Merge tag 'cpufreq-arm-updates-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm

Pull CPUFreq Arm updates for 7.0 from Viresh Kumar:

"- Update cpufreq-dt-platdev list for tegra, qcom, TI (Aaron Kling,
   Dhruva Gole, and Konrad Dybcio).

 - Minor improvements to the cpufreq / cpumask rust implementation
   (Alexandre Courbot, Alice Ryhl, Tamir Duberstein, and Yilin Chen).

 - Add support for AM62L3 SoC to ti-cpufreq driver (Dhruva Gole).

 - Update FIE arch_freq_scale in ticks for non-PCC regs (Jie Zhan).

 - Other minor cleanups / improvements (Felix Gu, Juan Martinez, Luca
   Weiss, and Sergey Shtylyov)."

* tag 'cpufreq-arm-updates-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
  cpufreq: scmi: Fix device_node reference leak in scmi_cpu_domain_id()
  cpufreq: ti-cpufreq: add support for AM62L3 SoC
  cpufreq: dt-platdev: Add ti,am62l3 to blocklist
  cpufreq/amd-pstate: Add comment explaining nominal_perf usage for performance policy
  cpufreq: scmi: correct SCMI explanation
  cpufreq: dt-platdev: Block the driver from probing on more QC platforms
  rust: cpumask: rename methods of Cpumask for clarity and consistency
  cpufreq: CPPC: Update FIE arch_freq_scale in ticks for non-PCC regs
  cpufreq: CPPC: Factor out cppc_fie_kworker_init()
  ACPI: CPPC: Factor out and export per-cpu cppc_perf_ctrs_in_pcc_cpu()
  rust: cpufreq: replace `kernel::c_str!` with C-Strings
  cpufreq: Add Tegra186 and Tegra194 to cpufreq-dt-platdev blocklist
  dt-bindings: cpufreq: qcom-hw: document Milos CPUFREQ Hardware
  rust: cpufreq: add __rust_helper to helpers
  rust: cpufreq: always inline functions using build_assert with arguments

Author: rafaeljw

Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml

@@ -35,6 +35,7 @@ properties:
       - description: v2 of CPUFREQ HW (EPSS)
         items:
           - enum:
+              - qcom,milos-cpufreq-epss
               - qcom,qcs8300-cpufreq-epss
               - qcom,qdu1000-cpufreq-epss
               - qcom,sa8255p-cpufreq-epss
@@ -169,6 +170,7 @@ allOf:
         compatible:
           contains:
             enum:
+              - qcom,milos-cpufreq-epss
               - qcom,qcs8300-cpufreq-epss
               - qcom,sc7280-cpufreq-epss
               - qcom,sm8250-cpufreq-epss

drivers/acpi/cppc_acpi.c

@@ -1423,6 +1423,32 @@ int cppc_get_perf_caps(int cpunum, struct cppc_perf_caps *perf_caps)
 }
 EXPORT_SYMBOL_GPL(cppc_get_perf_caps);
 
+/**
+ * cppc_perf_ctrs_in_pcc_cpu - Check if any perf counters of a CPU are in PCC.
+ * @cpu: CPU on which to check perf counters.
+ *
+ * Return: true if any of the counters are in PCC regions, false otherwise
+ */
+bool cppc_perf_ctrs_in_pcc_cpu(unsigned int cpu)
+{
+	struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu);
+	struct cpc_register_resource *ref_perf_reg;
+
+	/*
+	 * If reference perf register is not supported then we should use the
+	 * nominal perf value
+	 */
+	ref_perf_reg = &cpc_desc->cpc_regs[REFERENCE_PERF];
+	if (!CPC_SUPPORTED(ref_perf_reg))
+		ref_perf_reg = &cpc_desc->cpc_regs[NOMINAL_PERF];
+
+	return CPC_IN_PCC(&cpc_desc->cpc_regs[DELIVERED_CTR]) ||
+		CPC_IN_PCC(&cpc_desc->cpc_regs[REFERENCE_CTR]) ||
+		CPC_IN_PCC(&cpc_desc->cpc_regs[CTR_WRAP_TIME]) ||
+		CPC_IN_PCC(ref_perf_reg);
+}
+EXPORT_SYMBOL_GPL(cppc_perf_ctrs_in_pcc_cpu);
+
 /**
  * cppc_perf_ctrs_in_pcc - Check if any perf counters are in a PCC region.
  *
@@ -1437,27 +1463,7 @@ bool cppc_perf_ctrs_in_pcc(void)
 	int cpu;
 
