Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <CA+zRt5HKvOQihOwoSj_G1eKFQ5ap9L4uRK2hvtV_SxOqwn-2Dw@mail.gmail.com>
 <e02fe1f4-d837-4124-b53e-cf8b28105a17@lockie.ca> <CA+zRt5GTSbKBjARaD19V7oQEkXUJJz_pvYO1fOXA9hPrzPS1sg@mail.gmail.com>
 <c4b24c16-788b-4f15-ae68-8df44e60a27d@lockie.ca> <b3c5f2f05d0844dfb4e9f7e943b4cbbd@realtek.com>
In-Reply-To: <b3c5f2f05d0844dfb4e9f7e943b4cbbd@realtek.com>
From:   Giulio Paci <giuliopaci@gmail.com>
Date:   Wed, 28 Jun 2023 12:35:17 +0200
Message-ID: <CA+zRt5HyZaOvDpVUxF9Rfv4rrx4Us1Krs+TeiP-U9QsrA_SX6A@mail.gmail.com>
Subject: Re: Realtek 8822ce connection is very unstable
To:     Ping-Ke Shih <pkshih@realtek.com>
Cc:     James <bjlockie@lockie.ca>, linux-wireless@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Il mer 28 giu 2023, 03:29 Ping-Ke Shih <pkshih@realtek.com> ha scritto:
> Try below options to see if they can help:
>
> 1. try another band (switch from 2GHz to 5GHz or opposite)

I tried to force 5GHz. And then to force 2GHz. When connected to 5GHz
it seems a little bit more stable, but still hangs within seconds.

> 2. try another AP

I have tried 2 different AP, but the situation is very similar with
both. One of them supports only b/g/n, so I was able to change band
only with the other one (which is a hotspot on Android phone).

> 3. disable WiFi power save by
>    rtw88_core.ko disable_lps_deep=1
>    or
>    iw wlan0 set power_save off

I tried setting disable_lps_deep=1, but still the connection seems unstable.

> By the way, when you try disable_aspm=1 and disable_msi=1, I suggest to
> create a file and add them to /etc/modprobe.d/, and then shutdown and turn on
> your computer after a while. Because some PCI settings are persistent if only
> do rmmod/insmod.

I confirm this is the approach I used in all my attempts, including
disable_lps_deep=1.
I also checked /sys/module/$module/parameters/$option content, to
confirm that the options were correctly set.

I have also carried out some additional attempts:

- boot with iommu.passthrough=1 instead of pcie_aspm=off, but it does
not seem to improve anything (and AER errors came back in the dmesg);
- After my comments on https://github.com/lwfinger/rtw88/issues/150,
https://github.com/lwfinger/rtw88/ was updated and I was able to load
these modules. The connection is still very unstable, but with these
modules, when the connection hangs, dmesg reports:

rtw_8822ce 0000:03:00.0: firmware failed to leave lps state

sometimes followed by:

rtw_8822ce 0000:03:00.0: failed to send h2c command

I have tried to set some of the options above using modules from
https://github.com/lwfinger/rtw88/, but so far, apart from these
additional messages, the results are almost identical to the
precompiled modules that come with Debian.


One of my colleagues has the same hardware (same AP model and same
laptop model) and also tried to install Debian bookworm on it. I asked
to check if he experiences the same issue, but in his case he was able
to stay connected for a few hours without any issue.
I wonder if the issue I am experiencing could be due to defective
hardware (initially I excluded it since the same configuration is very
stable under Windows). Is there any specific test that I can try to
exclude hardware issues?

Bests,
Giulio