mac80211: minstrel_ht: add basic support for VHT rates <= 3SS@80MHz
When the new CONFIG_MAC80211_RC_MINSTREL_VHT is not set (default 'N'),
there is no behavioral change including in sampling and MCS_GROUP_RATES
remains 8.
Otherwise MCS_GROUP_RATES is 10, and a module parameter *vht_only*
(default 'true'), restricts the rates selection to VHT when VHT is
supported.
Regarding the debugfs stats buffer:
It is explicitly increased from 8k to 32k to fit every rates incl. when
both HT and VHT rates are enabled, as for the format, before:
type rate tpt eprob *prob ret *ok(*cum) ok( cum)
HT20/LGI ABCDP MCS0 0.0 0.0 0.0 1 0( 0) 0( 0)
after:
type rate tpt eprob *prob ret *ok(*cum) ok( cum)
HT20/LGI ABCDP MCS0 0.0 0.0 0.0 1 0( 0) 0( 0)
VHT40/LGI MCS5/2 0.0 0.0 0.0 0 0( 0) 0( 0)
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index e760d3d..4666681 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -10,6 +10,7 @@
#include <linux/skbuff.h>
#include <linux/debugfs.h>
#include <linux/random.h>
+#include <linux/moduleparam.h>
#include <linux/ieee80211.h>
#include <net/mac80211.h>
#include "rate.h"
@@ -36,6 +37,7 @@
#define BW_20 0
#define BW_40 1
+#define BW_80 2
/*
* Define group sort order: HT40 -> SGI -> #streams
@@ -66,6 +68,47 @@
} \
}
+#define VHT_GROUP_IDX(_streams, _sgi, _bw) \
+ (MINSTREL_VHT_GROUP_0 + \
+ MINSTREL_MAX_STREAMS * 2 * (_bw) + \
+ MINSTREL_MAX_STREAMS * (_sgi) + \
+ (_streams) - 1)
+
+#define BW2VBPS(_bw, r3, r2, r1) \
+ (_bw == BW_80 ? r3 : _bw == BW_40 ? r2 : r1)
+
+#define VHT_GROUP(_streams, _sgi, _bw) \
+ [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \
+ .streams = _streams, \
+ .flags = \
+ IEEE80211_TX_RC_VHT_MCS | \
+ (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \
+ (_bw == BW_80 ? IEEE80211_TX_RC_80_MHZ_WIDTH : \
+ _bw == BW_40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \
+ .duration = { \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 117, 54, 26)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 234, 108, 52)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 351, 162, 78)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 468, 216, 104)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 702, 324, 156)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 936, 432, 208)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1053, 486, 234)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1170, 540, 260)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1404, 648, 312)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1560, 720, 346)) \
+ } \
+}
+
#define CCK_DURATION(_bitrate, _short, _len) \
(1000 * (10 /* SIFS */ + \
(_short ? 72 + 24 : 144 + 48) + \
@@ -91,6 +134,13 @@
} \
}
+#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
+static bool minstrel_vht_only = true;
+module_param(minstrel_vht_only, bool, 0644);
+MODULE_PARM_DESC(minstrel_vht_only,
+ "Use only VHT rates when VHT is supported by sta.");
+#endif
+
/*
* To enable sufficiently targeted rate sampling, MCS rates are divided into
* groups, based on the number of streams and flags (HT40, SGI) that they
@@ -124,9 +174,46 @@
MCS_GROUP(3, 1, BW_40),
#endif
- CCK_GROUP
-};
+ CCK_GROUP,
+#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
+ VHT_GROUP(1, 0, BW_20),
+ VHT_GROUP(2, 0, BW_20),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_20),
+#endif
+
+ VHT_GROUP(1, 1, BW_20),
+ VHT_GROUP(2, 1, BW_20),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_20),
+#endif
+
+ VHT_GROUP(1, 0, BW_40),
+ VHT_GROUP(2, 0, BW_40),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_40),
+#endif
+
+ VHT_GROUP(1, 1, BW_40),
+ VHT_GROUP(2, 1, BW_40),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_40),
+#endif
+
+ VHT_GROUP(1, 0, BW_80),
+ VHT_GROUP(2, 0, BW_80),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_80),
+#endif
+
+ VHT_GROUP(1, 1, BW_80),
+ VHT_GROUP(2, 1, BW_80),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_80),
+#endif
+#endif
+};
static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly;
@@ -134,6 +221,45 @@
minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi);
/*
+ * Some VHT MCSes are invalid (when Ndbps / Nes is not an integer)
+ * e.g for MCS9@20MHzx1Nss: Ndbps=8x52*(5/6) Nes=1
+ *
+ * Returns the valid mcs map for struct minstrel_mcs_group_data.supported
+ */
+static u16
+minstrel_get_valid_vht_rates(int bw, int nss, __le16 mcs_map)
+{
+ u16 mask = 0;
+
+ if (bw == BW_20) {
+ if (nss != 3 && nss != 6)
+ mask = BIT(9);
+ } else if (bw == BW_80) {
+ if (nss == 3 || nss == 7)
+ mask = BIT(6);
+ else if (nss == 6)
+ mask = BIT(9);
+ } else {
+ WARN_ON(bw != BW_40);
+ }
+
+ switch ((le16_to_cpu(mcs_map) >> (2 * (nss - 1))) & 3) {
+ case IEEE80211_VHT_MCS_SUPPORT_0_7:
+ mask |= 0x300;
+ break;
+ case IEEE80211_VHT_MCS_SUPPORT_0_8:
+ mask |= 0x200;
