linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Scott Wood <swood@redhat.com>
To: David Lamparter <equinox@diac24.net>, linuxppc-dev@lists.ozlabs.org
Cc: Scott Wood <oss@buserror.net>, York Sun <york.sun@nxp.com>
Subject: Re: [PATCH ppc-next] powerpc/fsl-booke: don't load early TLB at once
Date: Thu, 20 Sep 2018 19:31:33 -0500	[thread overview]
Message-ID: <1537489893.7689.38.camel@redhat.com> (raw)
In-Reply-To: <20180920224856.GJ487685@eidolon.nox.tf>

On Fri, 2018-09-21 at 00:48 +0200, David Lamparter wrote:
> This is a *partial* revert of "powerpc/85xx: Load all early TLB entries
> at once" (d9e1831a420267a7ced708bb259d65b0a3c0344d.)
> 
> My dusty old P4080DS just completely fails to boot (no output at all)
> without this revert.  I have no clue what's going on here, I just
> bisected it down and since it looks like an optimization to me I just
> reverted it - and voilá, the P4080 boots again.

It's not an optimization; it was required to get kdump working, at least
for certain choices of crash kernel location.  I just tried booting a 32-
bit kernel and did not see this problem -- but I don't have access to a
p4080ds anymore.  I tried with qemu e500mc, and also running a 32-bit
kernel on e6500 (needs a tiny change to get past SMP init, since 32-bit
isn't really supported on e6500, but you do get output even without that).

Do you have a JTAG that can be used to find out where it's hanging?  If
not, I can try to get early debug working (needs an early IOMMU mapping).

York, can you try booting the latest kernel on p4080ds?

-Scott

  reply	other threads:[~2018-09-21  0:31 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-20 22:48 [PATCH ppc-next] powerpc/fsl-booke: don't load early TLB at once David Lamparter
2018-09-21  0:31 ` Scott Wood [this message]
2018-09-21  1:00   ` David Lamparter
2018-09-22  5:45     ` Scott Wood
2018-10-01 14:26       ` David Lamparter
2018-09-21 17:40   ` York Sun
2018-09-21 17:47     ` Scott Wood
2018-09-21 18:07       ` York Sun
2018-10-01 13:51         ` David Lamparter
2018-09-24  5:15 ` Michael Ellerman

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=1537489893.7689.38.camel@redhat.com \
    --to=swood@redhat.com \
    --cc=equinox@diac24.net \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=oss@buserror.net \
    --cc=york.sun@nxp.com \
    /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).