[linux.git] / drivers / cpuidle / cpuidle-powernv.c

/*
 *  cpuidle-powernv - idle state cpuidle driver.
 *  Adapted from drivers/cpuidle/cpuidle-pseries
 *
 */

#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 <linux/clockchips.h>
#include <linux/of.h>
#include <linux/slab.h>

#include <asm/machdep.h>
#include <asm/firmware.h>
#include <asm/opal.h>
#include <asm/runlatch.h>
#include <asm/cpuidle.h>

/*
 * Expose only those Hardware idle states via the cpuidle framework
 * that have latency value below POWERNV_THRESHOLD_LATENCY_NS.
 */
#define POWERNV_THRESHOLD_LATENCY_NS 200000

static struct cpuidle_driver powernv_idle_driver = {
	.name             = "powernv_idle",
	.owner            = THIS_MODULE,
};

static int max_idle_state;
static struct cpuidle_state *cpuidle_state_table;

struct stop_psscr_table {
	u64 val;
	u64 mask;
};

static struct stop_psscr_table stop_psscr_table[CPUIDLE_STATE_MAX];

static u64 snooze_timeout;
static bool snooze_timeout_en;

static int snooze_loop(struct cpuidle_device *dev,
			struct cpuidle_driver *drv,
			int index)
{
	u64 snooze_exit_time;

	local_irq_enable();
	set_thread_flag(TIF_POLLING_NRFLAG);

	snooze_exit_time = get_tb() + snooze_timeout;
	ppc64_runlatch_off();
	while (!need_resched()) {
		HMT_very_low();
		if (snooze_timeout_en && get_tb() > snooze_exit_time)
			break;
	}

	HMT_medium();
	ppc64_runlatch_on();
	clear_thread_flag(TIF_POLLING_NRFLAG);
	smp_mb();
	return index;
}

static int nap_loop(struct cpuidle_device *dev,
			struct cpuidle_driver *drv,
			int index)
{
	ppc64_runlatch_off();
	power7_idle();
	ppc64_runlatch_on();
	return index;
}

/* Register for fastsleep only in oneshot mode of broadcast */
#ifdef CONFIG_TICK_ONESHOT
static int fastsleep_loop(struct cpuidle_device *dev,
				struct cpuidle_driver *drv,
				int index)
{
	unsigned long old_lpcr = mfspr(SPRN_LPCR);
	unsigned long new_lpcr;

	if (unlikely(system_state < SYSTEM_RUNNING))
		return index;

	new_lpcr = old_lpcr;
	/* Do not exit powersave upon decrementer as we've setup the timer
	 * offload.
	 */
	new_lpcr &= ~LPCR_PECE1;

	mtspr(SPRN_LPCR, new_lpcr);
	power7_sleep();

	mtspr(SPRN_LPCR, old_lpcr);

	return index;
}
#endif

static int stop_loop(struct cpuidle_device *dev,
		     struct cpuidle_driver *drv,
		     int index)
{
	ppc64_runlatch_off();
	power9_idle_stop(stop_psscr_table[index].val,
			 stop_psscr_table[index].mask);
	ppc64_runlatch_on();
	return index;
}

/*
 * States for dedicated partition case.
 */
static struct cpuidle_state powernv_states[CPUIDLE_STATE_MAX] = {
	{ /* Snooze */
		.name = "snooze",
		.desc = "snooze",
		.exit_latency = 0,
		.target_residency = 0,
		.enter = snooze_loop },
};

static int powernv_cpuidle_cpu_online(unsigned int cpu)
{
	struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);

	if (dev && cpuidle_get_driver()) {
		cpuidle_pause_and_lock();
		cpuidle_enable_device(dev);
		cpuidle_resume_and_unlock();
	}
	return 0;
}

static int powernv_cpuidle_cpu_dead(unsigned int cpu)
{
	struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);

	if (dev && cpuidle_get_driver()) {
		cpuidle_pause_and_lock();
		cpuidle_disable_device(dev);
		cpuidle_resume_and_unlock();
	}
	return 0;
}

