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authorMauro Carvalho Chehab <mchehab@redhat.com>2013-01-11 13:28:19 -0200
committerMauro Carvalho Chehab <mchehab@redhat.com>2013-01-11 13:28:19 -0200
commit734d1ece37fbf3d2ddfc71bc6c69e0fe35f02542 (patch)
treec4805dd7e746b1feb9e09e9849f3245d0b2c0c6b /drivers/thermal/fair_share.c
parent216c82c6aba63eeb49d7654b448e0d47bea255bb (diff)
parent9931faca02c604c22335f5a935a501bb2ace6e20 (diff)
Merge tag 'v3.8-rc3' into v4l_for_linus
Linux 3.8-rc3 * tag 'v3.8-rc3': (11110 commits) Linux 3.8-rc3 mm: reinstante dropped pmd_trans_splitting() check cred: Remove tgcred pointer from struct cred drm/ttm: fix fence locking in ttm_buffer_object_transfer ARM: clps711x: Fix bad merge of clockevents setup ARM: highbank: save and restore L2 cache and GIC on suspend ARM: highbank: add a power request clear ARM: highbank: fix secondary boot and hotplug ARM: highbank: fix typos with hignbank in power request functions ARM: dts: fix highbank cpu mpidr values ARM: dts: add device_type prop to cpu nodes on Calxeda platforms drm/prime: drop reference on imported dma-buf come from gem xen/netfront: improve truesize tracking ARM: mx5: Fix MX53 flexcan2 clock ARM: OMAP2+: am33xx-hwmod: Fix wrongly terminated am33xx_usbss_mpu_irqs array sctp: fix Kconfig bug in default cookie hmac selection EDAC: Cleanup device deregistering path EDAC: Fix EDAC Kconfig menu EDAC: Fix kernel panic on module unloading ALSA: hda - add mute LED for HP Pavilion 17 (Realtek codec) ...
Diffstat (limited to 'drivers/thermal/fair_share.c')
-rw-r--r--drivers/thermal/fair_share.c133
1 files changed, 133 insertions, 0 deletions
diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c
new file mode 100644
index 00000000000..792479f2b64
--- /dev/null
+++ b/drivers/thermal/fair_share.c
@@ -0,0 +1,133 @@
+/*
+ * fair_share.c - A simple weight based Thermal governor
+ *
+ * Copyright (C) 2012 Intel Corp
+ * Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/thermal.h>
+
+#include "thermal_core.h"
+
+/**
+ * get_trip_level: - obtains the current trip level for a zone
+ * @tz: thermal zone device
+ */
+static int get_trip_level(struct thermal_zone_device *tz)
+{
+ int count = 0;
+ unsigned long trip_temp;
+
+ if (tz->trips == 0 || !tz->ops->get_trip_temp)
+ return 0;
+
+ for (count = 0; count < tz->trips; count++) {
+ tz->ops->get_trip_temp(tz, count, &trip_temp);
+ if (tz->temperature < trip_temp)
+ break;
+ }
+ return count;
+}
+
+static long get_target_state(struct thermal_zone_device *tz,
+ struct thermal_cooling_device *cdev, int weight, int level)
+{
+ unsigned long max_state;
+
+ cdev->ops->get_max_state(cdev, &max_state);
+
+ return (long)(weight * level * max_state) / (100 * tz->trips);
+}
+
+/**
+ * fair_share_throttle - throttles devices asscciated with the given zone
+ * @tz - thermal_zone_device
+ *
+ * Throttling Logic: This uses three parameters to calculate the new
+ * throttle state of the cooling devices associated with the given zone.
+ *
+ * Parameters used for Throttling:
+ * P1. max_state: Maximum throttle state exposed by the cooling device.
+ * P2. weight[i]/100:
+ * How 'effective' the 'i'th device is, in cooling the given zone.
+ * P3. cur_trip_level/max_no_of_trips:
+ * This describes the extent to which the devices should be throttled.
+ * We do not want to throttle too much when we trip a lower temperature,
+ * whereas the throttling is at full swing if we trip critical levels.
+ * (Heavily assumes the trip points are in ascending order)
+ * new_state of cooling device = P3 * P2 * P1
+ */
+static int fair_share_throttle(struct thermal_zone_device *tz, int trip)
+{
+ const struct thermal_zone_params *tzp;
+ struct thermal_cooling_device *cdev;
+ struct thermal_instance *instance;
+ int i;
+ int cur_trip_level = get_trip_level(tz);
+
+ if (!tz->tzp || !tz->tzp->tbp)
+ return -EINVAL;
+
+ tzp = tz->tzp;
+
+ for (i = 0; i < tzp->num_tbps; i++) {
+ if (!tzp->tbp[i].cdev)
+ continue;
+
+ cdev = tzp->tbp[i].cdev;
+ instance = get_thermal_instance(tz, cdev, trip);
+ if (!instance)
+ continue;
+
+ instance->target = get_target_state(tz, cdev,
+ tzp->tbp[i].weight, cur_trip_level);
+
+ instance->cdev->updated = false;
+ thermal_cdev_update(cdev);
+ }
+ return 0;
+}
+
+static struct thermal_governor thermal_gov_fair_share = {
+ .name = "fair_share",
+ .throttle = fair_share_throttle,
+ .owner = THIS_MODULE,
+};
+
+static int __init thermal_gov_fair_share_init(void)
+{
+ return thermal_register_governor(&thermal_gov_fair_share);
+}
+
+static void __exit thermal_gov_fair_share_exit(void)
+{
+ thermal_unregister_governor(&thermal_gov_fair_share);
+}
+
+/* This should load after thermal framework */
+fs_initcall(thermal_gov_fair_share_init);
+module_exit(thermal_gov_fair_share_exit);
+
+MODULE_AUTHOR("Durgadoss R");
+MODULE_DESCRIPTION("A simple weight based thermal throttling governor");
+MODULE_LICENSE("GPL");