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-rw-r--r--drivers/net/wireless/iwlwifi/mvm/rs.c921
-rw-r--r--drivers/net/wireless/iwlwifi/mvm/rs.h64
2 files changed, 458 insertions, 527 deletions
diff --git a/drivers/net/wireless/iwlwifi/mvm/rs.c b/drivers/net/wireless/iwlwifi/mvm/rs.c
index 1bfdde5..1bb6581 100644
--- a/drivers/net/wireless/iwlwifi/mvm/rs.c
+++ b/drivers/net/wireless/iwlwifi/mvm/rs.c
@@ -123,6 +123,190 @@ static const struct iwl_rs_rate_info iwl_rates[IWL_RATE_COUNT] = {
IWL_DECLARE_MCS_RATE(9), /* MCS 9 */
};
+enum rs_column_mode {
+ RS_INVALID = 0,
+ RS_LEGACY,
+ RS_SISO,
+ RS_MIMO2,
+};
+
+#define MAX_NEXT_COLUMNS 5
+#define MAX_COLUMN_CHECKS 3
+
+typedef bool (*allow_column_func_t) (struct iwl_mvm *mvm,
+ struct ieee80211_sta *sta,
+ struct iwl_scale_tbl_info *tbl);
+
+struct rs_tx_column {
+ enum rs_column_mode mode;
+ u8 ant;
+ bool sgi;
+ enum rs_column next_columns[MAX_NEXT_COLUMNS];
+ allow_column_func_t checks[MAX_COLUMN_CHECKS];
+};
+
+static bool rs_mimo_allow(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
+ struct iwl_scale_tbl_info *tbl)
+{
+ if (!sta->ht_cap.ht_supported)
+ return false;
+
+ if (sta->smps_mode == IEEE80211_SMPS_STATIC)
+ return false;
+
+ if (num_of_ant(iwl_fw_valid_tx_ant(mvm->fw)) < 2)
+ return false;
+
+ if (!iwl_mvm_bt_coex_is_mimo_allowed(mvm, sta))
+ return false;
+
+ return true;
+}
+
+static bool rs_siso_allow(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
+ struct iwl_scale_tbl_info *tbl)
+{
+ if (!sta->ht_cap.ht_supported)
+ return false;
+
+ return true;
+}
+
+static bool rs_sgi_allow(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
+ struct iwl_scale_tbl_info *tbl)
+{
+ struct rs_rate *rate = &tbl->rate;
+ struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
+ struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
+
+ if (is_ht20(rate) && (ht_cap->cap &
+ IEEE80211_HT_CAP_SGI_20))
+ return true;
+ if (is_ht40(rate) && (ht_cap->cap &
+ IEEE80211_HT_CAP_SGI_40))
+ return true;
+ if (is_ht80(rate) && (vht_cap->cap &
+ IEEE80211_VHT_CAP_SHORT_GI_80))
+ return true;
+
+ return false;
+}
+
+static const struct rs_tx_column rs_tx_columns[] = {
+ [RS_COLUMN_LEGACY_ANT_A] = {
+ .mode = RS_LEGACY,
+ .ant = ANT_A,
+ .next_columns = {
+ RS_COLUMN_LEGACY_ANT_B,
+ RS_COLUMN_SISO_ANT_A,
+ RS_COLUMN_MIMO2,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ },
+ },
+ [RS_COLUMN_LEGACY_ANT_B] = {
+ .mode = RS_LEGACY,
+ .ant = ANT_B,
+ .next_columns = {
+ RS_COLUMN_LEGACY_ANT_A,
+ RS_COLUMN_SISO_ANT_B,
+ RS_COLUMN_MIMO2,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ },
+ },
+ [RS_COLUMN_SISO_ANT_A] = {
+ .mode = RS_SISO,
+ .ant = ANT_A,
+ .next_columns = {
+ RS_COLUMN_SISO_ANT_B,
+ RS_COLUMN_MIMO2,
+ RS_COLUMN_SISO_ANT_A_SGI,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ },
+ .checks = {
+ rs_siso_allow,
+ },
+ },
+ [RS_COLUMN_SISO_ANT_B] = {
+ .mode = RS_SISO,
+ .ant = ANT_B,
+ .next_columns = {
+ RS_COLUMN_SISO_ANT_A,
+ RS_COLUMN_MIMO2,
+ RS_COLUMN_SISO_ANT_B_SGI,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ },
+ .checks = {
+ rs_siso_allow,
+ },
+ },
+ [RS_COLUMN_SISO_ANT_A_SGI] = {
+ .mode = RS_SISO,
+ .ant = ANT_A,
+ .sgi = true,
+ .next_columns = {
+ RS_COLUMN_SISO_ANT_B_SGI,
+ RS_COLUMN_MIMO2_SGI,
+ RS_COLUMN_SISO_ANT_A,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ },
+ .checks = {
+ rs_siso_allow,
+ rs_sgi_allow,
+ },
+ },
+ [RS_COLUMN_SISO_ANT_B_SGI] = {
+ .mode = RS_SISO,
+ .ant = ANT_B,
+ .sgi = true,
+ .next_columns = {
+ RS_COLUMN_SISO_ANT_A_SGI,
+ RS_COLUMN_MIMO2_SGI,
+ RS_COLUMN_SISO_ANT_B,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ },
+ .checks = {
+ rs_siso_allow,
+ rs_sgi_allow,
+ },
+ },
+ [RS_COLUMN_MIMO2] = {
+ .mode = RS_MIMO2,
+ .ant = ANT_AB,
+ .next_columns = {
+ RS_COLUMN_SISO_ANT_A,
+ RS_COLUMN_MIMO2_SGI,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ },
+ .checks = {
+ rs_mimo_allow,
+ },
+ },
+ [RS_COLUMN_MIMO2_SGI] = {
+ .mode = RS_MIMO2,
+ .ant = ANT_AB,
+ .sgi = true,
+ .next_columns = {
+ RS_COLUMN_SISO_ANT_A_SGI,
+ RS_COLUMN_MIMO2,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ RS_COLUMN_INVALID,
+ },
+ .checks = {
+ rs_mimo_allow,
+ rs_sgi_allow,
+ },
+ },
+};
+
static inline u8 rs_extract_rate(u32 rate_n_flags)
{
/* also works for HT because bits 7:6 are zero there */
@@ -839,6 +1023,9 @@ static void rs_tx_status(void *mvm_r, struct ieee80211_supported_band *sband,
lq_sta->missed_rate_counter++;
if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
lq_sta->missed_rate_counter = 0;
+ IWL_DEBUG_RATE(mvm,
+ "Too many rates mismatch. Send sync LQ. rs_state %d\n",
+ lq_sta->rs_state);
iwl_mvm_send_lq_cmd(mvm, &lq_sta->lq, false);
