RE: [PATCH 18/20] wifi: rtw88: Add rtw8821a.{c,h}

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

Ping-Ke Shih <pkshih@realtek.com> wrote:
> Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
> > >>>>>> +
> > >>>>>> +const struct rtw_chip_info rtw8812a_hw_spec = {
> > >>>>>
> > >>>>> Is it possible moving 8812a to individual file?
> > >>>>> Since you have rtw8812au.c and rtw8821au.c.
> > >>>>>
> > >>>>
> > >>>> I think it is possible. But most of the code is common to both chips.
> > >>>> Only the IQ calibration could be moved.
> > >>>
> > >>> Yep, depend on how much IQK code echo chip has.
> > >>>
> > >>
> > >> The IQ calibration for RTL8812AU is about 700 lines.
> > >
> > > rtw8812au  -----> (a) rtw8812a
> > >                         |
> > >                         v
> > >                   (b) rtw8821a_common  (hard to give a name)
> > >                         ^
> > >                         |
> > > rtw8821au  -----> (c) rtw8821a
> > >
> > > Put all common code to (b). IQK code in (a) or (c).
> > >
> > > I feel you have thought above picture already. What are problems we will encounter?
> > > Many export symbols? If so, how about below?
> > >
> > > rtw8812au  -----> (1) rtw8812a
> > >     +---------+
> > >               +-> (2) rtw8821a_common  (hard to give a name)
> > >     +---------+
> > > rtw8821au  -----> (3) rtw8821a
> > >
> > > Put rtw8812a_hw_spec and rtw8821a_hw_spec in (2). Only IQK code in (1) and (3)
> > > respectively, and export IQK entry only. Does it work?
> > >
> > >
> > For the name of the common module, I was thinking rtw88_88xxa.ko.
> >
> > I wonder, what is the goal? To put the code in separate kernel
> > modules, or just separate files?
> 
> I would like to reduce runtime memory. As I asked, how many IQK code are different
> from them? If you have separated and compiled them, can you share size by the
> output of 'size' command?
> 
> >
> > I think we can have rtw88xxa.c (common code), rtw8821a.c (IQK code,
> > rtw8821a_hw_spec, bluetooth stuff), and rtw8812a.c (IQK code,
> > rtw8812a_hw_spec, some efuse stuff, channel switching)... if these
> > three files compile into a single module, rtw88_88xxa.ko.
> >
> > If each file compiles into a module of its own, we have circular
> > dependencies: rtw8821a_hw_spec -> common code -> IQK code.
> > If *_hw_spec go in the common module, it still depends on both of
> > the other two modules, so what use is it?
> 
> If we have dependency of common code -> IQK code, we can't save runtime
> memory, because common code reference to both IQK code. So I felt
> dependency of IQK code would be rtw8812au --> IQK code as above second
> diagram.
> 
> But if the work is complicated and save few runtime memory, we can
> use simple design as current did.
> 

Sorry. Correct typo. "... save few runtime memory ..." (remove 'not')