From 58f2cc57dc6ac89946757b812fc5b93157978c37 Mon Sep 17 00:00:00 2001 From: Liad Kaufman Date: Wed, 30 Sep 2015 16:44:28 +0200 Subject: [PATCH] iwlwifi: mvm: support dqa-mode scd queue redirection Make sure that in DQA mode, the SCD's configuration of a queue is redirected to the lower AC of the streams of the queue. Make sure that this queue is redirected to the lowest AC when adding a new RA/TID to an existing queue. If it isn't - redirect the queue. Also, as redirection revealed a bug in the marking of a shared queue, this patch contains a small fix to make sure a shared queue maintains the appropriate "shared queue marking". Signed-off-by: Liad Kaufman Signed-off-by: Luca Coelho --- drivers/net/wireless/intel/iwlwifi/mvm/sta.c | 115 ++++++++++++++++++- 1 file changed, 110 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c index 1617de7c2ddc..a6d6df9529d0 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c @@ -513,6 +513,101 @@ static int iwl_mvm_get_shared_queue(struct iwl_mvm *mvm, return queue; } +/* + * If a given queue has a higher AC than the TID stream that is being added to + * it, the queue needs to be redirected to the lower AC. This function does that + * in such a case, otherwise - if no redirection required - it does nothing, + * unless the %force param is true. + */ +static int iwl_mvm_scd_queue_redirect(struct iwl_mvm *mvm, int queue, int tid, + int ac, int ssn, unsigned int wdg_timeout, + bool force) +{ + struct iwl_scd_txq_cfg_cmd cmd = { + .scd_queue = queue, + .enable = 0, + }; + bool shared_queue; + unsigned long mq; + int ret; + + /* + * If the AC is lower than current one - FIFO needs to be redirected to + * the lowest one of the streams in the queue. Check if this is needed + * here. + * Notice that the enum ieee80211_ac_numbers is "flipped", so BK is with + * value 3 and VO with value 0, so to check if ac X is lower than ac Y + * we need to check if the numerical value of X is LARGER than of Y. + */ + spin_lock_bh(&mvm->queue_info_lock); + if (ac <= mvm->queue_info[queue].mac80211_ac && !force) { + spin_unlock_bh(&mvm->queue_info_lock); + + IWL_DEBUG_TX_QUEUES(mvm, + "No redirection needed on TXQ #%d\n", + queue); + return 0; + } + + cmd.sta_id = mvm->queue_info[queue].ra_sta_id; + cmd.tx_fifo = iwl_mvm_ac_to_tx_fifo[mvm->queue_info[queue].mac80211_ac]; + mq = mvm->queue_info[queue].hw_queue_to_mac80211; + shared_queue = (mvm->queue_info[queue].hw_queue_refcount > 1); + spin_unlock_bh(&mvm->queue_info_lock); + + IWL_DEBUG_TX_QUEUES(mvm, "Redirecting shared TXQ #%d to FIFO #%d\n", + queue, iwl_mvm_ac_to_tx_fifo[ac]); + + /* Stop MAC queues and wait for this queue to empty */ + iwl_mvm_stop_mac_queues(mvm, mq); + ret = iwl_trans_wait_tx_queue_empty(mvm->trans, BIT(queue)); + if (ret) { + IWL_ERR(mvm, "Error draining queue %d before reconfig\n", + queue); + ret = -EIO; + goto out; + } + + /* Before redirecting the queue we need to de-activate it */ + iwl_trans_txq_disable(mvm->trans, queue, false); + ret = iwl_mvm_send_cmd_pdu(mvm, SCD_QUEUE_CFG, 0, sizeof(cmd), &cmd); + if (ret) + IWL_ERR(mvm, "Failed SCD disable TXQ %d (ret=%d)\n", queue, + ret); + + /* Make sure the SCD wrptr is correctly set before reconfiguring */ + iwl_trans_txq_enable(mvm->trans, queue, iwl_mvm_ac_to_tx_fifo[ac], + cmd.sta_id, tid, LINK_QUAL_AGG_FRAME_LIMIT_DEF, + ssn, wdg_timeout); + + /* TODO: Work-around SCD bug when moving back by multiples of 0x40 */ + + /* Redirect to lower AC */ + iwl_mvm_reconfig_scd(mvm, queue, iwl_mvm_ac_to_tx_fifo[ac], + cmd.sta_id, tid, LINK_QUAL_AGG_FRAME_LIMIT_DEF, + ssn); + + /* Update AC marking of the queue */ + spin_lock_bh(&mvm->queue_info_lock); + mvm->queue_info[queue].mac80211_ac = ac; + spin_unlock_bh(&mvm->queue_info_lock); + + /* + * Mark queue as shared in transport if shared + * Note this has to be done after queue enablement because enablement + * can also set this value, and there is no indication there to shared + * queues + */ + if (shared_queue) + iwl_trans_txq_set_shared_mode(mvm->trans, queue, true); + +out: + /* Continue using the MAC queues */ + iwl_mvm_start_mac_queues(mvm, mq); + + return ret; +} + static int iwl_mvm_sta_alloc_queue(struct iwl_mvm *mvm, struct ieee80211_sta *sta, u8 ac, int tid, struct ieee80211_hdr *hdr) @@ -680,17 +775,21 @@ static int iwl_mvm_sta_alloc_queue(struct iwl_mvm *mvm, iwl_mvm_invalidate_sta_queue(mvm, queue, disable_agg_tids, false); } - - /* Mark queue as shared in transport */ - iwl_trans_txq_set_shared_mode(mvm->trans, queue, true); - - /* TODO: a redirection may be required - DQA phase 2 */ } ssn = IEEE80211_SEQ_TO_SN(le16_to_cpu(hdr->seq_ctrl)); iwl_mvm_enable_txq(mvm, queue, mac_queue, ssn, &cfg, wdg_timeout); + /* + * Mark queue as shared in transport if shared + * Note this has to be done after queue enablement because enablement + * can also set this value, and there is no indication there to shared + * queues + */ + if (shared_queue) + iwl_trans_txq_set_shared_mode(mvm->trans, queue, true); + spin_lock_bh(&mvmsta->lock); mvmsta->tid_data[tid].txq_id = queue; mvmsta->tid_data[tid].is_tid_active = true; @@ -712,6 +811,12 @@ static int iwl_mvm_sta_alloc_queue(struct iwl_mvm *mvm, if (ret) goto out_err; } + } else { + /* Redirect queue, if needed */ + ret = iwl_mvm_scd_queue_redirect(mvm, queue, tid, ac, ssn, + wdg_timeout, false); + if (ret) + goto out_err; } return 0; -- 2.20.1