/*
 * powernv_cpuidle_driver_init()
 */
static int powernv_cpuidle_driver_init(void)
{
	int idle_state;
	struct cpuidle_driver *drv = &powernv_idle_driver;

	drv->state_count = 0;

	for (idle_state = 0; idle_state < max_idle_state; ++idle_state) {
		/* Is the state not enabled? */
		if (cpuidle_state_table[idle_state].enter == NULL)
			continue;

		drv->states[drv->state_count] =	/* structure copy */
			cpuidle_state_table[idle_state];

		drv->state_count += 1;
	}

	return 0;
}

static inline void add_powernv_state(int index, const char *name,
				     unsigned int flags,
				     int (*idle_fn)(struct cpuidle_device *,
						    struct cpuidle_driver *,
						    int),
				     unsigned int target_residency,
				     unsigned int exit_latency,
				     u64 psscr_val, u64 psscr_mask)
{
	strlcpy(powernv_states[index].name, name, CPUIDLE_NAME_LEN);
	strlcpy(powernv_states[index].desc, name, CPUIDLE_NAME_LEN);
	powernv_states[index].flags = flags;
	powernv_states[index].target_residency = target_residency;
	powernv_states[index].exit_latency = exit_latency;
	powernv_states[index].enter = idle_fn;
	stop_psscr_table[index].val = psscr_val;
	stop_psscr_table[index].mask = psscr_mask;
}

/*
 * Returns 0 if prop1_len == prop2_len. Else returns -1
 */
static inline int validate_dt_prop_sizes(const char *prop1, int prop1_len,
					 const char *prop2, int prop2_len)
{
	if (prop1_len == prop2_len)
		return 0;

	pr_warn("cpuidle-powernv: array sizes don't match for %s and %s\n",
		prop1, prop2);
	return -1;
}

static int powernv_add_idle_states(void)
{
	struct device_node *power_mgt;
	int nr_idle_states = 1; /* Snooze */
	int dt_idle_states, count;
	u32 latency_ns[CPUIDLE_STATE_MAX];
	u32 residency_ns[CPUIDLE_STATE_MAX];
	u32 flags[CPUIDLE_STATE_MAX];
	u64 psscr_val[CPUIDLE_STATE_MAX];
	u64 psscr_mask[CPUIDLE_STATE_MAX];
	const char *names[CPUIDLE_STATE_MAX];
	u32 has_stop_states = 0;
	int i, rc;

	/* Currently we have snooze statically defined */

	power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
	if (!power_mgt) {
		pr_warn("opal: PowerMgmt Node not found\n");
		goto out;
	}

	/* Read values of any property to determine the num of idle states */
	dt_idle_states = of_property_count_u32_elems(power_mgt, "ibm,cpu-idle-state-flags");
	if (dt_idle_states < 0) {
		pr_warn("cpuidle-powernv: no idle states found in the DT\n");
		goto out;
	}

	count = of_property_count_u32_elems(power_mgt,
					    "ibm,cpu-idle-state-latencies-ns");

	if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags", dt_idle_states,
				   "ibm,cpu-idle-state-latencies-ns",
				   count) != 0)
		goto out;

	count = of_property_count_strings(power_mgt,
					  "ibm,cpu-idle-state-names");
	if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags", dt_idle_states,
				   "ibm,cpu-idle-state-names",
				   count) != 0)
		goto out;

	/*
	 * Since snooze is used as first idle state, max idle states allowed is
	 * CPUIDLE_STATE_MAX -1
	 */
	if (dt_idle_states > CPUIDLE_STATE_MAX - 1) {
		pr_warn("cpuidle-powernv: discovered idle states more than allowed");
		dt_idle_states = CPUIDLE_STATE_MAX - 1;
	}

	if (of_property_read_u32_array(power_mgt,
			"ibm,cpu-idle-state-flags", flags, dt_idle_states)) {
		pr_warn("cpuidle-powernv : missing ibm,cpu-idle-state-flags in DT\n");
		goto out;
	}

	if (of_property_read_u32_array(power_mgt,
		"ibm,cpu-idle-state-latencies-ns", latency_ns,
		dt_idle_states)) {
		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
		goto out;
	}
	if (of_property_read_string_array(power_mgt,
		"ibm,cpu-idle-state-names", names, dt_idle_states) < 0) {
		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-names in DT\n");
		goto out;
	}

