1 files changed, 52 insertions, 0 deletions

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index b5e54f2da53d..0d92d0f915e9 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -491,6 +491,58 @@ static void acpi_processor_remove(struct acpi_device *device)
 }
 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
 
+#ifdef CONFIG_X86
+static bool acpi_hwp_native_thermal_lvt_set;
+static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
+                                                          u32 lvl,
+                                                          void *context,
+                                                          void **rv)
+{
+        u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
+        u32 capbuf[2];
+        struct acpi_osc_context osc_context = {
+                .uuid_str = sb_uuid_str,
+                .rev = 1,
+                .cap.length = 8,
+                .cap.pointer = capbuf,
+        };
+
+        if (acpi_hwp_native_thermal_lvt_set)
+                return AE_CTRL_TERMINATE;
+
+        capbuf[0] = 0x0000;
+        capbuf[1] = 0x1000; /* set bit 12 */
+
+        if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
+                if (osc_context.ret.pointer && osc_context.ret.length > 1) {
+                        u32 *capbuf_ret = osc_context.ret.pointer;
+
+                        if (capbuf_ret[1] & 0x1000) {
+                                acpi_handle_info(handle,
+                                        "_OSC native thermal LVT Acked\n");
+                                acpi_hwp_native_thermal_lvt_set = true;
+                        }
+                }
+                kfree(osc_context.ret.pointer);
+        }
+
+        return AE_OK;
+}
+
+void __init acpi_early_processor_osc(void)
+{
+        if (boot_cpu_has(X86_FEATURE_HWP)) {
+                acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
+                                    ACPI_UINT32_MAX,
+                                    acpi_hwp_native_thermal_lvt_osc,
+                                    NULL, NULL, NULL);
+                acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
+                                 acpi_hwp_native_thermal_lvt_osc,
+                                 NULL, NULL);
+        }
+}
+#endif
+
 /*
  * The following ACPI IDs are known to be suitable for representing as
  * processor devices.