Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

[linux-2.6-block.git] / drivers / cpuidle / cpuidle-powernv.c

diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c
index 3a763a823416e403f1eb4212dcf5b08bdc2ac207..f7ca891b5b59ff4681edad72bd5392b9f1081d1f 100644 (file)
--- a/drivers/cpuidle/cpuidle-powernv.c
+++ b/drivers/cpuidle/cpuidle-powernv.c
@@ -20,6 +20,8 @@
 #include <asm/opal.h>
 #include <asm/runlatch.h>
 
+#define POWERNV_THRESHOLD_LATENCY_NS 200000
+
 struct cpuidle_driver powernv_idle_driver = {
        .name             = "powernv_idle",
        .owner            = THIS_MODULE,
@@ -27,6 +29,9 @@ struct cpuidle_driver powernv_idle_driver = {
 
 static int max_idle_state;
 static struct cpuidle_state *cpuidle_state_table;
+
+static u64 stop_psscr_table[CPUIDLE_STATE_MAX];
+
 static u64 snooze_timeout;
 static bool snooze_timeout_en;
 
@@ -91,6 +96,17 @@ static int fastsleep_loop(struct cpuidle_device *dev,
        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]);
+       ppc64_runlatch_on();
+       return index;
+}
+
 /*
  * States for dedicated partition case.
  */
@@ -100,7 +116,7 @@ static struct cpuidle_state powernv_states[CPUIDLE_STATE_MAX] = {
                .desc = "snooze",
                .exit_latency = 0,
                .target_residency = 0,
-               .enter = &snooze_loop },
+               .enter = snooze_loop },
 };
 
 static int powernv_cpuidle_add_cpu_notifier(struct notifier_block *n,
@@ -166,7 +182,11 @@ static int powernv_add_idle_states(void)
        struct device_node *power_mgt;
        int nr_idle_states = 1; /* Snooze */
        int dt_idle_states;
-       u32 *latency_ns, *residency_ns, *flags;
+       u32 latency_ns[CPUIDLE_STATE_MAX];
+       u32 residency_ns[CPUIDLE_STATE_MAX];
+       u32 flags[CPUIDLE_STATE_MAX];
+       u64 psscr_val[CPUIDLE_STATE_MAX];
+       const char *names[CPUIDLE_STATE_MAX];
        int i, rc;
 
        /* Currently we have snooze statically defined */
@@ -184,26 +204,55 @@ static int powernv_add_idle_states(void)
                goto out;
        }
 
-       flags = kzalloc(sizeof(*flags) * dt_idle_states, GFP_KERNEL);
+       /*
+        * 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_free_flags;
+               goto out;
        }
 
-       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) {
+       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_free_latency;
+               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;
        }
 
-       residency_ns = kzalloc(sizeof(*residency_ns) * dt_idle_states, GFP_KERNEL);
+       /*
+        * If the idle states use stop instruction, probe for psscr values
+        * which are necessary to specify required stop level.
+        */
+       if (flags[0] & (OPAL_PM_STOP_INST_FAST | OPAL_PM_STOP_INST_DEEP))
+               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-states-psscr in DT\n");
+                       goto out;
+               }
+
        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++) {
+               /*
+                * 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;
 
                /*
                 * Cpuidle accepts exit_latency and target_residency in us.
@@ -215,7 +264,17 @@ static int powernv_add_idle_states(void)
                        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;
+                       powernv_states[nr_idle_states].enter = nap_loop;
+               } else if ((flags[i] & OPAL_PM_STOP_INST_FAST) &&
+                               !(flags[i] & OPAL_PM_TIMEBASE_STOP)) {
+                       strncpy(powernv_states[nr_idle_states].name,
+                               names[i], CPUIDLE_NAME_LEN);
+                       strncpy(powernv_states[nr_idle_states].desc,
+                               names[i], CPUIDLE_NAME_LEN);
+                       powernv_states[nr_idle_states].flags = 0;
+
+                       powernv_states[nr_idle_states].enter = stop_loop;
+                       stop_psscr_table[nr_idle_states] = psscr_val[i];
                }
 
                /*
@@ -230,7 +289,17 @@ static int powernv_add_idle_states(void)
                        strcpy(powernv_states[nr_idle_states].desc, "FastSleep");
                        powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIMER_STOP;
                        powernv_states[nr_idle_states].target_residency = 300000;
-                       powernv_states[nr_idle_states].enter = &fastsleep_loop;
+                       powernv_states[nr_idle_states].enter = fastsleep_loop;
+               } else if ((flags[i] & OPAL_PM_STOP_INST_DEEP) &&
+                               (flags[i] & OPAL_PM_TIMEBASE_STOP)) {
+                       strncpy(powernv_states[nr_idle_states].name,
+                               names[i], CPUIDLE_NAME_LEN);
+                       strncpy(powernv_states[nr_idle_states].desc,
+                               names[i], CPUIDLE_NAME_LEN);
+
+                       powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIMER_STOP;
+                       powernv_states[nr_idle_states].enter = stop_loop;
+                       stop_psscr_table[nr_idle_states] = psscr_val[i];
                }
 #endif
                powernv_states[nr_idle_states].exit_latency =
@@ -243,12 +312,6 @@ static int powernv_add_idle_states(void)
 
                nr_idle_states++;
        }
-
-       kfree(residency_ns);
-out_free_latency:
-       kfree(latency_ns);
-out_free_flags:
-       kfree(flags);
 out:
        return nr_idle_states;
 }