---

yaml
---
r: 117271
b: refs/heads/master
c: 910dfae
h: refs/heads/master
i:
  117269: 0619ba5
  117267: e687ae0
  117263: 9d25993
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a0ad05c75aa362c91f4d9cd91ff375a739574dd8
+refs/heads/master: 910dfae298f7b3dae0e9a52736182a3b0559ca35

trunk/drivers/acpi/processor_perflib.c

@@ -38,6 +38,7 @@
 
 #include <asm/uaccess.h>
 #endif
+#include <asm/cpufeature.h>
 
 #include <acpi/acpi_bus.h>
 #include <acpi/processor.h>
@@ -334,7 +335,6 @@ static int acpi_processor_get_performance_info(struct acpi_processor *pr)
 	acpi_status status = AE_OK;
 	acpi_handle handle = NULL;
 
-
 	if (!pr || !pr->performance || !pr->handle)
 		return -EINVAL;
 
@@ -347,13 +347,25 @@ static int acpi_processor_get_performance_info(struct acpi_processor *pr)
 
 	result = acpi_processor_get_performance_control(pr);
 	if (result)
-		return result;
+		goto update_bios;
 
 	result = acpi_processor_get_performance_states(pr);
 	if (result)
-		return result;
+		goto update_bios;
 
 	return 0;
+
+	/*
+	 * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that
+	 * the BIOS is older than the CPU and does not know its frequencies
+	 */
+ update_bios:
+	if (ACPI_SUCCESS(acpi_get_handle(pr->handle, "_PPC", &handle))){
+		if(boot_cpu_has(X86_FEATURE_EST))
+			printk(KERN_WARNING FW_BUG "BIOS needs update for CPU "
+			       "frequency support\n");
+	}
+	return result;
 }
 
 int acpi_processor_notify_smm(struct module *calling_module)