	/*
	 * If the idle states use stop instruction, probe for psscr values
	 * and psscr mask which are necessary to specify required stop level.
	 */
	has_stop_states = (flags[0] &
			   (OPAL_PM_STOP_INST_FAST | OPAL_PM_STOP_INST_DEEP));
	if (has_stop_states) {
		count = of_property_count_u64_elems(power_mgt,
						    "ibm,cpu-idle-state-psscr");
		if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
					   dt_idle_states,
					   "ibm,cpu-idle-state-psscr",
					   count) != 0)
			goto out;

		count = of_property_count_u64_elems(power_mgt,
						    "ibm,cpu-idle-state-psscr-mask");
		if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
					   dt_idle_states,
					   "ibm,cpu-idle-state-psscr-mask",
					   count) != 0)
			goto out;

		if (of_property_read_u64_array(power_mgt,
		    "ibm,cpu-idle-state-psscr", psscr_val, dt_idle_states)) {
			pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr in DT\n");
			goto out;
		}

		if (of_property_read_u64_array(power_mgt,
					       "ibm,cpu-idle-state-psscr-mask",
						psscr_mask, dt_idle_states)) {
			pr_warn("cpuidle-powernv:Missing ibm,cpu-idle-state-psscr-mask in DT\n");
			goto out;
		}
	}

	count = of_property_count_u32_elems(power_mgt,
					    "ibm,cpu-idle-state-residency-ns");

	if (count < 0) {
		rc = count;
	} else if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
					  dt_idle_states,
					  "ibm,cpu-idle-state-residency-ns",
					  count) != 0) {
		goto out;
	} else {
		rc = of_property_read_u32_array(power_mgt,
						"ibm,cpu-idle-state-residency-ns",
						residency_ns, dt_idle_states);
	}

	for (i = 0; i < dt_idle_states; i++) {
		unsigned int exit_latency, target_residency;
		/*
		 * If an idle state has exit latency beyond
		 * POWERNV_THRESHOLD_LATENCY_NS then don't use it
		 * in cpu-idle.
		 */
		if (latency_ns[i] > POWERNV_THRESHOLD_LATENCY_NS)
			continue;
		/*
		 * Firmware passes residency and latency values in ns.
		 * cpuidle expects it in us.
		 */
		exit_latency = latency_ns[i] / 1000;
		if (!rc)
			target_residency = residency_ns[i] / 1000;
		else
			target_residency = 0;

		if (has_stop_states) {
			int err = validate_psscr_val_mask(&psscr_val[i],
							  &psscr_mask[i],
							  flags[i]);
			if (err) {
				report_invalid_psscr_val(psscr_val[i], err);
				continue;
			}
		}

		/*
		 * For nap and fastsleep, use default target_residency
		 * values if f/w does not expose it.
		 */
		if (flags[i] & OPAL_PM_NAP_ENABLED) {
			if (!rc)
				target_residency = 100;
			/* Add NAP state */
			add_powernv_state(nr_idle_states, "Nap",
					  CPUIDLE_FLAG_NONE, nap_loop,
					  target_residency, exit_latency, 0, 0);
		} else if ((flags[i] & OPAL_PM_STOP_INST_FAST) &&
				!(flags[i] & OPAL_PM_TIMEBASE_STOP)) {
			add_powernv_state(nr_idle_states, names[i],
					  CPUIDLE_FLAG_NONE, stop_loop,
					  target_residency, exit_latency,
					  psscr_val[i], psscr_mask[i]);
		}

		/*
		 * All cpuidle states with CPUIDLE_FLAG_TIMER_STOP set must come
		 * within this config dependency check.
		 */
#ifdef CONFIG_TICK_ONESHOT
		if (flags[i] & OPAL_PM_SLEEP_ENABLED ||
			flags[i] & OPAL_PM_SLEEP_ENABLED_ER1) {
			if (!rc)
				target_residency = 300000;
			/* Add FASTSLEEP state */
			add_powernv_state(nr_idle_states, "FastSleep",
					  CPUIDLE_FLAG_TIMER_STOP,
					  fastsleep_loop,
					  target_residency, exit_latency, 0, 0);
		} else if ((flags[i] & OPAL_PM_STOP_INST_DEEP) &&
				(flags[i] & OPAL_PM_TIMEBASE_STOP)) {
			add_powernv_state(nr_idle_states, names[i],
					  CPUIDLE_FLAG_TIMER_STOP, stop_loop,
					  target_residency, exit_latency,
					  psscr_val[i], psscr_mask[i]);
		}
#endif
		nr_idle_states++;
	}
out:
	return nr_idle_states;
}

