All of lore.kernel.org
 help / color / mirror / Atom feed
From: Bill Pringlemeir <bpringlemeir@nbsps.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 3/4] mtd: nand: add Freescale NFC driver
Date: Thu, 14 Aug 2014 10:26:12 -0400	[thread overview]
Message-ID: <871tsjkv0b.fsf@nbsps.com> (raw)
In-Reply-To: <1407970493.7427.192.camel@snotra.buserror.net> (Scott Wood's message of "Wed, 13 Aug 2014 17:54:53 -0500")

On 13 Aug 2014, scottwood at freescale.com wrote:

> On Wed, 2014-08-13 at 17:44 -0400, Bill Pringlemeir wrote:
>> Regarding "can't know in advance", I think that some of the register
>> values maybe set by the boot rom.  This might make more sense for
>> Linux than U-Boot.  However, after the initial configuration, many do
>> need the 'read/modify/write' as there are many bit fields with
>> different functionality.

> If the register is only modified by software, and not asynchronously
> by hardware, then you could read the value once when the driver
> starts, and cache its value to avoid a reportedly expensive I/O access
> every time you need to modify it.

Yes, that is a good point.  The regmap interface could be used in the
Linux kernel.  I don't see any infrastructure like that in U-Boot?  It
is fairly simple to re-invent as this driver only needs the flat
structure.

Regards,
Bill Pringlemeir.

  reply	other threads:[~2014-08-14 14:26 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-06  8:59 [U-Boot] [PATCH 0/4] arm: vf610: add NAND flash support Stefan Agner
2014-08-06  8:59 ` [U-Boot] [PATCH 1/4] arm: vf610: add NFC pin mux Stefan Agner
2014-08-30 15:14   ` [U-Boot] [U-Boot,1/4] " Tom Rini
2014-08-06  8:59 ` [U-Boot] [PATCH 2/4] arm: vf610: add NFC clock support Stefan Agner
2014-08-30 15:14   ` [U-Boot] [U-Boot,2/4] " Tom Rini
2014-08-06  8:59 ` [U-Boot] [PATCH 3/4] mtd: nand: add Freescale NFC driver Stefan Agner
2014-08-06 23:01   ` Bill Pringlemeir
2014-08-11 22:33   ` Scott Wood
2014-08-12 21:13     ` Stefan Agner
2014-08-12 22:17       ` Scott Wood
2014-08-12 22:58         ` Bill Pringlemeir
2014-08-13  8:13           ` Stefan Agner
2014-08-13 11:20           ` Stefan Agner
2014-08-13 15:14             ` Bill Pringlemeir
2014-08-13 16:27               ` Stefan Agner
2014-08-13 17:11                 ` Bill Pringlemeir
2014-08-13 20:32             ` Scott Wood
2014-08-13 20:41           ` Scott Wood
2014-08-13 21:44             ` Bill Pringlemeir
2014-08-13 22:54               ` Scott Wood
2014-08-14 14:26                 ` Bill Pringlemeir [this message]
2014-08-06  8:59 ` [U-Boot] [PATCH 4/4] arm: vf610: add NAND support for vf610twr Stefan Agner

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=871tsjkv0b.fsf@nbsps.com \
    --to=bpringlemeir@nbsps.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 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.