iwlwifi: pcie: write to legacy register also in MQ

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>

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
index e379dba..59a7e45 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
@@ -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)