linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: "Omanakuttan" <omanakuttan@tataelxsi.co.in>
To: linuxppc-embedded@lists.linuxppc.org
Subject: accessing immap_t * variable in mpc8260
Date: Thu, 13 Mar 2003 20:54:51 +0530	[thread overview]
Message-ID: <3E70A2C3.8090305@tataelxsi.co.in> (raw)


Hi,
We are writing existing drivers for mpc8260 FCC and writing new ones for
MCC. we are unable to small (may be foolish) problem of accessing immap
address registers.

In FCC code, eldk/ppc_82xx/usr/src/linux/arch/ppc/8260_io/fcc_enet.c,
immap_t * immap is simply typecasted to IMAP_ADDR, which is
((uint)0xf0000000).
Now, after assigning this physical address, fcc_enet code continues the
immap_t variable without doing any __va macro.

I am confused at this point, that how can kernel code access a physical
address as if it were virtual address ? how does the page frame -> page
conversion (and vice versa) happens on this front?

Thanks and regards,
Om.


** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

             reply	other threads:[~2003-03-13 15:24 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-03-13 15:24 Omanakuttan [this message]
2003-03-13 15:30 ` accessing immap_t * variable in mpc8260 Dan Malek
2003-03-13 22:15 ` Paul Mackerras
2003-03-14  5:36   ` Omanakuttan

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=3E70A2C3.8090305@tataelxsi.co.in \
    --to=omanakuttan@tataelxsi.co.in \
    --cc=linuxppc-embedded@lists.linuxppc.org \
    /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;
as well as URLs for NNTP newsgroup(s).