/*
 * powernv_idle_probe()
 * Choose state table for shared versus dedicated partition
 */
static int powernv_idle_probe(void)
{
	if (cpuidle_disable != IDLE_NO_OVERRIDE)
		return -ENODEV;

	if (firmware_has_feature(FW_FEATURE_OPAL)) {
		cpuidle_state_table = powernv_states;
		/* Device tree can indicate more idle states */
		max_idle_state = powernv_add_idle_states();
		if (max_idle_state > 1) {
			snooze_timeout_en = true;
			snooze_timeout = powernv_states[1].target_residency *
					 tb_ticks_per_usec;
		}
 	} else
 		return -ENODEV;

	return 0;
}

static int __init powernv_processor_idle_init(void)
{
	int retval;

	retval = powernv_idle_probe();
	if (retval)
		return retval;

	powernv_cpuidle_driver_init();
	retval = cpuidle_register(&powernv_idle_driver, NULL);
	if (retval) {
		printk(KERN_DEBUG "Registration of powernv driver failed.\n");
		return retval;
	}

	retval = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
					   "cpuidle/powernv:online",
					   powernv_cpuidle_cpu_online, NULL);
	WARN_ON(retval < 0);
	retval = cpuhp_setup_state_nocalls(CPUHP_CPUIDLE_DEAD,
					   "cpuidle/powernv:dead", NULL,
					   powernv_cpuidle_cpu_dead);
	WARN_ON(retval < 0);
	printk(KERN_DEBUG "powernv_idle_driver registered\n");
	return 0;
}

