[PATCH 02/11] iwlwifi: mvm: attempt to allocate smaller queues

[Luca Coelho <luca@coelho.fi>]

From: Johannes Berg <johannes.berg@intel.com>

We currently attempt to allocate queues that are 512 entries long,
but that requires 32 KiB memory, which may not be available, at
least not contiguously. If we fail to allocate, attempt to use a
smaller queue all the way down to 16 entries (which fit into a
single page).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
---
 drivers/net/wireless/intel/iwlwifi/mvm/sta.c | 23 +++++++++++++-------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 1a210292f56c..3e16bd4190ff 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -744,16 +744,23 @@ static int iwl_mvm_tvqm_enable_txq(struct iwl_mvm *mvm,
 		size = max_t(u32, IWL_MGMT_QUEUE_SIZE,
 			     mvm->trans->cfg->min_txq_size);
 	}
-	queue = iwl_trans_txq_alloc(mvm->trans,
-				    cpu_to_le16(TX_QUEUE_CFG_ENABLE_QUEUE),
-				    sta_id, tid, SCD_QUEUE_CFG, size, timeout);
 
-	if (queue < 0) {
-		IWL_DEBUG_TX_QUEUES(mvm,
-				    "Failed allocating TXQ for sta %d tid %d, ret: %d\n",
-				    sta_id, tid, queue);
+	do {
+		__le16 enable = cpu_to_le16(TX_QUEUE_CFG_ENABLE_QUEUE);
+
+		queue = iwl_trans_txq_alloc(mvm->trans, enable,
+					    sta_id, tid, SCD_QUEUE_CFG,
+					    size, timeout);
+
+		if (queue < 0)
+			IWL_DEBUG_TX_QUEUES(mvm,
+					    "Failed allocating TXQ of size %d for sta %d tid %d, ret: %d\n",
+					    size, sta_id, tid, queue);
+		size /= 2;
+	} while (queue < 0 && size >= 16);
+
+	if (queue < 0)
 		return queue;
-	}
 
 	IWL_DEBUG_TX_QUEUES(mvm, "Enabling TXQ #%d for sta %d tid %d\n",
 			    queue, sta_id, tid);
-- 
2.26.2