[PATCH 03/14] iwlwifi: Thermal Throttling Management - Part 1

Reinette Chatre
2009-07-24T18:13:15Z

From: Wey-Yi Guy <wey-yi.w.guy@intel.com>

Part 1 of Thermal Throttling Management -

Thermal Throttling feature is used to put NIC into low power state when
driver detect the Radio temperature reach pre-defined threshold

Two Thermal Throttling Management Methods; this patch introduce the
Legacy Thermal Management:
IWL_TI_0: normal temperature, system power state
IWL_TI_1: high temperature detect, low power state
IWL_TI_2: higher temperature detected, lower power state
IWL_TI_CT_KILL: critical temperature detected, lowest power state

Once get into CT_KILL state, uCode go into sleep, driver will stop all
the active queues, then move to IWL_TI_CT_KILL state; also set up 5
seconds timer to toggle CSR flag, uCode wake up upon CSR flag change,
then measure the temperature.
If temperature is above CT_KILL exit threshold, uCode go backto sleep;
if temperature is below CT_KILL exit threshold, uCode send Card State
Notification response with appropriate CT_KILL status flag, and uCode
remain awake, Driver receive Card State Notification Response and update
the card temperature to the CT_KILL exit threshold.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
---
drivers/net/wireless/iwlwifi/iwl-4965.c | 1 +
drivers/net/wireless/iwlwifi/iwl-5000.c | 1 +
drivers/net/wireless/iwlwifi/iwl-agn.c | 19 +--
drivers/net/wireless/iwlwifi/iwl-core.c | 1 +
drivers/net/wireless/iwlwifi/iwl-power.c | 249 ++++++++++++++++++++++++++++++
drivers/net/wireless/iwlwifi/iwl-power.h | 42 +++++
6 files changed, 301 insertions(+), 12 deletions(-)

diff --git a/drivers/net/wireless/iwlwifi/iwl-4965.c b/drivers/net/wireless/iwlwifi/iwl-4965.c
index 23925bd..6702148 100644
--- a/drivers/net/wireless/iwlwifi/iwl-4965.c
+++ b/drivers/net/wireless/iwlwifi/iwl-4965.c
@@ -1797,6 +1797,7 @@ static void iwl4965_temperature_calib(struct iwl_priv *priv)
}

priv->temperature = temp;
+ iwl_tt_handler(priv);
set_bit(STATUS_TEMPERATURE, &priv->status);

if (!priv->disable_tx_power_cal &&
diff --git a/drivers/net/wireless/iwlwifi/iwl-5000.c b/drivers/net/wireless/iwlwifi/iwl-5000.c
index 076acb1..ddd64fe 100644
--- a/drivers/net/wireless/iwlwifi/iwl-5000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-5000.c
@@ -1405,6 +1405,7 @@ void iwl5000_temperature(struct iwl_priv *priv)
{
/* store temperature from statistics (in Celsius) */
priv->temperature = le32_to_cpu(priv->statistics.general.temperature);
+ iwl_tt_handler(priv);
}

static void iwl5150_temperature(struct iwl_priv *priv)
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 44c7f23..23ae991 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -637,7 +637,6 @@ static void iwl_rx_card_state_notif(struct iwl_priv *priv,
struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
u32 flags = le32_to_cpu(pkt->u.card_state_notif.flags);
unsigned long status = priv->status;
- unsigned long reg_flags;

IWL_DEBUG_RF_KILL(priv, "Card state received: HW:%s SW:%s\n",
(flags & HW_CARD_DISABLED) ? "Kill" : "On",
@@ -657,19 +656,12 @@ static void iwl_rx_card_state_notif(struct iwl_priv *priv,
CSR_UCODE_DRV_GP1_BIT_CMD_BLOCKED);
iwl_write_direct32(priv, HBUS_TARG_MBX_C,
HBUS_TARG_MBX_C_REG_BIT_CMD_BLOCKED);
-
- }
-
- if (flags & RF_CARD_DISABLED) {
- iwl_write32(priv, CSR_UCODE_DRV_GP1_SET,
- CSR_UCODE_DRV_GP1_REG_BIT_CT_KILL_EXIT);
- iwl_read32(priv, CSR_UCODE_DRV_GP1);
- spin_lock_irqsave(&priv->reg_lock, reg_flags);
- if (!iwl_grab_nic_access(priv))
- iwl_release_nic_access(priv);
- spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
}
+ if (flags & RF_CARD_DISABLED)
+ iwl_tt_enter_ct_kill(priv);
}
+ if (!(flags & RF_CARD_DISABLED))
+ iwl_tt_exit_ct_kill(priv);

