| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Fri, 29 Nov 2013 16:13:51 +0530
From: Preeti U Murthy <preeti@...ux.vnet.ibm.com>
To: fweisbec@...il.com, paul.gortmaker@...driver.com, paulus@...ba.org,
shangw@...ux.vnet.ibm.com, rjw@...k.pl, galak@...nel.crashing.org,
benh@...nel.crashing.org, paulmck@...ux.vnet.ibm.com,
arnd@...db.de, linux-pm@...r.kernel.org, rostedt@...dmis.org,
michael@...erman.id.au, john.stultz@...aro.org, tglx@...utronix.de,
chenhui.zhao@...escale.com, deepthi@...ux.vnet.ibm.com,
r58472@...escale.com, geoff@...radead.org,
linux-kernel@...r.kernel.org, srivatsa.bhat@...ux.vnet.ibm.com,
schwidefsky@...ibm.com, svaidy@...ux.vnet.ibm.com,
linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH V4 9/9] cpuidle/powernv: Parse device tree to setup idle
states
Add deep idle states such as nap and fast sleep to the cpuidle state table
only if they are discovered from the device tree during cpuidle initialization.
Signed-off-by: Preeti U. Murthy <preeti@...ux.vnet.ibm.com>
---
drivers/cpuidle/cpuidle-powerpc-book3s.c | 81 ++++++++++++++++++++++++------
1 file changed, 64 insertions(+), 17 deletions(-)
diff --git a/drivers/cpuidle/cpuidle-powerpc-book3s.c b/drivers/cpuidle/cpuidle-powerpc-book3s.c
index 59cd529..b80ee9b 100644
--- a/drivers/cpuidle/cpuidle-powerpc-book3s.c
+++ b/drivers/cpuidle/cpuidle-powerpc-book3s.c
@@ -18,6 +18,7 @@
#include <linux/ktime.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
+#include <linux/of.h>
#include <asm/paca.h>
#include <asm/reg.h>
@@ -27,6 +28,12 @@
#include <asm/time.h>
#include <asm/plpar_wrappers.h>
+/* Flags and constants used in PowerNV platform */
+
+#define MAX_POWERNV_IDLE_STATES 8
+#define IDLE_USE_INST_NAP 0x00010000 /* Use nap instruction */
+#define IDLE_USE_INST_SLEEP 0x00020000 /* Use sleep instruction */
+
struct cpuidle_driver powerpc_book3s_idle_driver = {
.name = "powerpc_book3s_idle",
.owner = THIS_MODULE,
@@ -327,7 +334,7 @@ static struct cpuidle_state shared_states[] = {
.enter = &shared_cede_loop },
};
-static struct cpuidle_state powernv_states[] = {
+static struct cpuidle_state powernv_states[MAX_POWERNV_IDLE_STATES] = {
{ /* Snooze */
.name = "snooze",
.desc = "snooze",
@@ -335,20 +342,6 @@ static struct cpuidle_state powernv_states[] = {
.exit_latency = 0,
.target_residency = 0,
.enter = &snooze_loop },
- { /* NAP */
- .name = "NAP",
- .desc = "NAP",
- .flags = CPUIDLE_FLAG_TIME_VALID,
- .exit_latency = 10,
- .target_residency = 100,
- .enter = &nap_loop },
- { /* Fastsleep */
- .name = "fastsleep",
- .desc = "fastsleep",
- .flags = CPUIDLE_FLAG_TIME_VALID,
- .exit_latency = 10,
- .target_residency = 100,
- .enter = &fastsleep_loop },
};
void update_smt_snooze_delay(int cpu, int residency)
@@ -418,6 +411,60 @@ static struct notifier_block setup_hotplug_notifier = {
.notifier_call = powerpc_book3s_cpuidle_add_cpu_notifier,
};
+static int powernv_add_idle_states(void)
+{
+ struct device_node *power_mgt;
+ struct property *prop;
+ int nr_idle_states = 1; /* Snooze */
+ int dt_idle_states;
+ u32 *flags;
+ int i;
+
+ /* 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;
+ }
+
+ prop = of_find_property(power_mgt, "ibm,cpu-idle-state-flags", NULL);
+ if (!prop) {
+ pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-flags\n");
+ return nr_idle_states;
+ }
+
+ dt_idle_states = prop->length / sizeof(u32);
+ flags = (u32 *) prop->value;
+
+ for (i = 0; i < dt_idle_states; i++) {
+
+ if (flags[i] & IDLE_USE_INST_NAP) {
+ /* 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 = CPUIDLE_FLAG_TIME_VALID;
+ powernv_states[nr_idle_states].exit_latency = 10;
+ powernv_states[nr_idle_states].target_residency = 100;
+ powernv_states[nr_idle_states].enter = &nap_loop;
+ nr_idle_states++;
+ }
+
+ if (flags[i] & IDLE_USE_INST_SLEEP) {
+ /* 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_TIME_VALID;
+ powernv_states[nr_idle_states].exit_latency = 300;
+ powernv_states[nr_idle_states].target_residency = 1000000;
+ powernv_states[nr_idle_states].enter = &fastsleep_loop;
+ nr_idle_states++;
+ }
+ }
+
+ return nr_idle_states;
+}
+
/*
* powerpc_book3s_cpuidle_driver_init()
*/
@@ -448,7 +495,6 @@ static int powerpc_book3s_cpuidle_driver_init(void)
*/
static int powerpc_book3s_idle_probe(void)
{
-
if (cpuidle_disable != IDLE_NO_OVERRIDE)
return -ENODEV;
@@ -463,7 +509,8 @@ static int powerpc_book3s_idle_probe(void)
} else if (firmware_has_feature(FW_FEATURE_OPALv3)) {
cpuidle_state_table = powernv_states;
- max_idle_state = ARRAY_SIZE(powernv_states);
+ /* Device tree can indicate more idle states */
+ max_idle_state = powernv_add_idle_states();
} else
return -ENODEV;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists