Commit 752d95a2 authored by Johannes Berg's avatar Johannes Berg Committed by Luca Coelho
Browse files

iwlwifi: pcie: allocate much smaller byte-count table 



The hardware needs a byte-count table with the size of each frame
on the queue to build A-MPDUs, but:
 * newer generation no longer have the duplicated space at the end,
   they can deal with the wrap properly - and we don't even fill
   the dup anyway
 * we have a maximum queue size of 512 right now and don't use the
   theoretical hardware maximum of 65536.

Together, this reduces the byte count table DMA allocation from
64KiB (65536*2 + 64*2 rounded up) to 1 KiB (though that might be
rounded up to a full 4 KiB page by the allocator, not sure it can
share the allocations.)

Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarLuca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200425130140.c263b787b5ab.I059507a9760b1ce1d45d84dcaa91629a5cfb58e0@changeid
parent 36dfe9ac

drivers/net/wireless/intel/iwlwifi/iwl-fh.h

+3 −4
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 
 *

 * Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved.

 * Copyright(c) 2015 - 2017 Intel Deutschland GmbH

 * Copyright(c) 2018 - 2019 Intel Corporation

 * Copyright(c) 2018 - 2020 Intel Corporation

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of version 2 of the GNU General Public License as
@@ -29,7 +29,7 @@ 
 *

 * Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved.

 * Copyright(c) 2015 - 2017 Intel Deutschland GmbH

 * Copyright(c) 2018 - 2019 Intel Corporation

 * Copyright(c) 2018 - 2020 Intel Corporation

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without
@@ -646,8 +646,7 @@ struct iwl_rb_status { 
#define TFD_QUEUE_CB_SIZE(x)	(ilog2(x) - 3)

#define TFD_QUEUE_SIZE_BC_DUP	(64)

#define TFD_QUEUE_BC_SIZE	(TFD_QUEUE_SIZE_MAX + TFD_QUEUE_SIZE_BC_DUP)

#define TFD_QUEUE_BC_SIZE_GEN3	(TFD_QUEUE_SIZE_MAX_GEN3 + \

				 TFD_QUEUE_SIZE_BC_DUP)

#define TFD_QUEUE_BC_SIZE_GEN3	512

#define IWL_TX_DMA_MASK        DMA_BIT_MASK(36)

#define IWL_NUM_OF_TBS		20

#define IWL_TFH_NUM_TBS		25

drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c

+16 −8
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ 
 * GPL LICENSE SUMMARY

 *

 * Copyright(c) 2017 Intel Deutschland GmbH

 * Copyright(c) 2018 - 2019 Intel Corporation

 * Copyright(c) 2018 - 2020 Intel Corporation

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of version 2 of the GNU General Public License as
@@ -20,7 +20,7 @@ 
 * BSD LICENSE

 *

 * Copyright(c) 2017 Intel Deutschland GmbH

 * Copyright(c) 2018 - 2019 Intel Corporation

 * Copyright(c) 2018 - 2020 Intel Corporation

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without
@@ -1272,17 +1272,25 @@ int iwl_trans_pcie_dyn_txq_alloc_dma(struct iwl_trans *trans, 
				     struct iwl_txq **intxq, int size,

				     unsigned int timeout)

{

	size_t bc_tbl_size, bc_tbl_entries;

	struct iwl_txq *txq;

	int ret;



	struct iwl_txq *txq;

	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210) {

		bc_tbl_size = sizeof(struct iwl_gen3_bc_tbl);

		bc_tbl_entries = bc_tbl_size / sizeof(u16);

	} else {

		bc_tbl_size = sizeof(struct iwlagn_scd_bc_tbl);

		bc_tbl_entries = bc_tbl_size / sizeof(u16);

	}



	if (WARN_ON(size > bc_tbl_entries))

		return -EINVAL;



	txq = kzalloc(sizeof(*txq), GFP_KERNEL);

	if (!txq)

		return -ENOMEM;

	ret = iwl_pcie_alloc_dma_ptr(trans, &txq->bc_tbl,

				     (trans->trans_cfg->device_family >=

				      IWL_DEVICE_FAMILY_AX210) ?

				     sizeof(struct iwl_gen3_bc_tbl) :

				     sizeof(struct iwlagn_scd_bc_tbl));

	ret = iwl_pcie_alloc_dma_ptr(trans, &txq->bc_tbl, bc_tbl_size);

	if (ret) {

		IWL_ERR(trans, "Scheduler BC Table allocation failed\n");

		kfree(txq);

CRA Git | Maintained and supported by SUSTech CRA and CCSE