}
/* Regardless, ignore this status info for outdated rate */
@@ -888,7 +1075,7 @@ static void rs_tx_status(void *mvm_r, struct ieee80211_supported_band *sband,
info->status.ampdu_ack_len);
/* Update success/fail counts if not searching for new mode */
- if (lq_sta->stay_in_tbl) {
+ if (lq_sta->rs_state == RS_STATE_STAY_IN_COLUMN) {
lq_sta->total_success += info->status.ampdu_ack_len;
lq_sta->total_failed += (info->status.ampdu_len -
info->status.ampdu_ack_len);
@@ -915,14 +1102,20 @@ static void rs_tx_status(void *mvm_r, struct ieee80211_supported_band *sband,
tmp_tbl = curr_tbl;
else if (rs_rate_match(&rate, &other_tbl->rate))
tmp_tbl = other_tbl;
- else
+ else {
+ IWL_DEBUG_RATE(mvm,
+ "Tx packet rate doesn't match ACTIVE or SEARCH tables\n");
+ rs_dump_rate(mvm, &rate, "Tx PACKET:");
+ rs_dump_rate(mvm, &curr_tbl->rate, "CURRENT:");
+ rs_dump_rate(mvm, &other_tbl->rate, "OTHER:");
continue;
+ }
rs_collect_tx_data(tmp_tbl, rate.index, 1,
i < retries ? 0 : legacy_success);
}
/* Update success/fail counts if not searching for new mode */
- if (lq_sta->stay_in_tbl) {
+ if (lq_sta->rs_state == RS_STATE_STAY_IN_COLUMN) {
lq_sta->total_success += legacy_success;
lq_sta->total_failed += retries + (1 - legacy_success);
}
@@ -946,8 +1139,8 @@ done:
static void rs_set_stay_in_table(struct iwl_mvm *mvm, u8 is_legacy,
struct iwl_lq_sta *lq_sta)
{
- IWL_DEBUG_RATE(mvm, "we are staying in the same table\n");
- lq_sta->stay_in_tbl = 1; /* only place this gets set */
+ IWL_DEBUG_RATE(mvm, "Moving to RS_STATE_STAY_IN_COLUMN\n");
+ lq_sta->rs_state = RS_STATE_STAY_IN_COLUMN;
if (is_legacy) {
lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
@@ -961,38 +1154,31 @@ static void rs_set_stay_in_table(struct iwl_mvm *mvm, u8 is_legacy,
lq_sta->total_failed = 0;
lq_sta->total_success = 0;
lq_sta->flush_timer = jiffies;
- lq_sta->action_counter = 0;
+ lq_sta->visited_columns = 0;
}
-/*
- * Find correct throughput table for given mode of modulation
- */
-static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
- struct iwl_scale_tbl_info *tbl)
+static s32 *rs_get_expected_tpt_table(struct iwl_lq_sta *lq_sta,
+ const struct rs_tx_column *column,
+ u32 bw)
{
/* Used to choose among HT tables */
s32 (*ht_tbl_pointer)[IWL_RATE_COUNT];
- struct rs_rate *rate = &tbl->rate;
- /* Check for invalid LQ type */
- if (WARN_ON_ONCE(!is_legacy(rate) && !is_ht(rate) &&
- !(is_vht(rate)))) {
- tbl->expected_tpt = expected_tpt_legacy;
- return;
- }
+ if (WARN_ON_ONCE(column->mode != RS_LEGACY &&
+ column->mode != RS_SISO &&
+ column->mode != RS_MIMO2))
+ return expected_tpt_legacy;
/* Legacy rates have only one table */
- if (is_legacy(rate)) {
- tbl->expected_tpt = expected_tpt_legacy;
- return;
- }
+ if (column->mode == RS_LEGACY)
+ return expected_tpt_legacy;
ht_tbl_pointer = expected_tpt_mimo2_20MHz;
/* Choose among many HT tables depending on number of streams
* (SISO/MIMO2), channel width (20/40/80), SGI, and aggregation
* status */
- if (is_siso(rate)) {
- switch (rate->bw) {
+ if (column->mode == RS_SISO) {
+ switch (bw) {
case RATE_MCS_CHAN_WIDTH_20:
ht_tbl_pointer = expected_tpt_siso_20MHz;
break;
@@ -1005,8 +1191,8 @@ static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
default:
WARN_ON_ONCE(1);
}
- } else if (is_mimo2(rate)) {
- switch (rate->bw) {
+ } else if (column->mode == RS_MIMO2) {
+ switch (bw) {
case RATE_MCS_CHAN_WIDTH_20:
ht_tbl_pointer = expected_tpt_mimo2_20MHz;
break;
@@ -1023,14 +1209,23 @@ static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
WARN_ON_ONCE(1);
}
- if (!rate->sgi && !lq_sta->is_agg) /* Normal */
- tbl->expected_tpt = ht_tbl_pointer[0];
- else if (rate->sgi && !lq_sta->is_agg) /* SGI */
- tbl->expected_tpt = ht_tbl_pointer[1];
- else if (!rate->sgi && lq_sta->is_agg) /* AGG */
- tbl->expected_tpt = ht_tbl_pointer[2];
+ if (!column->sgi && !lq_sta->is_agg) /* Normal */
+ return ht_tbl_pointer[0];
+ else if (column->sgi && !lq_sta->is_agg) /* SGI */
+ return ht_tbl_pointer[1];
+ else if (!column->sgi && lq_sta->is_agg) /* AGG */
+ return ht_tbl_pointer[2];
else /* AGG+SGI */
- tbl->expected_tpt = ht_tbl_pointer[3];
+ return ht_tbl_pointer[3];
+}
+
+static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
+ struct iwl_scale_tbl_info *tbl)
+{
+ struct rs_rate *rate = &tbl->rate;
+ const struct rs_tx_column *column = &rs_tx_columns[tbl->column];
+
+ tbl->expected_tpt = rs_get_expected_tpt_table(lq_sta, column, rate->bw);
}
/*
@@ -1135,19 +1330,6 @@ static s32 rs_get_best_rate(struct iwl_mvm *mvm,
return new_rate;
}
-/* Move to the next action and wrap around to the first action in case
- * we're at the last action. Assumes actions start at 0.
