[PATCH v9 07/19] ACPI: processor: Add acpi_get_processor_handle() helper

Jonathan Cameron
2024-04-30T14:28:13Z

If CONFIG_ACPI_PROCESSOR provide a helper to retrieve the
acpi_handle for a given CPU allowing access to methods
in DSDT.

Tested-by: Miguel Luis <miguel.luis@oracle.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

---
v9: Tags
---
drivers/acpi/acpi_processor.c | 11 +++++++++++
include/linux/acpi.h | 7 +++++++
2 files changed, 18 insertions(+)

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 4a79b42d649e..e8cbe0e40dd0 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -35,6 +35,17 @@ EXPORT_PER_CPU_SYMBOL(processors);
struct acpi_processor_errata errata __read_mostly;
EXPORT_SYMBOL_GPL(errata);

+acpi_handle acpi_get_processor_handle(int cpu)
+{
+ struct acpi_processor *pr;
+
+ pr = per_cpu(processors, cpu);
+ if (pr)
+ return pr->handle;
+
+ return NULL;
+}
+
static int acpi_processor_errata_piix4(struct pci_dev *dev)
{
u8 value1 = 0;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 34829f2c517a..9844a3f9c4e5 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -309,6 +309,8 @@ int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id,
int acpi_unmap_cpu(int cpu);
#endif /* CONFIG_ACPI_HOTPLUG_CPU */

+acpi_handle acpi_get_processor_handle(int cpu);
+
#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr);
#endif
@@ -1077,6 +1079,11 @@ static inline bool acpi_sleep_state_supported(u8 sleep_state)
return false;
}

+static inline acpi_handle acpi_get_processor_handle(int cpu)
+{
+ return NULL;
+}
+
#endif /* !CONFIG_ACPI */

extern void arch_post_acpi_subsys_init(void);
--
2.39.2