iwlwifi: pcie: write to legacy register also in MQ
authorSara Sharon <sara.sharon@intel.com>
Wed, 16 Mar 2016 14:28:42 +0000 (16:28 +0200)
committerEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Wed, 30 Mar 2016 13:21:25 +0000 (16:21 +0300)
Due to hardware bug, upon any shadow free-queue register write
access, a legacy RBD shadow register must be written as well.
This is required in order to trigger a copy of the shadow registers
values after MAC exits sleep state.
Specifically, the driver has to write (any value) to the legacy RBD
register each time FRBDCB is accessed.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
drivers/net/wireless/intel/iwlwifi/pcie/rx.c

index e379dbab685a1e8e55b21b78f5d1e626f6f1ad0d..59a7e45b12df1a986e800d507966cba947084e71 100644 (file)
@@ -210,8 +210,12 @@ static void iwl_pcie_rxq_inc_wr_ptr(struct iwl_trans *trans,
        if (trans->cfg->mq_rx_supported)
                iwl_write_prph(trans, RFH_Q_FRBDCB_WIDX(rxq->id),
                               rxq->write_actual);
-       else
-               iwl_write32(trans, FH_RSCSR_CHNL0_WPTR, rxq->write_actual);
+       /*
+        * write to FH_RSCSR_CHNL0_WPTR register even in MQ as a W/A to
+        * hardware shadow registers bug - writing to RFH_Q_FRBDCB_WIDX will
+        * not wake the NIC.
+        */
+       iwl_write32(trans, FH_RSCSR_CHNL0_WPTR, rxq->write_actual);
 }
 
 static void iwl_pcie_rxq_check_wrptr(struct iwl_trans *trans)