linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Bjorn Helgaas <helgaas@kernel.org>
To: Huacai Chen <chenhuacai@gmail.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>,
	Huacai Chen <chenhuacai@loongson.cn>,
	Bjorn Helgaas <bhelgaas@google.com>,
	linux-pci <linux-pci@vger.kernel.org>,
	Jianmin Lv <lvjianmin@loongson.cn>,
	Rob Herring <robh+dt@kernel.org>
Subject: Re: [PATCH 4/5] PCI: Add quirk for multifunction devices of LS7A
Date: Tue, 18 May 2021 08:59:25 -0500	[thread overview]
Message-ID: <20210518135925.GA116106@bjorn-Precision-5520> (raw)
In-Reply-To: <CAAhV-H61Uc5D7+1pMR5xSJeBVXHwPttTtaPg6_gwJoYBywHjPA@mail.gmail.com>

[+cc Rob, beginning of thread
https://lore.kernel.org/r/20210514080025.1828197-5-chenhuacai@loongson.cn]

On Sat, May 15, 2021 at 11:52:53AM +0800, Huacai Chen wrote:
> On Fri, May 14, 2021 at 10:52 PM Jiaxun Yang <jiaxun.yang@flygoat.com> wrote:
> > 在 2021/5/14 16:00, Huacai Chen 写道:
> > > From: Jianmin Lv <lvjianmin@loongson.cn>
> > >
> > > In LS7A, multifunction device use same pci PIN and different
> > > irq for different function, so fix it for standard pci PIN
> > > usage.
> >
> > Hmm, I'm unsure about this change.
> > The PCIe port, or PCI-to-PCI bridge on LS7A only have a single
> > upstream interrupt specified in DeviceTree, how can this quirk
> > work?
>
> LS7A will be shared by MIPS-based Loongson and LoongArch-based
> Loongson, LoongArch use ACPI rather than FDT, so this quirk is needed.

Can you expand on this a little bit?

Which DT binding are you referring to?  Is it in the Linux source
tree?

I think Linux reads Interrupt Pin for both FDT and ACPI systems, and
apparently that register contains the same value for all functions of
this multi-function device.

The quirk will be applied for both FDT and ACPI systems, but it sounds
like you're saying this is needed *because* LoongArch uses ACPI.

Bjorn

  reply	other threads:[~2021-05-18 13:59 UTC|newest]

Thread overview: 39+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-14  8:00 [PATCH 0/5] PCI: Loongson-related pci quirks Huacai Chen
2021-05-14  8:00 ` [PATCH 1/5] PCI/portdrv: Don't disable pci device during shutdown Huacai Chen
2021-05-14 14:20   ` Krzysztof Wilczyński
2021-05-14 16:09   ` Bjorn Helgaas
2021-05-15  3:38     ` Huacai Chen
2021-05-14  8:00 ` [PATCH 2/5] PCI: Move loongson pci quirks to quirks.c Huacai Chen
2021-05-14  8:00 ` [PATCH 3/5] PCI: Improve the mrrs quirk for LS7A Huacai Chen
2021-05-14 14:03   ` Krzysztof Wilczyński
2021-05-14 15:39   ` Bjorn Helgaas
2021-05-15  3:49     ` Huacai Chen
2021-05-15  6:22       ` Jiaxun Yang
2021-05-14  8:00 ` [PATCH 4/5] PCI: Add quirk for multifunction devices of LS7A Huacai Chen
2021-05-14 13:22   ` Krzysztof Wilczyński
2021-05-14 14:52   ` Jiaxun Yang
2021-05-15  3:52     ` Huacai Chen
2021-05-18 13:59       ` Bjorn Helgaas [this message]
2021-05-19  2:26         ` Huacai Chen
2021-05-19  3:05           ` Jiaxun Yang
2021-05-14 15:51   ` Bjorn Helgaas
2021-05-15  3:56     ` Huacai Chen
2021-05-14  8:00 ` [PATCH 5/5] PCI: Support ASpeed VGA cards behind a misbehaving bridge Huacai Chen
2021-05-14 13:56   ` Krzysztof Wilczyński
2021-05-14 15:10   ` Bjorn Helgaas
2021-05-15  9:09     ` Huacai Chen
2021-05-17 12:53       ` Huacai Chen
2021-05-17 18:28         ` Bjorn Helgaas
2021-05-18  2:31           ` 隋景峰
2021-05-18  3:09             ` Bjorn Helgaas
2021-05-18  9:30               ` suijingfeng
2021-05-18 19:31                 ` Bjorn Helgaas
2021-05-18  7:13           ` Huacai Chen
2021-05-18 19:35             ` Bjorn Helgaas
2021-05-19  2:17               ` Huacai Chen
2021-05-19 19:33                 ` Bjorn Helgaas
2021-05-25 11:03                   ` Huacai Chen
2021-05-25 13:55                     ` Bjorn Helgaas
2021-05-26  2:33                       ` Huacai Chen
2021-05-26  3:00                         ` Dave Airlie
2021-05-26 18:29                           ` Bjorn Helgaas

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=20210518135925.GA116106@bjorn-Precision-5520 \
    --to=helgaas@kernel.org \
    --cc=bhelgaas@google.com \
    --cc=chenhuacai@gmail.com \
    --cc=chenhuacai@loongson.cn \
    --cc=jiaxun.yang@flygoat.com \
    --cc=linux-pci@vger.kernel.org \
    --cc=lvjianmin@loongson.cn \
    --cc=robh+dt@kernel.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).