[U-Boot] DDR3 initialization fails after cold boot

Wolfgang Denk wd at denx.de
Wed Jun 16 09:48:09 CEST 2010


Dear prakash bedge,

In message <AANLkTilyOMb3YkQV7o2gmrBuqBwt38nFeZ-Qoq6rJ95N at mail.gmail.com> you wrote:
>
> Also I am seeing that in u-boot timing might be not correct.

Let's say the use of the code is not correct.

> udelay(14000000)  function should generate 14 sec delay but it generates
> delay of only 5 seconds.

udelay() is supposed to provide delays in the microsecond range. It has
never been designed to be used for multi-second delays, which will on
most systems overflow the internal counters.

> I doubt that timing might be issue but I believe that in u-boot udelay
> function is correct.

You are right: the function is correct, but you do not use it
correctly.

> What should be cause behind this cold boot issue for DDr3 initialization?

You don't give ANY information - not even which CPU architecture we
are talking about, or which CPU. Also, you mention some magic
relation to warm or cold booting some Linux system, but without any
details. So what should we comment?

we don;t know anything baout your hardware, nor about your code. It
can be _anything_.

Best regards,

Wolfgang Denk

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