public inbox for u-boot@lists.denx.de
 help / color / mirror / Atom feed
From: Reinhard Meyer <u-boot@emk-elektronik.de>
To: u-boot@lists.denx.de
Subject: [U-Boot] SPI flash protection
Date: Mon, 31 Jan 2011 08:17:36 +0100	[thread overview]
Message-ID: <4D466210.7090906@emk-elektronik.de> (raw)
In-Reply-To: <4D465C4B.3020201@free.fr>

Dear Albert ARIBAUD, Simon Guinot,
>
>>>> Here is the protect area map for a MX25L4005A 4Mb flash:
>>>>
>>>>     bit  2 1 0 | protect level
>>>>    ____________|_______________
>>>>          0 0 0 | none
>>>>          0 0 1 | block 7
>>>>          0 1 0 | block 6-7
>>>>          0 1 1 | block 4-7
>>>>          1 * * | all
>> Block size is 64KB. The compiled U-Boot image is about 220KB and
>> environment is 4KB. So, 4 blocks are required for U-Boot.

I don't know your particular hardware, but is not u-boot (or the
initial bootloader if there is any) fetched from the *beginning*
of the flash?

If so, you would have to *hardware* protect the *entire* flash.

In this case, a *software* protection mechanism like for NOR flash
would be a better choice.

Best Regards,
Reinhard

  reply	other threads:[~2011-01-31  7:17 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-29 17:00 [U-Boot] SPI flash protection Simon Guinot
2011-01-30  9:36 ` Albert ARIBAUD
2011-01-30 14:56   ` Simon Guinot
2011-01-30 17:19     ` Albert ARIBAUD
2011-01-31  0:31       ` Simon Guinot
2011-01-31  6:52         ` Albert ARIBAUD
2011-01-31  7:17           ` Reinhard Meyer [this message]
2011-02-01  9:09             ` Simon Guinot
2011-02-01 12:26               ` Albert ARIBAUD
2011-02-15  8:42 ` Mike Frysinger

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=4D466210.7090906@emk-elektronik.de \
    --to=u-boot@emk-elektronik.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox