wifi: ath12k: prepare sta data structure for MLO handling

To prepare the driver for MLO support, split the driver sta data structure to
scale for multiple links. This requires changing the use of arsta to per link
and not per hw which can now comprise of multiple links. Also since most
configurations from mac80211 are done per link, do refactoring of the driver
functions to apply these configurations at link level.

Split struct ath12k_sta, which is the driver private of struct ieee80211_sta,
to store link specific information as struct ath12k_link_sta. For default use
cases struct ath12k_sta will have a preallocated link sta called deflink which
will be used by non ML STAs and the first link sta of ML STA.

With MLO support to be added, remaining link stas will allocated during state
change where new STA is added. These link stas will be freed when STA is
deleted.

Current ath12k_sta(arsta) structure:

	 +-----------------+       +----------------+
	 |                 |       |                |
	 |   ieee80211_sta |       |  ieee80211_sta |
	 |   private data  |       |  private data  |
	 |                 |       |                |
	 |   ath12k_sta    |       |  ath12k_sta    |
	 |   (arsta)       |       |   (arsta)      |
	 |+---------------+|       | +-------------+|
	 || *arvif (link  ||       | |*arvif (link ||
	 || vif of an ar  ||       | | vif of an ar||
	 || say 5GHz)     ||       | | say 6GHz)   ||
	 |+---------------+|       | +-------------+|
	 +-----------------+       +----------------+

New struct ath12k_sta (ahsta) containing ath12k_link_sta(s) (arsta) (deflink is
preallocated member which is always the first link if ieee80211_sta is ML STA
and is the only link sta otherwise):

		+---------------------------------------+
		|         ieee80211_sta                 |
		|         private data                  |
		|                                       |
		|         ath12k_sta (ahsta)            |
		| +-------------------------------------+
		| | ath12k_link_sta deflink (arsta)     |
		| |                                     |
		| |  *arvif (link vif of ar (5GHz))     |
		| +-------------------------------------+
		| +-------------------------------------+
		| | ath12k_link_sta *link (arsta)       |
		| |                                     |
		| |   *arvif (link vif of ar (6GHz))    |
		| |                                     |
		| +-------------------------------------+
		|                                       |
		+---------------------------------------+

To refactor existing ath12k_sta to make use of link stas, following changes are
made:

 1. Limit struct ieee80211_sta argument mac80211 ops unless otherwise really required.

 2. struct ath12k_sta, now called by variable name arsta, stores multiple
    arstas (struct ah12k_link_sta) and also has a back pointer to struct
    ath12k_sta.

 3. Pass struct ath12k_link_sta to mac functions that passed struct
    ieee80211_sta argument and fetch struct ath12k_sta (ahsta) and struct
    ieee80211_sta(sta) internally. This is done to avoid passing link id in all
    the functions and performing validation across these functions. Rather the
    validation and sta to arsta conversion can be done only at the mac80211 ops.

 4. In this patchset, only ahsta->deflink is used to be on par with the
    existing code. When MLO support is added the link id will be used to fetch the
    arsta.

 5. Change ath12k_sta_to_arsta() to ath12k_vif_to_ahsta() to fetch the
    ML level sta. The link sta can be fetched from ahsta->link[], or the
    deflink can be accessed via ahsta->deflink. API to access link
    sta (arsta) by passing link_id can be introduced with MLO Support.

 6. The ieee80211_sta can be accessed from ahsta using ath12k_ahsta_to_sta()

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0.1-00029-QCAHKSWPL_SILICONZ-1
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Signed-off-by: Sriram R <quic_srirrama@quicinc.com>
Co-developed-by: Rameshkumar Sundaram <quic_ramess@quicinc.com>
Signed-off-by: Rameshkumar Sundaram <quic_ramess@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://patch.msgid.link/20241015171416.518022-4-kvalo@kernel.org
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>

drivers/net/wireless/ath/ath12k/core.h

@@ -456,27 +456,36 @@ struct ath12k_wbm_tx_stats {
 	u64 wbm_tx_comp_stats[HAL_WBM_REL_HTT_TX_COMP_STATUS_MAX];
 };
 
