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* RE: RedBoot patches regarding redboot_getc_terminate
@ 2006-05-20  0:08 Andrew Dyer
  0 siblings, 0 replies; 10+ messages in thread
From: Andrew Dyer @ 2006-05-20  0:08 UTC (permalink / raw)
  To: Doyle, Patrick, David Vrabel, Andrew Lunn; +Cc: Doyle, Patrick, ecos-devel

> Perhaps the 'tftp_stream_terminate()' function should be modified to issue
> the "Remaining file contents not required" message in the case of a normal
> termination.

That sounds fine to me, but I can't test as I would have to pull
the old target board out of mothballs (ie actually FIND it) and
resurrect a cygwin server to do any testing.  We haven't done
much redboot/ecos stuff for a long time.

^ permalink raw reply	[flat|nested] 10+ messages in thread
* RE: RedBoot patches regarding redboot_getc_terminate
@ 2006-05-18 16:59 Doyle, Patrick
  0 siblings, 0 replies; 10+ messages in thread
From: Doyle, Patrick @ 2006-05-18 16:59 UTC (permalink / raw)
  To: 'David Vrabel', Andrew Lunn
  Cc: Doyle, Patrick, 'ecos-devel@sources.redhat.com',
	'Andrew Dyer'

> -----Original Message-----
> From: David Vrabel [mailto:dvrabel@arcom.com] 
> Sent: Thursday, May 18, 2006 11:55 AM
> To: Andrew Lunn
> Cc: Doyle, Patrick; 'ecos-devel@sources.redhat.com'; 'Andrew Dyer'
> Subject: Re: RedBoot patches regarding redboot_getc_terminate
> 
> 
> Andrew Lunn wrote:
> >> I'm not entirely happy with the fix. It terminates the 
> download when all
> >> the relevant bits of the ELF have been transferred. The causes the
> >> sender to think that the file transfer has failed which causes some
> >> customer confusion.
> > 
> > It is possible to include a text string in the error message. 
> > 
> > http://www.faqs.org/rfcs/rfc1350.html, figure 5-4. 
> > 
> > So maybe a message like "Remaining file contents not required" would
> > prevent confusion. This assumes the lame tftp servers actually display
> > the message to the user.
> 
> This would take care of the TFTP transfers.  But what about 
> the Y-modem transfers?

Well, 'retboot_getc_terminate(false)' has always worked for me in the past,
and continues to work for me now that I've put it back in.

Perhaps the 'tftp_stream_terminate()' function should be modified to issue
the "Remaining file contents not required" message in the case of a normal
termination.

> 
> >> I think a better solution would be for the downloader to continue to
> >> transfer the remaining portions of the ELF image and just throw them
away."
> > 
> > This can be a lot of data, eg the complete debug symbol table if the
> > image has been compiled -g. I would not really be in favor of that.
> 
> Agreed.  Although I think this is what RedBoot used to do for Y-modem
> transfers.

Actually, as confusing as this is to me, this is what it _still_ does!  I'm
pretty sure I remember the behavior you describe, but I'm darn'd if I can
see it in the code (nor in practice).

So if I submit a modified patch that restores the call to
'redboot_getc_terminate()' to its original (pre Andrew Dyer) state and
modify 'tftp_stream_terminate()' to issue different strings based on normal
vs. abnormal termination conditions, is there anybody who can test the TFTP
changes?

--wpd

^ permalink raw reply	[flat|nested] 10+ messages in thread
* RE: RedBoot patches regarding redboot_getc_terminate
@ 2006-05-18 13:40 Doyle, Patrick
  2006-05-18 13:54 ` Andrew Lunn
  2006-05-18 15:00 ` David Vrabel
  0 siblings, 2 replies; 10+ messages in thread
From: Doyle, Patrick @ 2006-05-18 13:40 UTC (permalink / raw)
  To: 'Andrew Lunn'
  Cc: 'ecos-devel@sources.redhat.com', 'Andrew Dyer'

> 
> What happens to TFTP transfers with your change? Are they terminated
> gracefully? Or do they hang around until the server times out and
> kills them?
> 
>       Andrew
> 
Unfortunately, I don't have any means to check that.  Which is why I brought
it up as a topic for discussion.  Then I realized that it would be easier to
discuss if somebody who _did_ have a means to check that checked that, which
led to me posting the patch :-)

IIRC, a TFTP server will keep spewing out packets until it has sent the
whole file, and will retry and retransmit if the client stops responding.
So, it guess it depends on what the TFTP transport stream (implemented in
code somewhere in RedBoot) does when it gets a "terminate" call that isn't
an abort...

Hmmm... looking at the code, I see something that looks like:

if (abort)
  tftp_error_ack(...)
else
  tftp_ack(...)

which looks to me like TFTP folks would be getting some sort of similar
error message for TFTP transfers.

