Return-path: Received: from mail-oa0-f43.google.com ([209.85.219.43]:33466 "EHLO mail-oa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756764AbaBFUit (ORCPT ); Thu, 6 Feb 2014 15:38:49 -0500 Message-ID: <52F3F2D7.4020102@lwfinger.net> (sfid-20140206_213915_895094_0EDD1DFF) Date: Thu, 06 Feb 2014 14:38:47 -0600 From: Larry Finger MIME-Version: 1.0 To: Olivier Langlois , linville@tuxdriver.com, chaoming_li@realsil.com.cn CC: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Stable Subject: Re: [PATCH 1/2] rtlwifi: rtl8192ce: Fix too long disable of IRQs References: <1391235070-23180-1-git-send-email-olivier@trillion01.com> In-Reply-To: <1391235070-23180-1-git-send-email-olivier@trillion01.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 02/01/2014 12:11 AM, Olivier Langlois wrote: > rtl8192ce is disabling for too long the local interrupts during hw initiatialisation when performing scans > > The observable symptoms in dmesg can be: > > - underruns from ALSA playback > - clock freezes (tstamps do not change for several dmesg entries until irqs are finaly reenabled): > > [ 250.817669] rtlwifi:rtl_op_config():<0-0-0> 0x100 > [ 250.817685] rtl8192ce:_rtl92ce_phy_set_rf_power_state():<0-1-0> IPS Set eRf nic enable > [ 250.817732] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.817796] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.817910] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818024] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818139] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818253] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818367] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818472] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818472] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818472] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818472] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:18051d59:11 > [ 250.818472] rtl8192ce:_rtl92ce_init_mac():<0-1-0> reg0xec:98053f15:10 > [ 250.818472] rtl8192ce:rtl92ce_sw_led_on():<0-1-0> LedAddr:4E ledpin=1 > [ 250.818472] rtl8192c_common:rtl92c_download_fw():<0-1-0> Firmware Version(49), Signature(0x88c1),Size(32) > [ 250.818472] rtl8192ce:rtl92ce_enable_hw_security_config():<0-1-0> PairwiseEncAlgorithm = 0 GroupEncAlgorithm = 0 > [ 250.818472] rtl8192ce:rtl92ce_enable_hw_security_config():<0-1-0> The SECR-value cc > [ 250.818472] rtl8192c_common:rtl92c_dm_check_txpower_tracking_thermal_meter():<0-1-0> Schedule TxPowerTracking direct call!! > [ 250.818472] rtl8192c_common:rtl92c_dm_txpower_tracking_callback_thermalmeter():<0-1-0> rtl92c_dm_txpower_tracking_callback_thermalmeter > [ 250.818472] rtl8192c_common:rtl92c_dm_txpower_tracking_callback_thermalmeter():<0-1-0> Readback Thermal Meter = 0xe pre thermal meter 0xf eeprom_thermalmeter 0xf > [ 250.818472] rtl8192c_common:rtl92c_dm_txpower_tracking_callback_thermalmeter():<0-1-0> Initial pathA ele_d reg0xc80 = 0x40000000, ofdm_index=0xc > [ 250.818472] rtl8192c_common:rtl92c_dm_txpower_tracking_callback_thermalmeter():<0-1-0> Initial reg0xa24 = 0x90e1317, cck_index=0xc, ch14 0 > [ 250.818472] rtl8192c_common:rtl92c_dm_txpower_tracking_callback_thermalmeter():<0-1-0> Readback Thermal Meter = 0xe pre thermal meter 0xf eeprom_thermalmeter 0xf delta 0x1 delta_lck 0x0 delta_iqk 0x0 > [ 250.818472] rtl8192c_common:rtl92c_dm_txpower_tracking_callback_thermalmeter():<0-1-0> <=== > [ 250.818472] rtl8192c_common:rtl92c_dm_initialize_txpower_tracking_thermalmeter():<0-1-0> pMgntInfo->txpower_tracking = 1 > [ 250.818472] rtl8192ce:rtl92ce_led_control():<0-1-0> ledaction 3 > [ 250.818472] rtl8192ce:rtl92ce_sw_led_on():<0-1-0> LedAddr:4E ledpin=1 > [ 250.818472] rtlwifi:rtl_ips_nic_on():<0-1-0> before spin_unlock_irqrestore > [ 251.154656] PCM: Lost interrupts? [Q]-0 (stream=0, delta=15903, new_hw_ptr=293408, old_hw_ptr=277505) > > The exact code flow that causes that is: > > 1. wpa_supplicant send a start_scan request to the nl80211 driver > 2. mac80211 module call rtl_op_config with IEEE80211_CONF_CHANGE_IDLE > 3. rtl_ips_nic_on is called which disable local irqs > 4. rtl92c_phy_set_rf_power_state() is called > 5. rtl_ps_enable_nic() is called and hw_init()is executed and then the interrupts on the device are enabled > > A good solution could be to refactor the code to avoid calling rtl92ce_hw_init() with the irqs disabled > but a quick and dirty solution that has proven to work is > to reenable the irqs during the function rtl92ce_hw_init(). > > I think that it is safe doing so since the device interrupt will only be enabled after the init function succeed. > > Signed-off-by: Olivier Langlois > Cc: Stable Acked-by: Larry Finger Larry > --- > drivers/net/wireless/rtlwifi/rtl8192ce/hw.c | 18 ++++++++++++++++-- > 1 file changed, 16 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/wireless/rtlwifi/rtl8192ce/hw.c b/drivers/net/wireless/rtlwifi/rtl8192ce/hw.c > index a82b30a..2eb0b38 100644 > --- a/drivers/net/wireless/rtlwifi/rtl8192ce/hw.c > +++ b/drivers/net/wireless/rtlwifi/rtl8192ce/hw.c > @@ -937,14 +937,26 @@ int rtl92ce_hw_init(struct ieee80211_hw *hw) > bool is92c; > int err; > u8 tmp_u1b; > + unsigned long flags; > > rtlpci->being_init_adapter = true; > + > + /* Since this function can take a very long time (up to 350 ms) > + * and can be called with irqs disabled, reenable the irqs > + * to let the other devices continue being serviced. > + * > + * It is safe doing so since our own interrupts will only be enabled > + * in a subsequent step. > + */ > + local_save_flags(flags); > + local_irq_enable(); > + > rtlpriv->intf_ops->disable_aspm(hw); > rtstatus = _rtl92ce_init_mac(hw); > if (!rtstatus) { > RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG, "Init MAC failed\n"); > err = 1; > - return err; > + goto exit; > } > > err = rtl92c_download_fw(hw); > @@ -952,7 +964,7 @@ int rtl92ce_hw_init(struct ieee80211_hw *hw) > RT_TRACE(rtlpriv, COMP_ERR, DBG_WARNING, > "Failed to download FW. Init HW without FW now..\n"); > err = 1; > - return err; > + goto exit; > } > > rtlhal->last_hmeboxnum = 0; > @@ -1032,6 +1044,8 @@ int rtl92ce_hw_init(struct ieee80211_hw *hw) > RT_TRACE(rtlpriv, COMP_INIT, DBG_TRACE, "under 1.5V\n"); > } > rtl92c_dm_init(hw); > +exit: > + local_irq_restore(flags); > rtlpci->being_init_adapter = false; > return err; > } >