-struct ath12k_sta {
+struct ath12k_link_sta {
 	struct ath12k_link_vif *arvif;
+	struct ath12k_sta *ahsta;
 
 	/* the following are protected by ar->data_lock */
 	u32 changed; /* IEEE80211_RC_* */
 	u32 bw;
 	u32 nss;
 	u32 smps;
-	enum hal_pn_type pn_type;
 
 	struct wiphy_work update_wk;
 	struct rate_info txrate;
 	struct rate_info last_txrate;
 	u64 rx_duration;
 	u64 tx_duration;
 	u8 rssi_comb;
+	u8 link_id;
 	struct ath12k_rx_peer_stats *rx_stats;
 	struct ath12k_wbm_tx_stats *wbm_tx_stats;
 	u32 bw_prev;
 };
 
+struct ath12k_sta {
+	enum hal_pn_type pn_type;
+	struct ath12k_link_sta deflink;
+	struct ath12k_link_sta __rcu *link[IEEE80211_MLD_MAX_NUM_LINKS];
+	/* indicates bitmap of link sta created in FW */
+	u16 links_map;
+};
+
 #define ATH12K_MIN_5G_FREQ 4150
 #define ATH12K_MIN_6G_FREQ 5925
 #define ATH12K_MAX_6G_FREQ 7115
@@ -1046,11 +1055,16 @@ static inline struct ath12k_vif *ath12k_vif_to_ahvif(struct ieee80211_vif *vif)
 	return (struct ath12k_vif *)vif->drv_priv;
 }
 
-static inline struct ath12k_sta *ath12k_sta_to_arsta(struct ieee80211_sta *sta)
+static inline struct ath12k_sta *ath12k_sta_to_ahsta(struct ieee80211_sta *sta)
 {
 	return (struct ath12k_sta *)sta->drv_priv;
 }
 
+static inline struct ieee80211_sta *ath12k_ahsta_to_sta(struct ath12k_sta *ahsta)
+{
+	return container_of((void *)ahsta, struct ieee80211_sta, drv_priv);
+}
+
 static inline struct ieee80211_vif *ath12k_ahvif_to_vif(struct ath12k_vif *ahvif)
 {
 	return container_of((void *)ahvif, struct ieee80211_vif, drv_priv);

drivers/net/wireless/ath/ath12k/dp_mon.c

@@ -2165,7 +2165,7 @@ ath12k_dp_mon_rx_update_peer_rate_table_stats(struct ath12k_rx_peer_stats *rx_st
 }
 
 static void ath12k_dp_mon_rx_update_peer_su_stats(struct ath12k *ar,
-						  struct ath12k_sta *arsta,
+						  struct ath12k_link_sta *arsta,
 						  struct hal_rx_mon_ppdu_info *ppdu_info)
 {
 	struct ath12k_rx_peer_stats *rx_stats = arsta->rx_stats;
@@ -2321,7 +2321,8 @@ ath12k_dp_mon_rx_update_user_stats(struct ath12k *ar,
 				   struct hal_rx_mon_ppdu_info *ppdu_info,
 				   u32 uid)
 {
-	struct ath12k_sta *arsta = NULL;
+	struct ath12k_sta *ahsta;
+	struct ath12k_link_sta *arsta;
 	struct ath12k_rx_peer_stats *rx_stats = NULL;
 	struct hal_rx_user_status *user_stats = &ppdu_info->userstats[uid];
 	struct ath12k_peer *peer;
@@ -2338,7 +2339,8 @@ ath12k_dp_mon_rx_update_user_stats(struct ath12k *ar,
 		return;
 	}
 
