NVIDIA: VR: SAUCE: cpufreq: Remove driver default policy->min/max init

Prior to [1], drivers were setting policy->min/max and
the value was used as a QoS constraint. After that change,
the values were only temporarily used: cpufreq_set_policy()
ultimately overriding them through:
cpufreq_policy_online()
\-cpufreq_init_policy()
  \-cpufreq_set_policy()
    \-/* Set policy->min/max */

This patch reinstate the initial behaviour. This will allow
drivers to request min/max QoS frequencies if desired.
For instance, the cppc driver advertises a lowest non-linear
frequency, which should be used as a min QoS value.

To avoid having drivers setting policy->min/max to default
values which are considered as QoS values (i.e. the reason
why [1] was introduced), remove the initialization of
policy->min/max in .init() callbacks wherever the
policy->min/max values are identical to the
policy->cpuinfo.min/max_freq.

Indeed, the previous patch ("cpufreq: Set default
policy->min/max values for all drivers") makes this initialization
redundant.

The only drivers where these values are different are:
- gx-suspmod.c (min)
- cppc-cpufreq.c (min)
- longrun.c

[1]
commit 521223d ("cpufreq: Fix initialization of min and
max frequency QoS requests")

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
(backported from https://lore.kernel.org/lkml/20260511135538.522653-4-pierre.gondois@arm.com/)
[sforshee: adjustments to amd-pstate for missing max_freq caching patch]
Signed-off-by: Seth Forshee <sforshee@nvidia.com>

Author: pierregondois

drivers/cpufreq/amd-pstate.c

@@ -1001,12 +1001,10 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
 
 	perf = READ_ONCE(cpudata->perf);
 
-	policy->cpuinfo.min_freq = policy->min = perf_to_freq(perf,
-							      cpudata->nominal_freq,
-							      perf.lowest_perf);
-	policy->cpuinfo.max_freq = policy->max = perf_to_freq(perf,
-							      cpudata->nominal_freq,
-							      perf.highest_perf);
+	policy->cpuinfo.min_freq = perf_to_freq(perf, cpudata->nominal_freq,
+						perf.lowest_perf);
+	policy->cpuinfo.max_freq = perf_to_freq(perf, cpudata->nominal_freq,
+						perf.highest_perf);
 
 	ret = amd_pstate_cppc_enable(policy);
 	if (ret)
@@ -1490,12 +1488,10 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
 
 	perf = READ_ONCE(cpudata->perf);
 
-	policy->cpuinfo.min_freq = policy->min = perf_to_freq(perf,
-							      cpudata->nominal_freq,
-							      perf.lowest_perf);
-	policy->cpuinfo.max_freq = policy->max = perf_to_freq(perf,
-							      cpudata->nominal_freq,
-							      perf.highest_perf);
+	policy->cpuinfo.min_freq = perf_to_freq(perf, cpudata->nominal_freq,
+						perf.lowest_perf);
+	policy->cpuinfo.max_freq = perf_to_freq(perf, cpudata->nominal_freq,
+						perf.highest_perf);
 	policy->driver_data = cpudata;
 
 	ret = amd_pstate_cppc_enable(policy);

drivers/cpufreq/cppc_cpufreq.c

@@ -640,16 +640,15 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	 * Section 8.4.7.1.1.5 of ACPI 6.1 spec)
 	 */
 	policy->min = cppc_perf_to_khz(caps, caps->lowest_nonlinear_perf);
-	policy->max = cppc_perf_to_khz(caps, policy->boost_enabled ?
-						caps->highest_perf : caps->nominal_perf);
 
 	/*
 	 * Set cpuinfo.min_freq to Lowest to make the full range of performance
 	 * available if userspace wants to use any perf between lowest & lowest
 	 * nonlinear perf
 	 */
 	policy->cpuinfo.min_freq = cppc_perf_to_khz(caps, caps->lowest_perf);
-	policy->cpuinfo.max_freq = policy->max;
+	policy->cpuinfo.max_freq = cppc_perf_to_khz(caps, policy->boost_enabled ?
+						    caps->highest_perf : caps->nominal_perf);
 
 	policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu);
 	policy->shared_type = cpu_data->shared_type;

drivers/cpufreq/cpufreq-nforce2.c

@@ -355,8 +355,8 @@ static int nforce2_cpu_init(struct cpufreq_policy *policy)
 		min_fsb = NFORCE2_MIN_FSB;
 
 	/* cpuinfo and default policy values */
-	policy->min = policy->cpuinfo.min_freq = min_fsb * fid * 100;
-	policy->max = policy->cpuinfo.max_freq = max_fsb * fid * 100;
+	policy->cpuinfo.min_freq = min_fsb * fid * 100;
+	policy->cpuinfo.max_freq = max_fsb * fid * 100;
 
 	return 0;
 }

drivers/cpufreq/freq_table.c

@@ -49,16 +49,15 @@ int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy)
 			max_freq = freq;
 	}
 