- */
-static inline void rs_move_next_action(struct iwl_scale_tbl_info *tbl,
- u8 last_action)
-{
- BUILD_BUG_ON(IWL_LEGACY_FIRST_ACTION != 0);
- BUILD_BUG_ON(IWL_SISO_FIRST_ACTION != 0);
- BUILD_BUG_ON(IWL_MIMO2_FIRST_ACTION != 0);
-
- tbl->action = (tbl->action + 1) % (last_action + 1);
-}
-
static u32 rs_bw_from_sta_bw(struct ieee80211_sta *sta)
{
if (sta->bandwidth >= IEEE80211_STA_RX_BW_80)
@@ -1158,409 +1340,6 @@ static u32 rs_bw_from_sta_bw(struct ieee80211_sta *sta)
return RATE_MCS_CHAN_WIDTH_20;
}
-static bool rs_sgi_allowed(struct rs_rate *rate,
- struct ieee80211_sta *sta)
-{
- struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
- struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
-
- if (is_ht20(rate) && (ht_cap->cap &
- IEEE80211_HT_CAP_SGI_20))
- return true;
- if (is_ht40(rate) && (ht_cap->cap &
- IEEE80211_HT_CAP_SGI_40))
- return true;
- if (is_ht80(rate) && (vht_cap->cap &
- IEEE80211_VHT_CAP_SHORT_GI_80))
- return true;
-
- return false;
-}
-
-/*
- * Set up search table for MIMO2
- */
-static int rs_switch_to_mimo2(struct iwl_mvm *mvm,
- struct iwl_lq_sta *lq_sta,
- struct ieee80211_sta *sta,
- struct iwl_scale_tbl_info *tbl, int index)
-{
- u16 rate_mask;
- s32 rate_idx;
-
- if (!sta->ht_cap.ht_supported)
- return -1;
-
- if (sta->smps_mode == IEEE80211_SMPS_STATIC)
- return -1;
-
- /* Need both Tx chains/antennas to support MIMO */
- if (num_of_ant(iwl_fw_valid_tx_ant(mvm->fw)) < 2)
- return -1;
-
- IWL_DEBUG_RATE(mvm, "LQ: try to switch to MIMO2\n");
-
- tbl->rate.type = lq_sta->is_vht ? LQ_VHT_MIMO2 : LQ_HT_MIMO2;
- tbl->action = 0;
- tbl->max_search = IWL_MAX_SEARCH;
- rate_mask = lq_sta->active_mimo2_rate;
-
- tbl->rate.bw = rs_bw_from_sta_bw(sta);
- rs_set_expected_tpt_table(lq_sta, tbl);
-
- rate_idx = rs_get_best_rate(mvm, lq_sta, tbl, rate_mask, index);
-
- IWL_DEBUG_RATE(mvm, "LQ: MIMO2 best rate %d mask %X\n",
- rate_idx, rate_mask);
- if ((rate_idx == IWL_RATE_INVALID) || !((1 << rate_idx) & rate_mask)) {
- IWL_DEBUG_RATE(mvm, "Can't switch with index %d rate mask %x\n",
- rate_idx, rate_mask);
- return -1;
- }
-
- tbl->rate.index = rate_idx;
- tbl->current_rate = ucode_rate_from_rs_rate(mvm, &tbl->rate);
-
- IWL_DEBUG_RATE(mvm, "LQ: Switch to new mcs %X index\n",
- tbl->current_rate);
- return 0;
-}
-
-/*
- * Set up search table for SISO
- */
-static int rs_switch_to_siso(struct iwl_mvm *mvm,
- struct iwl_lq_sta *lq_sta,
- struct ieee80211_sta *sta,
- struct iwl_scale_tbl_info *tbl, int index)
-{
- u16 rate_mask;
- s32 rate_idx;
-
- if (!sta->ht_cap.ht_supported)
- return -1;
-
- IWL_DEBUG_RATE(mvm, "LQ: try to switch to SISO\n");
-
- tbl->rate.type = lq_sta->is_vht ? LQ_VHT_SISO : LQ_HT_SISO;
- tbl->action = 0;
- tbl->max_search = IWL_MAX_SEARCH;
- rate_mask = lq_sta->active_siso_rate;
-
- tbl->rate.bw = rs_bw_from_sta_bw(sta);
- rs_set_expected_tpt_table(lq_sta, tbl);
- rate_idx = rs_get_best_rate(mvm, lq_sta, tbl, rate_mask, index);
-
- IWL_DEBUG_RATE(mvm, "LQ: get best rate %d mask %X\n",
- rate_idx, rate_mask);
- if ((rate_idx == IWL_RATE_INVALID) || !((1 << rate_idx) & rate_mask)) {
- IWL_DEBUG_RATE(mvm,
- "can not switch with index %d rate mask %x\n",
- rate_idx, rate_mask);
- return -1;
- }
-
- tbl->rate.index = rate_idx;
- tbl->current_rate = ucode_rate_from_rs_rate(mvm, &tbl->rate);
-
- IWL_DEBUG_RATE(mvm, "LQ: Switch to new mcs %X index\n",
- tbl->current_rate);
- return 0;
-}
-
-/*
- * Try to switch to new modulation mode from legacy
- */
-static int rs_move_legacy_other(struct iwl_mvm *mvm,
- struct iwl_lq_sta *lq_sta,
- struct ieee80211_sta *sta,
- int index)
-{
- struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
- struct iwl_scale_tbl_info *search_tbl =
- &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
- struct rs_rate *rate = &search_tbl->rate;
- struct iwl_rate_scale_data *window = &(tbl->win[index]);
- u32 sz = (sizeof(struct iwl_scale_tbl_info) -
- (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
