ACPI: CPPC: Add ACPI disabled check to acpi_cpc_valid()

Make acpi_cpc_valid() check if ACPI is disabled, so that its callers
don't need to check that separately.  This will also cause the AMD
pstate driver to refuse to load right away when ACPI is disabled.

Also update the warning message in amd_pstate_init() to mention the
ACPI disabled case for completeness.

Signed-off-by: Perry Yuan <[email protected]>
[ rjw: Subject edits, new changelog ]
Signed-off-by: Rafael J. Wysocki <[email protected]>

Author: Perry Yuan

drivers/acpi/cppc_acpi.c

@@ -424,6 +424,9 @@ bool acpi_cpc_valid(void)
 	struct cpc_desc *cpc_ptr;
 	int cpu;
 
+	if (acpi_disabled)
+		return false;
+
 	for_each_present_cpu(cpu) {
 		cpc_ptr = per_cpu(cpc_desc_ptr, cpu);
 		if (!cpc_ptr)

drivers/base/arch_topology.c

@@ -353,7 +353,7 @@ void topology_init_cpu_capacity_cppc(void)
 	struct cppc_perf_caps perf_caps;
 	int cpu;
 
-	if (likely(acpi_disabled || !acpi_cpc_valid()))
+	if (likely(!acpi_cpc_valid()))
 		return;
 
 	raw_capacity = kcalloc(num_possible_cpus(), sizeof(*raw_capacity),

drivers/cpufreq/amd-pstate.c

@@ -673,7 +673,7 @@ static int __init amd_pstate_init(void)
 		return -ENODEV;
 
 	if (!acpi_cpc_valid()) {
-		pr_debug("the _CPC object is not present in SBIOS\n");
+		pr_warn_once("the _CPC object is not present in SBIOS or ACPI disabled\n");
 		return -ENODEV;
 	}
 

drivers/cpufreq/cppc_cpufreq.c

@@ -947,7 +947,7 @@ static int __init cppc_cpufreq_init(void)
 {
 	int ret;
 
-	if ((acpi_disabled) || !acpi_cpc_valid())
+	if (!acpi_cpc_valid())
 		return -ENODEV;
 
 	cppc_check_hisi_workaround();