[PATCH v2 2/2] powernv/cpuidle: Use parsed device tree values for cpuidle_init

From: Akshay Adiga
Date: Mon Jul 02 2018 - 10:24:22 EST


Export pnv_idle_states and nr_pnv_idle_states so that its accessible to
cpuidle driver. Use properties from pnv_idle_states structure for powernv
cpuidle_init.

Signed-off-by: Akshay Adiga <akshay.adiga@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/include/asm/cpuidle.h | 2 +
drivers/cpuidle/cpuidle-powernv.c | 143 +++++------------------------
2 files changed, 26 insertions(+), 119 deletions(-)

diff --git a/arch/powerpc/include/asm/cpuidle.h b/arch/powerpc/include/asm/cpuidle.h
index 574b0ce1d671..43e5f31fe64d 100644
--- a/arch/powerpc/include/asm/cpuidle.h
+++ b/arch/powerpc/include/asm/cpuidle.h
@@ -90,6 +90,8 @@ struct pnv_idle_states_t {
bool valid;
};

+extern struct pnv_idle_states_t *pnv_idle_states;
+extern int nr_pnv_idle_states;
extern u32 pnv_fastsleep_workaround_at_entry[];
extern u32 pnv_fastsleep_workaround_at_exit[];

diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c
index 7ab613d4dca1..ec93b2ae7b17 100644
--- a/drivers/cpuidle/cpuidle-powernv.c
+++ b/drivers/cpuidle/cpuidle-powernv.c
@@ -242,6 +242,7 @@ static inline void add_powernv_state(int index, const char *name,
powernv_states[index].target_residency = target_residency;
powernv_states[index].exit_latency = exit_latency;
powernv_states[index].enter = idle_fn;
+ /* For power8 and below psscr_* will be 0 */
stop_psscr_table[index].val = psscr_val;
stop_psscr_table[index].mask = psscr_mask;
}
@@ -263,179 +264,84 @@ static inline int validate_dt_prop_sizes(const char *prop1, int prop1_len,
extern u32 pnv_get_supported_cpuidle_states(void);
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];
+ int dt_idle_states;
u32 has_stop_states = 0;
- int i, rc;
+ int i;
u32 supported_flags = pnv_get_supported_cpuidle_states();


/* 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");
+ if (nr_pnv_idle_states <= 0) {
+ pr_warn("cpuidle-powernv : Only Snooze is available\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;
+ /* TODO: Count only states which are eligible for cpuidle */
+ dt_idle_states = nr_pnv_idle_states;

/*
* 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) {
+ if (nr_pnv_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] &
+ has_stop_states = (pnv_idle_states[0].flags &
(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;
bool stops_timebase = false;
+ struct pnv_idle_states_t *state = &pnv_idle_states[i];

/*
* Skip the platform idle state whose flag isn't in
* the supported_cpuidle_states flag mask.
*/
- if ((flags[i] & supported_flags) != flags[i])
+ if ((state->flags & supported_flags) != state->flags)
continue;
/*
* 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)
+ if (state->latency_ns > POWERNV_THRESHOLD_LATENCY_NS)
continue;
/*
* Firmware passes residency and latency values in ns.
* cpuidle expects it in us.
*/
- exit_latency = DIV_ROUND_UP(latency_ns[i], 1000);
- if (!rc)
- target_residency = DIV_ROUND_UP(residency_ns[i], 1000);
- else
- target_residency = 0;
+ exit_latency = DIV_ROUND_UP(state->latency_ns, 1000);
+ target_residency = DIV_ROUND_UP(state->residency_ns, 1000);

if (has_stop_states && !(state->valid))
continue;

- if (flags[i] & OPAL_PM_TIMEBASE_STOP)
+ if (state->flags & OPAL_PM_TIMEBASE_STOP)
stops_timebase = true;

/*
* 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;
+ if (state->flags & OPAL_PM_NAP_ENABLED) {
/* Add NAP state */
add_powernv_state(nr_idle_states, "Nap",
CPUIDLE_FLAG_NONE, nap_loop,
target_residency, exit_latency, 0, 0);
} else if (has_stop_states && !stops_timebase) {
- add_powernv_state(nr_idle_states, names[i],
+ add_powernv_state(nr_idle_states, state->name,
CPUIDLE_FLAG_NONE, stop_loop,
target_residency, exit_latency,
- psscr_val[i], psscr_mask[i]);
+ state->psscr_val,
+ state->psscr_mask);
}

/*
@@ -443,20 +349,19 @@ static int powernv_add_idle_states(void)
* within this config dependency check.
*/
#ifdef CONFIG_TICK_ONESHOT
- else if (flags[i] & OPAL_PM_SLEEP_ENABLED ||
- flags[i] & OPAL_PM_SLEEP_ENABLED_ER1) {
- if (!rc)
- target_residency = 300000;
+ else if (state->flags & OPAL_PM_SLEEP_ENABLED ||
+ state->flags & OPAL_PM_SLEEP_ENABLED_ER1) {
/* Add FASTSLEEP state */
add_powernv_state(nr_idle_states, "FastSleep",
CPUIDLE_FLAG_TIMER_STOP,
fastsleep_loop,
target_residency, exit_latency, 0, 0);
} else if (has_stop_states && stops_timebase) {
- add_powernv_state(nr_idle_states, names[i],
+ add_powernv_state(nr_idle_states, state->name,
CPUIDLE_FLAG_TIMER_STOP, stop_loop,
target_residency, exit_latency,
- psscr_val[i], psscr_mask[i]);
+ state->psscr_val,
+ state->psscr_mask);
}
#endif
else
--
2.18.0.rc2.85.g1fb9df7