public inbox for u-boot@lists.denx.de
 help / color / mirror / Atom feed
From: Jerry Van Baren <gvb.uboot@gmail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] Need input: Use Virtual address in commands; add translation/physical
Date: Wed, 26 Nov 2008 20:39:29 -0500	[thread overview]
Message-ID: <492DFA51.4020003@gmail.com> (raw)
In-Reply-To: <20081126231827.83148834B020@gemini.denx.de>

Wolfgang Denk wrote:
> Dear Jerry,
> 
> In message <492DD314.7070700@gmail.com> you wrote:
>> How would xlat know which direction it is to translate?
> 
> From the argument that is passed to it:
> 
> 	xlat 1234
> or
> 	xlat 0x1234
> 
> are taken as VA's (see discussion about default address
> interpretation), so "xlat" will print the PA.
> 
> 	xlat 1234.p
> or
> 	xlat 0x1234.p
> 
> has a PA as argument, so it prints the VA.
> 
> Multiple arguments (even mixed) might be allowed, too, for example:
> 
> 	xlat 1234 1234.p 5678 5678.p

Ooo, I think the answer to that xlat would make my head hurt.

>> Thoughts:
>>    vtop(virtual) returns physical
>>    ptov(physical) returns virtual
>> or (see below thought on 0v / 0p)
>>    xlat(0p1234) returns virtual
>>    xlat(0v1234) returns physical
>>    xlat(0x1234) returns physical (per convention from snipped discussion)
> 
> Seems too complex for a simple mind like mine ;-)

Ah, we are on the same page here with xlat except I had spurious 
parenthesis (brain was working in C mode, not bash mode) and I used 
0v/0p instead of .v .p.

[snip]

>> Thought:
>>    0v6789ABCD is a virtual address (the value is interpreted as hex)
>>    0p6789ABCD is a physical address
>>
>> Of course "v" and "p" should be accepted in either case.
>>
>> Kinda ugly, but fits into the 0x style conventions.
> 
> I tend to allow for suffixes, i. e. "6789ABCD" or "6789ABCD.v" are
> VAs, while "6789ABCD.p" is a PA.
> 
> To me, that is easier to read.

Agreed.  The .[0-9a-z] suffix is a convention already used by u-boot and 
is much more readable than my 0v and 0p proposal.

[snip]

> Best regards,
> 
> Wolfgang Denk

Thanks,
gvb

  reply	other threads:[~2008-11-27  1:39 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-11-26 22:11 [U-Boot] Need input: Use Virtual address in commands; add translation/physical Becky Bruce
2008-11-26 22:52 ` Jerry Van Baren
2008-11-26 23:18   ` Wolfgang Denk
2008-11-27  1:39     ` Jerry Van Baren [this message]
2008-11-26 23:12 ` Andrew Dyer
2008-11-26 23:22   ` Wolfgang Denk
2008-11-27 17:06     ` Andrew Dyer
2008-11-27 22:15       ` Wolfgang Denk
2008-11-27  6:31 ` Stefan Roese

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=492DFA51.4020003@gmail.com \
    --to=gvb.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