- u8 start_action;
- u8 valid_tx_ant = iwl_fw_valid_tx_ant(mvm->fw);
- u8 tx_chains_num = num_of_ant(valid_tx_ant);
- int ret;
- u8 update_search_tbl_counter = 0;
-
- start_action = tbl->action;
- while (1) {
- lq_sta->action_counter++;
- switch (tbl->action) {
- case IWL_LEGACY_SWITCH_ANTENNA:
- IWL_DEBUG_RATE(mvm, "LQ: Legacy toggle Antenna\n");
-
- if (tx_chains_num <= 1)
- break;
-
- /* Don't change antenna if success has been great */
- if (window->success_ratio >= IWL_RS_GOOD_RATIO)
- break;
-
- /* Set up search table to try other antenna */
- memcpy(search_tbl, tbl, sz);
-
- if (rs_toggle_antenna(valid_tx_ant,
- &search_tbl->current_rate,
- &search_tbl->rate)) {
- update_search_tbl_counter = 1;
- rs_set_expected_tpt_table(lq_sta, search_tbl);
- goto out;
- }
- break;
- case IWL_LEGACY_SWITCH_SISO:
- IWL_DEBUG_RATE(mvm, "LQ: Legacy switch to SISO\n");
-
- /* Set up search table to try SISO */
- memcpy(search_tbl, tbl, sz);
- rate->sgi = false;
- ret = rs_switch_to_siso(mvm, lq_sta, sta,
- search_tbl, index);
- if (!ret) {
- lq_sta->action_counter = 0;
- goto out;
- }
-
- break;
- case IWL_LEGACY_SWITCH_MIMO2:
- IWL_DEBUG_RATE(mvm, "LQ: Legacy switch to MIMO2\n");
-
- /* Set up search table to try MIMO */
- memcpy(search_tbl, tbl, sz);
- rate->sgi = false;
- rate->ant = ANT_AB;
-
- if (!rs_is_valid_ant(valid_tx_ant,
- rate->ant))
- break;
-
- ret = rs_switch_to_mimo2(mvm, lq_sta, sta,
- search_tbl, index);
- if (!ret) {
- lq_sta->action_counter = 0;
- goto out;
- }
- break;
- default:
- WARN_ON_ONCE(1);
- }
- rs_move_next_action(tbl, IWL_LEGACY_LAST_ACTION);
-
- if (tbl->action == start_action)
- break;
- }
- rate->type = LQ_NONE;
- return 0;
-
-out:
- lq_sta->search_better_tbl = 1;
- rs_move_next_action(tbl, IWL_LEGACY_LAST_ACTION);
- if (update_search_tbl_counter)
- search_tbl->action = tbl->action;
- return 0;
-}
-
-/*
- * Try to switch to new modulation mode from SISO
- */
-static int rs_move_siso_to_other(struct iwl_mvm *mvm,
- struct iwl_lq_sta *lq_sta,
- struct ieee80211_sta *sta, int index)
-{
- struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
- struct iwl_scale_tbl_info *search_tbl =
- &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
- struct rs_rate *rate = &search_tbl->rate;
- struct iwl_rate_scale_data *window = &(tbl->win[index]);
- u32 sz = (sizeof(struct iwl_scale_tbl_info) -
- (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
- u8 start_action;
- u8 valid_tx_ant = iwl_fw_valid_tx_ant(mvm->fw);
- u8 tx_chains_num = num_of_ant(valid_tx_ant);
- u8 update_search_tbl_counter = 0;
- int ret;
-
- if (tbl->action == IWL_SISO_SWITCH_MIMO2 &&
- !iwl_mvm_bt_coex_is_mimo_allowed(mvm, sta))
- tbl->action = IWL_SISO_SWITCH_ANTENNA;
-
- start_action = tbl->action;
- while (1) {
- lq_sta->action_counter++;
- switch (tbl->action) {
- case IWL_SISO_SWITCH_ANTENNA:
- IWL_DEBUG_RATE(mvm, "LQ: SISO toggle Antenna\n");
- if (tx_chains_num <= 1)
- break;
-
- if (window->success_ratio >= IWL_RS_GOOD_RATIO &&
- BT_MBOX_MSG(&mvm->last_bt_notif, 3,
- TRAFFIC_LOAD) == 0)
- break;
-
- memcpy(search_tbl, tbl, sz);
- if (rs_toggle_antenna(valid_tx_ant,
- &search_tbl->current_rate,
- rate)) {
- update_search_tbl_counter = 1;
- goto out;
- }
- break;
- case IWL_SISO_SWITCH_MIMO2:
- IWL_DEBUG_RATE(mvm, "LQ: SISO switch to MIMO2\n");
- memcpy(search_tbl, tbl, sz);
- rate->sgi = false;
- rate->ant = ANT_AB;
-
- if (!rs_is_valid_ant(valid_tx_ant,
- rate->ant))
- break;
-
- ret = rs_switch_to_mimo2(mvm, lq_sta, sta,
- search_tbl, index);
- if (!ret)
- goto out;
- break;
- case IWL_SISO_SWITCH_GI:
- if (!rs_sgi_allowed(rate, sta))
- break;
-
- IWL_DEBUG_RATE(mvm, "LQ: SISO toggle SGI/NGI\n");
-
- memcpy(search_tbl, tbl, sz);
- rate->sgi = !tbl->rate.sgi;
- rs_set_expected_tpt_table(lq_sta, search_tbl);
- if (tbl->rate.sgi) {
- s32 tpt = lq_sta->last_tpt / 100;
- if (tpt >= search_tbl->expected_tpt[index])
- break;
- }
- rate->index = index;
- search_tbl->current_rate =
- ucode_rate_from_rs_rate(mvm, rate);
