mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Robert Jarzmik <robert.jarzmik@free.fr>
To: barebox@lists.infradead.org
Subject: Barebox newbie questions : arch/arm/{plat,mach} split and interrupts
Date: Sun, 13 Nov 2011 19:29:32 +0100	[thread overview]
Message-ID: <8739drj2pf.fsf@free.fr> (raw)

Hi,

As I'm a bit new to barebone, and after reading a bit the code for the ARM
architectures, I have questions :

 (1) Why is there not anywhere a arch/arm/plat-xxx ?
     My understanding is that normally, platform generic code (like gpio
     handling for XScale processors) should go there.
     The machine specific code (ie. PXA27x, PXA25x, etc ...) would still go to
     arch/arm/mach-pxa.

 (2) In arch/arm, I understand that interruptions are never used (do_irq()
     implementation is quite clear about that). Is that a design decision and
     why ?
     If so, I suppose that active polling for each device is required. Am I
     right here ?

 (3) MMU: one can enable or not the MMU. AFAIR, the MMU is required to enable
     both I-Cache and D-Cache on ARM achitectures. Are there any other obvious
     advantages I'm missing in the case of a bootloader ?

 (4) Is it possible to have 2 outputs as result of compilation of barebox for a
     board ?
     Let me be clearer. My board, mioa701, has a disk-on-chip on which it can
     boot. Barebox will be the SPL (written from barebox.bin). The IPL, which is
     limited to 2048 bytes, will only initialize RAM, GPIOs, and load the
     SPL. Is there a way for me to add the generation of a 'mioa701_ipl.bin' out
     of a 'mioa701_ipl.S' ?

Cheers.

-- 
Robert

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

             reply	other threads:[~2011-11-13 18:29 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-11-13 18:29 Robert Jarzmik [this message]
2011-11-14  8:37 ` Sascha Hauer
2011-11-14  9:34 ` Barebox newbie questions : arch/arm/{plat, mach} " Antony Pavlov

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=8739drj2pf.fsf@free.fr \
    --to=robert.jarzmik@free.fr \
    --cc=barebox@lists.infradead.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