 	for_each_online_cpu(cpu) {
-		struct cpc_register_resource *ref_perf_reg;
-		struct cpc_desc *cpc_desc;
-
-		cpc_desc = per_cpu(cpc_desc_ptr, cpu);
-
-		if (CPC_IN_PCC(&cpc_desc->cpc_regs[DELIVERED_CTR]) ||
-		    CPC_IN_PCC(&cpc_desc->cpc_regs[REFERENCE_CTR]) ||
-		    CPC_IN_PCC(&cpc_desc->cpc_regs[CTR_WRAP_TIME]))
-			return true;
-
-
-		ref_perf_reg = &cpc_desc->cpc_regs[REFERENCE_PERF];
-
-		/*
-		 * If reference perf register is not supported then we should
-		 * use the nominal perf value
-		 */
-		if (!CPC_SUPPORTED(ref_perf_reg))
-			ref_perf_reg = &cpc_desc->cpc_regs[NOMINAL_PERF];
-
-		if (CPC_IN_PCC(ref_perf_reg))
+		if (cppc_perf_ctrs_in_pcc_cpu(cpu))
 			return true;
 	}
 

drivers/cpufreq/amd-pstate.c

@@ -636,6 +636,19 @@ static void amd_pstate_update_min_max_limit(struct cpufreq_policy *policy)
 	WRITE_ONCE(cpudata->max_limit_freq, policy->max);
 
 	if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
+		/*
+		 * For performance policy, set MinPerf to nominal_perf rather than
+		 * highest_perf or lowest_nonlinear_perf.
+		 *
+		 * Per commit 0c411b39e4f4c, using highest_perf was observed
+		 * to cause frequency throttling on power-limited platforms, leading to
+		 * performance regressions. Using lowest_nonlinear_perf would limit
+		 * performance too much for HPC workloads requiring high frequency
+		 * operation and minimal wakeup latency from idle states.
+		 *
+		 * nominal_perf therefore provides a balance by avoiding throttling
+		 * while still maintaining enough performance for HPC workloads.
+		 */
 		perf.min_limit_perf = min(perf.nominal_perf, perf.max_limit_perf);
 		WRITE_ONCE(cpudata->min_limit_freq, min(cpudata->nominal_freq, cpudata->max_limit_freq));
 	} else {

drivers/cpufreq/cppc_cpufreq.c

@@ -54,31 +54,24 @@ static int cppc_perf_from_fbctrs(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.
+ * __cppc_scale_freq_tick - CPPC arch_freq_scale updater for frequency invariance
+ * @cppc_fi: per-cpu CPPC FIE data.
  *
- * The CPPC driver register itself with the topology core to provide its own
+ * The CPPC driver registers 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)
+static void __cppc_scale_freq_tick(struct cppc_freq_invariance *cppc_fi)
 {
-	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)) {
@@ -102,6 +95,24 @@ static void cppc_scale_freq_workfn(struct kthread_work *work)
 	per_cpu(arch_freq_scale, cppc_fi->cpu) = local_freq_scale;
 }
 
