Return-path: Received: from paleale.coelho.fi ([176.9.41.70]:45564 "EHLO farmhouse.coelho.fi" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727207AbeHaNEB (ORCPT ); Fri, 31 Aug 2018 09:04:01 -0400 From: Luca Coelho To: johannes@sipsolutions.net Cc: linux-wireless@vger.kernel.org, Johannes Berg Date: Fri, 31 Aug 2018 11:31:16 +0300 Message-Id: <20180831083130.15525-15-luca@coelho.fi> (sfid-20180831_105820_009688_DD86DE0E) In-Reply-To: <20180831083130.15525-1-luca@coelho.fi> References: <20180831083130.15525-1-luca@coelho.fi> Subject: [PATCH 14/28] ieee80211: add new VHT capability fields/parsing Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Johannes Berg IEEE 802.11-2016 extended the VHT capability fields to allow indicating the number of spatial streams depending on the actually used bandwidth, add support for decoding this. Signed-off-by: Johannes Berg --- include/linux/ieee80211.h | 35 +++++++++++- net/wireless/util.c | 109 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 142 insertions(+), 2 deletions(-) diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h index 0c9d6d0a9d47..13a73ff12cfa 100644 --- a/include/linux/ieee80211.h +++ b/include/linux/ieee80211.h @@ -1460,13 +1460,16 @@ struct ieee80211_ht_operation { * STA can receive. Rate expressed in units of 1 Mbps. * If this field is 0 this value should not be used to * consider the highest RX data rate supported. - * The top 3 bits of this field are reserved. + * The top 3 bits of this field indicate the Maximum NSTS,total + * (a beamformee capability.) * @tx_mcs_map: TX MCS map 2 bits for each stream, total 8 streams * @tx_highest: Indicates highest long GI VHT PPDU data rate * STA can transmit. Rate expressed in units of 1 Mbps. * If this field is 0 this value should not be used to * consider the highest TX data rate supported. - * The top 3 bits of this field are reserved. + * The top 2 bits of this field are reserved, the + * 3rd bit from the top indiciates VHT Extended NSS BW + * Capability. */ struct ieee80211_vht_mcs_info { __le16 rx_mcs_map; @@ -1475,6 +1478,13 @@ struct ieee80211_vht_mcs_info { __le16 tx_highest; } __packed; +/* for rx_highest */ +#define IEEE80211_VHT_MAX_NSTS_TOTAL_SHIFT 13 +#define IEEE80211_VHT_MAX_NSTS_TOTAL_MASK (7 << IEEE80211_VHT_MAX_NSTS_TOTAL_SHIFT) + +/* for tx_highest */ +#define IEEE80211_VHT_EXT_NSS_BW_CAPABLE (1 << 13) + /** * enum ieee80211_vht_mcs_support - VHT MCS support definitions * @IEEE80211_VHT_MCS_SUPPORT_0_7: MCSes 0-7 are supported for the @@ -1650,6 +1660,7 @@ struct ieee80211_mu_edca_param_set { #define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ 0x00000004 #define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ 0x00000008 #define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK 0x0000000C +#define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_SHIFT 2 #define IEEE80211_VHT_CAP_RXLDPC 0x00000010 #define IEEE80211_VHT_CAP_SHORT_GI_80 0x00000020 #define IEEE80211_VHT_CAP_SHORT_GI_160 0x00000040 @@ -1678,6 +1689,26 @@ struct ieee80211_mu_edca_param_set { #define IEEE80211_VHT_CAP_VHT_LINK_ADAPTATION_VHT_MRQ_MFB 0x0c000000 #define IEEE80211_VHT_CAP_RX_ANTENNA_PATTERN 0x10000000 #define IEEE80211_VHT_CAP_TX_ANTENNA_PATTERN 0x20000000 +#define IEEE80211_VHT_CAP_EXT_NSS_BW_SHIFT 30 +#define IEEE80211_VHT_CAP_EXT_NSS_BW_MASK 0xc0000000 + +/** + * ieee80211_get_vht_max_nss - return max NSS for a given bandwidth/MCS + * @cap: VHT capabilities of the peer + * @bw: bandwidth to use + * @mcs: MCS index to use + * @ext_nss_bw_capable: indicates whether or not the local transmitter + * (rate scaling algorithm) can deal with the new logic + * (dot11VHTExtendedNSSBWCapable) + * + * Due