device_initcall(powernv_processor_idle_init);
Commit	Line	Data
2c2e6ecf DD	1	/*
	2	* cpuidle-powernv - idle state cpuidle driver.
	3	* Adapted from drivers/cpuidle/cpuidle-pseries
	4	*
	5	*/
	6
	7	#include <linux/kernel.h>
	8	#include <linux/module.h>
	9	#include <linux/init.h>
	10	#include <linux/moduleparam.h>
	11	#include <linux/cpuidle.h>
	12	#include <linux/cpu.h>
	13	#include <linux/notifier.h>
0d948730	14	#include <linux/clockchips.h>
0888839c	15	#include <linux/of.h>
92c83ff5	16	#include <linux/slab.h>
2c2e6ecf DD	17
	18	#include <asm/machdep.h>
	19	#include <asm/firmware.h>
8eb8ac89	20	#include <asm/opal.h>
591ac0cb	21	#include <asm/runlatch.h>
09206b60	22	#include <asm/cpuidle.h>
2c2e6ecf	23
9e9fc6f0 GS	24	/*
	25	* Expose only those Hardware idle states via the cpuidle framework
	26	* that have latency value below POWERNV_THRESHOLD_LATENCY_NS.
	27	*/
3005c597 SP	28	#define POWERNV_THRESHOLD_LATENCY_NS 200000
3005c597 SP	29
ed61390b	30	static struct cpuidle_driver powernv_idle_driver = {
2c2e6ecf DD	31	.name = "powernv_idle",
	32	.owner = THIS_MODULE,
	33	};
	34
	35	static int max_idle_state;
	36	static struct cpuidle_state *cpuidle_state_table;
3005c597	37
09206b60 GS	38	struct stop_psscr_table {
	39	u64 val;
	40	u64 mask;
	41	};
	42
	43	static struct stop_psscr_table stop_psscr_table[CPUIDLE_STATE_MAX];
3005c597	44
78eaa10f SB	45	static u64 snooze_timeout;
78eaa10f SB	46	static bool snooze_timeout_en;
2c2e6ecf DD	47
	48	static int snooze_loop(struct cpuidle_device *dev,
	49	struct cpuidle_driver *drv,
	50	int index)
	51	{
78eaa10f SB	52	u64 snooze_exit_time;
78eaa10f SB	53
2c2e6ecf DD	54	local_irq_enable();
	55	set_thread_flag(TIF_POLLING_NRFLAG);
	56
78eaa10f	57	snooze_exit_time = get_tb() + snooze_timeout;
591ac0cb	58	ppc64_runlatch_off();
2c2e6ecf	59	while (!need_resched()) {
2c2e6ecf	60	HMT_very_low();
78eaa10f SB	61	if (snooze_timeout_en && get_tb() > snooze_exit_time)
78eaa10f SB	62	break;
2c2e6ecf DD	63	}
	64
	65	HMT_medium();
591ac0cb	66	ppc64_runlatch_on();
2c2e6ecf DD	67	clear_thread_flag(TIF_POLLING_NRFLAG);
	68	smp_mb();
	69	return index;
	70	}
	71
	72	static int nap_loop(struct cpuidle_device *dev,
	73	struct cpuidle_driver *drv,
	74	int index)
	75	{
591ac0cb	76	ppc64_runlatch_off();
2c2e6ecf	77	power7_idle();
591ac0cb	78	ppc64_runlatch_on();
2c2e6ecf DD	79	return index;
	80	}
	81
cc5a2f7b	82	/* Register for fastsleep only in oneshot mode of broadcast */
cc5a2f7b	83	#ifdef CONFIG_TICK_ONESHOT
0d948730 PM	84	static int fastsleep_loop(struct cpuidle_device *dev,
	85	struct cpuidle_driver *drv,
	86	int index)
	87	{
	88	unsigned long old_lpcr = mfspr(SPRN_LPCR);
	89	unsigned long new_lpcr;
	90
	91	if (unlikely(system_state < SYSTEM_RUNNING))
	92	return index;
	93
	94	new_lpcr = old_lpcr;
9b6a68d9 MN	95	/* Do not exit powersave upon decrementer as we've setup the timer
9b6a68d9 MN	96	* offload.
0d948730	97	*/
9b6a68d9	98	new_lpcr &= ~LPCR_PECE1;
0d948730 PM	99
	100	mtspr(SPRN_LPCR, new_lpcr);
	101	power7_sleep();
	102
	103	mtspr(SPRN_LPCR, old_lpcr);
	104
	105	return index;
	106	}
cc5a2f7b	107	#endif
3005c597 SP	108
	109	static int stop_loop(struct cpuidle_device *dev,
	110	struct cpuidle_driver *drv,
	111	int index)
	112	{
	113	ppc64_runlatch_off();
09206b60 GS	114	power9_idle_stop(stop_psscr_table[index].val,
09206b60 GS	115	stop_psscr_table[index].mask);
3005c597 SP	116	ppc64_runlatch_on();
	117	return index;
	118	}
	119
2c2e6ecf DD	120	/*
	121	* States for dedicated partition case.
	122	*/
169f3fae	123	static struct cpuidle_state powernv_states[CPUIDLE_STATE_MAX] = {
2c2e6ecf DD	124	{ /* Snooze */
	125	.name = "snooze",
	126	.desc = "snooze",
2c2e6ecf DD	127	.exit_latency = 0,
2c2e6ecf DD	128	.target_residency = 0,
957efced	129	.enter = snooze_loop },
