APM idle: register apm_cpu_idle via cpuidle

Update APM to register its local idle routine with cpuidle.

This allows us to stop exporting pm_idle to modules on x86.

The Kconfig sub-option, APM_CPU_IDLE, now depends on on CPU_IDLE.

Compile-tested only.

Signed-off-by: Len Brown <len.brown@intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Jiri Kosina <jkosina@suse.cz>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 225543b..1b63586 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1912,6 +1912,7 @@ config APM_DO_ENABLE
          this feature.
 
 config APM_CPU_IDLE
+       depends on CPU_IDLE
        bool "Make CPU Idle calls when idle"
        ---help---
          Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.

diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index d65464e..9f4bc6a 100644 (file)
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -232,6 +232,7 @@
 #include <linux/acpi.h>
 #include <linux/syscore_ops.h>
 #include <linux/i8253.h>
+#include <linux/cpuidle.h>
 
 #include <asm/uaccess.h>
 #include <asm/desc.h>
@@ -360,13 +361,35 @@ struct apm_user {
  * idle percentage above which bios idle calls are done
  */
 #ifdef CONFIG_APM_CPU_IDLE
-#warning deprecated CONFIG_APM_CPU_IDLE will be deleted in 2012
 #define DEFAULT_IDLE_THRESHOLD 95
 #else
 #define DEFAULT_IDLE_THRESHOLD 100
 #endif
 #define DEFAULT_IDLE_PERIOD    (100 / 3)
 
+static int apm_cpu_idle(struct cpuidle_device *dev,
+                       struct cpuidle_driver *drv, int index);
+
+static struct cpuidle_driver apm_idle_driver = {
+       .name = "apm_idle",
+       .owner = THIS_MODULE,
+       .en_core_tk_irqen = 1,
+       .states = {
+               { /* entry 0 is for polling */ },
+               { /* entry 1 is for APM idle */
+                       .name = "APM",
+                       .desc = "APM idle",
+                       .flags = CPUIDLE_FLAG_TIME_VALID,
+                       .exit_latency = 250,    /* WAG */
+                       .target_residency = 500,        /* WAG */
+                       .enter = &apm_cpu_idle
+               },
+       },
+       .state_count = 2,
+};
+
+static struct cpuidle_device apm_cpuidle_device;
+
 /*
  * Local variables
  */
@@ -377,7 +400,6 @@ static struct {
 static int clock_slowed;
 static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
 static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
-static int set_pm_idle;
 static int suspends_pending;
 static int standbys_pending;
 static int ignore_sys_suspend;
@@ -884,8 +906,6 @@ static void apm_do_busy(void)
 #define IDLE_CALC_LIMIT        (HZ * 100)
 #define IDLE_LEAKY_MAX 16
 
-static void (*original_pm_idle)(void) __read_mostly;
-
 /**
  * apm_cpu_idle                -       cpu idling for APM capable Linux
  *
@@ -894,7 +914,8 @@ static void (*original_pm_idle)(void) __read_mostly;
  * Furthermore it calls the system default idle routine.
  */
 
-static void apm_cpu_idle(void)
+static int apm_cpu_idle(struct cpuidle_device *dev,
+       struct cpuidle_driver *drv, int index)
 {
        static int use_apm_idle; /* = 0 */
        static unsigned int last_jiffies; /* = 0 */
@@ -904,7 +925,6 @@ static void apm_cpu_idle(void)
        unsigned int jiffies_since_last_check = jiffies - last_jiffies;
        unsigned int bucket;
 
-       WARN_ONCE(1, "deprecated apm_cpu_idle will be deleted in 2012");
 recalc:
        if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
                use_apm_idle = 0;
@@ -950,10 +970,7 @@ recalc:
                                break;
                        }
                }
-               if (original_pm_idle)
-                       original_pm_idle();
-               else
-                       default_idle();
+               default_idle();
                local_irq_disable();
                jiffies_since_last_check = jiffies - last_jiffies;
                if (jiffies_since_last_check > idle_period)
@@ -963,7 +980,7 @@ recalc:
        if (apm_idle_done)
                apm_do_busy();
 
-       local_irq_enable();
+       return index;
 }
 
 /**
@@ -2381,9 +2398,9 @@ static int __init apm_init(void)
        if (HZ != 100)
                idle_period = (idle_period * HZ) / 100;
        if (idle_threshold < 100) {
-               original_pm_idle = pm_idle;
-               pm_idle  = apm_cpu_idle;
-               set_pm_idle = 1;
+               if (!cpuidle_register_driver(&apm_idle_driver))
+                       if (cpuidle_register_device(&apm_cpuidle_device))
+                               cpuidle_unregister_driver(&apm_idle_driver);
        }
 
        return 0;
@@ -2393,15 +2410,9 @@ static void __exit apm_exit(void)
 {
        int error;
 
-       if (set_pm_idle) {
-               pm_idle = original_pm_idle;
-               /*
-                * We are about to unload the current idle thread pm callback
-                * (pm_idle), Wait for all processors to update cached/local
-                * copies of pm_idle before proceeding.
-                */
-               kick_all_cpus_sync();
-       }
+       cpuidle_unregister_device(&apm_cpuidle_device);
+       cpuidle_unregister_driver(&apm_idle_driver);
+
        if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
            && (apm_info.connection_version > 0x0100)) {
                error = apm_engage_power_management(APM_DEVICE_ALL, 0);

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 2ed787f..f571a6e 100644 (file)
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -272,9 +272,6 @@ EXPORT_SYMBOL(boot_option_idle_override);
  * Powermanagement idle function, if any..
  */
 void (*pm_idle)(void);
-#ifdef CONFIG_APM_MODULE
-EXPORT_SYMBOL(pm_idle);
-#endif
 
 #ifndef CONFIG_SMP
 static inline void play_dead(void)