On 08/23/2013 08:46 AM, Wang Dongsheng-B40534 wrote:
>
>> diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
>> index 0e2cd5c..e805dcd 100644
>> --- a/drivers/cpuidle/Kconfig
>> +++ b/drivers/cpuidle/Kconfig
>
> Maybe drivers/cpuidle/Kconfig.powerpc is better? Like arm.
>
>> +obj-$(CONFIG_CPU_IDLE_IBM_POWER) += cpuidle-ibm-power.o
>> diff --git a/drivers/cpuidle/cpuidle-ibm-power.c
>> b/drivers/cpuidle/cpuidle-ibm-power.c
>> new file mode 100644
>> index 0000000..4ee5a94
>> --- /dev/null
>> +++ b/drivers/cpuidle/cpuidle-ibm-power.c
>> @@ -0,0 +1,304 @@
>> +/*
>> + * cpuidle-ibm-power - idle state cpuidle driver.
>> + * Adapted from drivers/idle/intel_idle.c and
>> + * drivers/acpi/processor_idle.c
>> + *
>> + */
>> +
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/moduleparam.h>
>> +#include <linux/cpuidle.h>
>> +#include <linux/cpu.h>
>> +#include <linux/notifier.h>
>> +
>> +#include <asm/paca.h>
>> +#include <asm/reg.h>
>> +#include <asm/machdep.h>
>> +#include <asm/firmware.h>
>> +#include <asm/runlatch.h>
>> +#include <asm/plpar_wrappers.h>
>> +
>> +struct cpuidle_driver power_idle_driver = {
>> + .name = "IBM-POWER-Idle",
>> + .owner = THIS_MODULE,
>> +};
>> +
>> +#define MAX_IDLE_STATE_COUNT 2
>> +
>> +static int max_idle_state = MAX_IDLE_STATE_COUNT - 1;
>
> Again, do not use the macro.
Wanting to re-use CPUIDLE_STATE_MAX macro, defined in linux/cpuidle.h
similar to what x86 uses. This is def scalable for various platforms ,
as demonstrated in drivers/idle/intel_idle.c
>
>> +static struct cpuidle_state *cpuidle_state_table;
>> +
>> +static inline void idle_loop_prolog(unsigned long *in_purr)
>> +{
>> + *in_purr = mfspr(SPRN_PURR);
>> + /*
>> + * Indicate to the HV that we are idle. Now would be
>> + * a good time to find other work to dispatch.
>> + */
>> + get_lppaca()->idle = 1;
>> +}
>> +
>> +static inline void idle_loop_epilog(unsigned long in_purr)
>> +{
>> + get_lppaca()->wait_state_cycles += mfspr(SPRN_PURR) - in_purr;
>> + get_lppaca()->idle = 0;
>> +}
>> +
>> +static int snooze_loop(struct cpuidle_device *dev,
>> + struct cpuidle_driver *drv,
>> + int index)
>> +{
>> + unsigned long in_purr;
>> +
>> + idle_loop_prolog(&in_purr);
>> + local_irq_enable();
>
> snooze_loop has already registered in cpuidle framework to handle snooze state.
> where disable the irq? Why do "enable" here?
>
>> +/*
>> + * States for dedicated partition case.
>> + */
>> +static struct cpuidle_state dedicated_states[MAX_IDLE_STATE_COUNT] = {
>> + { /* Snooze */
>> + .name = "snooze",
>> + .desc = "snooze",
>> + .flags = CPUIDLE_FLAG_TIME_VALID,
>> + .exit_latency = 0,
>> + .target_residency = 0,
>> + .enter = &snooze_loop },
>> + { /* CEDE */
>> + .name = "CEDE",
>> + .desc = "CEDE",
>> + .flags = CPUIDLE_FLAG_TIME_VALID,
>> + .exit_latency = 10,
>> + .target_residency = 100,
>> + .enter = &dedicated_cede_loop },
>> +};
>> +
>> +/*
>> + * States for shared partition case.
>> + */
>> +static struct cpuidle_state shared_states[MAX_IDLE_STATE_COUNT] = {
>> + { /* Shared Cede */
>> + .name = "Shared Cede",
>> + .desc = "Shared Cede",
>> + .flags = CPUIDLE_FLAG_TIME_VALID,
>> + .exit_latency = 0,
>> + .target_residency = 0,
>> + .enter = &shared_cede_loop },
>> +};
>> +
>> +static void __exit power_processor_idle_exit(void)
>> +{
>> +
>> + unregister_cpu_notifier(&setup_hotplug_notifier);
>
> Remove a blank line.
>
>> + cpuidle_unregister(&power_idle_driver);
>> + return;
>> +}
>> +
>> +module_init(power_processor_idle_init);
>> +module_exit(power_processor_idle_exit);
>> +
>
> Did you have tested the module? If not tested, please don't use the module.
>
>> +MODULE_AUTHOR("Deepthi Dharwar <deepthi@xxxxxxxxxxxxxxxxxx>");
>> +MODULE_DESCRIPTION("Cpuidle driver for IBM POWER platforms");
>> +MODULE_LICENSE("GPL");
>>
>
