From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jerry Van Baren <gerald.vanbaren@smiths-aerospace.com>
Date: Wed, 08 Nov 2006 10:56:44 -0500
Subject: [U-Boot-Users] why need disable icache
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Jackson wrote:
> Hi, all
> I have been confused by cache recently.
> 1. why need we disable icache and dcache at the beginning of the u-boot 
> code?

In case the system does a soft reset: a soft reset generally leaves
caches enabled.

> 2. when can we enable them ?

Simple question, complex answer.  The simple answer is after the CPU and
your hardware are initialized properly such that enabling caches doesn't
cause it to crash.  The details is where it gets complex because it
depends on the processor you are using, the hardware you have, and how
you are using both the processor and the hardware.  IOW, only you can
answer the question.

> Thank you for the help.
> 
> Best regards
> Jackson

gvb