X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Fprocess.c;h=7fc4d5b0a6a0f99a4d1d9c4df685a5a4d3a135bb;hp=7dceea947232f5739b7844c10ba9c2b22f336e95;hb=eda3d8f5604860aae1bb9996bb5efc4213778369;hpb=84c3d4aaec3338201b449034beac41635866bddf

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 7dceea947232..7fc4d5b0a6a0 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -7,8 +7,15 @@
 #include <linux/module.h>
 #include <linux/pm.h>
 #include <linux/clockchips.h>
+#include <asm/system.h>
+
+unsigned long idle_halt;
+EXPORT_SYMBOL(idle_halt);
+unsigned long idle_nomwait;
+EXPORT_SYMBOL(idle_nomwait);
 
 struct kmem_cache *task_xstate_cachep;
+static int force_mwait __cpuinitdata;
 
 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
 {
@@ -193,6 +200,7 @@ static void poll_idle(void)
  *
  * idle=mwait overrides this decision and forces the usage of mwait.
  */
+static int __cpuinitdata force_mwait;
 
 #define MWAIT_INFO			0x05
 #define MWAIT_ECX_EXTENDED_INFO		0x01
@@ -320,12 +328,35 @@ void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
 
 static int __init idle_setup(char *str)
 {
+	if (!str)
+		return -EINVAL;
+
 	if (!strcmp(str, "poll")) {
 		printk("using polling idle threads.\n");
 		pm_idle = poll_idle;
 	} else if (!strcmp(str, "mwait"))
 		force_mwait = 1;
-	else
+	else if (!strcmp(str, "halt")) {
+		/*
+		 * When the boot option of idle=halt is added, halt is
+		 * forced to be used for CPU idle. In such case CPU C2/C3
+		 * won't be used again.
+		 * To continue to load the CPU idle driver, don't touch
+		 * the boot_option_idle_override.
+		 */
+		pm_idle = default_idle;
+		idle_halt = 1;
+		return 0;
+	} else if (!strcmp(str, "nomwait")) {
+		/*
+		 * If the boot option of "idle=nomwait" is added,
+		 * it means that mwait will be disabled for CPU C2/C3
+		 * states. In such case it won't touch the variable
+		 * of boot_option_idle_override.
+		 */
+		idle_nomwait = 1;
+		return 0;
+	} else
 		return -1;
 
 	boot_option_idle_override = 1;