All of lore.kernel.org
 help / color / mirror / Atom feed
From: Lukas Wunner <lukas@wunner.de>
To: liziyao@uniontech.com
Cc: Bjorn Helgaas <bhelgaas@google.com>,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
	loongarch@lists.linux.dev, niecheng1@uniontech.com,
	zhanjun@uniontech.com, guanwentao@uniontech.com,
	Kexy Biscuit <kexybiscuit@aosc.io>,
	Lain Fearyncess Yang <fsf@live.com>,
	Mingcong Bai <jeffbai@aosc.io>, Ayden Meng <aydenmeng@yeah.net>
Subject: Re: [PATCH RESEND] PCI: Override PCIe bridge supported speeds for older Loongson 3C6000 series steppings
Date: Sat, 23 Aug 2025 09:14:06 +0200	[thread overview]
Message-ID: <aKlqPoa6jeoNJEPc@wunner.de> (raw)
In-Reply-To: <20250822-loongson-pci1-v1-1-39aabbd11fbd@uniontech.com>

On Fri, Aug 22, 2025 at 05:15:58PM +0800, Ziyao via B4 Relay wrote:
> Older steppings of the Loongson 3C6000 series incorrectly report the
> supported link speeds on their PCIe bridges (device IDs 3c19, 3c29) as
> only 2.5 GT/s, despite the upstream bus supporting speeds from 2.5 GT/s
> up to 16 GT/s.

I assume these bridges (Root Ports?) are only found on LS3C6000 CPUs?

If so, please put the quirk in arch/loongarch/pci/pci.c or
drivers/pci/controller/pci-loongson.c alongside the existing fixups there.

drivers/pci/quirks.c is compiled on all arches and if these bridges
only exist on certain Loongson CPUs, the quirk isn't needed on other
arches and wastes memory.

Also, please consider adding entries for 3c19, 3c29 to the PCI IDs
database:

https://admin.pci-ids.ucw.cz/read/PC/0014

Thanks,

Lukas

      parent reply	other threads:[~2025-08-23  7:14 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-08-22  9:15 [PATCH RESEND] PCI: Override PCIe bridge supported speeds for older Loongson 3C6000 series steppings Ziyao
2025-08-22  9:15 ` Ziyao via B4 Relay
2025-08-22 20:26 ` kernel test robot
2025-08-23  7:14 ` Lukas Wunner [this message]

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=aKlqPoa6jeoNJEPc@wunner.de \
    --to=lukas@wunner.de \
    --cc=aydenmeng@yeah.net \
    --cc=bhelgaas@google.com \
    --cc=fsf@live.com \
    --cc=guanwentao@uniontech.com \
    --cc=jeffbai@aosc.io \
    --cc=kexybiscuit@aosc.io \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=liziyao@uniontech.com \
    --cc=loongarch@lists.linux.dev \
    --cc=niecheng1@uniontech.com \
    --cc=zhanjun@uniontech.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.