to the VHT Extended NSS Bandwidth Support, the maximum NSS can + * vary for a given BW/MCS. This function parses the data. + * + * Note: This function is exported by cfg80211. + */ +int ieee80211_get_vht_max_nss(struct ieee80211_vht_cap *cap, + enum ieee80211_vht_chanwidth bw, + int mcs, bool ext_nss_bw_capable); /* 802.11ax HE MAC capabilities */ #define IEEE80211_HE_MAC_CAP0_HTC_HE 0x01 diff --git a/net/wireless/util.c b/net/wireless/util.c index 2a89db5f2db7..97b4095ed4d8 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -5,17 +5,20 @@ * Copyright 2007-2009 Johannes Berg * Copyright 2013-2014 Intel Mobile Communications GmbH * Copyright 2017 Intel Deutschland GmbH + * Copyright (C) 2018 Intel Corporation */ #include #include #include #include +#include #include #include #include #include #include #include +#include #include "core.h" #include "rdev-ops.h" @@ -1938,3 +1941,109 @@ void cfg80211_send_layer2_update(struct net_device *dev, const u8 *addr) netif_rx_ni(skb); } EXPORT_SYMBOL(cfg80211_send_layer2_update); + +int ieee80211_get_vht_max_nss(struct ieee80211_vht_cap *cap, + enum ieee80211_vht_chanwidth bw, + int mcs, bool ext_nss_bw_capable) +{ + u16 map = le16_to_cpu(cap->supp_mcs.rx_mcs_map); + int max_vht_nss = 0; + int ext_nss_bw; + int supp_width; + int i, mcs_encoding; + + if (map == 0xffff) + return 0; + + if (WARN_ON(mcs > 9)) + return 0; + if (mcs <= 7) + mcs_encoding = 0; + else if (mcs == 8) + mcs_encoding = 1; + else + mcs_encoding = 2; + + /* find max_vht_nss for the given MCS */ + for (i = 7; i >= 0; i--) { + int supp = (map >> (2 * i)) & 3; + + if (supp == 3) + continue; + + if (supp >= mcs_encoding) { + max_vht_nss = i; + break; + } + } + + if (!(cap->supp_mcs.tx_mcs_map & + cpu_to_le16(IEEE80211_VHT_EXT_NSS_BW_CAPABLE))) + return max_vht_nss; + + ext_nss_bw = le32_get_bits(cap->vht_cap_info, + IEEE80211_VHT_CAP_EXT_NSS_BW_MASK); + supp_width = le32_get_bits(cap->vht_cap_info, + IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK); + + /* if not capable, treat ext_nss_bw as 0 */ + if (!ext_nss_bw_capable) + ext_nss_bw = 0; + + /* This is invalid */ + if (supp_width == 3) + return 0; + + /* This is an invalid combination so pretend nothing is supported */ + if (supp_width == 2 && (ext_nss_bw == 1 || ext_nss_bw == 2)) + return 0; + + /* + * Cover all the special cases according to IEEE 802.11-2016 + * Table 9-250. All other cases are either factor of 1 or not + * valid/supported. + */ + switch (bw) { + case IEEE80211_VHT_CHANWIDTH_USE_HT: + case IEEE80211_VHT_CHANWIDTH_80MHZ: + if ((supp_width == 1 || supp_width == 2) && + ext_nss_bw == 3) + return 2 * max_vht_nss; + break; + case IEEE80211_VHT_CHANWIDTH_160MHZ: + if (supp_width == 0 && + (ext_nss_bw == 1 || ext_nss_bw == 2)) + return DIV_ROUND_UP(max_vht_nss, 2); + if (supp_width == 0 && + ext_nss_bw == 3) + return DIV_ROUND_UP(3 * max_vht_nss, 4); + if (supp_width == 1 && + ext_nss_bw == 3) + return 2 * max_vht_nss; + break; + case IEEE80211_VHT_CHANWIDTH_80P80MHZ: + if (supp_width == 0 && + (ext_nss_bw == 1 || ext_nss_bw == 2)) + return 0; /* not possible */ + if (supp_width == 0 && + ext_nss_bw == 2) + return DIV_ROUND_UP(max_vht_nss, 2); + if (supp_width == 0 && + ext_nss_bw == 3) + return DIV_ROUND_UP(3 * max_vht_nss, 4); + if (supp_width == 1 && + ext_nss_bw == 0) + return 0; /* not possible */ + if (supp_width == 1 && + ext_nss_bw == 1) + return DIV_ROUND_UP(max_vht_nss, 2); + if (supp_width == 1 && + ext_nss_bw == 2) + return DIV_ROUND_UP(3 * max_vht_nss, 4); + break; + } + + /* not covered or invalid combination received */ + return max_vht_nss; +} +EXPORT_SYMBOL(ieee80211_get_vht_max_nss); -- 2.18.0