2c2e6ecf DD	130	};
2c2e6ecf DD	131
10fcca9d	132	static int powernv_cpuidle_cpu_online(unsigned int cpu)
2c2e6ecf	133	{
10fcca9d	134	struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
2c2e6ecf DD	135
2c2e6ecf DD	136	if (dev && cpuidle_get_driver()) {
10fcca9d SAS	137	cpuidle_pause_and_lock();
	138	cpuidle_enable_device(dev);
	139	cpuidle_resume_and_unlock();
	140	}
	141	return 0;
	142	}
2c2e6ecf	143
10fcca9d SAS	144	static int powernv_cpuidle_cpu_dead(unsigned int cpu)
	145	{
	146	struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
2c2e6ecf	147
10fcca9d SAS	148	if (dev && cpuidle_get_driver()) {
	149	cpuidle_pause_and_lock();
	150	cpuidle_disable_device(dev);
	151	cpuidle_resume_and_unlock();
2c2e6ecf	152	}
10fcca9d	153	return 0;
2c2e6ecf DD	154	}
2c2e6ecf DD	155
2c2e6ecf DD	156	/*
	157	* powernv_cpuidle_driver_init()
	158	*/
	159	static int powernv_cpuidle_driver_init(void)
	160	{
	161	int idle_state;
	162	struct cpuidle_driver *drv = &powernv_idle_driver;
	163
	164	drv->state_count = 0;
	165
	166	for (idle_state = 0; idle_state < max_idle_state; ++idle_state) {
	167	/* Is the state not enabled? */
	168	if (cpuidle_state_table[idle_state].enter == NULL)
	169	continue;
	170
	171	drv->states[drv->state_count] = /* structure copy */
	172	cpuidle_state_table[idle_state];
	173
	174	drv->state_count += 1;
	175	}
	176
	177	return 0;
	178	}
	179
9e9fc6f0 GS	180	static inline void add_powernv_state(int index, const char *name,
	181	unsigned int flags,
	182	int (idle_fn)(struct cpuidle_device ,
	183	struct cpuidle_driver *,
	184	int),
	185	unsigned int target_residency,
	186	unsigned int exit_latency,
09206b60	187	u64 psscr_val, u64 psscr_mask)
9e9fc6f0 GS	188	{
	189	strlcpy(powernv_states[index].name, name, CPUIDLE_NAME_LEN);
	190	strlcpy(powernv_states[index].desc, name, CPUIDLE_NAME_LEN);
	191	powernv_states[index].flags = flags;
	192	powernv_states[index].target_residency = target_residency;
	193	powernv_states[index].exit_latency = exit_latency;
	194	powernv_states[index].enter = idle_fn;
09206b60 GS	195	stop_psscr_table[index].val = psscr_val;
09206b60 GS	196	stop_psscr_table[index].mask = psscr_mask;
9e9fc6f0 GS	197	}
9e9fc6f0 GS	198
ecad4502 GS	199	/*
	200	* Returns 0 if prop1_len == prop2_len. Else returns -1
	201	*/
	202	static inline int validate_dt_prop_sizes(const char *prop1, int prop1_len,
	203	const char *prop2, int prop2_len)
	204	{
	205	if (prop1_len == prop2_len)
	206	return 0;
	207
	208	pr_warn("cpuidle-powernv: array sizes don't match for %s and %s\n",
	209	prop1, prop2);
	210	return -1;
	211	}
	212
0888839c PM	213	static int powernv_add_idle_states(void)
	214	{
	215	struct device_node *power_mgt;
0888839c	216	int nr_idle_states = 1; /* Snooze */
ecad4502	217	int dt_idle_states, count;
957efced SP	218	u32 latency_ns[CPUIDLE_STATE_MAX];
	219	u32 residency_ns[CPUIDLE_STATE_MAX];
	220	u32 flags[CPUIDLE_STATE_MAX];
3005c597	221	u64 psscr_val[CPUIDLE_STATE_MAX];
09206b60	222	u64 psscr_mask[CPUIDLE_STATE_MAX];
3005c597	223	const char *names[CPUIDLE_STATE_MAX];
09206b60	224	u32 has_stop_states = 0;
92c83ff5	225	int i, rc;
0888839c PM	226
	227	/* Currently we have snooze statically defined */
	228
	229	power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
	230	if (!power_mgt) {
	231	pr_warn("opal: PowerMgmt Node not found\n");
92c83ff5	232	goto out;
0888839c PM	233	}
0888839c PM	234
70734a78 PM	235	/* Read values of any property to determine the num of idle states */
	236	dt_idle_states = of_property_count_u32_elems(power_mgt, "ibm,cpu-idle-state-flags");
	237	if (dt_idle_states < 0) {
	238	pr_warn("cpuidle-powernv: no idle states found in the DT\n");
92c83ff5	239	goto out;
0888839c PM	240	}
0888839c PM	241
