diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 736d45602886ea7b08024f246f06e9c7c6dc1a05..826b6e1483166d499ed9de7c2240dc35eb7d990a 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -199,6 +199,10 @@ and is between 256 and 4096 characters. It is defined in the file
 			acpi_display_output=video
 			See above.
 
+	acpi_early_pdc_eval	[HW,ACPI] Evaluate processor _PDC methods
+				early. Needed on some platforms to properly
+				initialize the EC.
+
 	acpi_irq_balance [HW,ACPI]
 			ACPI will balance active IRQs
 			default in APIC mode
diff --git a/drivers/acpi/processor_pdc.c b/drivers/acpi/processor_pdc.c
index 7247819dbd80b0679af19bb17b152b4ba1f7dee9..3bbafe9576aecfcee2fbb311c69991dd415b6f5a 100644
--- a/drivers/acpi/processor_pdc.c
+++ b/drivers/acpi/processor_pdc.c
@@ -151,6 +151,13 @@ static int set_early_pdc_optin(const struct dmi_system_id *id)
 	return 0;
 }
 
+static int param_early_pdc_optin(char *s)
+{
+	early_pdc_optin = 1;
+	return 1;
+}
+__setup("acpi_early_pdc_eval", param_early_pdc_optin);
+
 static struct dmi_system_id __cpuinitdata early_pdc_optin_table[] = {
 	{
 	set_early_pdc_optin, "HP Envy", {