpus;
+ rcu_read_unlock();
+
+ freq_qos_update_request(&dtpm_cpu->qos_req, freq);
+
+ return power_limit;
+}
+
+static u64 scale_pd_power_uw(struct cpumask *pd_mask, u64 power)
+{
+ unsigned long max, sum_util = 0;
+ int cpu;
+
+ /*
+ * The capacity is the same for all CPUs belonging to
+ * the same perf domain.
+ */
+ max = arch_scale_cpu_capacity(cpumask_first(pd_mask));
+
+ for_each_cpu_and(cpu, pd_mask, cpu_online_mask)
+ sum_util += sched_cpu_util(cpu);
+
+ return (power * ((sum_util << 10) / max)) >> 10;
+}
+
+static u64 get_pd_power_uw(struct dtpm *dtpm)
+{
+ struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm);
+ struct em_perf_state *table;
+ struct em_perf_domain *pd;
+ struct cpumask *pd_mask;
+ unsigned long freq;
+ u64 power = 0;
+ int i;
+
+ pd = em_cpu_get(dtpm_cpu->cpu);
+ if (!pd)
+ return 0;
+
+ pd_mask = em_span_cpus(pd);
+
+ freq = cpufreq_quick_get(dtpm_cpu->cpu);
+
+ rcu_read_lock();
+ table = em_perf_state_from_pd(pd);
+ for (i = 0; i < pd->nr_perf_states; i++) {
+
+ if (table[i].frequency < freq)
+ continue;
+
+ power = scale_pd_power_uw(pd_mask, table[i].power);
+ break;
+ }
+ rcu_read_unlock();
+
+ return power;
+}
+
+static int update_pd_power_uw(struct dtpm *dtpm)
+{
+ struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm);
+ struct em_perf_domain *em = em_cpu_get(dtpm_cpu->cpu);
+ struct em_perf_state *table;
+ int nr_cpus;
+
+ nr_cpus = cpumask_weight_and(cpu_online_mask, to_cpumask(em->cpus));
+
+ rcu_read_lock();
+ table = em_perf_state_from_pd(em);
+
+ dtpm->power_min = table[0].power;
+ dtpm->power_min *= nr_cpus;
+
+ dtpm->power_max = table[em->nr_perf_states - 1].power;
+ dtpm->power_max *= nr_cpus;
+
+ rcu_read_unlock();
+
+ return 0;
+}
+
+static void pd_release(struct dtpm *dtpm)
+{
+ struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm);
+ struct cpufreq_policy *policy;
+
+ if (freq_qos_request_active(&dtpm_cpu->qos_req))
+ freq_qos_remove_request(&dtpm_cpu->qos_req);
+
+ policy = cpufreq_cpu_get(dtpm_cpu->cpu);
+ if (policy) {
+ for_each_cpu(dtpm_cpu->cpu, policy->related_cpus)
+ per_cpu(dtpm_per_cpu, dtpm_cpu->cpu) = NULL;
+
+ cpufreq_cpu_put(policy);
+ }
+
+ kfree(dtpm_cpu);
+}
+
+static struct dtpm_ops dtpm_ops = {
+ .set_power_uw = set_pd_power_limit,
+ .get_power_uw = get_pd_power_uw,
+ .update_power_uw = update_pd_power_uw,
+ .release = pd_release,
+};
+
+static int cpuhp_dtpm_cpu_offline(unsigned int cpu)
+{
+ struct dtpm_cpu *dtpm_cpu;
+
+ dtpm_cpu = per_cpu(dtpm_per_cpu, cpu);
+ if (dtpm_cpu)
+ dtpm_update_power(&dtpm_cpu->dtpm);
+
+ return 0;
+}
+
+static int cpuhp_dtpm_cpu_online(unsigned int cpu)
+{
+ struct dtpm_cpu *dtpm_cpu;
+
+ dtpm_cpu = per_cpu(dtpm_per_cpu, cpu);
+ if (dtpm_cpu)
+ return dtpm_update_power(&dtpm_cpu->dtpm);
+
+ return 0;
+}
+
+static int __dtpm_cpu_setup(int cpu, struct dtpm *parent)
+{
+ struct dtpm_cpu *dtpm_cpu;
+ struct cpufreq_policy *policy;
+ struct em_perf_state *table;