- update_search_tbl_counter = 1;
- goto out;
- default:
- WARN_ON_ONCE(1);
- }
- rs_move_next_action(tbl, IWL_SISO_LAST_ACTION);
-
- if (tbl->action == start_action)
- break;
- }
- rate->type = LQ_NONE;
- return 0;
-
- out:
- lq_sta->search_better_tbl = 1;
- rs_move_next_action(tbl, IWL_SISO_LAST_ACTION);
- if (update_search_tbl_counter)
- search_tbl->action = tbl->action;
-
- return 0;
-}
-
-/*
- * Try to switch to new modulation mode from MIMO2
- */
-static int rs_move_mimo2_to_other(struct iwl_mvm *mvm,
- struct iwl_lq_sta *lq_sta,
- struct ieee80211_sta *sta, int index)
-{
- struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
- struct iwl_scale_tbl_info *search_tbl =
- &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
- struct rs_rate *rate = &search_tbl->rate;
- u32 sz = (sizeof(struct iwl_scale_tbl_info) -
- (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
- u8 start_action;
- u8 valid_tx_ant = iwl_fw_valid_tx_ant(mvm->fw);
- u8 update_search_tbl_counter = 0;
- int ret;
-
- if (!iwl_mvm_bt_coex_is_mimo_allowed(mvm, sta)) {
- IWL_DEBUG_RATE(mvm, "BT COEX force switch to SISO A\n");
- tbl->action = IWL_MIMO2_SWITCH_SISO_A;
- }
-
- start_action = tbl->action;
- while (1) {
- lq_sta->action_counter++;
- switch (tbl->action) {
- case IWL_MIMO2_SWITCH_SISO_A:
- case IWL_MIMO2_SWITCH_SISO_B:
- IWL_DEBUG_RATE(mvm, "LQ: MIMO2 switch to SISO\n");
-
- /* Set up new search table for SISO */
- memcpy(search_tbl, tbl, sz);
-
- if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
- rate->ant = ANT_A;
- else /* tbl->action == IWL_MIMO2_SWITCH_SISO_B */
- rate->ant = ANT_B;
-
- if (!rs_is_valid_ant(valid_tx_ant,
- rate->ant))
- break;
-
- ret = rs_switch_to_siso(mvm, lq_sta, sta,
- search_tbl, index);
- if (!ret)
- goto out;
-
- break;
-
- case IWL_MIMO2_SWITCH_GI:
- if (!rs_sgi_allowed(rate, sta))
- break;
-
- IWL_DEBUG_RATE(mvm, "LQ: MIMO2 toggle SGI/NGI\n");
-
- /* Set up new search table for MIMO2 */
- memcpy(search_tbl, tbl, sz);
- rate->sgi = !tbl->rate.sgi;
- rs_set_expected_tpt_table(lq_sta, search_tbl);
- /*
- * If active table already uses the fastest possible
- * modulation (dual stream with short guard interval),
- * and it's working well, there's no need to look
- * for a better type of modulation!
- */
- if (tbl->rate.sgi) {
- s32 tpt = lq_sta->last_tpt / 100;
- if (tpt >= search_tbl->expected_tpt[index])
- break;
- }
- rate->index = index;
- search_tbl->current_rate =
- ucode_rate_from_rs_rate(mvm, rate);
- update_search_tbl_counter = 1;
- goto out;
- default:
- WARN_ON_ONCE(1);
- }
- rs_move_next_action(tbl, IWL_MIMO2_LAST_ACTION);
-
- if (tbl->action == start_action)
- break;
- }
- rate->type = LQ_NONE;
- return 0;
- out:
- lq_sta->search_better_tbl = 1;
- rs_move_next_action(tbl, IWL_MIMO2_LAST_ACTION);
- if (update_search_tbl_counter)
- search_tbl->action = tbl->action;
-
- return 0;
-}
-
/*
* Check whether we should continue using same modulation mode, or
* begin search for a new mode, based on:
@@ -1582,7 +1361,7 @@ static void rs_stay_in_table(struct iwl_lq_sta *lq_sta, bool force_search)
tbl = &(lq_sta->lq_info[active_tbl]);
/* If we've been disallowing search, see if we should now allow it */
- if (lq_sta->stay_in_tbl) {
+ if (lq_sta->rs_state == RS_STATE_STAY_IN_COLUMN) {
/* Elapsed time using current modulation mode */
if (lq_sta->flush_timer)
flush_interval_passed =
@@ -1610,10 +1389,14 @@ static void rs_stay_in_table(struct iwl_lq_sta *lq_sta, bool force_search)
flush_interval_passed);
/* Allow search for new mode */
- lq_sta->stay_in_tbl = 0; /* only place reset */
+ lq_sta->rs_state = RS_STATE_SEARCH_CYCLE_STARTED;
+ IWL_DEBUG_RATE(mvm,
+ "Moving to RS_STATE_SEARCH_CYCLE_STARTED\n");
lq_sta->total_failed = 0;
lq_sta->total_success = 0;
lq_sta->flush_timer = 0;
+ /* mark the current column as visited */
+ lq_sta->visited_columns = BIT(tbl->column);
/*
* Else if we've used this modulation mode enough repetitions
* (regardless of elapsed time or success/failure), reset
