public inbox for u-boot@lists.denx.de
 help / color / mirror / Atom feed
From: hacklu <hacklu.uboot@gmail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] how to understand "uboot is 32bit program even it is in the 64bit mips"
Date: Wed, 22 Jun 2011 10:07:05 +0800	[thread overview]
Message-ID: <201106221006548156815@gmail.com> (raw)

  I have a 64bit cnMips borad.In the mail list archives,it says  "uboot is 32bit,even in the 64bit cpu."
but how to understand that?
I have a guess,is the 64bit cpu support a 32bit-mode,then when does it switch to 64bit-mode to load 64-bit linux?

btw,I have an other question,according to  <see mips run linux>,linux run in the _xkseg_ segment. so the first two bit virtual address in kernel space must be 11,
like 11xx xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx (64bit).
but when I printf a variable' address in a foo driver,is say 0xa80000041c2ea180. not start of _11_.
the memory mapping mode has feazed me for _long_ _long_time.

Dear Wolfgang(or someone else who can anwser me),thanks 
 				
--------------
hacklu
2011-06-22

             reply	other threads:[~2011-06-22  2:07 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-22  2:07 hacklu [this message]
2011-06-22  5:10 ` [U-Boot] how to understand "uboot is 32bit program even it is in the 64bit mips" Aaron Williams
2011-06-22  7:02 ` [U-Boot] how to understand "uboot is 32bit program even it isin " hacklu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=201106221006548156815@gmail.com \
    --to=hacklu.uboot@gmail.com \
    --cc=u-boot@lists.denx.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox