cpufreq: intel_pstate: Clean up frequency computations

Notice that some computations related to frequency in intel_pstate
can be simplified if (a) intel_pstate_get_hwp_max() updates the
relevant members of struct cpudata by itself and (b) the "turbo
disabled" check is moved from it to its callers, so modify the code
accordingly and while at it rename intel_pstate_get_hwp_max() to
intel_pstate_get_hwp_cap() which better reflects its purpose and
provide a simplified variat of it, __intel_pstate_get_hwp_cap(),
suitable for the initialization path.

No intentional functional impact.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NChen Yu <yu.c.chen@intel.com>

drivers/cpufreq/intel_pstate.c

@@ -819,19 +819,21 @@ static struct freq_attr *hwp_cpufreq_attrs[] = {
 	NULL,
 };
 
-static void intel_pstate_get_hwp_max(struct cpudata *cpu, int *phy_max,
-				     int *current_max)
+static void __intel_pstate_get_hwp_cap(struct cpudata *cpu)
 {
 	u64 cap;
 
 	rdmsrl_on_cpu(cpu->cpu, MSR_HWP_CAPABILITIES, &cap);
 	WRITE_ONCE(cpu->hwp_cap_cached, cap);
-	if (global.no_turbo || global.turbo_disabled)
-		*current_max = HWP_GUARANTEED_PERF(cap);
-	else
-		*current_max = HWP_HIGHEST_PERF(cap);
+	cpu->pstate.max_pstate = HWP_GUARANTEED_PERF(cap);
+	cpu->pstate.turbo_pstate = HWP_HIGHEST_PERF(cap);
+}
 
-	*phy_max = HWP_HIGHEST_PERF(cap);
+static void intel_pstate_get_hwp_cap(struct cpudata *cpu)
+{
+	__intel_pstate_get_hwp_cap(cpu);
+	cpu->pstate.max_freq = cpu->pstate.max_pstate * cpu->pstate.scaling;
+	cpu->pstate.turbo_freq = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
 }
 
 static void intel_pstate_hwp_set(unsigned int cpu)
@@ -1195,12 +1197,13 @@ static ssize_t store_no_turbo(struct kobject *a, struct kobj_attribute *b,
 
 static void update_qos_request(enum freq_qos_req_type type)
 {
-	int max_state, turbo_max, freq, i, perf_pct;
 	struct freq_qos_request *req;
 	struct cpufreq_policy *policy;
+	int i;
 
 	for_each_possible_cpu(i) {
 		struct cpudata *cpu = all_cpu_data[i];
+		unsigned int freq, perf_pct;
 
 		policy = cpufreq_cpu_get(i);
 		if (!policy)
@@ -1213,9 +1216,7 @@ static void update_qos_request(enum freq_qos_req_type type)
 			continue;
 
 		if (hwp_active)
-			intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
-		else
-			turbo_max = cpu->pstate.turbo_pstate;
+			intel_pstate_get_hwp_cap(cpu);
 
 		if (type == FREQ_QOS_MIN) {
 			perf_pct = global.min_perf_pct;
@@ -1224,8 +1225,7 @@ static void update_qos_request(enum freq_qos_req_type type)
 			perf_pct = global.max_perf_pct;
 		}
 
-		freq = DIV_ROUND_UP(turbo_max * perf_pct, 100);
-		freq *= cpu->pstate.scaling;
+		freq = DIV_ROUND_UP(cpu->pstate.turbo_freq * perf_pct, 100);
 
 		if (freq_qos_update_request(req, freq) < 0)
 			pr_warn("Failed to update freq constraint: CPU%d\n", i);
@@ -1715,21 +1715,17 @@ static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 {
 	cpu->pstate.min_pstate = pstate_funcs.get_min();
 	cpu->pstate.max_pstate_physical = pstate_funcs.get_max_physical();
-	cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
 	cpu->pstate.scaling = pstate_funcs.get_scaling();
 
 	if (hwp_active && !hwp_mode_bdw) {
-		unsigned int phy_max, current_max;
-
-		intel_pstate_get_hwp_max(cpu, &phy_max, &current_max);
-		cpu->pstate.turbo_freq = phy_max * cpu->pstate.scaling;
-		cpu->pstate.turbo_pstate = phy_max;
-		cpu->pstate.max_pstate = HWP_GUARANTEED_PERF(READ_ONCE(cpu->hwp_cap_cached));
+		__intel_pstate_get_hwp_cap(cpu);
 	} else {
-		cpu->pstate.turbo_freq = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
 		cpu->pstate.max_pstate = pstate_funcs.get_max();
+		cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
 	}
+
 	cpu->pstate.max_freq = cpu->pstate.max_pstate * cpu->pstate.scaling;
+	cpu->pstate.turbo_freq = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
 
 	if (pstate_funcs.get_aperf_mperf_shift)
 		cpu->aperf_mperf_shift = pstate_funcs.get_aperf_mperf_shift();
@@ -2204,18 +2200,21 @@ static void intel_pstate_update_perf_limits(struct cpudata *cpu,
 	int max_freq;
 
