LoongArch: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval

As a step towards unifying the interface for retrieving ACPI CPU UID
across architectures, introduce a new function acpi_get_cpu_uid() for
loongarch. While at it, add input validation to make the code more
robust.

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Link: https://patch.msgid.link/20260401081640.26875-3-fengchengwen@huawei.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/arch/loongarch/include/asm/acpi.h b/arch/loongarch/include/asm/acpi.h
index 7376840fa9f78a657188da556d31b12ce89ef194..8bb101b4557e17535538600f13b1721df91eec98 100644 (file)
--- a/arch/loongarch/include/asm/acpi.h
+++ b/arch/loongarch/include/asm/acpi.h
@@ -44,6 +44,7 @@ static inline u32 get_acpi_id_for_cpu(unsigned int cpu)
 {
        return acpi_core_pic[cpu_logical_map(cpu)].processor_id;
 }
+int acpi_get_cpu_uid(unsigned int cpu, u32 *uid);
 
 #endif /* !CONFIG_ACPI */
 

diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c
index 1367ca759468f9c29460239353111874d05a8439..058f0dbe8e8f97c6add3da9ce995c53a46071015 100644 (file)
--- a/arch/loongarch/kernel/acpi.c
+++ b/arch/loongarch/kernel/acpi.c
@@ -385,3 +385,12 @@ int acpi_unmap_cpu(int cpu)
 EXPORT_SYMBOL(acpi_unmap_cpu);
 
 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
+
+int acpi_get_cpu_uid(unsigned int cpu, u32 *uid)
+{
+       if (cpu >= nr_cpu_ids)
+               return -EINVAL;
+       *uid = acpi_core_pic[cpu_logical_map(cpu)].processor_id;
+       return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_get_cpu_uid);