iwlwifi: pcie: retake ownership after reset

In most cases, unless shutting down the NIC, we really need
to retake ownership after doing a software reset of the NIC.
Encode that into the API so we "automatically" do it, even
in case of workarounds, and don't keep forgetting it like a
few of the places we have did.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20211204174545.458f9d98ac21.I40b9a22df1ab8178cc838fc83d5190e689dfac6a@changeid
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/dump.c b/drivers/net/wireless/intel/iwlwifi/fw/dump.c
index 016b3a4..358fc2d 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/fw/dump.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/dump.c
@@ -212,7 +212,9 @@ static void iwl_fwrt_dump_lmac_error_log(struct iwl_fw_runtime *fwrt, u8 lmac_nu
                IWL_ERR(trans, "HW error, resetting before reading\n");
 
                /* reset the device */
-               iwl_trans_sw_reset(trans);
+               err = iwl_trans_sw_reset(trans, true);
+               if (err)
+                       return;
 
                err = iwl_finish_nic_init(trans);
                if (err)

diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-trans.h b/drivers/net/wireless/intel/iwlwifi/iwl-trans.h
index 947ed82..9dea8f9 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/iwl-trans.h
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-trans.h
@@ -593,7 +593,7 @@ struct iwl_trans_ops {
        void (*configure)(struct iwl_trans *trans,
                          const struct iwl_trans_config *trans_cfg);
        void (*set_pmi)(struct iwl_trans *trans, bool state);
-       void (*sw_reset)(struct iwl_trans *trans);
+       int (*sw_reset)(struct iwl_trans *trans, bool retake_ownership);
        bool (*grab_nic_access)(struct iwl_trans *trans);
        void (*release_nic_access)(struct iwl_trans *trans);
        void (*set_bits_mask)(struct iwl_trans *trans, u32 reg, u32 mask,
@@ -1386,10 +1386,12 @@ static inline void iwl_trans_set_pmi(struct iwl_trans *trans, bool state)
                trans->ops->set_pmi(trans, state);
 }
 
-static inline void iwl_trans_sw_reset(struct iwl_trans *trans)
+static inline int iwl_trans_sw_reset(struct iwl_trans *trans,
+                                    bool retake_ownership)
 {
        if (trans->ops->sw_reset)
-               trans->ops->sw_reset(trans);
+               return trans->ops->sw_reset(trans, retake_ownership);
+       return 0;
 }
 
 static inline void

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans-gen2.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans-gen2.c
index 645cb4d..72b5b69 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/pcie/trans-gen2.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans-gen2.c
@@ -81,7 +81,7 @@ static void iwl_pcie_gen2_apm_stop(struct iwl_trans *trans, bool op_mode_leave)
        /* Stop device's DMA activity */
        iwl_pcie_apm_stop_master(trans);
 
-       iwl_trans_sw_reset(trans);
+       iwl_trans_sw_reset(trans, false);
 
        /*
         * Clear "initialization complete" bit to move adapter from
@@ -166,7 +166,8 @@ void _iwl_trans_pcie_gen2_stop_device(struct iwl_trans *trans)
        /* Stop the device, and put it in low power state */
        iwl_pcie_gen2_apm_stop(trans, false);
 
-       iwl_trans_sw_reset(trans);
+       /* re-take ownership to prevent other users from stealing the device */
+       iwl_trans_sw_reset(trans, true);
 
        /*
         * Upon stop, the IVAR table gets erased, so msi-x won't
@@ -196,9 +197,6 @@ void _iwl_trans_pcie_gen2_stop_device(struct iwl_trans *trans)
         * interrupt
         */
        iwl_enable_rfkill_int(trans);
-
-       /* re-take ownership to prevent other users from stealing the device */
-       iwl_pcie_prepare_card_hw(trans);
 }
 
 void iwl_trans_pcie_gen2_stop_device(struct iwl_trans *trans)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
index 0aeab8a..a63386a 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
@@ -127,7 +127,8 @@ out:
        kfree(buf);
 }
 
