[U-Boot] [RESEND 2/2] mmc:fix Call mmc_init() when executing mmc_get_dev()

Lukasz Majewski l.majewski at samsung.com
Fri Apr 20 09:09:52 CEST 2012


Hi, Lei

> I'm concerning with this adding init here.
> Since not every platform mount with emmc as boot device, and what they
> need is booting fast. 

If I remember correctly, u-boot policy is to not initialize the mmc
until it is needed (i.e. command is executed).
So the extra init won't be executed until fatls or mmc is executed.

> If you order them to initialize all mmc/sd at
> mmc register stage, this adding booting time may not be the one they
> want to see.

I think that booting time will not increase, because in the mmc_init()
there is a check:

	if (mmc->has_init)
		return 0;

To prevent multiple register level initialization.

The execution time increase is boiled down to executing a
few instructions (when mmc->has_init is set).


-- 
Best regards,

Lukasz Majewski

Samsung Poland R&D Center
Platform Group


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