All of lore.kernel.org
 help / color / mirror / Atom feed
From: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: "Luís Mendes" <luis.p.mendes@gmail.com>,
	"Linux PCI" <linux-pci@vger.kernel.org>,
	"Thomas Petazzoni" <thomas.petazzoni@bootlin.com>,
	"Jason Cooper" <jason@lakedaemon.net>,
	"Benjamin Herrenschmidt" <benh@kernel.crashing.org>
Subject: Re: Problem with PCIe enumeration of Google/Coral TPU Edge module on Linux
Date: Sun, 8 Mar 2020 05:51:15 +0000	[thread overview]
Message-ID: <PSXP216MB04382D268822AD1C3D9A57C780E10@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM> (raw)
In-Reply-To: <20200307213853.GA208095@google.com>

Hi,
> > On Sat, Mar 7, 2020 at 12:11 PM Luís Mendes <luis.p.mendes@gmail.com> wrote:
> > > This issue seems to happen only with the Coral Edge TPU device, but it
> > > happens independently of whether the gasket/apex driver module is
> > > loaded or not. The BAR 0 of the Coral device is not assigned either
> > > way.
> > >
> > > Luís

So the problem only occurs with the Coral Edge TPU device, so there is a 
possibility that it is not a problem with the platform, or something 
caused by the combination of the TPU and platform. Is it possible to put 
the TPU into an X86 system with the same kernel version(s) to add more 
evidence to this theory? If it works on X86 then we can focus on the 
differences between X86 and ARM.

Also, please revert c13704f5685d "PCI: Avoid double hpmemsize MMIO 
window assignment" or try with Linux v5.4 which does not have this 
commit, just to rule out the possibility of it causing issues. This 
patch helps me and also solved the problem of one other person using an 
ARM computer who came to us regarding a problem. However, it could also 
adversely affect unknown use cases - it is impossible to completely rule 
out, due to the nature of how drivers/pci/setup-bus.c is written.

Kind regards,
Nicholas

  reply	other threads:[~2020-03-08  5:51 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-06 14:32 Problem with PCIe enumeration of Google/Coral TPU Edge module on Linux Luís Mendes
2020-03-06 21:47 ` Bjorn Helgaas
2020-03-07 12:11   ` Luís Mendes
2020-03-07 15:26     ` Luís Mendes
2020-03-07 21:38       ` Bjorn Helgaas
2020-03-08  5:51         ` Nicholas Johnson [this message]
2020-03-09 11:21           ` Luís Mendes
2020-03-11 14:20             ` Luís Mendes
2020-03-29 22:11               ` Luís Mendes
2020-03-30 19:49                 ` Bjorn Helgaas
2020-03-31 21:28                   ` Luís Mendes
2020-04-01 18:16                     ` Bjorn Helgaas
2020-04-01 21:20                       ` Luís Mendes
2020-04-01 21:55                         ` Luís Mendes
2020-04-01 23:31                         ` Bjorn Helgaas
2020-04-02 14:13                           ` Luís Mendes
2020-04-04  1:32                             ` Bjorn Helgaas
2020-04-04 21:39                               ` Luís Mendes
2020-04-08 23:05                                 ` Luís Mendes
2020-04-09 15:25                                   ` Luís Mendes
2020-04-09 15:29                                     ` Luís Mendes
2020-04-09 16:30                                     ` Bjorn Helgaas
2020-04-09 17:32                                       ` Luís Mendes
2020-04-09 18:08                                       ` Bjorn Helgaas
2020-04-09 20:07                                         ` Luís Mendes

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=PSXP216MB04382D268822AD1C3D9A57C780E10@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM \
    --to=nicholas.johnson-opensource@outlook.com.au \
    --cc=benh@kernel.crashing.org \
    --cc=helgaas@kernel.org \
    --cc=jason@lakedaemon.net \
    --cc=linux-pci@vger.kernel.org \
    --cc=luis.p.mendes@gmail.com \
    --cc=thomas.petazzoni@bootlin.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.