Add option "xen_processor_pm" in xen to enable dom0 external Cx control.

Signed-off-by: Wei Gang <gang.wei@intel.com>

diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index cc54a4ac5f3cfbad3e50d1b388e8da2033c97969..400db8ad09c0d792ad4c0d62d8fb22f77a8caa13 100644 (file)
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -94,6 +94,11 @@ boolean_param("acpi_skip_timer_override", acpi_skip_timer_override);
 extern int skip_ioapic_setup;
 boolean_param("noapic", skip_ioapic_setup);
 
+/* **** Linux config option: propagated to domain0. */
+/* xen_processor_pm: xen control cstate. */
+static int xen_processor_pm;
+boolean_param("xen_processor_pm", xen_processor_pm);
+
 int early_boot = 1;
 
 cpumask_t cpu_present_map;
@@ -1008,6 +1013,8 @@ void __init __start_xen(unsigned long mbi_p)
             safe_strcat(dom0_cmdline, " acpi=");
             safe_strcat(dom0_cmdline, acpi_param);
         }
+        if ( xen_processor_pm && !strstr(dom0_cmdline, "xen_processor_pmbits=") )
+            safe_strcat(dom0_cmdline, " xen_processor_pmbits=1");
 
         cmdline = dom0_cmdline;
     }