Devicetree
 help / color / mirror / Atom feed
From: Shawn Guo <shawn.guo-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
To: Nicolas Pitre <nico-vtqb6HGKxmzR7s880joybQ@public.gmane.org>
Cc: Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>,
	devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org,
	linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Subject: Re: [PATCH 4/4] ARM: zImage: allow supplementing appended DTB with traditional ATAG data
Date: Tue, 21 Jun 2011 15:00:59 +0800	[thread overview]
Message-ID: <20110621070058.GA9228@S2101-09.ap.freescale.net> (raw)
In-Reply-To: <1308632955-11070-5-git-send-email-nico-vtqb6HGKxmzR7s880joybQ@public.gmane.org>

On Tue, Jun 21, 2011 at 01:09:15AM -0400, Nicolas Pitre wrote:
> From: Nicolas Pitre <nicolas.pitre-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> 
> Some old bootloaders can't be updated to a device tree capable one,
> yet they provide ATAGs with memory configuration, the ramdisk address,
> the kernel cmdline string, etc.  To allow a device tree enabled
> kernel to be used with such bootloaders, it is necessary to convert those
> ATAGs into FDT properties and fold them into the DTB appended to zImage.
> 
> Currently the following ATAGs are converted:
> 
> 	ATAG_CMDLINE
> 	ATAG_MEM (up to 8 memory regions)
> 	ATAG_INITRD2
> 
> If the corresponding information already exists in the appended DTB, it
> is replaced, otherwise the required node is created to hold it.
> 
> The code looks for ATAGs at the location pointed by the value of r2 upon
> entry into the zImage code.  If no ATAGs are found there, an attempt at
> finding ATAGs at the typical 0x100 offset from start of RAM is made.
> Otherwise the DTB is left unchanged.
> 
> Thisstarted from an older patch from John Bonesio <bones-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>,
> with contributions from David Brown <davidb-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>.
> 
> Signed-off-by: Nicolas Pitre <nicolas.pitre-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> ---

With this patch applied, I saw nothing coming from kernel on imx51
babbage serial port.

-- 
Regards,
Shawn

  parent reply	other threads:[~2011-06-21  7:00 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-21  5:09 [PATCH 0/4] allow DTB to be appended to the ARM zImage with ATAG conversion Nicolas Pitre
     [not found] ` <1308632955-11070-1-git-send-email-nico-vtqb6HGKxmzR7s880joybQ@public.gmane.org>
2011-06-21  5:09   ` [PATCH 1/4] ARM: zImage: ensure it is always a multiple of 64 bits in size Nicolas Pitre
2011-06-21  5:09   ` [PATCH 2/4] ARM: zImage: Allow the appending of a device tree binary Nicolas Pitre
2011-06-21  5:09   ` [PATCH 3/4] ARM: zImage: make sure appended DTB doesn't get overwritten by kernel .bss Nicolas Pitre
2011-06-21  5:09   ` [PATCH 4/4] ARM: zImage: allow supplementing appended DTB with traditional ATAG data Nicolas Pitre
     [not found]     ` <1308632955-11070-5-git-send-email-nico-vtqb6HGKxmzR7s880joybQ@public.gmane.org>
2011-06-21  7:00       ` Shawn Guo [this message]
2011-06-21 17:32         ` David Brown
2011-06-21 22:58       ` David Brown
2011-06-21 23:13         ` David Brown
     [not found]           ` <8ya7h8edbhc.fsf-AOX6H5vLt3Uj8izMo0bVsAC/G2K4zDHf@public.gmane.org>
2011-06-21 23:22             ` Warner Losh
2011-06-21 23:35             ` Nicolas Pitre
2011-06-21 21:59   ` [PATCH 0/4] allow DTB to be appended to the ARM zImage with ATAG conversion David Brown

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=20110621070058.GA9228@S2101-09.ap.freescale.net \
    --to=shawn.guo-kzfg59tc24xl57midrcfdg@public.gmane.org \
    --cc=devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org \
    --cc=linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org \
    --cc=nico-vtqb6HGKxmzR7s880joybQ@public.gmane.org \
    --cc=tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.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