-static void iwl_trans_pcie_sw_reset(struct iwl_trans *trans)
+static int iwl_trans_pcie_sw_reset(struct iwl_trans *trans,
+                                  bool retake_ownership)
 {
        /* Reset entire device - do controller reset (results in SHRD_HW_RST) */
        if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_BZ)
@@ -137,6 +138,11 @@ static void iwl_trans_pcie_sw_reset(struct iwl_trans *trans)
                iwl_set_bit(trans, CSR_RESET,
                            CSR_RESET_REG_FLAG_SW_RESET);
        usleep_range(5000, 6000);
+
+       if (retake_ownership)
+               return iwl_pcie_prepare_card_hw(trans);
+
+       return 0;
 }
 
 static void iwl_pcie_free_fw_monitor(struct iwl_trans *trans)
@@ -382,9 +388,11 @@ static void iwl_pcie_apm_lp_xtal_enable(struct iwl_trans *trans)
        __iwl_trans_pcie_set_bit(trans, CSR_GP_CNTRL,
                                 CSR_GP_CNTRL_REG_FLAG_XTAL_ON);
 
-       iwl_trans_pcie_sw_reset(trans);
+       ret = iwl_trans_pcie_sw_reset(trans, true);
+
+       if (!ret)
+               ret = iwl_finish_nic_init(trans);
 
-       ret = iwl_finish_nic_init(trans);
        if (WARN_ON(ret)) {
                /* Release XTAL ON request */
                __iwl_trans_pcie_clear_bit(trans, CSR_GP_CNTRL,
@@ -409,7 +417,10 @@ static void iwl_pcie_apm_lp_xtal_enable(struct iwl_trans *trans)
                                 apmg_xtal_cfg_reg |
                                 SHR_APMG_XTAL_CFG_XTAL_ON_REQ);
 
-       iwl_trans_pcie_sw_reset(trans);
+       ret = iwl_trans_pcie_sw_reset(trans, true);
+       if (ret)
+               IWL_ERR(trans,
+                       "iwl_pcie_apm_lp_xtal_enable: failed to retake NIC ownership\n");
 
        /* Enable LP XTAL by indirect access through CSR */
        apmg_gp1_reg = iwl_trans_pcie_read_shr(trans, SHR_APMG_GP1_REG);
@@ -515,7 +526,7 @@ static void iwl_pcie_apm_stop(struct iwl_trans *trans, bool op_mode_leave)
                return;
        }
 
-       iwl_trans_pcie_sw_reset(trans);
+       iwl_trans_pcie_sw_reset(trans, false);
 
        /*
         * Clear "initialization complete" bit to move adapter from
@@ -1261,7 +1272,8 @@ static void _iwl_trans_pcie_stop_device(struct iwl_trans *trans)
        /* Stop the device, and put it in low power state */
        iwl_pcie_apm_stop(trans, false);
 
-       iwl_trans_pcie_sw_reset(trans);
+       /* re-take ownership to prevent other users from stealing the device */
+       iwl_trans_pcie_sw_reset(trans, true);
 
        /*
         * Upon stop, the IVAR table gets erased, so msi-x won't
@@ -1291,9 +1303,6 @@ static void _iwl_trans_pcie_stop_device(struct iwl_trans *trans)
         * interrupt
         */
        iwl_enable_rfkill_int(trans);
-
-       /* re-take ownership to prevent other users from stealing the device */
-       iwl_pcie_prepare_card_hw(trans);
 }
 
 void iwl_pcie_synchronize_irqs(struct iwl_trans *trans)
@@ -1802,9 +1811,7 @@ static int iwl_pcie_gen2_force_power_gating(struct iwl_trans *trans)
        iwl_clear_bits_prph(trans, HPM_HIPM_GEN_CFG,
                            HPM_HIPM_GEN_CFG_CR_FORCE_ACTIVE);
 
-       iwl_trans_pcie_sw_reset(trans);
-
-       return 0;
+       return iwl_trans_pcie_sw_reset(trans, true);
 }
 
 static int _iwl_trans_pcie_start_hw(struct iwl_trans *trans)
@@ -1824,7 +1831,9 @@ static int _iwl_trans_pcie_start_hw(struct iwl_trans *trans)
        if (err)
                return err;
 
-       iwl_trans_pcie_sw_reset(trans);
+       err = iwl_trans_pcie_sw_reset(trans, true);
+       if (err)
+               return err;
 
        if (trans->trans_cfg->device_family == IWL_DEVICE_FAMILY_22000 &&
            trans->trans_cfg->integrated) {