+static void cppc_scale_freq_tick(void)
+{
+	__cppc_scale_freq_tick(&per_cpu(cppc_freq_inv, smp_processor_id()));
+}
+
+static struct scale_freq_data cppc_sftd = {
+	.source = SCALE_FREQ_SOURCE_CPPC,
+	.set_freq_scale = cppc_scale_freq_tick,
+};
+
+static void cppc_scale_freq_workfn(struct kthread_work *work)
+{
+	struct cppc_freq_invariance *cppc_fi;
+
+	cppc_fi = container_of(work, struct cppc_freq_invariance, work);
+	__cppc_scale_freq_tick(cppc_fi);
+}
+
 static void cppc_irq_work(struct irq_work *irq_work)
 {
 	struct cppc_freq_invariance *cppc_fi;
@@ -110,7 +121,14 @@ static void cppc_irq_work(struct irq_work *irq_work)
 	kthread_queue_work(kworker_fie, &cppc_fi->work);
 }
 
-static void cppc_scale_freq_tick(void)
+/*
+ * Reading perf counters may sleep if the CPC regs are in PCC.  Thus, we
+ * schedule an irq work in scale_freq_tick (since we reach here from hard-irq
+ * context), which then schedules a normal work item cppc_scale_freq_workfn()
+ * that updates the per_cpu arch_freq_scale variable based on the counter
+ * updates since the last tick.
+ */
+static void cppc_scale_freq_tick_pcc(void)
 {
 	struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, smp_processor_id());
 
@@ -121,13 +139,14 @@ static void cppc_scale_freq_tick(void)
 	irq_work_queue(&cppc_fi->irq_work);
 }
 
-static struct scale_freq_data cppc_sftd = {
+static struct scale_freq_data cppc_sftd_pcc = {
 	.source = SCALE_FREQ_SOURCE_CPPC,
-	.set_freq_scale = cppc_scale_freq_tick,
+	.set_freq_scale = cppc_scale_freq_tick_pcc,
 };
 
 static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
 {
+	struct scale_freq_data *sftd = &cppc_sftd;
 	struct cppc_freq_invariance *cppc_fi;
 	int cpu, ret;
 
@@ -138,8 +157,11 @@ static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
 		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);
+		if (cppc_perf_ctrs_in_pcc_cpu(cpu)) {
+			kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn);
+			init_irq_work(&cppc_fi->irq_work, cppc_irq_work);
+			sftd = &cppc_sftd_pcc;
+		}
 
 		ret = cppc_get_perf_ctrs(cpu, &cppc_fi->prev_perf_fb_ctrs);
 
@@ -155,7 +177,7 @@ static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
 	}
 
 	/* Register for freq-invariance */
-	topology_set_scale_freq_source(&cppc_sftd, policy->cpus);
+	topology_set_scale_freq_source(sftd, policy->cpus);
 }
 
 /*
@@ -178,13 +200,15 @@ static void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)
 	topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_CPPC, policy->related_cpus);
 
 	for_each_cpu(cpu, policy->related_cpus) {
+		if (!cppc_perf_ctrs_in_pcc_cpu(cpu))
+			continue;
 		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)
+static void cppc_fie_kworker_init(void)
 {
 	struct sched_attr attr = {
 		.size		= sizeof(struct sched_attr),
@@ -201,22 +225,12 @@ static void __init cppc_freq_invariance_init(void)
 	};
 	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_run_worker(0, "cppc_fie");
 	if (IS_ERR(kworker_fie)) {
 		pr_warn("%s: failed to create kworker_fie: %ld\n", __func__,
 			PTR_ERR(kworker_fie));
 		fie_disabled = FIE_DISABLED;
+		kworker_fie = NULL;
 		return;
 	}
 
@@ -226,15 +240,33 @@ static void __init cppc_freq_invariance_init(void)
 			ret);
 		kthread_destroy_worker(kworker_fie);
 		fie_disabled = FIE_DISABLED;
+		kworker_fie = NULL;
 	}
 }
 
-static void cppc_freq_invariance_exit(void)
+static void __init cppc_freq_invariance_init(void)
 {
-	if (fie_disabled)
+	bool perf_ctrs_in_pcc = cppc_perf_ctrs_in_pcc();
+
+	if (fie_disabled == FIE_UNSET) {
+		if (perf_ctrs_in_pcc) {
+			pr_info("FIE not enabled on systems with registers in PCC\n");
+			fie_disabled = FIE_DISABLED;
+		} else {
+			fie_disabled = FIE_ENABLED;
+		}
+	}
+
+	if (fie_disabled || !perf_ctrs_in_pcc)
 		return;
 
