[PATCH v2 5/7] Documentation: fb: sm712fb: add information mainly about 2D.

[Tom Li]

On Sun, Mar 31, 2019 at 07:54:28PM +0100, Sudip Mukherjee wrote:
> On Fri, Mar 22, 2019 at 01:17:57PM +0800, Yifeng Li wrote:
> > +video controllers. This series of video controller is a legacy from ~1998,
> > +and was used on many classic, "prehistoric" laptops from 1998-2004, such as
> > +IBM Thinkpad S30 and 240X. It was also used on some servers, industrial
> > +computers, x86 and non-x86 embedded devices where only basic graphics was
> > +needed.
> 
> I think this is wrong. Loongson 3A Notebook was released around 2011-2012
> and had SM712.

"This series of video controller is a legacy from ~1998 and was used on many
classic, prehistoric laptops from 1998-2004" is an objective fact. Even if
they have been used on newer hardware, it doesn't automatically make the original
statement false.

But I agree that the description gives incomplete information, I think this
paragraph should be reworded for clarity.

I would change the description to,

> "sm712fb" is a graphics framebuffer driver for Silicon Motion SM710 (LynxEM),
SM712 (LynxEM+), and SM720 (Lynx3DM, Lynx3DM+, aka. LynxEM4+) series of video
controllers.

> This series of video controllers is a legacy product from ~1998, they are
designed to be primarily used on low-power mobile systems running Windows 95/
98/NT/2000, some examples are HP OmniBook XE2 (2000), Panasonic TOUGHBook 28
(2002), FLORA 210W NL3 (2003), Sony Vaio VGN-U50 (2004) OQO Model 01 (2004).

> After 2004, they continued to be used on some non-x86 systems, including
PowerPC and MIPS. It also saw applications on embedded devices, servers,
industrial computers, embedded devices, where low-power operation and/or only
basic graphics was needed.

> Notably, Lemote YeeLoong 8089, a MIPS laptop based on the Chinese Loongson
[...]

I think it would be enough.

BTW, most Loongson 3A notebooks don't use SM712. I don't know that there are
Loongson 3A notebooks that are still using SM712 graphics chip, do you have one?
Could you tell me its model number?

> > +The first feature is planned to be implemented soon, but the maintainer
> > +does not receive any monetary or hardware support from any company or OEMs,
> > +and he has to purchase a test platform personally. The 1998's hardware
> > +still costs 200 USD+, so don't expected an ETA. If you have a Big-Endian
> > +platform and willing to help testing, please contact the maintainer, thanks!
> 
> I am not sure why will you want to mention about monetary or hardware
> support. Maintainers are supposed to work voluntarily.

I agree, I will reword it.

> > +Other VGA modes, dual-head, or hardware cursor support should be possible to
> > +implement, but parts of the code must be rewritten, and there's little demand
> > +for them on this legacy (retro?) platform, so there's no plan to implement them.
> > +If you have a genuine need for them, please contact the maintainers.
> 
> If there is any need for new features then I think the plan should be to
> make a drm driver.

That's the plan. I will reword.

> There is a MAINTAINERS file to list the maintainers. There is no need to
> add that in documentation.

I see.

Thanks,
Tom Li