aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/cpuidle/cpuidle-powernv.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/cpuidle/cpuidle-powernv.c')
-rw-r--r--drivers/cpuidle/cpuidle-powernv.c84
1 files changed, 49 insertions, 35 deletions
diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c
index aedec0957934..59372077ec7c 100644
--- a/drivers/cpuidle/cpuidle-powernv.c
+++ b/drivers/cpuidle/cpuidle-powernv.c
@@ -13,6 +13,7 @@
#include <linux/notifier.h>
#include <linux/clockchips.h>
#include <linux/of.h>
+#include <linux/slab.h>
#include <asm/machdep.h>
#include <asm/firmware.h>
@@ -158,70 +159,83 @@ 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;
- const __be32 *idle_state_latency;
- u32 len_flags, flags, latency_ns;
- int i;
+ u32 *latency_ns, *residency_ns, *flags;
+ 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");
- return nr_idle_states;
+ goto out;
}
- idle_state_flags = of_get_property(power_mgt, "ibm,cpu-idle-state-flags", &len_flags);
- if (!idle_state_flags) {
- pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-flags\n");
- return nr_idle_states;
+ /* 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;
}
- idle_state_latency = of_get_property(power_mgt,
- "ibm,cpu-idle-state-latencies-ns", NULL);
- if (!idle_state_latency) {
- pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-latencies-ns\n");
- return nr_idle_states;
+ 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;
}
- dt_idle_states = len_flags / sizeof(u32);
+ latency_ns = kzalloc(sizeof(*latency_ns) * dt_idle_states, GFP_KERNEL);
+ rc = of_property_read_u32_array(power_mgt,
+ "ibm,cpu-idle-state-latencies-ns", latency_ns, dt_idle_states);
+ if (rc) {
+ pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
+ goto out_free_latency;
+ }
- for (i = 0; i < dt_idle_states; i++) {
+ residency_ns = kzalloc(sizeof(*residency_ns) * dt_idle_states, GFP_KERNEL);
+ rc = of_property_read_u32_array(power_mgt,
+ "ibm,cpu-idle-state-residency-ns", residency_ns, dt_idle_states);
- flags = be32_to_cpu(idle_state_flags[i]);
+ for (i = 0; i < dt_idle_states; i++) {
- /* Cpuidle accepts exit_latency in us and we estimate
- * target residency to be 10x exit_latency
+ /*
+ * Cpuidle accepts exit_latency and target_residency in us.
+ * Use default target_residency values if f/w does not expose it.
*/
- latency_ns = be32_to_cpu(idle_state_latency[i]);
- 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].exit_latency =
- ((unsigned int)latency_ns) / 1000;
- powernv_states[nr_idle_states].target_residency =
- ((unsigned int)latency_ns / 100);
+ powernv_states[nr_idle_states].target_residency = 100;
powernv_states[nr_idle_states].enter = &nap_loop;
- nr_idle_states++;
- }
-
- 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");
powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIMER_STOP;
- powernv_states[nr_idle_states].exit_latency =
- ((unsigned int)latency_ns) / 1000;
- powernv_states[nr_idle_states].target_residency =
- ((unsigned int)latency_ns / 100);
+ powernv_states[nr_idle_states].target_residency = 300000;
powernv_states[nr_idle_states].enter = &fastsleep_loop;
- nr_idle_states++;
}
+
+ powernv_states[nr_idle_states].exit_latency =
+ ((unsigned int)latency_ns[i]) / 1000;
+
+ if (!rc) {
+ powernv_states[nr_idle_states].target_residency =
+ ((unsigned int)residency_ns[i]) / 1000;
+ }
+
+ nr_idle_states++;
}
+ kfree(residency_ns);
+out_free_latency:
+ kfree(latency_ns);
+out_free_flags:
+ kfree(flags);
+out:
return nr_idle_states;
}

Privacy Policy