-	kthread_destroy_worker(kworker_fie);
+	cppc_fie_kworker_init();
+}
+
+static void cppc_freq_invariance_exit(void)
+{
+	if (kworker_fie)
+		kthread_destroy_worker(kworker_fie);
 }
 
 #else

drivers/cpufreq/cpufreq-dt-platdev.c

@@ -147,6 +147,8 @@ static const struct of_device_id blocklist[] __initconst = {
 	{ .compatible = "nvidia,tegra30", },
 	{ .compatible = "nvidia,tegra114", },
 	{ .compatible = "nvidia,tegra124", },
+	{ .compatible = "nvidia,tegra186", },
+	{ .compatible = "nvidia,tegra194", },
 	{ .compatible = "nvidia,tegra210", },
 	{ .compatible = "nvidia,tegra234", },
 
@@ -169,8 +171,11 @@ static const struct of_device_id blocklist[] __initconst = {
 	{ .compatible = "qcom,sdm845", },
 	{ .compatible = "qcom,sdx75", },
 	{ .compatible = "qcom,sm6115", },
+	{ .compatible = "qcom,sm6125", },
+	{ .compatible = "qcom,sm6150", },
 	{ .compatible = "qcom,sm6350", },
 	{ .compatible = "qcom,sm6375", },
+	{ .compatible = "qcom,sm7125", },
 	{ .compatible = "qcom,sm7225", },
 	{ .compatible = "qcom,sm7325", },
 	{ .compatible = "qcom,sm8150", },
@@ -191,6 +196,7 @@ static const struct of_device_id blocklist[] __initconst = {
 	{ .compatible = "ti,am625", },
 	{ .compatible = "ti,am62a7", },
 	{ .compatible = "ti,am62d2", },
+	{ .compatible = "ti,am62l3", },
 	{ .compatible = "ti,am62p5", },
 
 	{ .compatible = "qcom,ipq5332", },

drivers/cpufreq/rcpufreq_dt.rs

@@ -3,7 +3,6 @@
 //! Rust based implementation of the cpufreq-dt driver.
 
 use kernel::{
-    c_str,
     clk::Clk,
     cpu, cpufreq,
     cpumask::CpumaskVar,
@@ -52,7 +51,7 @@ impl opp::ConfigOps for CPUFreqDTDriver {}
 
 #[vtable]
 impl cpufreq::Driver for CPUFreqDTDriver {
-    const NAME: &'static CStr = c_str!("cpufreq-dt");
+    const NAME: &'static CStr = c"cpufreq-dt";
     const FLAGS: u16 = cpufreq::flags::NEED_INITIAL_FREQ_CHECK | cpufreq::flags::IS_COOLING_DEV;
     const BOOST_ENABLED: bool = true;
 
@@ -197,7 +196,7 @@ kernel::of_device_table!(
     OF_TABLE,
     MODULE_OF_TABLE,
     <CPUFreqDTDriver as platform::Driver>::IdInfo,
-    [(of::DeviceId::new(c_str!("operating-points-v2")), ())]
+    [(of::DeviceId::new(c"operating-points-v2"), ())]
 );
 
 impl platform::Driver for CPUFreqDTDriver {

drivers/cpufreq/scmi-cpufreq.c

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * System Control and Power Interface (SCMI) based CPUFreq Interface driver
+ * System Control and Management Interface (SCMI) based CPUFreq Interface driver
  *
  * Copyright (C) 2018-2021 ARM Ltd.
  * Sudeep Holla <sudeep.holla@arm.com>
@@ -101,6 +101,7 @@ static int scmi_cpu_domain_id(struct device *cpu_dev)
 			return -EINVAL;
 	}
 
+	of_node_put(domain_id.np);
 	return domain_id.args[0];
 }