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Subject: Re: [PATCH 3/6] nl80211: add support to send EHT capabilities from
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To:     Johannes Berg <johannes@sipsolutions.net>
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From:   Veerendranath Jakkam <quic_vjakkam@quicinc.com>
Message-ID: <0644274d-7a9f-642c-eef2-02c662a5adcc@quicinc.com>
Date:   Fri, 4 Feb 2022 12:42:13 +0530
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On 2/3/22 6:15 PM, Johannes Berg wrote:
> On Wed, 2021-12-22 at 14:34 +0530, Veerendranath Jakkam wrote:
>>   
>> +#define NL80211_EHT_MIN_CAPABILITY_LEN           10
>> +#define NL80211_EHT_MAX_CAPABILITY_LEN           81
>>
> How did you get to 81?
>
> I calculate only 51, based on the assumption that we can only have
> NSS==8. Even if you think NSS==16 (which I doubt), I get to 80 only?
>
> johannes

I considered max values for NSS and RU Index Bitmask sub-fields in PPE 
threshold field.

i.e. NSS=16, RU Index Bitmask = 0x11111 with this max PPE threshold info 
sub-field length is 60 bytes


Max PPE thresholds field length = 4 bits (for NSS) + 5 bits (for RU 
Index Bitmask) +  480 bits (PPE info) + 7 bits (PPE pad)= 62 bytes

EHT fixed fields length = 10 bytes

Max MCS-NSS Set field length = 9 bytes

So total max length would be 81 bytes