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cpuidle: powernv: Avoid endianness conversions while parsing DT 

We currently read the information about idle states from the DT
so as to populate the cpuidle table. Use those APIs to read from
the DT that can avoid endianness conversions of the property values
in the cpuidle driver.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
hifive-unleashed-5.1
Preeti U Murthy 2015-02-18 23:24:53 -06:00 committed by Rafael J. Wysocki
parent 92c83ff5b4
commit 70734a786a
1 changed files with 16 additions and 13 deletions
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29
drivers/cpuidle/cpuidle-powernv.c
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@ -159,9 +159,7 @@ static int powernv_add_idle_states(void)
struct device_node *power_mgt;
int nr_idle_states = 1; /* Snooze */
int dt_idle_states;
const __be32 *idle_state_flags;
u32 len_flags, flags;
u32 *latency_ns, *residency_ns;
u32 *latency_ns, *residency_ns, *flags;
int i, rc;
/* Currently we have snooze statically defined */
@ -172,14 +170,19 @@ static int powernv_add_idle_states(void)
goto out;
}
idle_state_flags = of_get_property(power_mgt,
"ibm,cpu-idle-state-flags", &len_flags);
if (!idle_state_flags) {
pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-flags in DT\n");
/* 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;
}
dt_idle_states = len_flags / sizeof(u32);
flags = kzalloc(sizeof(*flags) * dt_idle_states, GFP_KERNEL);
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_free_flags;
}
latency_ns = kzalloc(sizeof(*latency_ns) * dt_idle_states, GFP_KERNEL);
rc = of_property_read_u32_array(power_mgt,
@ -195,21 +198,19 @@ static int powernv_add_idle_states(void)
for (i = 0; i < dt_idle_states; i++) {
flags = be32_to_cpu(idle_state_flags[i]);
/*
* Cpuidle accepts exit_latency and target_residency in us.
* Use default target_residency values if f/w does not expose it.
*/
if (flags & OPAL_PM_NAP_ENABLED) {
if (flags[i] & OPAL_PM_NAP_ENABLED) {
/* Add NAP state */
strcpy(powernv_states[nr_idle_states].name, "Nap");
strcpy(powernv_states[nr_idle_states].desc, "Nap");
powernv_states[nr_idle_states].flags = 0;
powernv_states[nr_idle_states].target_residency = 100;
powernv_states[nr_idle_states].enter = &nap_loop;
} else if (flags & OPAL_PM_SLEEP_ENABLED ||
flags & OPAL_PM_SLEEP_ENABLED_ER1) {
} else if (flags[i] & OPAL_PM_SLEEP_ENABLED ||
flags[i] & OPAL_PM_SLEEP_ENABLED_ER1) {
/* Add FASTSLEEP state */
strcpy(powernv_states[nr_idle_states].name, "FastSleep");
strcpy(powernv_states[nr_idle_states].desc, "FastSleep");
@ -232,6 +233,8 @@ static int powernv_add_idle_states(void)
kfree(residency_ns);
out_free_latency:
kfree(latency_ns);
out_free_flags:
kfree(flags);
out:
return nr_idle_states;
}