I wonder why I'm the only one whose noticed this?  (he asks in a plaintive,
"why do these things always happen to me" voice)

--wpd

^ permalink raw reply	[flat|nested] 10+ messages in thread
* RE: RedBoot patches regarding redboot_getc_terminate
@ 2006-05-18 13:32 Doyle, Patrick
  0 siblings, 0 replies; 10+ messages in thread
From: Doyle, Patrick @ 2006-05-18 13:32 UTC (permalink / raw)
  To: 'ecos-patches@ecos.sourceware.org'
  Cc: 'ecos-devel@ecos.sourceware.org'

[-- Attachment #1: Type: text/plain, Size: 106 bytes --]

Ahh what the heck... here's the patch anyway, just to add a little more meat
to the discussion...

--wpd


[-- Attachment #2: redboot-load.patch --]
[-- Type: application/octet-stream, Size: 1578 bytes --]

Index: ChangeLog
===================================================================
RCS file: /cvs/ecos/ecos/packages/redboot/current/ChangeLog,v
retrieving revision 1.237
diff -u -r1.237 ChangeLog
--- ChangeLog	30 Jan 2006 21:04:04 -0000	1.237
+++ ChangeLog	18 May 2006 13:25:01 -0000
@@ -1,3 +1,8 @@
+2006-05-18  Patrick Doyle  <wpd@dtccom.com>
+
+	* src/load.c (load_elf_image): Terminate ELF transfers gracefully
+	after reading all of the sections required by RedBoot.
+
 2005-11-23  Peter Korsgaard  <peter.korsgaard@barco.com>
 
 	* src/gunzip.c (do_gunzip): Fixed diag_printf format string warnings.
Index: src/load.c
===================================================================
RCS file: /cvs/ecos/ecos/packages/redboot/current/src/load.c,v
retrieving revision 1.45
diff -u -r1.45 load.c
--- src/load.c	9 Sep 2005 13:26:03 -0000	1.45
+++ src/load.c	18 May 2006 13:25:01 -0000
@@ -430,10 +430,9 @@
         entry_address = ehdr.e_entry;
     }
 
-    // nak everything to stop the transfer, since redboot
-    // usually doesn't read all the way to the end of the
-    // elf files.
-    redboot_getc_terminate(true);
+    // Terminate the transfer gracefully at this point, since redboot
+    // usually doesn't read all the way to the end of the elf files.
+    redboot_getc_terminate(false);
     if (addr_offset) diag_printf("Address offset = %p\n", (void *)addr_offset);
     diag_printf("Entry point: %p, address range: %p-%p\n", 
                 (void*)entry_address, (void *)load_address, (void *)load_address_end);

^ permalink raw reply	[flat|nested] 10+ messages in thread
* RedBoot patches regarding redboot_getc_terminate
@ 2006-05-18 13:18 Doyle, Patrick
  2006-05-18 13:26 ` Andrew Lunn
  0 siblings, 1 reply; 10+ messages in thread
From: Doyle, Patrick @ 2006-05-18 13:18 UTC (permalink / raw)
  To: 'ecos-devel@sources.redhat.com'; +Cc: 'Andrew Dyer'

Sometime since September of 2005, we updated our local eCos repository,
which includes Andrew Dyer's RedBoot patches to call
'redboot_getc_terminate()' in various error scenarios.  Since that time, we
have observed that anytime we use YMODEM to download code to our boards, it
terminates with an error message.

I hate training myself to ignore error messages... it always comes back to
haunt me.

So, I looked into this, and I see in 'load_elf_image()', near line 455 of
"load.c", there is a call to 'redboot_getc_terminate()' with an an argument
of 'true', indicating that the data transfer should be aborted.  I changed
the abort flag back to 'false', and things have returned to normal for us.

However, before I submit a formal patch undoing the work that Andrew did
(which had to do with terminating TFTP transfers gracefully), I thought I
would check in with folks, Andrew especially.

What do folks think?  Should I generate the one line patch (along with the 5
line ChangeLog entry)?

--wpd


Patrick Doyle
Manager, Digital Systems Group
DTC Communications, Inc.
Phone: (603) 546-2179
Fax: (603) 880-6965
Email: wpd@dtccom.com

 

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^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2006-05-20  0:08 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2006-05-20  0:08 RedBoot patches regarding redboot_getc_terminate Andrew Dyer
  -- strict thread matches above, loose matches on Subject: below --
2006-05-18 16:59 Doyle, Patrick
2006-05-18 13:40 Doyle, Patrick
2006-05-18 13:54 ` Andrew Lunn
2006-05-18 15:00 ` David Vrabel
2006-05-18 15:14   ` Andrew Lunn
2006-05-18 15:59     ` David Vrabel
2006-05-18 13:32 Doyle, Patrick
2006-05-18 13:18 Doyle, Patrick
2006-05-18 13:26 ` Andrew Lunn

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