ecad4502 GS	242	count = of_property_count_u32_elems(power_mgt,
	243	"ibm,cpu-idle-state-latencies-ns");
	244
	245	if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags", dt_idle_states,
	246	"ibm,cpu-idle-state-latencies-ns",
	247	count) != 0)
	248	goto out;
	249
	250	count = of_property_count_strings(power_mgt,
	251	"ibm,cpu-idle-state-names");
	252	if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags", dt_idle_states,
	253	"ibm,cpu-idle-state-names",
	254	count) != 0)
	255	goto out;
	256
957efced SP	257	/*
	258	* Since snooze is used as first idle state, max idle states allowed is
	259	* CPUIDLE_STATE_MAX -1
	260	*/
	261	if (dt_idle_states > CPUIDLE_STATE_MAX - 1) {
	262	pr_warn("cpuidle-powernv: discovered idle states more than allowed");
	263	dt_idle_states = CPUIDLE_STATE_MAX - 1;
	264	}
	265
70734a78 PM	266	if (of_property_read_u32_array(power_mgt,
	267	"ibm,cpu-idle-state-flags", flags, dt_idle_states)) {
	268	pr_warn("cpuidle-powernv : missing ibm,cpu-idle-state-flags in DT\n");
957efced	269	goto out;
70734a78	270	}
92c83ff5	271
957efced SP	272	if (of_property_read_u32_array(power_mgt,
	273	"ibm,cpu-idle-state-latencies-ns", latency_ns,
	274	dt_idle_states)) {
92c83ff5	275	pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
957efced	276	goto out;
74aa51b5	277	}
3005c597 SP	278	if (of_property_read_string_array(power_mgt,
	279	"ibm,cpu-idle-state-names", names, dt_idle_states) < 0) {
	280	pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-names in DT\n");
	281	goto out;
	282	}
	283
	284	/*
	285	* If the idle states use stop instruction, probe for psscr values
09206b60	286	* and psscr mask which are necessary to specify required stop level.
3005c597	287	*/
09206b60 GS	288	has_stop_states = (flags[0] &
	289	(OPAL_PM_STOP_INST_FAST \| OPAL_PM_STOP_INST_DEEP));
	290	if (has_stop_states) {
ecad4502 GS	291	count = of_property_count_u64_elems(power_mgt,
	292	"ibm,cpu-idle-state-psscr");
	293	if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
	294	dt_idle_states,
	295	"ibm,cpu-idle-state-psscr",
	296	count) != 0)
	297	goto out;
	298
	299	count = of_property_count_u64_elems(power_mgt,
	300	"ibm,cpu-idle-state-psscr-mask");
	301	if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
	302	dt_idle_states,
	303	"ibm,cpu-idle-state-psscr-mask",
	304	count) != 0)
	305	goto out;
	306
3005c597 SP	307	if (of_property_read_u64_array(power_mgt,
3005c597 SP	308	"ibm,cpu-idle-state-psscr", psscr_val, dt_idle_states)) {
09206b60	309	pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr in DT\n");
3005c597 SP	310	goto out;
3005c597 SP	311	}
74aa51b5	312
09206b60 GS	313	if (of_property_read_u64_array(power_mgt,
	314	"ibm,cpu-idle-state-psscr-mask",
	315	psscr_mask, dt_idle_states)) {
	316	pr_warn("cpuidle-powernv:Missing ibm,cpu-idle-state-psscr-mask in DT\n");
	317	goto out;
	318	}
	319	}
	320
ecad4502 GS	321	count = of_property_count_u32_elems(power_mgt,
	322	"ibm,cpu-idle-state-residency-ns");
	323
	324	if (count < 0) {
	325	rc = count;
	326	} else if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
	327	dt_idle_states,
	328	"ibm,cpu-idle-state-residency-ns",
	329	count) != 0) {
	330	goto out;
	331	} else {
	332	rc = of_property_read_u32_array(power_mgt,
	333	"ibm,cpu-idle-state-residency-ns",
	334	residency_ns, dt_idle_states);
	335	}
0888839c PM	336
0888839c PM	337	for (i = 0; i < dt_idle_states; i++) {
9e9fc6f0	338	unsigned int exit_latency, target_residency;
3005c597 SP	339	/*
	340	* If an idle state has exit latency beyond
	341	* POWERNV_THRESHOLD_LATENCY_NS then don't use it
	342	* in cpu-idle.
	343	*/
	344	if (latency_ns[i] > POWERNV_THRESHOLD_LATENCY_NS)
	345	continue;
9e9fc6f0 GS	346	/*
	347	* Firmware passes residency and latency values in ns.
	348	* cpuidle expects it in us.
