Re: [PATCH 2/2] wifi: ath12k: Add support for MLO Multicast handling in driver

[Balamurugan Mahalingam <quic_bmahalin@quicinc.com>]

On 1/24/2025 3:45 AM, Nicolas Escande wrote:
> On Thu Jan 9, 2025 at 7:49 PM CET, Balamurugan Mahalingam wrote:
> [...]
>> diff --git a/drivers/net/wireless/ath/ath12k/dp_tx.c b/drivers/net/wireless/ath/ath12k/dp_tx.c
>> index 76626d925adf..9d05fe7a870c 100644
>> --- a/drivers/net/wireless/ath/ath12k/dp_tx.c
>> +++ b/drivers/net/wireless/ath/ath12k/dp_tx.c
>> @@ -217,7 +217,7 @@ static int ath12k_dp_tx_align_payload(struct ath12k_base *ab,
>>   }
>>   
>>   int ath12k_dp_tx(struct ath12k *ar, struct ath12k_link_vif *arvif,
>> -		 struct sk_buff *skb)
>> +		 struct sk_buff *skb, bool gsn_valid, int mcbc_gsn)
>>   {
>>   	struct ath12k_base *ab = ar->ab;
>>   	struct ath12k_dp *dp = &ab->dp;
>> @@ -290,13 +290,24 @@ int ath12k_dp_tx(struct ath12k *ar, struct ath12k_link_vif *arvif,
>>   		msdu_ext_desc = true;
>>   	}
>>   
>> +	if (gsn_valid) {
>> +		ti.meta_data_flags =
>> +			u32_encode_bits(HTT_TCL_META_DATA_TYPE_GLOBAL_SEQ_NUM,
>> +					HTT_TCL_META_DATA_TYPE) |
>> +			u32_encode_bits(mcbc_gsn, HTT_TCL_META_DATA_GLOBAL_SEQ_NUM);
>> +	}
>> +
> Hello,
> 
> As ti is zeroed initilised isn't safer to do 'ti.meta_data_flags |='
> instead of 'ti.meta_data_flags ='. This way if we add another flag in
> meta_data_flag in the same func for another reason, we will have less risk of
> overriding the said flags ?
> 

Hello Nicolas,
In this case, this is an intentional reset of any previous residual 
value in ti.meta_data_flags field.
The meta_data_flags bit definition is different depending upon the 
META_DATA_TYPE bit's value.

>>   	ti.encap_type = ath12k_dp_tx_get_encap_type(arvif, skb);
>>   	ti.addr_search_flags = arvif->hal_addr_search_flags;
>>   	ti.search_type = arvif->search_type;
>>   	ti.type = HAL_TCL_DESC_TYPE_BUFFER;
>>   	ti.pkt_offset = 0;
>>   	ti.lmac_id = ar->lmac_id;
>> -	ti.vdev_id = arvif->vdev_id;
>> +	if (gsn_valid)
>> +		ti.vdev_id = arvif->vdev_id +
>> +			     HTT_TX_MLO_MCAST_HOST_REINJECT_BASE_VDEV_ID;
>> +	else
>> +		ti.vdev_id = arvif->vdev_id;
>>   	ti.bss_ast_hash = arvif->ast_hash;
>>   	ti.bss_ast_idx = arvif->ast_idx;
>>   	ti.dscp_tid_tbl_idx = 0;