From: qwx@sciops.net
To: 9front@9front.org
Subject: Re: [9front] displayport thinkpad x230 external monitor black screen
Date: Mon, 17 Apr 2023 09:53:28 +0200 [thread overview]
Message-ID: <B6C688F821B1046148DC9BD333F8742A@wopr.sciops.net> (raw)
In-Reply-To: <ZDXR1gTC9vRlbN42@simple-cc.org>
On Sun Apr 9 08:58:34 +0200 2023, unobe@cpan.org wrote:
> I figured out the problem--the DisplayPort link training needed to be
> implemented more fully. I didn't know really much at all about
> DisplayPort; that has changed. I've attached a patch that implements
> pattern 1 & 2 training for HBR, along with fixing a couple other minor
> things I came across.[1]
>
> I'd be curious if the patch works for you, igor and qwx. I don't see
> why it wouldn't, but who knows. Reader be warned: I'm not a C
> programmer, so I'm sure there's much that can be improved upon.
Alright, sorry for taking so long. I'm going to test the patch on a
w500 and a w520 (resp. gm965 and sandybridge, iirc) as soon as I'm
able. I don't actually have any remarks on what you did itself, looks
good; I only have one comment on style: please be consistent with the
rest of the code, mostly add spacing around operators (for example the
shifts), and remove useless parenthesis (less important). The only
other thing:
> + while(--i){
> + if(memcmp(tmp+i, magic, 8) == 0){
> + trace("magic begins at index %d, shifting\n", i);
> + memcpy(buf, tmp+i, 256-i);
> + memcpy(buf+(256-i), tmp, i);
> + i = 1;
> + }
> + }
Why not just a `break;' there? Anyway, not important.
> To test my patch, I defined this test function to ensure I could get
> my working display back. I didn't need to add anything to /lib/vgadb.
>
> fn lg {
> @ {
> rfork n; aux/realemu; cd /sys/src/cmd/aux/vga; mk; /sys/src/cmd/aux/vga/6.out -v -V -m igfx -l 2560x1080; sleep 5; aux/vga -m igfx -l 1366x768
> }
> }
You don't need to run aux/realemu unless you will use vesa, which you
don't. Also, in practice, do you still have to run aux/vga twice, or
is that just for testing? Do you need this function at all now, that
is, does it not work by just having `monitor=auto' in plan9.ini?
@k0ga:
On Tue Apr 11 23:30:37 +0200 2023, k0ga@shike2.com wrote:
> I have one DP monitor here (qwx do you remember that we used it for our tests
> in the last hackathon ;) ?. I can try it but not in this week.
Yes, please do :) In fact, I bid anyone who has igfx to please check
for a regression :) Unfortunately, I don't have access for a few weeks
to other machines. For reference, anything up to and including
broadwell (x250 generation) that has its pci device id in /lib/vgadb
and in /sys/src/cmd/aux/vga/igfx.c should still work with the
integrated screen, and now possibly with an external screen through DP
(not hdmi).
Thanks again!
Cheers,
qwx
next prev parent reply other threads:[~2023-04-17 7:55 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-09 21:26 qwx
2023-04-09 22:42 ` sirjofri
2023-04-11 21:33 ` Steve Simon
2023-04-12 22:13 ` unobe
2023-04-11 21:32 ` Roberto E. Vargas Caballero
2023-04-17 7:53 ` qwx [this message]
2023-04-19 20:50 ` unobe
2023-04-20 23:40 ` qwx
2023-04-24 18:52 ` qwx
2023-04-26 3:32 ` unobe
2023-04-30 3:12 ` qwx
-- strict thread matches above, loose matches on Subject: below --
2023-03-30 17:37 Romano
2023-03-30 17:47 ` Stanley Lieber
2023-04-03 22:27 ` qwx
2023-04-04 22:39 ` igor
2023-04-04 22:43 ` sl
2023-04-05 7:01 ` qwx
2023-04-09 6:59 ` unobe
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=B6C688F821B1046148DC9BD333F8742A@wopr.sciops.net \
--to=qwx@sciops.net \
--cc=9front@9front.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;
as well as URLs for NNTP newsgroup(s).