@@ -1637,7 +1420,8 @@ static void rs_stay_in_table(struct iwl_lq_sta *lq_sta, bool force_search)
/* If transitioning to allow "search", reset all history
* bitmaps and stats in active table (this will become the new
* "search" table). */
- if (!lq_sta->stay_in_tbl) {
+ if (lq_sta->rs_state == RS_STATE_SEARCH_CYCLE_STARTED) {
+ IWL_DEBUG_RATE(mvm, "Clearing up window stats\n");
for (i = 0; i < IWL_RATE_COUNT; i++)
rs_rate_scale_clear_window(&(tbl->win[i]));
}
@@ -1675,6 +1459,162 @@ static u8 rs_get_tid(struct iwl_lq_sta *lq_data,
return tid;
}
+static enum rs_column rs_get_next_column(struct iwl_mvm *mvm,
+ struct iwl_lq_sta *lq_sta,
+ struct ieee80211_sta *sta,
+ struct iwl_scale_tbl_info *tbl)
+{
+ int i, j, n;
+ enum rs_column next_col_id;
+ const struct rs_tx_column *curr_col = &rs_tx_columns[tbl->column];
+ const struct rs_tx_column *next_col;
+ allow_column_func_t allow_func;
+ u8 valid_ants = iwl_fw_valid_tx_ant(mvm->fw);
+ s32 *expected_tpt_tbl;
+ s32 tpt, max_expected_tpt;
+
+ for (i = 0; i < MAX_NEXT_COLUMNS; i++) {
+ next_col_id = curr_col->next_columns[i];
+
+ if (next_col_id == RS_COLUMN_INVALID)
+ continue;
+
+ if (lq_sta->visited_columns & BIT(next_col_id)) {
+ IWL_DEBUG_RATE(mvm, "Skip already visited column %d\n",
+ next_col_id);
+ continue;
+ }
+
+ next_col = &rs_tx_columns[next_col_id];
+
+ if (!rs_is_valid_ant(valid_ants, next_col->ant)) {
+ IWL_DEBUG_RATE(mvm,
+ "Skip column %d as ANT config isn't supported by chip. valid_ants 0x%x column ant 0x%x\n",
+ next_col_id, valid_ants, next_col->ant);
+ continue;
+ }
+
+ for (j = 0; j < MAX_COLUMN_CHECKS; j++) {
+ allow_func = next_col->checks[j];
+ if (allow_func && !allow_func(mvm, sta, tbl))
+ break;
+ }
+
+ if (j != MAX_COLUMN_CHECKS) {
+ IWL_DEBUG_RATE(mvm,
+ "Skip column %d: not allowed (check %d failed)\n",
+ next_col_id, j);
+
+ continue;
+ }
+
+ tpt = lq_sta->last_tpt / 100;
+ expected_tpt_tbl = rs_get_expected_tpt_table(lq_sta, next_col,
+ tbl->rate.bw);
+ if (WARN_ON_ONCE(!expected_tpt_tbl))
+ continue;
+
+ max_expected_tpt = 0;
+ for (n = 0; n < IWL_RATE_COUNT; n++)
+ if (expected_tpt_tbl[n] > max_expected_tpt)
+ max_expected_tpt = expected_tpt_tbl[n];
+
+ if (tpt >= max_expected_tpt) {
+ IWL_DEBUG_RATE(mvm,
+ "Skip column %d: can't beat current TPT. Max expected %d current %d\n",
+ next_col_id, max_expected_tpt, tpt);
+ continue;
+ }
+
+ break;
+ }
+
+ if (i == MAX_NEXT_COLUMNS)
+ return RS_COLUMN_INVALID;
+
+ IWL_DEBUG_RATE(mvm, "Found potential column %d\n", next_col_id);
+
+ return next_col_id;
+}
+
+static int rs_switch_to_column(struct iwl_mvm *mvm,
+ struct iwl_lq_sta *lq_sta,
+ struct ieee80211_sta *sta,
+ enum rs_column col_id)
+{
+ struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
+ struct iwl_scale_tbl_info *search_tbl =
+ &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
+ struct rs_rate *rate = &search_tbl->rate;
+ const struct rs_tx_column *column = &rs_tx_columns[col_id];
+ const struct rs_tx_column *curr_column = &rs_tx_columns[tbl->column];
+ u32 sz = (sizeof(struct iwl_scale_tbl_info) -
+ (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
+ u16 rate_mask = 0;
+ u32 rate_idx = 0;
+
+ memcpy(search_tbl, tbl, sz);
+
+ rate->sgi = column->sgi;
+ rate->ant = column->ant;
+
+ if (column->mode == RS_LEGACY) {
+ if (lq_sta->band == IEEE80211_BAND_5GHZ)
+ rate->type = LQ_LEGACY_A;
+ else
+ rate->type = LQ_LEGACY_G;
+
+ rate_mask = lq_sta->active_legacy_rate;
+ } else if (column->mode == RS_SISO) {
+ rate->type = lq_sta->is_vht ? LQ_VHT_SISO : LQ_HT_SISO;
+ rate_mask = lq_sta->active_siso_rate;
+ } else if (column->mode == RS_MIMO2) {
+ rate->type = lq_sta->is_vht ? LQ_VHT_MIMO2 : LQ_HT_MIMO2;
+ rate_mask = lq_sta->active_mimo2_rate;
+ } else {
+ WARN_ON_ONCE("Bad column mode");
+ }
+
+ rate->bw = rs_bw_from_sta_bw(sta);
+ search_tbl->column = col_id;
+ rs_set_expected_tpt_table(lq_sta, search_tbl);
+
+ /* Get the best matching rate if we're changing modes. e.g.
