From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Raj, Ashok" <ashok.raj@intel.com>
Subject: Re: [PATCH 1/2] PCI: Add new PCIe Fabric End Node flag,
 PCI_DEV_FLAGS_NO_RELAXED_ORDERING
Date: Tue, 2 May 2017 09:44:01 -0700
Message-ID: <20170502164400.GA26406@linux.intel.com>
References: <cover.1493678834.git.leedom@chelsio.com>
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Cc: Bjorn Helgaas <helgaas@kernel.org>, leedom@gmail.com,
        Michael Werner <werner@chelsio.com>,
        Ganesh Goudar <ganeshgr@chelsio.com>,
        Arjun V <arjun@chelsio.com>,
        David Miller <davem@davemloft.com>,
        Asit K Mallick <asit.k.mallick@intel.com>,
        Patrick J Cramer <patrick.j.cramer@intel.com>,
        Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>,
        Bob Shaw <Bob.Shaw@amd.com>, h <l.stach@pengutronix.de>,
        Alexander Duyck <alexander.duyck@gmail.com>,
        Ding Tianhong <dingtianhong@huawei.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Amir Ancel <amira@mellanox.com>,
        Gabriele Paoloni <gabriele.paoloni@huawei.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        LinuxArm <linuxarm@huawei.com>,
        David Laight <David.Laight@aculab.com>,
        je
To: Casey Leedom <leedom@chelsio.com>
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Hi Casey


On Mon, May 01, 2017 at 04:13:50PM -0700, Casey Leedom wrote:
> The new flag PCI_DEV_FLAGS_NO_RELAXED_ORDERING indicates that the Relaxed
> Ordering Attribute should not be used on Transaction Layer Packets destined
> for the PCIe End Node so flagged.  Initially flagged this way are Intel
> E5-26xx Root Complex Ports which suffer from a Flow Control Credit
> Performance Problem and AMD A1100 ARM ("SEATTLE") Root Complex Ports which
> don't obey PCIe 3.0 ordering rules which can lead to Data Corruption.
> ---
>  drivers/pci/quirks.c | 38 ++++++++++++++++++++++++++++++++++++++
>  include/linux/pci.h  |  2 ++
>  2 files changed, 40 insertions(+)
> 
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index f754453..4ae78b3 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -3979,6 +3979,44 @@ static void quirk_tw686x_class(struct pci_dev *pdev)
>  			      quirk_tw686x_class);
>  
>  /*
> + * Some devices have problems with Transaction Layer Packets with the Relaxed
> + * Ordering Attribute set.  Such devices should mark themselves and other
> + * Device Drivers should check before sending TLPs with RO set.
> + */
> +static void quirk_relaxedordering_disable(struct pci_dev *dev)
> +{
> +	dev->dev_flags |= PCI_DEV_FLAGS_NO_RELAXED_ORDERING;
> +}
> +
> +/*
> + * Intel E5-26xx Root Complex has a Flow Control Credit issue which can
> + * cause performance problems with Upstream Transaction Layer Packets with
> + * Relaxed Ordering set.
> + */
> +DECLARE_PCI_FIXUP_CLASS_EARLY(0x8086, 0x6f02, PCI_CLASS_NOT_DEFINED, 8,
> +			      quirk_relaxedordering_disable);
> +DECLARE_PCI_FIXUP_CLASS_EARLY(0x8086, 0x6f04, PCI_CLASS_NOT_DEFINED, 8,
> +			      quirk_relaxedordering_disable);
> +DECLARE_PCI_FIXUP_CLASS_EARLY(0x8086, 0x6f08, PCI_CLASS_NOT_DEFINED, 8,
> +			      quirk_relaxedordering_disable);
> +

You might want to add the RP ID's for both HSX/BDX. Tne entire range 
is 2F01H-2F0EH & 6F01H-6F0EH.

Cheers,
Ashok