[Openec] SPI Flash Fast Read, 46% speed increase

[Richard A. Smith]

Frieder Ferlemann wrote:

> The quicker EC translates into powersavings if the XO waits
> for the EC and if the SPI clock is properly gated (CLKCFG bit 0,
> openec will take advantage of this).

Can I just hit this bit somewhere on the boot sequence or does it have 
to be synced with something?

Not sure about the power savings though because the EC never sleeps in 
the current design.

The other gotcha is that most of the delays in the laptop EC code are 
based on loop time.  Changing the loop time may have some interesting 
results...

> I cannot currently oversee what that speed increase would mean
> for the XO.
> Yet if a quick SPI is among the options (it would not help
> if f.e. a quick SPI had ElectroMagnetic Interference problems)
> and it's not too late then one could go for it?)

It sounds great but if its out of spec for the spansion then I don't 
think we can ever use it in production unless spansion tells me its OK. 
  Thats the type of thing you can run on thousand's of units ok and then 
one batch of chips that are on the slower side of the typical screw you. 


-- 
Richard Smith  <richard at laptop.org>
One Laptop Per Child