 	/*
-	 * HWP needs some special consideration, because on BDX the
-	 * HWP_REQUEST uses abstract value to represent performance
-	 * rather than pure ratios.
+	 * HWP needs some special consideration, because HWP_REQUEST uses
+	 * abstract values to represent performance rather than pure ratios.
 	 */
-	if (hwp_active) {
-		intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
+	if (hwp_active)
+		intel_pstate_get_hwp_cap(cpu);
+
+	if (global.no_turbo || global.turbo_disabled) {
+		max_state = cpu->pstate.max_pstate;
+		max_freq = cpu->pstate.max_freq;
 	} else {
-		max_state = global.no_turbo || global.turbo_disabled ?
-			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
-		turbo_max = cpu->pstate.turbo_pstate;
+		max_state = cpu->pstate.turbo_pstate;
+		max_freq = cpu->pstate.turbo_freq;
 	}
-	max_freq = max_state * cpu->pstate.scaling;
+
+	turbo_max = cpu->pstate.turbo_pstate;
 
 	max_policy_perf = max_state * policy_max / max_freq;
 	if (policy_max == policy_min) {
@@ -2322,10 +2321,9 @@ static void intel_pstate_verify_cpu_policy(struct cpudata *cpu,
 
 	update_turbo_state();
 	if (hwp_active) {
-		int max_state, turbo_max;
-
-		intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
-		max_freq = max_state * cpu->pstate.scaling;
+		intel_pstate_get_hwp_cap(cpu);
+		max_freq = global.no_turbo || global.turbo_disabled ?
+				cpu->pstate.max_freq : cpu->pstate.turbo_freq;
 	} else {
 		max_freq = intel_pstate_get_max_freq(cpu);
 	}
@@ -2416,25 +2414,15 @@ static int __intel_pstate_cpu_init(struct cpufreq_policy *policy)
 	cpu->max_perf_ratio = 0xFF;
 	cpu->min_perf_ratio = 0;
 
-	policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
-	policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
-
 	/* cpuinfo and default policy values */
 	policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
 	update_turbo_state();
 	global.turbo_disabled_mf = global.turbo_disabled;
 	policy->cpuinfo.max_freq = global.turbo_disabled ?
-			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
-	policy->cpuinfo.max_freq *= cpu->pstate.scaling;
-
-	if (hwp_active) {
-		unsigned int max_freq;
-
-		max_freq = global.turbo_disabled ?
 			cpu->pstate.max_freq : cpu->pstate.turbo_freq;
-		if (max_freq < policy->cpuinfo.max_freq)
-			policy->cpuinfo.max_freq = max_freq;
-	}
+
+	policy->min = policy->cpuinfo.min_freq;
+	policy->max = policy->cpuinfo.max_freq;
 
 	intel_pstate_init_acpi_perf_limits(policy);
 
@@ -2683,10 +2671,10 @@ static void intel_cpufreq_adjust_perf(unsigned int cpunum,
 
 static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy)
 {
-	int max_state, turbo_max, min_freq, max_freq, ret;
 	struct freq_qos_request *req;
 	struct cpudata *cpu;
 	struct device *dev;
+	int ret, freq;
 
 	dev = get_cpu_device(policy->cpu);
 	if (!dev)
@@ -2711,30 +2699,31 @@ static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	if (hwp_active) {
 		u64 value;
 
-		intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
 		policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY_HWP;
+
+		intel_pstate_get_hwp_cap(cpu);
+
 		rdmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, &value);
 		WRITE_ONCE(cpu->hwp_req_cached, value);
+
 		cpu->epp_cached = intel_pstate_get_epp(cpu, value);
 	} else {
-		turbo_max = cpu->pstate.turbo_pstate;
 		policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY;
 	}
 
-	min_freq = DIV_ROUND_UP(turbo_max * global.min_perf_pct, 100);
-	min_freq *= cpu->pstate.scaling;
-	max_freq = DIV_ROUND_UP(turbo_max * global.max_perf_pct, 100);
-	max_freq *= cpu->pstate.scaling;
+	freq = DIV_ROUND_UP(cpu->pstate.turbo_freq * global.min_perf_pct, 100);
 
 	ret = freq_qos_add_request(&policy->constraints, req, FREQ_QOS_MIN,
-				   min_freq);
+				   freq);
 	if (ret < 0) {
 		dev_err(dev, "Failed to add min-freq constraint (%d)\n", ret);
 		goto free_req;
 	}
 
+	freq = DIV_ROUND_UP(cpu->pstate.turbo_freq * global.max_perf_pct, 100);
+
 	ret = freq_qos_add_request(&policy->constraints, req + 1, FREQ_QOS_MAX,
-				   max_freq);
+				   freq);
 	if (ret < 0) {
 		dev_err(dev, "Failed to add max-freq constraint (%d)\n", ret);
 		goto remove_min_req;