if (flags & HW_CARD_DISABLED)
set_bit(STATUS_RF_KILL_HW, &priv->status);
@@ -3015,6 +3007,7 @@ static int iwl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
test_bit(STATUS_RF_KILL_HW, &priv->status));

iwl_power_initialize(priv);
+ iwl_tt_initialize(priv);
return 0;

out_remove_sysfs:
@@ -3067,6 +3060,8 @@ static void __devexit iwl_pci_remove(struct pci_dev *pdev)
iwl_down(priv);
}

+ iwl_tt_exit(priv);
+
/* make sure we flush any pending irq or
* tasklet for the driver
*/
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index 5ef3c37..d8aeb24 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -2232,6 +2232,7 @@ void iwl_rf_kill_ct_config(struct iwl_priv *priv)
iwl_write32(priv, CSR_UCODE_DRV_GP1_CLR,
CSR_UCODE_DRV_GP1_REG_BIT_CT_KILL_EXIT);
spin_unlock_irqrestore(&priv->lock, flags);
+ priv->power_data.ct_kill_toggle = false;

switch (priv->hw_rev & CSR_HW_REV_TYPE_MSK) {
case CSR_HW_REV_TYPE_1000:
diff --git a/drivers/net/wireless/iwlwifi/iwl-power.c b/drivers/net/wireless/iwlwifi/iwl-power.c
index f2ea3f0..d7fdb58 100644
--- a/drivers/net/wireless/iwlwifi/iwl-power.c
+++ b/drivers/net/wireless/iwlwifi/iwl-power.c
@@ -36,6 +36,7 @@
#include "iwl-eeprom.h"
#include "iwl-dev.h"
#include "iwl-core.h"
+#include "iwl-io.h"
#include "iwl-commands.h"
#include "iwl-debug.h"
#include "iwl-power.h"
@@ -211,6 +212,7 @@ int iwl_power_update_mode(struct iwl_priv *priv, bool force)
{
struct iwl_power_mgr *setting = &(priv->power_data);
int ret = 0;
+ struct iwl_tt_mgmt *tt = &priv->power_data.tt;
u16 uninitialized_var(final_mode);
bool update_chains;

@@ -223,6 +225,10 @@ int iwl_power_update_mode(struct iwl_priv *priv, bool force)
if (setting->power_disabled)
final_mode = IWL_POWER_MODE_CAM;

+ if (tt->state >= IWL_TI_1) {
+ /* TT power setting overwrite user & system power setting */
+ final_mode = tt->tt_power_mode;
+ }
if (iwl_is_ready_rf(priv) &&
((setting->power_mode != final_mode) || force)) {
struct iwl_powertable_cmd cmd;
@@ -267,6 +273,249 @@ int iwl_power_set_user_mode(struct iwl_priv *priv, u16 mode)
}
EXPORT_SYMBOL(iwl_power_set_user_mode);

