package/kernel/mac80211/patches/359-mac80211-minstrel-Enable-STBC-and-LDPC-for-VHT-Rates.patch

   1 From: Chaitanya T K <chaitanya.mgit@gmail.com>
   2 Date: Mon, 27 Jun 2016 15:23:26 +0530
   3 Subject: [PATCH] mac80211: minstrel: Enable STBC and LDPC for VHT Rates
   4
   5 If peer support reception of STBC and LDPC, enable them for better
   6 performance.
   7
   8 Signed-off-by: Chaitanya TK <chaitanya.mgit@gmail.com>
   9 ---
  10
  11 --- a/include/linux/ieee80211.h
  12 +++ b/include/linux/ieee80211.h
  13 @@ -1556,6 +1556,7 @@ struct ieee80211_vht_operation {
  14  #define IEEE80211_VHT_CAP_RXSTBC_3                             0x00000300
  15  #define IEEE80211_VHT_CAP_RXSTBC_4                             0x00000400
  16  #define IEEE80211_VHT_CAP_RXSTBC_MASK                          0x00000700
  17 +#define IEEE80211_VHT_CAP_RXSTBC_SHIFT                         8
  18  #define IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE                        0x00000800
  19  #define IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE                        0x00001000
  20  #define IEEE80211_VHT_CAP_BEAMFORMEE_STS_SHIFT                  13
  21 --- a/net/mac80211/rc80211_minstrel_ht.c
  22 +++ b/net/mac80211/rc80211_minstrel_ht.c
  23 @@ -1130,7 +1130,7 @@ minstrel_ht_update_caps(void *priv, stru
  24         struct minstrel_ht_sta_priv *msp = priv_sta;
  25         struct minstrel_ht_sta *mi = &msp->ht;
  26         struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
  27 -       u16 sta_cap = sta->ht_cap.cap;
  28 +       u16 ht_cap = sta->ht_cap.cap;
  29         struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
  30         struct sta_info *sinfo = container_of(sta, struct sta_info, sta);
  31         int use_vht;
  32 @@ -1138,6 +1138,7 @@ minstrel_ht_update_caps(void *priv, stru
  33         int ack_dur;
  34         int stbc;
  35         int i;
  36 +       bool ldpc = false;
  37
  38         /* fall back to the old minstrel for legacy stations */
  39         if (!sta->ht_cap.ht_supported)
  40 @@ -1175,16 +1176,24 @@ minstrel_ht_update_caps(void *priv, stru
  41         }
  42         mi->sample_tries = 4;
  43
  44 -       /* TODO tx_flags for vht - ATM the RC API is not fine-grained enough */
  45         if (!use_vht) {
  46 -               stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
  47 +               stbc = (ht_cap & IEEE80211_HT_CAP_RX_STBC) >>
  48                         IEEE80211_HT_CAP_RX_STBC_SHIFT;
  49 -               mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
  50
  51 -               if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
  52 -                       mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
  53 +               if (ht_cap & IEEE80211_HT_CAP_LDPC_CODING)
  54 +                       ldpc = true;
  55 +       } else {
  56 +               stbc = (vht_cap->cap & IEEE80211_VHT_CAP_RXSTBC_MASK) >>
  57 +                       IEEE80211_VHT_CAP_RXSTBC_SHIFT;
  58 +
  59 +               if (vht_cap->cap & IEEE80211_VHT_CAP_RXLDPC)
  60 +                       ldpc = true;
  61         }
  62
  63 +       mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
  64 +       if (ldpc)
  65 +               mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
  66 +
  67         for (i = 0; i < ARRAY_SIZE(mi->groups); i++) {
  68                 u32 gflags = minstrel_mcs_groups[i].flags;
  69                 int bw, nss;
  70 @@ -1197,10 +1206,10 @@ minstrel_ht_update_caps(void *priv, stru
  71
  72                 if (gflags & IEEE80211_TX_RC_SHORT_GI) {
  73                         if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
  74 -                               if (!(sta_cap & IEEE80211_HT_CAP_SGI_40))
  75 +                               if (!(ht_cap & IEEE80211_HT_CAP_SGI_40))
  76                                         continue;
  77                         } else {
  78 -                               if (!(sta_cap & IEEE80211_HT_CAP_SGI_20))
  79 +                               if (!(ht_cap & IEEE80211_HT_CAP_SGI_20))
  80                                         continue;
  81                         }
  82                 }