[PATCH 3/3] wifi: ath12k: prepare sta data structure for MLO handling

[Jeff Johnson]

On 4/22/2024 5:56 AM, Rameshkumar Sundaram wrote:
> From: Sriram R <quic_srirrama at quicinc.com>
> 
> 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 ath12k_sta which is the driver private of ieee80211_sta to store
> link specific information as ath12k_link_sta. For default use cases
> the 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)   ||
> 	 |+---------------+|       | +-------------+|
> 	 +-----------------+       +----------------+
> 
> 	Proposed 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 ieee80211_sta argument mac80211 ops unless otherwise really required.
> 
>  2. ath12k_sta now called by variable name arsta stores multiple
>     arstas(ah12k_link_sta) and also has a back pointer to ath12k_sta
> 
>  3. Pass ath12k_link_sta to mac functions that passed ieee80211_sta arg
>     and fetch ath12k_sta(ahsta) and sta(ieee80211_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_sta_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 at quicinc.com>
> Co-developed-by: Rameshkumar Sundaram <quic_ramess at quicinc.com>
> Signed-off-by: Rameshkumar Sundaram <quic_ramess at quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson at quicinc.com>