+#define CT_KILL_EXIT_DURATION (5) /* 5 seconds duration */
+
+/*
+ * toggle the bit to wake up uCode and check the temperature
+ * if the temperature is below CT, uCode will stay awake and send card
+ * state notification with CT_KILL bit clear to inform Thermal Throttling
+ * Management to change state. Otherwise, uCode will go back to sleep
+ * without doing anything, driver should continue the 5 seconds timer
+ * to wake up uCode for temperature check until temperature drop below CT
+ */
+static void iwl_tt_check_exit_ct_kill(unsigned long data)
+{
+ struct iwl_priv *priv = (struct iwl_priv *)data;
+ struct iwl_tt_mgmt *tt = &priv->power_data.tt;
+ unsigned long flags;
+
+ if (test_bit(STATUS_EXIT_PENDING, &priv->status))
+ return;
+
+ if (tt->state == IWL_TI_CT_KILL) {
+ if (priv->power_data.ct_kill_toggle) {
+ iwl_write32(priv, CSR_UCODE_DRV_GP1_CLR,
+ CSR_UCODE_DRV_GP1_REG_BIT_CT_KILL_EXIT);
+ priv->power_data.ct_kill_toggle = false;
+ } else {
+ iwl_write32(priv, CSR_UCODE_DRV_GP1_SET,
+ CSR_UCODE_DRV_GP1_REG_BIT_CT_KILL_EXIT);
+ priv->power_data.ct_kill_toggle = true;
+ }
+ iwl_read32(priv, CSR_UCODE_DRV_GP1);
+ spin_lock_irqsave(&priv->reg_lock, flags);
+ if (!iwl_grab_nic_access(priv))
+ iwl_release_nic_access(priv);
+ spin_unlock_irqrestore(&priv->reg_lock, flags);
+
+ /* Reschedule the ct_kill timer to occur in
+ * CT_KILL_EXIT_DURATION seconds to ensure we get a
+ * thermal update */
+ mod_timer(&priv->power_data.ct_kill_exit_tm, jiffies +
+ CT_KILL_EXIT_DURATION * HZ);
+ }
+}
+
+static void iwl_perform_ct_kill_task(struct iwl_priv *priv,
+ bool stop)
+{
+ if (stop) {
+ IWL_DEBUG_POWER(priv, "Stop all queues\n");
+ if (priv->mac80211_registered)
+ ieee80211_stop_queues(priv->hw);
+ IWL_DEBUG_POWER(priv,
+ "Schedule 5 seconds CT_KILL Timer\n");
+ mod_timer(&priv->power_data.ct_kill_exit_tm, jiffies +
+ CT_KILL_EXIT_DURATION * HZ);
+ } else {
+ IWL_DEBUG_POWER(priv, "Wake all queues\n");
+ if (priv->mac80211_registered)
+ ieee80211_wake_queues(priv->hw);
+ }
+}
+
+#define IWL_MINIMAL_POWER_THRESHOLD (CT_KILL_THRESHOLD_LEGACY)
+#define IWL_REDUCED_PERFORMANCE_THRESHOLD_2 (100)
+#define IWL_REDUCED_PERFORMANCE_THRESHOLD_1 (90)
+
+/*
+ * Legacy thermal throttling
+ * 1) Avoid NIC destruction due to high temperatures
+ * Chip will identify dangerously high temperatures that can
+ * harm the device and will power down
+ * 2) Avoid the NIC power down due to high temperature
+ * Throttle early enough to lower the power consumption before
+ * drastic steps are needed
+ */
+static void iwl_legacy_tt_handler(struct iwl_priv *priv, s32 temp)
+{
+ struct iwl_tt_mgmt *tt = &priv->power_data.tt;
+ enum iwl_tt_state new_state;
+ struct iwl_power_mgr *setting = &priv->power_data;
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+ if ((tt->tt_previous_temp) &&
+ (temp > tt->tt_previous_temp) &&
+ ((temp - tt->tt_previous_temp) >
+ IWL_TT_INCREASE_MARGIN)) {
+ IWL_DEBUG_POWER(priv,
+ "Temperature increase %d degree Celsius\n",
+ (temp - tt->tt_previous_temp));
+ }
+#endif
+ /* in Celsius */
+ if (temp >= IWL_MINIMAL_POWER_THRESHOLD)
+ new_state = IWL_TI_CT_KILL;
+ else if (temp >= IWL_REDUCED_PERFORMANCE_THRESHOLD_2)
+ new_state = IWL_TI_2;
+ else if (temp >= IWL_REDUCED_PERFORMANCE_THRESHOLD_1)
+ new_state = IWL_TI_1;
+ else
+ new_state = IWL_TI_0;
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+ tt->tt_previous_temp = temp;
+#endif
+ if (tt->state != new_state) {
+ if (tt->state == IWL_TI_0) {
+ tt->sys_power_mode = setting->power_mode;
+ IWL_DEBUG_POWER(priv, "current power mode: %u\n",
+ setting->power_mode);
+ }
+ switch (new_state) {
+ case IWL_TI_0:
+ /* when system ready to go back to IWL_TI_0 state
+ * using system power mode instead of TT power mode
+ * revert back to the orginal power mode which was saved
+ * before enter Thermal Throttling state
+ * update priv->power_data.user_power_setting to the
+ * required power mode to make sure
+ * iwl_power_update_mode() will update power correctly.
+ */
