Re: [RFC] ath9k: Fix ath9k prevents CPU to enter C3 states

[Mohammed Shafi <mshajakhan@atheros.com>]

On Wednesday 16 February 2011 10:35 AM, Mohammed Shafi wrote:
> On Tuesday 15 February 2011 09:42 PM, John W. Linville wrote:
>> Despite the [RFC], I am applying this.  I should have reverted all
>> of this three weeks ago...
John can you please push this to stable kernel ?
> Thanks John.
>> John
>>
>> On Tue, Feb 15, 2011 at 09:29:32PM +0530, Mohammed Shafi Shajakhan 
>> wrote:
>>> From: Mohammed Shafi Shajakhan<mshajakhan@atheros.com>
>>>
>>> The DMA latency issue is observed only in Intel pinetrail platforms but
>>> in the driver we had a default PM-QOS value of 55. This caused
>>> unnecessary power consumption and battery drain in other platforms.
>>>     Remove the pm-qos thing in the driver code and address the 
>>> throughput issue in
>>> Intel pinetrail platfroms in user space using any one of the scripts 
>>> in below links:
>>> http://www.kernel.org/pub/linux/kernel/people/mcgrof/scripts/cpudmalatency.c 
>>>
>>> http://johannes.sipsolutions.net/files/netlatency.c.txt
>>> More details can be found in the following bugzilla link:
>>> https://bugzilla.kernel.org/show_bug.cgi?id=27532
>>>
>>> Signed-off-by: Mohammed Shafi Shajakhan<mshajakhan@atheros.com>
>>> ---
>>>   drivers/net/wireless/ath/ath9k/ath9k.h |    5 -----
>>>   drivers/net/wireless/ath/ath9k/init.c  |    7 -------
>>>   drivers/net/wireless/ath/ath9k/main.c  |    8 --------
>>>   3 files changed, 0 insertions(+), 20 deletions(-)
>>>
>>> diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h 
>>> b/drivers/net/wireless/ath/ath9k/ath9k.h
>>> index ba436cd..0052f64 100644
>>> --- a/drivers/net/wireless/ath/ath9k/ath9k.h
>>> +++ b/drivers/net/wireless/ath/ath9k/ath9k.h
>>> @@ -21,7 +21,6 @@
>>>   #include<linux/device.h>
>>>   #include<linux/leds.h>
>>>   #include<linux/completion.h>
>>> -#include<linux/pm_qos_params.h>
>>>
>>>   #include "debug.h"
>>>   #include "common.h"
>>> @@ -57,8 +56,6 @@ struct ath_node;
>>>
>>>   #define A_MAX(a, b) ((a)>  (b) ? (a) : (b))
>>>
>>> -#define ATH9K_PM_QOS_DEFAULT_VALUE    55
>>> -
>>>   #define TSF_TO_TU(_h,_l) \
>>>       ((((u32)(_h))<<  22) | (((u32)(_l))>>  10))
>>>
>>> @@ -650,7 +647,6 @@ struct ath_softc {
>>>
>>>       struct ath_ant_comb ant_comb;
>>>
>>> -    struct pm_qos_request_list pm_qos_req;
>>>   };
>>>
>>>   void ath9k_tasklet(unsigned long data);
>>> @@ -665,7 +661,6 @@ static inline void ath_read_cachesize(struct 
>>> ath_common *common, int *csz)
>>>   extern struct ieee80211_ops ath9k_ops;
>>>   extern int ath9k_modparam_nohwcrypt;
>>>   extern int led_blink;
>>> -extern int ath9k_pm_qos_value;
>>>   extern bool is_ath9k_unloaded;
>>>
>>>   irqreturn_t ath_isr(int irq, void *dev);
>>> diff --git a/drivers/net/wireless/ath/ath9k/init.c 
>>> b/drivers/net/wireless/ath/ath9k/init.c
>>> index e5c1eea..8fed4e4 100644
>>> --- a/drivers/net/wireless/ath/ath9k/init.c
>>> +++ b/drivers/net/wireless/ath/ath9k/init.c
>>> @@ -41,9 +41,6 @@ static int ath9k_btcoex_enable;
>>>   module_param_named(btcoex_enable, ath9k_btcoex_enable, int, 0444);
>>>   MODULE_PARM_DESC(btcoex_enable, "Enable wifi-BT coexistence");
>>>
>>> -int ath9k_pm_qos_value = ATH9K_PM_QOS_DEFAULT_VALUE;
>>> -module_param_named(pmqos, ath9k_pm_qos_value, int, S_IRUSR | 
>>> S_IRGRP | S_IROTH);
>>> -MODULE_PARM_DESC(pmqos, "User specified PM-QOS value");
>>>
>>>   bool is_ath9k_unloaded;
>>>   /* We use the hw_value as an index into our private channel 
>>> structure */
>>> @@ -760,9 +757,6 @@ int ath9k_init_device(u16 devid, struct 
>>> ath_softc *sc, u16 subsysid,
>>>       ath_init_leds(sc);
>>>       ath_start_rfkill_poll(sc);
>>>
>>> -    pm_qos_add_request(&sc->pm_qos_req, PM_QOS_CPU_DMA_LATENCY,
>>> -               PM_QOS_DEFAULT_VALUE);
>>> -
>>>       return 0;
>>>
>>>   error_world:
>>> @@ -819,7 +813,6 @@ void ath9k_deinit_device(struct ath_softc *sc)
>>>       ath9k_ps_restore(sc);
>>>
>>>       ieee80211_unregister_hw(hw);
>>> -    pm_qos_remove_request(&sc->pm_qos_req);
>>>       ath_rx_cleanup(sc);
>>>       ath_tx_cleanup(sc);
>>>       ath9k_deinit_softc(sc);
>>> diff --git a/drivers/net/wireless/ath/ath9k/main.c 
>>> b/drivers/net/wireless/ath/ath9k/main.c
>>> index 4f568b8..1d2c7c3 100644
>>> --- a/drivers/net/wireless/ath/ath9k/main.c
>>> +++ b/drivers/net/wireless/ath/ath9k/main.c
>>> @@ -1117,12 +1117,6 @@ static int ath9k_start(struct ieee80211_hw *hw)
>>>               ath9k_btcoex_timer_resume(sc);
>>>       }
>>>
>>> -    /* User has the option to provide pm-qos value as a module
>>> -     * parameter rather than using the default value of
>>> -     * 'ATH9K_PM_QOS_DEFAULT_VALUE'.
>>> -     */
>>> -    pm_qos_update_request(&sc->pm_qos_req, ath9k_pm_qos_value);
>>> -
>>>       if (ah->caps.pcie_lcr_extsync_en&&  
>>> common->bus_ops->extn_synch_en)
>>>           common->bus_ops->extn_synch_en(common);
>>>
>>> @@ -1267,8 +1261,6 @@ static void ath9k_stop(struct ieee80211_hw *hw)
>>>
>>>       sc->sc_flags |= SC_OP_INVALID;
>>>
>>> -    pm_qos_update_request(&sc->pm_qos_req, PM_QOS_DEFAULT_VALUE);
>>> -
>>>       mutex_unlock(&sc->mutex);
>>>
>>>       ath_dbg(common, ATH_DBG_CONFIG, "Driver halt\n");
>>> -- 
>>> 1.7.0.4
>>>
>>>