Re: [PATCH 1/4] rtlwifi: rtl8723ae: Take the FW LPS mode handling out

From: Larry Finger
Date: Fri Jan 04 2019 - 21:44:50 EST

On 1/4/19 6:48 AM, Bernd Edlinger wrote:
This appears to trigger a firmware bug and causes severe
problems with rtl8723ae PCI devices.

When the power save mode is activated for longer periods
of time the firmware stops to receive any packets.

This problem was exposed by commit 873ffe154ae0 ("rtlwifi:
Fix logic error in enter/exit power-save mode").

Previously the power save mode was only active rarely and
only for a short time so that the problem was not noticeable.

Signed-off-by: Bernd Edlinger <bernd.edlinger@xxxxxxxxxx>

While the Realtek firmware group has a chance to look for a bug, I would like you to perform a couple of tests on the original code.

The driver has three module parameters that affect power save. The 'modinfo rtl8723ae' command lists them as

parm: ips:Set to 0 to not use link power save (default 1) (bool)
parm: swlps:Set to 1 to use SW control power save (default 0) (bool)
parm: fwlps:Set to 1 to use FW control power save (default 1) (bool)

If you were to load rtl8723ae with 'ips=0', does it still fail?
If you were to load the driver with 'swlps=1 fwlps=0', does it still fail?

Thanks for debugging this problem.