+ break;
+ case IEEE80211_VHT_MCS_SUPPORT_0_9:
+ break;
+ default:
+ mask = 0x3ff;
+ }
+
+ return 0x3ff & ~mask;
+}
+
+/*
* Look up an MCS group index based on mac80211 rate information
*/
static int
@@ -144,6 +270,15 @@
!!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH));
}
+static int
+minstrel_vht_get_group_idx(struct ieee80211_tx_rate *rate)
+{
+ return VHT_GROUP_IDX(ieee80211_rate_get_vht_nss(rate),
+ !!(rate->flags & IEEE80211_TX_RC_SHORT_GI),
+ !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) +
+ 2*!!(rate->flags & IEEE80211_TX_RC_80_MHZ_WIDTH));
+}
+
static struct minstrel_rate_stats *
minstrel_ht_get_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
struct ieee80211_tx_rate *rate)
@@ -153,6 +288,9 @@
if (rate->flags & IEEE80211_TX_RC_MCS) {
group = minstrel_ht_get_group_idx(rate);
idx = rate->idx % 8;
+ } else if (rate->flags & IEEE80211_TX_RC_VHT_MCS) {
+ group = minstrel_vht_get_group_idx(rate);
+ idx = ieee80211_rate_get_vht_mcs(rate);
} else {
group = MINSTREL_CCK_GROUP;
@@ -489,7 +627,8 @@
if (!rate->count)
return false;
- if (rate->flags & IEEE80211_TX_RC_MCS)
+ if (rate->flags & IEEE80211_TX_RC_MCS ||
+ rate->flags & IEEE80211_TX_RC_VHT_MCS)
return true;
return rate->idx == mp->cck_rates[0] ||
@@ -736,6 +875,9 @@
if (index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP)
idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)];
+ else if (flags & IEEE80211_TX_RC_VHT_MCS)
+ idx = ((group->streams - 1) << 4) |
+ ((index % MCS_GROUP_RATES) & 0xF);
else
idx = index % MCS_GROUP_RATES + (group->streams - 1) * 8;
@@ -917,6 +1059,9 @@
if (sample_idx / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) {
int idx = sample_idx % ARRAY_SIZE(mp->cck_rates);
rate->idx = mp->cck_rates[idx];
+ } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) {
+ ieee80211_rate_set_vht(rate, sample_idx % MCS_GROUP_RATES,
+ sample_group->streams);
} else {
rate->idx = sample_idx % MCS_GROUP_RATES +
(sample_group->streams - 1) * 8;
@@ -962,6 +1107,8 @@
struct minstrel_ht_sta *mi = &msp->ht;
struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
u16 sta_cap = sta->ht_cap.cap;
+ struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
+ int use_vht;
int n_supported = 0;
int ack_dur;
int stbc;
@@ -973,6 +1120,13 @@
BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB);
+#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
+ if (vht_cap->vht_supported)
+ use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0);
+ else
+#endif
+ use_vht = 0;
+
msp->is_ht = true;
memset(mi, 0, sizeof(*mi));
@@ -996,15 +1150,19 @@
}
mi->sample_tries = 4;
- stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
- IEEE80211_HT_CAP_RX_STBC_SHIFT;
- mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
+ /* TODO tx_flags for vht - ATM the RC API is not fine-grained enough */
+ if (!use_vht) {
+ stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
+ IEEE80211_HT_CAP_RX_STBC_SHIFT;
+ mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
- if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
- mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
+ if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
+ mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
+ }
for (i = 0; i < ARRAY_SIZE(mi->groups); i++) {
u32 gflags = minstrel_mcs_groups[i].flags;
+ int bw, nss;
mi->groups[i].supported = 0;
if (i == MINSTREL_CCK_GROUP) {
@@ -1026,13 +1184,47 @@
sta->bandwidth < IEEE80211_STA_RX_BW_40)
continue;
+ nss = minstrel_mcs_groups[i].streams;
+
/* Mark MCS > 7 as unsupported if STA is in static SMPS mode */
- if (sta->smps_mode == IEEE80211_SMPS_STATIC &&
- minstrel_mcs_groups[i].streams > 1)
+ if (sta->smps_mode == IEEE80211_SMPS_STATIC && nss > 1)
continue;
- mi->groups[i].supported =
- mcs->rx_mask[minstrel_mcs_groups[i].streams - 1];
+ /* HT rate */
+ if (gflags & IEEE80211_TX_RC_MCS) {
+#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
+ if (minstrel_vht_only)
+ continue;
+#endif
+ mi->groups[i].supported = mcs->rx_mask[nss - 1];
+ if (mi->groups[i].supported)
+ n_supported++;
+ continue;
+ }
+
+ /* VHT rate */
+ if (!vht_cap->vht_supported ||
+ WARN_ON(!(gflags & IEEE80211_TX_RC_VHT_MCS)) ||
+ WARN_ON(gflags & IEEE80211_TX_RC_160_MHZ_WIDTH))
+ continue;
+
+ if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) {
+ if (sta->bandwidth < IEEE80211_STA_RX_BW_80 ||
+ ((gflags & IEEE80211_TX_RC_SHORT_GI) &&
+ !(vht_cap->cap & IEEE80211_VHT_CAP_SHORT_GI_80))) {
+ continue;
+ }
+ }
+
+ if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH)
+ bw = BW_40;
+ else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH)
+ bw = BW_80;
+ else
+ bw = BW_20;
+
+ mi->groups[i].supported = minstrel_get_valid_vht_rates(bw, nss,
+ vht_cap->vht_mcs.tx_mcs_map);
if (mi->groups[i].supported)
n_supported++;