+ * SISO->MIMO, LEGACY->SISO, MIMO->SISO
+ */
+ if (curr_column->mode != column->mode) {
+ rate_idx = rs_get_best_rate(mvm, lq_sta, search_tbl,
+ rate_mask, rate->index);
+
+ if ((rate_idx == IWL_RATE_INVALID) ||
+ !(BIT(rate_idx) & rate_mask)) {
+ IWL_DEBUG_RATE(mvm,
+ "can not switch with index %d"
+ " rate mask %x\n",
+ rate_idx, rate_mask);
+
+ goto err;
+ }
+
+ rate->index = rate_idx;
+ }
+
+ /* TODO: remove current_rate and keep using rs_rate all the way until
+ * we need to fill in the rs_table in the LQ command
+ */
+ search_tbl->current_rate = ucode_rate_from_rs_rate(mvm, rate);
+ IWL_DEBUG_RATE(mvm, "Switched to column %d: Index %d\n",
+ col_id, rate->index);
+
+ lq_sta->visited_columns |= BIT(col_id);
+ return 0;
+
+err:
+ rate->type = LQ_NONE;
+ return -1;
+}
+
+
/*
* Do rate scaling and search for new modulation mode.
*/
@@ -1772,7 +1712,7 @@ static void rs_rate_scale_perform(struct iwl_mvm *mvm,
if (!rate_scale_index_msk)
rate_scale_index_msk = rate_mask;
- if (!((1 << index) & rate_scale_index_msk)) {
+ if (!((BIT(index) & rate_scale_index_msk))) {
IWL_ERR(mvm, "Current Rate is not valid\n");
if (lq_sta->search_better_tbl) {
/* revert to active table if search table is not valid*/
@@ -1852,9 +1792,6 @@ static void rs_rate_scale_perform(struct iwl_mvm *mvm,
window->average_tpt,
lq_sta->last_tpt);
- if (!is_legacy(rate))
- lq_sta->enable_counter = 1;
-
/* Swap tables; "search" becomes "active" */
lq_sta->active_tbl = active_tbl;
current_tpt = window->average_tpt;
@@ -2049,24 +1986,29 @@ lq_update:
* 3) Allowing a new search
*/
if (!update_lq && !done_search &&
- !lq_sta->stay_in_tbl && window->counter) {
+ lq_sta->rs_state == RS_STATE_SEARCH_CYCLE_STARTED
+ && window->counter) {
+ enum rs_column next_column;
+
/* Save current throughput to compare with "search" throughput*/
lq_sta->last_tpt = current_tpt;
IWL_DEBUG_RATE(mvm,
- "Start Search: update_lq %d done_search %d stay_in_tbl %d win->counter %d\n",
- update_lq, done_search, lq_sta->stay_in_tbl,
+ "Start Search: update_lq %d done_search %d rs_state %d win->counter %d\n",
+ update_lq, done_search, lq_sta->rs_state,
window->counter);
- /* Select a new "search" modulation mode to try.
- * If one is found, set up the new "search" table. */
- if (is_legacy(&tbl->rate))
- rs_move_legacy_other(mvm, lq_sta, sta, index);
- else if (is_siso(&tbl->rate))
- rs_move_siso_to_other(mvm, lq_sta, sta, index);
- else if (is_mimo2(&tbl->rate))
- rs_move_mimo2_to_other(mvm, lq_sta, sta, index);
- else
- WARN_ON_ONCE(1);
+
+ next_column = rs_get_next_column(mvm, lq_sta, sta, tbl);
+ if (next_column != RS_COLUMN_INVALID) {
+ int ret = rs_switch_to_column(mvm, lq_sta, sta,
+ next_column);
+ if (!ret)
+ lq_sta->search_better_tbl = 1;
+ } else {
+ IWL_DEBUG_RATE(mvm,
+ "No more columns to explore in search cycle. Go to RS_STATE_SEARCH_CYCLE_ENDED\n");
+ lq_sta->rs_state = RS_STATE_SEARCH_CYCLE_ENDED;
+ }
/* If new "search" mode was selected, set up in uCode table */
if (lq_sta->search_better_tbl) {
@@ -2078,12 +2020,8 @@ lq_update:
/* Use new "search" start rate */
index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
- IWL_DEBUG_RATE(mvm,
- "Switch to SEARCH TABLE: "
- "mcs %X (%s: %d)\n",
- tbl->current_rate,
- rs_pretty_lq_type(tbl->rate.type),
- index);
+ rs_dump_rate(mvm, &tbl->rate,
+ "Switch to SEARCH TABLE:");
rs_fill_link_cmd(mvm, sta, lq_sta, tbl->current_rate);
iwl_mvm_send_lq_cmd(mvm, &lq_sta->lq, false);
} else {
@@ -2091,24 +2029,20 @@ lq_update:
}
}
- if (done_search && !lq_sta->stay_in_tbl) {
+ if (done_search && lq_sta->rs_state == RS_STATE_SEARCH_CYCLE_ENDED) {
/* If the "active" (non-search) mode was legacy,
* and we've tried switching antennas,
* but we haven't been able to try HT modes (not available),
* stay with best antenna legacy modulation for a while
* before next round of mode comparisons. */
tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
- if (is_legacy(&tbl1->rate) && !sta->ht_cap.ht_supported &&
- lq_sta->action_counter > tbl1->max_search) {
+ if (is_legacy(&tbl1->rate) && !sta->ht_cap.ht_supported) {
IWL_DEBUG_RATE(mvm, "LQ: STAY in legacy table\n");
rs_set_stay_in_table(mvm, 1, lq_sta);
- }
-
+ } else {
/* If we're in an HT mode, and all 3 mode switch actions
* have been tried and compared, stay in this best modulation
* mode for a while before next round of mode comparisons. */
- if (lq_sta->enable_counter &&
- (lq_sta->action_counter >= tbl1->max_search)) {
