iwlwifi: sta: set max HE max A-MPDU according to HE capa

Currently, our max tpt is limited to max HT A-MPDU for LB,
and max VHT A-MPDU for HB. Configure HE exponent value correctly to
achieve HE max A-MPDU, both on LB and HB.
Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/iwlwifi.20201107104557.4486852ebb56.I9eb0d028e31f183597fb90120e7d4ca87e0dd6cb@changeid

drivers/net/wireless/intel/iwlwifi/fw/api/sta.h

@@ -5,10 +5,9 @@
  *
  * GPL LICENSE SUMMARY
  *
- * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2014 Intel Mobile Communications GmbH
  * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
- * Copyright(c) 2018 - 2019 Intel Corporation
+ * Copyright(c) 2012-2014, 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
@@ -28,10 +27,9 @@
  *
  * BSD LICENSE
  *
- * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2014 Intel Mobile Communications GmbH
  * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
- * Copyright(c) 2018 - 2019 Intel Corporation
+ * Copyright(c) 2012-2014, 2018 - 2020 Intel Corporation
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -128,7 +126,9 @@ enum iwl_sta_flags {
 	STA_FLG_MAX_AGG_SIZE_256K	= (5 << STA_FLG_MAX_AGG_SIZE_SHIFT),
 	STA_FLG_MAX_AGG_SIZE_512K	= (6 << STA_FLG_MAX_AGG_SIZE_SHIFT),
 	STA_FLG_MAX_AGG_SIZE_1024K	= (7 << STA_FLG_MAX_AGG_SIZE_SHIFT),
-	STA_FLG_MAX_AGG_SIZE_MSK	= (7 << STA_FLG_MAX_AGG_SIZE_SHIFT),
+	STA_FLG_MAX_AGG_SIZE_2M		= (8 << STA_FLG_MAX_AGG_SIZE_SHIFT),
+	STA_FLG_MAX_AGG_SIZE_4M		= (9 << STA_FLG_MAX_AGG_SIZE_SHIFT),
+	STA_FLG_MAX_AGG_SIZE_MSK	= (0xf << STA_FLG_MAX_AGG_SIZE_SHIFT),
 
 	STA_FLG_AGG_MPDU_DENS_SHIFT	= 23,
 	STA_FLG_AGG_MPDU_DENS_2US	= (4 << STA_FLG_AGG_MPDU_DENS_SHIFT),

drivers/net/wireless/intel/iwlwifi/mvm/sta.c

@@ -196,6 +196,7 @@ int iwl_mvm_sta_send_to_fw(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
 		mpdu_dens = sta->ht_cap.ampdu_density;
 	}
 
+
 	if (sta->vht_cap.vht_supported) {
 		agg_size = sta->vht_cap.cap &
 			IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK;
@@ -205,6 +206,23 @@ int iwl_mvm_sta_send_to_fw(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
 		agg_size = sta->ht_cap.ampdu_factor;
 	}
 
+	/* D6.0 10.12.2 A-MPDU length limit rules
+	 * A STA indicates the maximum length of the A-MPDU preEOF padding
+	 * that it can receive in an HE PPDU in the Maximum A-MPDU Length
+	 * Exponent field in its HT Capabilities, VHT Capabilities,
+	 * and HE 6 GHz Band Capabilities elements (if present) and the
+	 * Maximum AMPDU Length Exponent Extension field in its HE
+	 * Capabilities element
+	 */
+	if (sta->he_cap.has_he)
+		agg_size += u8_get_bits(sta->he_cap.he_cap_elem.mac_cap_info[3],
+					IEEE80211_HE_MAC_CAP3_MAX_AMPDU_LEN_EXP_MASK);
+
+	/* Limit to max A-MPDU supported by FW */
+	if (agg_size > (STA_FLG_MAX_AGG_SIZE_4M >> STA_FLG_MAX_AGG_SIZE_SHIFT))
+		agg_size = (STA_FLG_MAX_AGG_SIZE_4M >>
+			    STA_FLG_MAX_AGG_SIZE_SHIFT);
+
 	add_sta_cmd.station_flags |=
 		cpu_to_le32(agg_size << STA_FLG_MAX_AGG_SIZE_SHIFT);
 	add_sta_cmd.station_flags |=