All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stefan Roese <sr@denx.de>
To: u-boot@lists.denx.de
Subject: [U-Boot-Users] ppc4xx: Initializing GPIO0_OR and GPIO0_ODR
Date: Fri, 7 Apr 2006 03:51:05 +0200	[thread overview]
Message-ID: <200604070351.06318.sr@denx.de> (raw)
In-Reply-To: <44359D8B.9030006@orkun.us>

Hi Tolunay,

On Friday, 7. April 2006 01:00, Tolunay Orkun wrote:
> On a PPC405EP based boards, U-Boot is initializing below registers to
> select between primary and alternate functions of the GPIO pins (e.g.
> GPIO10 vs CS1) using the CFG_CPIO0_... macros defined in the board
> config file.
>
> GPIO0_TCR, GPIO0_OSRH, GPIO0_OSRL, GPIO0_TSRH, GPIO0_TSRL, GPIO0_ISR1H,
> GPIO0_ ISR1L
>
> This much is sufficient for alternate function programming. However, if
> a the GPIO pin is actually used as GPIO output pin, the initial signal
> level presented happens to be "0" which may not be appropriate for some
> implementations.
>
> I propose to introduce CFG_GPIO0_OR and CFG_CPIO0_ODR macros that could
> be defined in the appropriate board config file and initialize GPIO0_OR
> and GPIO0_ODR before GPIO0_TCR. If these macros are undefined the
> existing code behavior could be maintained so the additional macros
> would not break any existing board or add any additional code.

Sounds good to me.

> I will be introducing a patch to take care of this but I wanted to get
> feedback first.

Please send your patch.

Best regards,
Stefan

PS: Did you happen to take a look at the recent changes I made to the 
cfi_flash driver? Now the Intel "legacy lock/unlocking" is supported. Please 
let me know if you see any problems with these changes (I could only test on 
J3 FLASH's with legacy unlocking).

      reply	other threads:[~2006-04-07  1:51 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-04-06 23:00 [U-Boot-Users] ppc4xx: Initializing GPIO0_OR and GPIO0_ODR Tolunay Orkun
2006-04-07  1:51 ` Stefan Roese [this message]

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=200604070351.06318.sr@denx.de \
    --to=sr@denx.de \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.