All of lore.kernel.org
 help / color / mirror / Atom feed
From: Rob Herring <robh@kernel.org>
To: "Pali Rohár" <pali@kernel.org>
Cc: "Jason Cooper" <jason@lakedaemon.net>,
	"Andrew Lunn" <andrew@lunn.ch>,
	"Gregory Clement" <gregory.clement@bootlin.com>,
	"Sebastian Hesselbarth" <sebastian.hesselbarth@gmail.com>,
	"Thomas Petazzoni" <thomas.petazzoni@bootlin.com>,
	"Lorenzo Pieralisi" <lorenzo.pieralisi@arm.com>,
	"Andrew Murray" <amurray@thegoodpenguin.co.uk>,
	"Bjorn Helgaas" <bhelgaas@google.com>,
	"Remi Pommarel" <repk@triplefau.lt>,
	"Marek Behún" <marek.behun@nic.cz>,
	"Tomasz Maciej Nowak" <tmn505@gmail.com>,
	Xogium <contact@xogium.me>,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-pci@vger.kernel.org
Subject: Re: [PATCH v4 02/12] PCI: aardvark: Don't blindly enable ASPM L0s and don't write to read-only register
Date: Thu, 7 May 2020 16:07:13 -0500	[thread overview]
Message-ID: <20200507210713.GA26756@bogus> (raw)
In-Reply-To: <20200430080625.26070-3-pali@kernel.org>

On Thu, 30 Apr 2020 10:06:15 +0200, =?UTF-8?q?Pali=20Roh=C3=A1r?= wrote:
> Trying to change Link Status register does not have any effect as this
> is a read-only register. Trying to overwrite bits for Negotiated Link
> Width does not make sense.
> 
> In future proper change of link width can be done via Lane Count Select
> bits in PCIe Control 0 register.
> 
> Trying to unconditionally enable ASPM L0s via ASPM Control bits in Link
> Control register is wrong. There should be at least some detection if
> endpoint supports L0s as isn't mandatory.
> 
> Moreover ASPM Control bits in Link Control register are controlled by
> pcie/aspm.c code which sets it according to system ASPM settings,
> immediately after aardvark driver probes. So setting these bits by
> aardvark driver has no long running effect.
> 
> Remove code which touches ASPM L0s bits from this driver and let
> kernel's ASPM implementation to set ASPM state properly.
> 
> Some users are reporting issues that this code is problematic for some
> Intel wifi cards and removing it fixes them, see e.g.:
> https://bugzilla.kernel.org/show_bug.cgi?id=196339
> 
> If problems with Intel wifi cards occur even after this commit, then
> pcie/aspm.c code could be modified / hooked to not enable ASPM L0s state
> for affected problematic cards.
> 
> Signed-off-by: Pali Rohár <pali@kernel.org>
> ---
>  drivers/pci/controller/pci-aardvark.c | 4 ----
>  1 file changed, 4 deletions(-)
> 

Acked-by: Rob Herring <robh@kernel.org>

  reply	other threads:[~2020-05-07 21:07 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-30  8:06 [PATCH v4 00/12] PCI: aardvark: Fix support for Turris MOX and Compex wifi cards Pali Rohár
2020-04-30  8:06 ` [PATCH v4 01/12] PCI: aardvark: Train link immediately after enabling training Pali Rohár
2020-05-04 15:50   ` Bjorn Helgaas
2020-05-07 21:05   ` Rob Herring
2020-04-30  8:06 ` [PATCH v4 02/12] PCI: aardvark: Don't blindly enable ASPM L0s and don't write to read-only register Pali Rohár
2020-05-07 21:07   ` Rob Herring [this message]
2020-04-30  8:06 ` [PATCH v4 03/12] PCI: of: Zero max-link-speed value is invalid Pali Rohár
2020-05-07 21:07   ` Rob Herring
2020-04-30  8:06 ` [PATCH v4 04/12] PCI: aardvark: Improve link training Pali Rohár
2020-05-07 21:10   ` Rob Herring
2020-04-30  8:06 ` [PATCH v4 05/12] PCI: aardvark: Issue PERST via GPIO Pali Rohár
2020-04-30  8:22   ` Pali Rohár
2020-05-07 21:20     ` Rob Herring
2020-04-30  8:06 ` [PATCH v4 06/12] PCI: aardvark: Add FIXME comment for PCIE_CORE_CMD_STATUS_REG access Pali Rohár
2020-05-07 21:20   ` Rob Herring
2020-04-30  8:06 ` [PATCH v4 07/12] PCI: aardvark: Add PHY support Pali Rohár
2020-05-07 21:23   ` Rob Herring
2020-04-30  8:06 ` [PATCH v4 08/12] PCI: aardvark: Replace custom macros by standard linux/pci_regs.h macros Pali Rohár
2020-05-04 15:52   ` Bjorn Helgaas
2020-05-07 21:24   ` Rob Herring
2020-04-30  8:06 ` [PATCH v4 09/12] dt-bindings: PCI: aardvark: Describe new properties Pali Rohár
2020-05-07 21:25   ` Rob Herring
2020-04-30  8:06 ` [PATCH v4 10/12] arm64: dts: marvell: armada-37xx: Set pcie_reset_pin to gpio function Pali Rohár
2020-04-30  8:06 ` [PATCH v4 11/12] arm64: dts: marvell: armada-37xx: Move PCIe comphy handle property Pali Rohár
2020-04-30  8:06 ` [PATCH v4 12/12] arm64: dts: marvell: armada-37xx: Move PCIe max-link-speed property Pali Rohár
2020-05-04 15:50   ` Bjorn Helgaas
2020-05-08 13:11 ` [PATCH v4 00/12] PCI: aardvark: Fix support for Turris MOX and Compex wifi cards Tomasz Maciej Nowak
2020-05-13 11:16 ` Pali Rohár
2020-05-13 11:33   ` Lorenzo Pieralisi
2020-05-13 11:59     ` Pali Rohár
2020-05-13 11:56 ` Thomas Petazzoni
2020-05-17 15:57   ` Gregory CLEMENT
2020-05-18 10:30     ` Pali Rohár
2020-05-18 13:46       ` Lorenzo Pieralisi
2020-05-18 13:50         ` Marek Behun

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=20200507210713.GA26756@bogus \
    --to=robh@kernel.org \
    --cc=amurray@thegoodpenguin.co.uk \
    --cc=andrew@lunn.ch \
    --cc=bhelgaas@google.com \
    --cc=contact@xogium.me \
    --cc=devicetree@vger.kernel.org \
    --cc=gregory.clement@bootlin.com \
    --cc=jason@lakedaemon.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=marek.behun@nic.cz \
    --cc=pali@kernel.org \
    --cc=repk@triplefau.lt \
    --cc=sebastian.hesselbarth@gmail.com \
    --cc=thomas.petazzoni@bootlin.com \
    --cc=tmn505@gmail.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.