+ priv->power_data.user_power_setting =
+ tt->sys_power_mode;
+ tt->tt_power_mode = tt->sys_power_mode;
+ break;
+ case IWL_TI_1:
+ tt->tt_power_mode = IWL_POWER_INDEX_3;
+ break;
+ case IWL_TI_2:
+ tt->tt_power_mode = IWL_POWER_INDEX_4;
+ break;
+ default:
+ tt->tt_power_mode = IWL_POWER_INDEX_5;
+ break;
+ }
+ if (iwl_power_update_mode(priv, true)) {
+ /* TT state not updated
+ * try again during next temperature read
+ */
+ IWL_ERR(priv, "Cannot update power mode, "
+ "TT state not updated\n");
+ } else {
+ if (new_state == IWL_TI_CT_KILL)
+ iwl_perform_ct_kill_task(priv, true);
+ else if (tt->state == IWL_TI_CT_KILL &&
+ new_state != IWL_TI_CT_KILL)
+ iwl_perform_ct_kill_task(priv, false);
+ tt->state = new_state;
+ IWL_DEBUG_POWER(priv, "Temperature state changed %u\n",
+ tt->state);
+ IWL_DEBUG_POWER(priv, "Power Index change to %u\n",
+ tt->tt_power_mode);
+ }
+ }
+}
+
+/* Card State Notification indicated reach critical temperature
+ * if PSP not enable, no Thermal Throttling function will be performed
+ * just set the GP1 bit to acknowledge the event
+ * otherwise, go into IWL_TI_CT_KILL state
+ * since Card State Notification will not provide any temperature reading
+ * so just pass the CT_KILL temperature to iwl_legacy_tt_handler()
+ */
+void iwl_tt_enter_ct_kill(struct iwl_priv *priv)
+{
+ struct iwl_tt_mgmt *tt = &priv->power_data.tt;
+
+ if (test_bit(STATUS_EXIT_PENDING, &priv->status))
+ return;
+
+ if (tt->state != IWL_TI_CT_KILL) {
+ IWL_ERR(priv, "Device reached critical temperature "
+ "- ucode going to sleep!\n");
+ iwl_legacy_tt_handler(priv, IWL_MINIMAL_POWER_THRESHOLD);
+ }
+}
+EXPORT_SYMBOL(iwl_tt_enter_ct_kill);
+
+/* Card State Notification indicated out of critical temperature
+ * since Card State Notification will not provide any temperature reading
+ * so pass the IWL_REDUCED_PERFORMANCE_THRESHOLD_2 temperature
+ * to iwl_legacy_tt_handler() to get out of IWL_CT_KILL state
+ */
+void iwl_tt_exit_ct_kill(struct iwl_priv *priv)
+{
+ struct iwl_tt_mgmt *tt = &priv->power_data.tt;
+
+ if (test_bit(STATUS_EXIT_PENDING, &priv->status))
+ return;
+
+ /* stop ct_kill_exit_tm timer */
+ del_timer_sync(&priv->power_data.ct_kill_exit_tm);
+
+ if (tt->state == IWL_TI_CT_KILL) {
+ IWL_ERR(priv,
+ "Device temperature below critical"
+ "- ucode awake!\n");
+ iwl_legacy_tt_handler(priv,
+ IWL_REDUCED_PERFORMANCE_THRESHOLD_2);
+ }
+}
+EXPORT_SYMBOL(iwl_tt_exit_ct_kill);
+
+void iwl_tt_handler(struct iwl_priv *priv)
+{
+ s32 temp = priv->temperature; /* degrees CELSIUS except 4965 */
+
+ if (test_bit(STATUS_EXIT_PENDING, &priv->status))
+ return;
+
+ if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) == CSR_HW_REV_TYPE_4965)
+ temp = KELVIN_TO_CELSIUS(priv->temperature);
+
+ iwl_legacy_tt_handler(priv, temp);
+}
+EXPORT_SYMBOL(iwl_tt_handler);
+
+/* Thermal throttling initialization
+ */
+void iwl_tt_initialize(struct iwl_priv *priv)
+{
+ struct iwl_tt_mgmt *tt = &priv->power_data.tt;
+ struct iwl_power_mgr *setting = &priv->power_data;
+
+ IWL_DEBUG_POWER(priv, "Initialize Thermal Throttling \n");
+
+ memset(tt, 0, sizeof(struct iwl_tt_mgmt));
+
+ tt->state = IWL_TI_0;
+ tt->sys_power_mode = setting->power_mode;
+ tt->tt_power_mode = tt->sys_power_mode;
+ init_timer(&priv->power_data.ct_kill_exit_tm);
+ priv->power_data.ct_kill_exit_tm.data = (unsigned long)priv;
+ priv->power_data.ct_kill_exit_tm.function = iwl_tt_check_exit_ct_kill;
+}
+EXPORT_SYMBOL(iwl_tt_initialize);
+
+/* cleanup thermal throttling management related memory and timer */
+void iwl_tt_exit(struct iwl_priv *priv)
+{
+ /* stop ct_kill_exit_tm timer if activated */
+ del_timer_sync(&priv->power_data.ct_kill_exit_tm);
+}
+EXPORT_SYMBOL(iwl_tt_exit);
+
/* initialize to default */
void iwl_power_initialize(struct iwl_priv *priv)
{
diff --git a/drivers/net/wireless/iwlwifi/iwl-power.h b/drivers/net/wireless/iwlwifi/iwl-power.h
index 37ba3bb..7bb10d4 100644
--- a/drivers/net/wireless/iwlwifi/iwl-power.h
+++ b/drivers/net/wireless/iwlwifi/iwl-power.h
@@ -33,6 +33,38 @@