-	policy->min = policy->cpuinfo.min_freq = min_freq;
-	policy->max = max_freq;
+	policy->cpuinfo.min_freq = min_freq;
 	/*
 	 * If the driver has set its own cpuinfo.max_freq above max_freq, leave
 	 * it as is.
 	 */
 	if (policy->cpuinfo.max_freq < max_freq)
-		policy->max = policy->cpuinfo.max_freq = max_freq;
+		policy->cpuinfo.max_freq = max_freq;
 
-	if (policy->min == ~0)
+	if (min_freq == ~0)
 		return -EINVAL;
 	else
 		return 0;

drivers/cpufreq/gx-suspmod.c

@@ -421,7 +421,7 @@ static int cpufreq_gx_cpu_init(struct cpufreq_policy *policy)
 		policy->min = maxfreq / max_duration;
 	else
 		policy->min = maxfreq / POLICY_MIN_DIV;
-	policy->max = maxfreq;
+
 	policy->cpuinfo.min_freq = maxfreq / max_duration;
 	policy->cpuinfo.max_freq = maxfreq;
 

drivers/cpufreq/intel_pstate.c

@@ -3080,9 +3080,6 @@ static int __intel_pstate_cpu_init(struct cpufreq_policy *policy)
 	policy->cpuinfo.max_freq = READ_ONCE(global.no_turbo) ?
 			cpu->pstate.max_freq : cpu->pstate.turbo_freq;
 
-	policy->min = policy->cpuinfo.min_freq;
-	policy->max = policy->cpuinfo.max_freq;
-
 	intel_pstate_init_acpi_perf_limits(policy);
 
 	policy->fast_switch_possible = true;

drivers/cpufreq/pcc-cpufreq.c

@@ -551,13 +551,11 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 		goto out;
 	}
 
-	policy->max = policy->cpuinfo.max_freq =
-		ioread32(&pcch_hdr->nominal) * 1000;
-	policy->min = policy->cpuinfo.min_freq =
-		ioread32(&pcch_hdr->minimum_frequency) * 1000;
+	policy->cpuinfo.max_freq = ioread32(&pcch_hdr->nominal) * 1000;
+	policy->cpuinfo.min_freq = ioread32(&pcch_hdr->minimum_frequency) * 1000;
 
-	pr_debug("init: policy->max is %d, policy->min is %d\n",
-		policy->max, policy->min);
+	pr_debug("init: max_freq is %d, min_freq is %d\n",
+		 policy->cpuinfo.max_freq, policy->cpuinfo.min_freq);
 out:
 	return result;
 }

drivers/cpufreq/pxa3xx-cpufreq.c

@@ -185,9 +185,8 @@ static int pxa3xx_cpufreq_init(struct cpufreq_policy *policy)
 	int ret = -EINVAL;
 
 	/* set default policy and cpuinfo */
-	policy->min = policy->cpuinfo.min_freq = 104000;
-	policy->max = policy->cpuinfo.max_freq =
-		(cpu_is_pxa320()) ? 806000 : 624000;
+	policy->cpuinfo.min_freq = 104000;
+	policy->cpuinfo.max_freq = (cpu_is_pxa320()) ? 806000 : 624000;
 	policy->cpuinfo.transition_latency = 1000; /* FIXME: 1 ms, assumed */
 
 	if (cpu_is_pxa300() || cpu_is_pxa310())

drivers/cpufreq/sh-cpufreq.c

@@ -124,10 +124,8 @@ static int sh_cpufreq_cpu_init(struct cpufreq_policy *policy)
 		dev_notice(dev, "no frequency table found, falling back "
 			   "to rate rounding.\n");
 
-		policy->min = policy->cpuinfo.min_freq =
-			(clk_round_rate(cpuclk, 1) + 500) / 1000;
-		policy->max = policy->cpuinfo.max_freq =
-			(clk_round_rate(cpuclk, ~0UL) + 500) / 1000;
+		policy->cpuinfo.min_freq = (clk_round_rate(cpuclk, 1) + 500) / 1000;
+		policy->cpuinfo.max_freq = (clk_round_rate(cpuclk, ~0UL) + 500) / 1000;
 	}
 
 	return 0;

drivers/cpufreq/virtual-cpufreq.c

@@ -164,10 +164,7 @@ static int virt_cpufreq_get_freq_info(struct cpufreq_policy *policy)
 		policy->cpuinfo.min_freq = 1;
 		policy->cpuinfo.max_freq = virt_cpufreq_get_perftbl_entry(policy->cpu, 0);
 
-		policy->min = policy->cpuinfo.min_freq;
-		policy->max = policy->cpuinfo.max_freq;
-
-		policy->cur = policy->max;
+		policy->cur = policy->cpuinfo.max_freq;
 		return 0;
 	}