+ struct em_perf_domain *pd;
+ char name[CPUFREQ_NAME_LEN];
+ int ret = -ENOMEM;
+
+ dtpm_cpu = per_cpu(dtpm_per_cpu, cpu);
+ if (dtpm_cpu)
+ return 0;
+
+ policy = cpufreq_cpu_get(cpu);
+ if (!policy)
+ return 0;
+
+ pd = em_cpu_get(cpu);
+ if (!pd || em_is_artificial(pd)) {
+ ret = -EINVAL;
+ goto release_policy;
+ }
+
+ dtpm_cpu = kzalloc_obj(*dtpm_cpu);
+ if (!dtpm_cpu) {
+ ret = -ENOMEM;
+ goto release_policy;
+ }
+
+ dtpm_init(&dtpm_cpu->dtpm, &dtpm_ops);
+ dtpm_cpu->cpu = cpu;
+
+ for_each_cpu(cpu, policy->related_cpus)
+ per_cpu(dtpm_per_cpu, cpu) = dtpm_cpu;
+
+ snprintf(name, sizeof(name), "cpu%d-cpufreq", dtpm_cpu->cpu);
+
+ ret = dtpm_register(name, &dtpm_cpu->dtpm, parent);
+ if (ret)
+ goto out_kfree_dtpm_cpu;
+
+ rcu_read_lock();
+ table = em_perf_state_from_pd(pd);
+ ret = freq_qos_add_request(&policy->constraints,
+ &dtpm_cpu->qos_req, FREQ_QOS_MAX,
+ table[pd->nr_perf_states - 1].frequency);
+ rcu_read_unlock();
+ if (ret < 0)
+ goto out_dtpm_unregister;
+
+ cpufreq_cpu_put(policy);
+ return 0;
+
+out_dtpm_unregister:
+ dtpm_unregister(&dtpm_cpu->dtpm);
+ dtpm_cpu = NULL;
+
+out_kfree_dtpm_cpu:
+ for_each_cpu(cpu, policy->related_cpus)
+ per_cpu(dtpm_per_cpu, cpu) = NULL;
+ kfree(dtpm_cpu);
+
+release_policy:
+ cpufreq_cpu_put(policy);
+ return ret;
+}
+
+static int dtpm_cpu_setup(struct dtpm *dtpm, struct device_node *np)
+{
+ int cpu;
+
+ cpu = of_cpu_node_to_id(np);
+ if (cpu < 0)
+ return 0;
+
+ return __dtpm_cpu_setup(cpu, dtpm);
+}
+
+static int dtpm_cpu_init(void)
+{
+ int ret;
+
+ /*
+ * The callbacks at CPU hotplug time are calling
+ * dtpm_update_power() which in turns calls update_pd_power().
+ *
+ * The function update_pd_power() uses the online mask to
+ * figure out the power consumption limits.
+ *
+ * At CPUHP_AP_ONLINE_DYN, the CPU is present in the CPU
+ * online mask when the cpuhp_dtpm_cpu_online function is
+ * called, but the CPU is still in the online mask for the
+ * tear down callback. So the power can not be updated when
+ * the CPU is unplugged.
+ *
+ * At CPUHP_AP_DTPM_CPU_DEAD, the situation is the opposite as
+ * above. The CPU online mask is not up to date when the CPU
+ * is plugged in.
+ *
+ * For this reason, we need to call the online and offline
+ * callbacks at different moments when the CPU online mask is
+ * consistent with the power numbers we want to update.
+ */
+ ret = cpuhp_setup_state(CPUHP_AP_DTPM_CPU_DEAD, "dtpm_cpu:offline",
+ NULL, cpuhp_dtpm_cpu_offline);
+ if (ret < 0)
+ return ret;
+
+ ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "dtpm_cpu:online",
+ cpuhp_dtpm_cpu_online, NULL);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static void dtpm_cpu_exit(void)
+{
+ cpuhp_remove_state_nocalls(CPUHP_AP_ONLINE_DYN);
+ cpuhp_remove_state_nocalls(CPUHP_AP_DTPM_CPU_DEAD);
+}
+
+struct dtpm_subsys_ops dtpm_cpu_ops = {
+ .name = KBUILD_MODNAME,
+ .init = dtpm_cpu_init,
+ .exit = dtpm_cpu_exit,
+ .setup = dtpm_cpu_setup,
+};