1 files changed, 89 insertions, 75 deletions

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index 9eac77c4f294..7e8042efedd1 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/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
@@ -831,14 +863,13 @@ static ssize_t store_auto_select(struct cpufreq_policy *policy,
 	return count;
 }
 
-static ssize_t show_auto_act_window(struct cpufreq_policy *policy, char *buf)
+static ssize_t cppc_cpufreq_sysfs_show_u64(unsigned int cpu,
+					   int (*get_func)(int, u64 *),
+					   char *buf)
 {
 	u64 val;
-	int ret;
+	int ret = get_func((int)cpu, &val);
 
-	ret = cppc_get_auto_act_window(policy->cpu, &val);
-
-	/* show "<unsupported>" when this register is not supported by cpc */
 	if (ret == -EOPNOTSUPP)
 		return sysfs_emit(buf, "<unsupported>\n");
 
@@ -848,56 +879,39 @@ static ssize_t show_auto_act_window(struct cpufreq_policy *policy, char *buf)
 	return sysfs_emit(buf, "%llu\n", val);
 }
 
-static ssize_t store_auto_act_window(struct cpufreq_policy *policy,
-				     const char *buf, size_t count)
+static ssize_t cppc_cpufreq_sysfs_store_u64(unsigned int cpu,
+					    int (*set_func)(int, u64),
+					    const char *buf, size_t count)
 {
-	u64 usec;
+	u64 val;
 	int ret;
 
-	ret = kstrtou64(buf, 0, &usec);
+	ret = kstrtou64(buf, 0, &val);
 	if (ret)
 		return ret;
 
-	ret = cppc_set_auto_act_window(policy->cpu, usec);
-	if (ret)
-		return ret;
+	ret = set_func((int)cpu, val);
 
-	return count;
+	return ret ? ret : count;
 }
 
-static ssize_t show_energy_performance_preference_val(struct cpufreq_policy *policy, char *buf)
-{
-	u64 val;
-	int ret;
-
-	ret = cppc_get_epp_perf(policy->cpu, &val);
-
-	/* show "<unsupported>" when this register is not supported by cpc */
-	if (ret == -EOPNOTSUPP)
-		return sysfs_emit(buf, "<unsupported>\n");
-
-	if (ret)
-		return ret;
-
-	return sysfs_emit(buf, "%llu\n", val);
+#define CPPC_CPUFREQ_ATTR_RW_U64(_name, _get_func, _set_func)		\
+static ssize_t show_##_name(struct cpufreq_policy *policy, char *buf)	\
+{									\
+	return cppc_cpufreq_sysfs_show_u64(policy->cpu, _get_func, buf);\
+}									\
+static ssize_t store_##_name(struct cpufreq_policy *policy,		\
+			     const char *buf, size_t count)		\
+{									\
+	return cppc_cpufreq_sysfs_store_u64(policy->cpu, _set_func,	\
+					    buf, count);		\
 }
 
-static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
-						       const char *buf, size_t count)
-{
-	u64 val;
-	int ret;
-
-	ret = kstrtou64(buf, 0, &val);
-	if (ret)
-		return ret;
-
-	ret = cppc_set_epp(policy->cpu, val);
-	if (ret)
-		return ret;
+CPPC_CPUFREQ_ATTR_RW_U64(auto_act_window, cppc_get_auto_act_window,
+			 cppc_set_auto_act_window)
 
-	return count;
-}
+CPPC_CPUFREQ_ATTR_RW_U64(energy_performance_preference_val,
+			 cppc_get_epp_perf, cppc_set_epp)
 
 cpufreq_freq_attr_ro(freqdomain_cpus);
 cpufreq_freq_attr_rw(auto_select);