From: Mike Frysinger <vapier@gentoo.org>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 01/21] Define new system_restart() and emergency_restart()
Date: Mon, 7 Mar 2011 21:45:55 -0500 [thread overview]
Message-ID: <201103072145.56902.vapier@gentoo.org> (raw)
In-Reply-To: <AANLkTimHMjw-otpfkZX6iMaq6MVzG28RWd8rX2EhYLwo@mail.gmail.com>
On Monday, March 07, 2011 18:09:25 Graeme Russ wrote:
> On Tue, Mar 8, 2011 at 9:10 AM, Mike Frysinger <vapier@gentoo.org> wrote:
> > On Monday, March 07, 2011 16:56:31 Moffett, Kyle D wrote:
> >> On Mar 07, 2011, at 16:40, Mike Frysinger wrote:
> >> > On Monday, March 07, 2011 12:37:22 Kyle Moffett wrote:
> >> >> + udelay(50000);
> >> >
> >> > this doesnt sit well with me. i dont see why this matters ... we dont
> >> > have any delays today, and i dont think we should introduce any.
> >>
> >> Actually, several architectures had a printf()+udelay() already. (i386
> >> and ARM, IIRC). Since I was moving the printf() to common code I
> >> figured I'd better move the udelay() as well.
> >>
> >> I believe they had comments to the effect of "This udelay() prevents
> >> garbage on the serial console while rebooting", I would guess because it
> >> gives the FIFO time to finish flushing.
> >
> > Blackfin specifically does not do this. personally, a half baked uart
> > char is preferable to a (imo) useless hardcoded delay. i wonder if they
> > picked a number that seems to work, or actually calculated it based on
> > the slowest baud times the deepest fifo times the extra bits
> > (parity/stop/etc...). i'd suspect the former which means this is even
> > dumber.
> >
> >> I can move it back to the individual architectures if you'd like.
> >
> > if we cant agree to simply punt it, then yes, please do. or make it a
> > config option so board porters can opt out, and default it to on for
> > only the existing arches.
>
> Is there any way we could detect that the UART FIFO is empty and wait on
> that condition (with a timeout in case the FIFO is never emptied)?
that would require extending the serial API to add a new func, have each
serial driver implement (i'm pretty sure most serial devices out there expose
a bit to poll such status), and then having the code call it. i'm not saying
it cant be done, just outlining the requirements.
although i vaguely recall that Wolfgang is against this sort of thing since it
kind of goes against the KISS principle ...
-mike
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 836 bytes
Desc: This is a digitally signed message part.
Url : http://lists.denx.de/pipermail/u-boot/attachments/20110307/518432e3/attachment.pgp
next prev parent reply other threads:[~2011-03-08 2:45 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-07 17:37 [U-Boot] [PATCH 0/21] Generic cross-architecture system restart support Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 01/21] Define new system_restart() and emergency_restart() Kyle Moffett
2011-03-07 21:40 ` Mike Frysinger
2011-03-07 21:56 ` Moffett, Kyle D
2011-03-07 22:10 ` Mike Frysinger
2011-03-07 23:09 ` Graeme Russ
2011-03-08 2:45 ` Mike Frysinger [this message]
2011-03-13 19:24 ` Wolfgang Denk
2011-03-14 16:23 ` Moffett, Kyle D
2011-03-14 18:59 ` Wolfgang Denk
2011-03-14 19:52 ` Moffett, Kyle D
2011-03-14 20:38 ` Wolfgang Denk
2011-03-14 21:20 ` Moffett, Kyle D
2011-03-14 22:01 ` Wolfgang Denk
2011-03-21 11:43 ` Graeme Russ
2011-03-21 12:00 ` Wolfgang Denk
2011-03-22 12:05 ` Graeme Russ
2011-03-22 13:28 ` Wolfgang Denk
2011-03-23 0:19 ` Graeme Russ
2011-04-11 18:31 ` Wolfgang Denk
2011-03-07 17:37 ` [U-Boot] [PATCH 02/21] Replace do_reset() calls with {system, emergency}_restart() Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 03/21] arm: Call "panic()" instead of "hang()" for div-by-zero Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 04/21] arm: Replace unnecessary bad_mode() with panic() Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 05/21] arm: cpux9k2: Remove unnecessary XF_do_reset assignment Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 06/21] arm: Rename nonstandard board_reset() as at91_board_reset() Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 07/21] arm: Generic system restart support Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 08/21] avr32: " Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 09/21] blackfin: Replace "bfin_reset_or_hang()" with "panic()" Kyle Moffett
2011-03-07 21:44 ` Mike Frysinger
2011-03-07 17:37 ` [U-Boot] [PATCH 10/21] blackfin: Generic system restart support Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 11/21] i386: " Kyle Moffett
2011-03-07 21:54 ` Graeme Russ
2011-03-07 22:06 ` Moffett, Kyle D
2011-03-07 22:26 ` Graeme Russ
2011-03-07 22:57 ` Moffett, Kyle D
2011-03-07 23:06 ` Graeme Russ
2011-03-07 17:37 ` [U-Boot] [PATCH 12/21] m68k: " Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 13/21] microblaze: " Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 14/21] mips: " Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 15/21] nios2: " Kyle Moffett
2011-03-09 0:13 ` Scott McNutt
2011-03-09 0:42 ` Moffett, Kyle D
2011-03-09 1:33 ` Scott McNutt
2011-03-07 17:37 ` [U-Boot] [PATCH 16/21] powerpc: " Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 17/21] sh: Unify duplicate reset code Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 18/21] sh: Generic system restart support Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 19/21] sparc: Unify duplicate reset code Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 20/21] sparc: Generic system restart support Kyle Moffett
2011-03-07 17:37 ` [U-Boot] [PATCH 21/21] Remove legacy do_reset() function Kyle Moffett
2011-03-07 21:55 ` Graeme Russ
2011-03-07 23:00 ` Moffett, Kyle D
2011-03-07 23:03 ` Graeme Russ
2011-03-07 21:44 ` [U-Boot] [PATCH 0/21] Generic cross-architecture system restart support Graeme Russ
2011-03-13 19:16 ` Wolfgang Denk
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=201103072145.56902.vapier@gentoo.org \
--to=vapier@gentoo.org \
--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