-	arsta = ath12k_sta_to_arsta(peer->sta);
+	ahsta = ath12k_sta_to_ahsta(peer->sta);
+	arsta = &ahsta->deflink;
 	rx_stats = arsta->rx_stats;
 
 	if (!rx_stats)
@@ -2445,7 +2447,8 @@ int ath12k_dp_mon_rx_process_stats(struct ath12k *ar, int mac_id,
 	struct dp_srng *mon_dst_ring;
 	struct hal_srng *srng;
 	struct dp_rxdma_mon_ring *buf_ring;
-	struct ath12k_sta *arsta = NULL;
+	struct ath12k_sta *ahsta = NULL;
+	struct ath12k_link_sta *arsta;
 	struct ath12k_peer *peer;
 	u64 cookie;
 	int num_buffs_reaped = 0, srng_id, buf_id;
@@ -2514,7 +2517,8 @@ int ath12k_dp_mon_rx_process_stats(struct ath12k *ar, int mac_id,
 			}
 
 			if (ppdu_info->reception_type == HAL_RX_RECEPTION_TYPE_SU) {
-				arsta = ath12k_sta_to_arsta(peer->sta);
+				ahsta = ath12k_sta_to_ahsta(peer->sta);
+				arsta = &ahsta->deflink;
 				ath12k_dp_mon_rx_update_peer_su_stats(ar, arsta,
 								      ppdu_info);
 			} else if ((ppdu_info->fc_valid) &&

drivers/net/wireless/ath/ath12k/dp_rx.c

@@ -1041,13 +1041,14 @@ int ath12k_dp_rx_ampdu_start(struct ath12k *ar,
 			     struct ieee80211_ampdu_params *params)
 {
 	struct ath12k_base *ab = ar->ab;
-	struct ath12k_sta *arsta = ath12k_sta_to_arsta(params->sta);
+	struct ath12k_sta *ahsta = ath12k_sta_to_ahsta(params->sta);
+	struct ath12k_link_sta *arsta = &ahsta->deflink;
 	int vdev_id = arsta->arvif->vdev_id;
 	int ret;
 
 	ret = ath12k_dp_rx_peer_tid_setup(ar, params->sta->addr, vdev_id,
 					  params->tid, params->buf_size,
-					  params->ssn, arsta->pn_type);
+					  params->ssn, arsta->ahsta->pn_type);
 	if (ret)
 		ath12k_warn(ab, "failed to setup rx tid %d\n", ret);
 
@@ -1059,7 +1060,8 @@ int ath12k_dp_rx_ampdu_stop(struct ath12k *ar,
 {
 	struct ath12k_base *ab = ar->ab;
 	struct ath12k_peer *peer;
-	struct ath12k_sta *arsta = ath12k_sta_to_arsta(params->sta);
+	struct ath12k_sta *ahsta = ath12k_sta_to_ahsta(params->sta);
+	struct ath12k_link_sta *arsta = &ahsta->deflink;
 	int vdev_id = arsta->arvif->vdev_id;
 	bool active;
 	int ret;
@@ -1313,7 +1315,8 @@ ath12k_update_per_peer_tx_stats(struct ath12k *ar,
 	struct ath12k_base *ab = ar->ab;
 	struct ath12k_peer *peer;
 	struct ieee80211_sta *sta;
-	struct ath12k_sta *arsta;
+	struct ath12k_sta *ahsta;
+	struct ath12k_link_sta *arsta;
 	struct htt_ppdu_stats_user_rate *user_rate;
 	struct ath12k_per_peer_tx_stats *peer_stats = &ar->peer_tx_stats;
 	struct htt_ppdu_user_stats *usr_stats = &ppdu_stats->user_stats[user];
@@ -1394,7 +1397,8 @@ ath12k_update_per_peer_tx_stats(struct ath12k *ar,
 	}
 
 	sta = peer->sta;
-	arsta = ath12k_sta_to_arsta(sta);
+	ahsta = ath12k_sta_to_ahsta(sta);
+	arsta = &ahsta->deflink;
 
 	memset(&arsta->txrate, 0, sizeof(arsta->txrate));