struct iwl_priv;

+#define IWL_TT_INCREASE_MARGIN 5
+
+/* Thermal Throttling State Machine states */
+enum iwl_tt_state {
+ IWL_TI_0, /* normal temperature, system power state */
+ IWL_TI_1, /* high temperature detect, low power state */
+ IWL_TI_2, /* higher temperature detected, lower power state */
+ IWL_TI_CT_KILL, /* critical temperature detected, lowest power state */
+ IWL_TI_STATE_MAX
+};
+
+/**
+ * struct iwl_tt_mgnt - Thermal Throttling Management structure
+ * @state: current Thermal Throttling state
+ * @tt_power_mode: Thermal Throttling power mode index
+ * being used to set power level when
+ * when thermal throttling state != IWL_TI_0
+ * the tt_power_mode should set to different
+ * power mode based on the current tt state
+ * @sys_power_mode: previous system power mode
+ * before transition into TT state
+ * @tt_previous_temperature: last measured temperature
+ */
+struct iwl_tt_mgmt {
+ enum iwl_tt_state state;
+ u8 tt_power_mode;
+ u8 sys_power_mode;
+#ifdef CONFIG_IWLWIFI_DEBUG
+ s32 tt_previous_temp;
+#endif
+};
+
enum {
IWL_POWER_MODE_CAM, /* Continuously Aware Mode, always on */
IWL_POWER_INDEX_1,
@@ -59,10 +91,20 @@ struct iwl_power_mgr {
u8 power_mode;
u8 user_power_setting; /* set by user through sysfs */
u8 power_disabled; /* set by mac80211's CONF_PS */
+ struct iwl_tt_mgmt tt; /* Thermal Throttling Management */
+ bool ct_kill_toggle; /* use to toggle the CSR bit when
+ * checking uCode temperature
+ */
+ struct timer_list ct_kill_exit_tm;
};

int iwl_power_update_mode(struct iwl_priv *priv, bool force);
int iwl_power_set_user_mode(struct iwl_priv *priv, u16 mode);
+void iwl_tt_enter_ct_kill(struct iwl_priv *priv);
+void iwl_tt_exit_ct_kill(struct iwl_priv *priv);
+void iwl_tt_handler(struct iwl_priv *priv);
+void iwl_tt_initialize(struct iwl_priv *priv);
+void iwl_tt_exit(struct iwl_priv *priv);
void iwl_power_initialize(struct iwl_priv *priv);

#endif /* __iwl_power_setting_h__ */
--
1.5.6.3