	349	*/
	350	exit_latency = latency_ns[i] / 1000;
	351	if (!rc)
	352	target_residency = residency_ns[i] / 1000;
	353	else
	354	target_residency = 0;
0888839c	355
09206b60 GS	356	if (has_stop_states) {
	357	int err = validate_psscr_val_mask(&psscr_val[i],
	358	&psscr_mask[i],
	359	flags[i]);
	360	if (err) {
	361	report_invalid_psscr_val(psscr_val[i], err);
	362	continue;
	363	}
	364	}
	365
92c83ff5	366	/*
9e9fc6f0 GS	367	* For nap and fastsleep, use default target_residency
9e9fc6f0 GS	368	* values if f/w does not expose it.
74aa51b5	369	*/
70734a78	370	if (flags[i] & OPAL_PM_NAP_ENABLED) {
9e9fc6f0 GS	371	if (!rc)
9e9fc6f0 GS	372	target_residency = 100;
0888839c	373	/* Add NAP state */
9e9fc6f0 GS	374	add_powernv_state(nr_idle_states, "Nap",
9e9fc6f0 GS	375	CPUIDLE_FLAG_NONE, nap_loop,
09206b60	376	target_residency, exit_latency, 0, 0);
3005c597 SP	377	} else if ((flags[i] & OPAL_PM_STOP_INST_FAST) &&
3005c597 SP	378	!(flags[i] & OPAL_PM_TIMEBASE_STOP)) {
9e9fc6f0 GS	379	add_powernv_state(nr_idle_states, names[i],
	380	CPUIDLE_FLAG_NONE, stop_loop,
	381	target_residency, exit_latency,
09206b60	382	psscr_val[i], psscr_mask[i]);
cc5a2f7b	383	}
	384
	385	/*
	386	* All cpuidle states with CPUIDLE_FLAG_TIMER_STOP set must come
	387	* within this config dependency check.
	388	*/
	389	#ifdef CONFIG_TICK_ONESHOT
	390	if (flags[i] & OPAL_PM_SLEEP_ENABLED \|\|
70734a78	391	flags[i] & OPAL_PM_SLEEP_ENABLED_ER1) {
9e9fc6f0 GS	392	if (!rc)
9e9fc6f0 GS	393	target_residency = 300000;
0888839c	394	/* Add FASTSLEEP state */
9e9fc6f0 GS	395	add_powernv_state(nr_idle_states, "FastSleep",
	396	CPUIDLE_FLAG_TIMER_STOP,
	397	fastsleep_loop,
09206b60	398	target_residency, exit_latency, 0, 0);
3005c597 SP	399	} else if ((flags[i] & OPAL_PM_STOP_INST_DEEP) &&
3005c597 SP	400	(flags[i] & OPAL_PM_TIMEBASE_STOP)) {
9e9fc6f0 GS	401	add_powernv_state(nr_idle_states, names[i],
	402	CPUIDLE_FLAG_TIMER_STOP, stop_loop,
	403	target_residency, exit_latency,
09206b60	404	psscr_val[i], psscr_mask[i]);
0888839c	405	}
cc5a2f7b	406	#endif
92c83ff5	407	nr_idle_states++;
0888839c	408	}
92c83ff5	409	out:
0888839c PM	410	return nr_idle_states;
	411	}
	412
2c2e6ecf DD	413	/*
	414	* powernv_idle_probe()
	415	* Choose state table for shared versus dedicated partition
	416	*/
	417	static int powernv_idle_probe(void)
	418	{
2c2e6ecf DD	419	if (cpuidle_disable != IDLE_NO_OVERRIDE)
	420	return -ENODEV;
	421
e4d54f71	422	if (firmware_has_feature(FW_FEATURE_OPAL)) {
2c2e6ecf	423	cpuidle_state_table = powernv_states;
0888839c PM	424	/* Device tree can indicate more idle states */
0888839c PM	425	max_idle_state = powernv_add_idle_states();
78eaa10f SB	426	if (max_idle_state > 1) {
	427	snooze_timeout_en = true;
	428	snooze_timeout = powernv_states[1].target_residency *
	429	tb_ticks_per_usec;
	430	}
2c2e6ecf DD	431	} else
	432	return -ENODEV;
	433
	434	return 0;
	435	}
	436
	437	static int __init powernv_processor_idle_init(void)
	438	{
	439	int retval;
	440
	441	retval = powernv_idle_probe();
	442	if (retval)
	443	return retval;
	444
	445	powernv_cpuidle_driver_init();
	446	retval = cpuidle_register(&powernv_idle_driver, NULL);
	447	if (retval) {
	448	printk(KERN_DEBUG "Registration of powernv driver failed.\n");
	449	return retval;
	450	}
	451
10fcca9d SAS	452	retval = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
	453	"cpuidle/powernv:online",
	454	powernv_cpuidle_cpu_online, NULL);
	455	WARN_ON(retval < 0);
	456	retval = cpuhp_setup_state_nocalls(CPUHP_CPUIDLE_DEAD,
	457	"cpuidle/powernv:dead", NULL,
	458	powernv_cpuidle_cpu_dead);
	459	WARN_ON(retval < 0);
2c2e6ecf DD	460	printk(KERN_DEBUG "powernv_idle_driver registered\n");
	461	return 0;
	462	}
	463
	464	device_initcall(powernv_processor_idle_init);