From mboxrd@z Thu Jan 1 00:00:00 1970 From: okaya@codeaurora.org (Sinan Kaya) Date: Tue, 10 Apr 2018 16:18:01 -0400 Subject: [PATCH] PCI: quirk HT1100 & HT2000 and one HT2100 Root Ports for Extended Tags In-Reply-To: <20180410195008.GE54986@bhelgaas-glaptop.roam.corp.google.com> References: <1522882209-9743-1-git-send-email-okaya@codeaurora.org> <20180410194144.GD54986@bhelgaas-glaptop.roam.corp.google.com> <20180410195008.GE54986@bhelgaas-glaptop.roam.corp.google.com> Message-ID: <1c94361d-7a8d-ad18-12e5-1612326a54db@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 4/10/2018 3:50 PM, Bjorn Helgaas wrote: > On Tue, Apr 10, 2018 at 02:41:44PM -0500, Bjorn Helgaas wrote: >> On Wed, Apr 04, 2018 at 06:50:09PM -0400, Sinan Kaya wrote: >>> Per PCIe r3.1, sec 2.2.6.2 and 7.8.4, a Requester may not use 8-bit Tags >>> unless its Extended Tag Field Enable is set, but all Receivers/Completers >>> must handle 8-bit Tags correctly regardless of their Extended Tag Field >>> Enable. >>> >>> Some devices do not handle 8-bit Tags as Completers, so add a quirk for >>> them. If we find such a device, we disable Extended Tags for the entire >>> hierarchy to make peer-to-peer DMA possible. >>> >>> The Broadcom HT1100/HT2000/HT2100 seems to have issues with handling 8-bit >>> tags. Mark it as broken. >>> >>> Fixes: 60db3a4d8cc9 ("PCI: Enable PCIe Extended Tags if supported") >>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=196197 >>> Signed-off-by: Sinan Kaya >> Applied to pci/enumeration for v4.18, thanks! > Actually, this is a really annoying issue and I think the fix is > appropriate for v4.17, so I moved it to my for-linus branch. > I agree. It causes boot issues on some AMD Opteron machines. It should probably be back-ported too. -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.