if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
(lq_sta->tx_agg_tid_en & (1 << tid)) &&
(tid != IWL_MAX_TID_COUNT)) {
@@ -2176,19 +2110,24 @@ static void rs_initialize_lq(struct iwl_mvm *mvm,
if ((i < 0) || (i >= IWL_RATE_COUNT))
i = 0;
- ucode_rate = iwl_rates[i].plcp;
+ rate->index = i;
rate->ant = first_antenna(valid_tx_ant);
- ucode_rate |= rate->ant << RATE_MCS_ANT_POS;
-
- if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
- ucode_rate |= RATE_MCS_CCK_MSK;
-
- rs_rate_from_ucode_rate(ucode_rate, band, rate);
- if (!rs_is_valid_ant(valid_tx_ant, rate->ant))
- rs_toggle_antenna(valid_tx_ant, &ucode_rate, rate);
+ rate->sgi = false;
+ rate->bw = RATE_MCS_CHAN_WIDTH_20;
+ if (band == IEEE80211_BAND_5GHZ)
+ rate->type = LQ_LEGACY_A;
+ else
+ rate->type = LQ_LEGACY_G;
ucode_rate = ucode_rate_from_rs_rate(mvm, rate);
tbl->current_rate = ucode_rate;
+
+ WARN_ON_ONCE(rate->ant != ANT_A && rate->ant != ANT_B);
+ if (rate->ant == ANT_A)
+ tbl->column = RS_COLUMN_LEGACY_ANT_A;
+ else
+ tbl->column = RS_COLUMN_LEGACY_ANT_B;
+
rs_set_expected_tpt_table(lq_sta, tbl);
rs_fill_link_cmd(NULL, NULL, lq_sta, ucode_rate);
/* TODO restore station should remember the lq cmd */
diff --git a/drivers/net/wireless/iwlwifi/mvm/rs.h b/drivers/net/wireless/iwlwifi/mvm/rs.h
index 8fa26af..b329607 100644
--- a/drivers/net/wireless/iwlwifi/mvm/rs.h
+++ b/drivers/net/wireless/iwlwifi/mvm/rs.h
@@ -157,37 +157,6 @@ enum {
#define IWL_RATE_INCREASE_TH 6400 /* 50% */
#define RS_SR_FORCE_DECREASE 1920 /* 15% */
-/* possible actions when in legacy mode */
-enum {
- IWL_LEGACY_SWITCH_ANTENNA,
- IWL_LEGACY_SWITCH_SISO,
- IWL_LEGACY_SWITCH_MIMO2,
- IWL_LEGACY_FIRST_ACTION = IWL_LEGACY_SWITCH_ANTENNA,
- IWL_LEGACY_LAST_ACTION = IWL_LEGACY_SWITCH_MIMO2,
-};
-
-/* possible actions when in siso mode */
-enum {
- IWL_SISO_SWITCH_ANTENNA,
- IWL_SISO_SWITCH_MIMO2,
- IWL_SISO_SWITCH_GI,
- IWL_SISO_FIRST_ACTION = IWL_SISO_SWITCH_ANTENNA,
- IWL_SISO_LAST_ACTION = IWL_SISO_SWITCH_GI,
-};
-
-/* possible actions when in mimo mode */
-enum {
- IWL_MIMO2_SWITCH_SISO_A,
- IWL_MIMO2_SWITCH_SISO_B,
- IWL_MIMO2_SWITCH_GI,
- IWL_MIMO2_FIRST_ACTION = IWL_MIMO2_SWITCH_SISO_A,
- IWL_MIMO2_LAST_ACTION = IWL_MIMO2_SWITCH_GI,
-};
-
-#define IWL_MAX_SEARCH IWL_MIMO2_LAST_ACTION
-
-#define IWL_ACTION_LIMIT 3 /* # possible actions */
-
#define LINK_QUAL_AGG_TIME_LIMIT_DEF (4000) /* 4 milliseconds */
#define LINK_QUAL_AGG_TIME_LIMIT_MAX (8000)
#define LINK_QUAL_AGG_TIME_LIMIT_MIN (100)
@@ -282,6 +251,23 @@ struct iwl_rate_scale_data {
s32 average_tpt; /* success ratio * expected throughput */
};
+/* Possible Tx columns
+ * Tx Column = a combo of legacy/siso/mimo x antenna x SGI
+ */
+enum rs_column {
+ RS_COLUMN_LEGACY_ANT_A = 0,
+ RS_COLUMN_LEGACY_ANT_B,
+ RS_COLUMN_SISO_ANT_A,
+ RS_COLUMN_SISO_ANT_B,
+ RS_COLUMN_SISO_ANT_A_SGI,
+ RS_COLUMN_SISO_ANT_B_SGI,
+ RS_COLUMN_MIMO2,
+ RS_COLUMN_MIMO2_SGI,
+
+ RS_COLUMN_LAST = RS_COLUMN_MIMO2_SGI,
+ RS_COLUMN_INVALID,
+};
+
/**
* struct iwl_scale_tbl_info -- tx params and success history for all rates
*
@@ -290,13 +276,18 @@ struct iwl_rate_scale_data {
*/
struct iwl_scale_tbl_info {
struct rs_rate rate;
- u8 action; /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
- u8 max_search; /* maximun number of tables we can search */
+ enum rs_column column;
s32 *expected_tpt; /* throughput metrics; expected_tpt_G, etc. */
u32 current_rate; /* rate_n_flags, uCode API format */
struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
};
+enum {
+ RS_STATE_SEARCH_CYCLE_STARTED,
+ RS_STATE_SEARCH_CYCLE_ENDED,
+ RS_STATE_STAY_IN_COLUMN,
+};
+
/**
* struct iwl_lq_sta -- driver's rate scaling private structure
*
@@ -304,8 +295,7 @@ struct iwl_scale_tbl_info {
*/
struct iwl_lq_sta {
u8 active_tbl; /* index of active table, range 0-1 */
- u8 enable_counter; /* indicates HT mode */
- u8 stay_in_tbl; /* 1: disallow, 0: allow search for new mode */
+ u8 rs_state; /* RS_STATE_* */
u8 search_better_tbl; /* 1: currently trying alternate mode */
s32 last_tpt;
@@ -318,7 +308,9 @@ struct iwl_lq_sta {
u32 total_success; /* total successful frames, any/all rates */
u64 flush_timer; /* time staying in mode before new search */
- u8 action_counter; /* # mode-switch actions tried */
+ u32 visited_columns; /* Bitmask marking which Tx columns were
+ * explored during a search cycle
+ */
bool is_vht;
enum ieee80211_band band;
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