linux-kernel - Re: wifi: mt76: mt7921 Survey is missing noise floor

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CAFBinCCgiJAimacWtTS-5JRMKbpKg8XN0Si3tvBjT+tJmCg0xA@mail.gmail.com>
Date: Mon, 30 Dec 2024 21:35:54 +0100
From: Martin Blumenstingl <martin.blumenstingl@...glemail.com>
To: linux-wireless@...r.kernel.org
Cc: Felix Fietkau <nbd@....name>, Lorenzo Bianconi <lorenzo@...nel.org>, Ryder Lee <ryder.lee@...iatek.com>, 
	Shayne Chen <shayne.chen@...iatek.com>, Sean Wang <sean.wang@...iatek.com>, 
	linux-kernel@...r.kernel.org, linux-mediatek@...ts.infradead.org
Subject: Re: wifi: mt76: mt7921 Survey is missing noise floor

Hello,

On Sun, Oct 13, 2024 at 1:19 PM Martin Blumenstingl
<martin.blumenstingl@...glemail.com> wrote:
>
> Hello,
>
> I'm using an MT7921 PCIe card in AP mode on the 5GHz band.
> It works well when I manually set a channel in hostapd.conf.
>
> Setting channel=0 or channel=acs_survey (both have the same meaning)
> should make hostapd check for a suitable channel and pick that
> automatically.
> Unfortunately this does not work as hostapd reports the following (for
> all frequencies/channels):
>     ACS: Survey for freq 5180 is missing noise floor
>     ACS: Survey for freq 5180 is missing noise floor
>     ACS: Survey for freq 5180 is missing noise floor
>     ACS: Survey for freq 5180 is missing noise floor
>     ACS: Survey for freq 5180 is missing noise floor
>     ACS: Channel 36 has insufficient survey data
>
> I suspect that this is due to mt792x_phy_update_channel() (from
> drivers/net/wireless/mediatek/mt76/mt792x_mac.c) which calls
> mt792x_phy_get_nf(). The latter just returns zero - so it seems
> reading the noise floor from the hardware/firmware is not
> supported yet.
>
> What is needed to implement this? I can test patches or - if
> someone describes which registers to program - I can also write
> a patch and submit it upstream.
It's been a while so I'd like to ping the mt76 maintainers.

Also I want to point out again that I can submit a patch if someone
can provide me with the info on how to get the noise floor from the
hardware/firmware.


Best regards,
Martin