RE: EFUSE in RTW8723DS

[Ping-Ke Shih <pkshih@realtek.com>]

> -----Original Message-----
> From: Larry Finger <larry.finger@gmail.com> On Behalf Of Larry Finger
> Sent: Saturday, November 11, 2023 4:26 AM
> To: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> Cc: linux-wireless <linux-wireless@vger.kernel.org>
> Subject: EFUSE in RTW8723DS
> 
> Martin,
> 
> The commit 9be20a822327 ("wifi: rtw88: rtw8723d: Implement RTL8723DS (SDIO)
> efuse parsing") indicates that no additional information is extracted from the
> EFUSE? Is that true, or did I misread the code?

I think the commit is only to read MAC address that is programmed in different
location from PCI interface, and no more information. 

> 
> One problem we are having is that some devices come with zero programming in the
> EFUSE, and even with supplying a valid MAC address, the performance is poor.

One or two years ago, people reported efuse of RTL8192DE (IIRC) isn't programmed
in OpenWRT platform originally. That kind of product, calibration values are stored
in external files instead, and chip is soldered on main board instead of a
separated hardware module such M.2.

Maybe, we can read calibration values programmed in efuse as _default_ values
from another module. This can't yield the best performance, but at least better
than nothing. 

Ping-Ke