[U-Boot] [PATCH v2] mmc: omap: timeout counter fix

[Wolfgang Denk]

Dear Reinhard Meyer,

In message <4CC66ECA.9000106 at emk-elektronik.de> you wrote:
>
> Agreed here. People are invited to dig through u-boot and find all
> those places.

You know the ones you added best :-)

>  > int main(void)
>  > {
>  > 	unsigned int time = 0xFFFFFFF0;
>  > 	unsigned int delay = 0x20;
>  > 	unsigned int start;
> 
> You are wrong here, because you take it out of context.

I am not wrong. Feel free to replace "unsigned int" by "unsigned long
long", and 0xFFFFFFF0 by 0xFFFFFFFFFFFFFFF0ULL, and the "%X" by "%llX".

> My "demo" is using the (declared as) 64 bit function get_ticks().
> I mentioned above that this function MUST be truly returning 64
> bits worth of (incrementing) value to make any version work.

What's the difference?  It is inherently wrong to believe an overflow
would never occur just because the precision of a number is "long
enough". Remeber y2k issues. Remember the time overflog for UNIX
systems in 2038, etc. etc.

> If get_ticks() just returns a 32 bit counter value neither method will work
> reliably. Just check all implementations that this function is implemented
> correctly.

No, the code is still WRONG. It'ss just that the problem is less
likely to hit.

BTW - who says the timer starts counting at 0 ?

Best regards,

Wolfgang Denk

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