Re: [PATCH v6 0/3] Add new PCI_DEV_FLAGS_NO_RELAXED_ORDERING flag

[Ding Tianhong <dingtianhong@huawei.com>]

Hi Bjorn:

Could you please give some feedback about this patchset, it looks like no more comments for more than a week,
thanks. :)

Ding

On 2017/6/29 13:47, Ding Tianhong wrote:
> ping
> 
> On 2017/6/22 20:15, Ding Tianhong wrote:
>> Some devices have problems with Transaction Layer Packets with the Relaxed
>> Ordering Attribute set.  This patch set adds a new PCIe Device Flag,
>> PCI_DEV_FLAGS_NO_RELAXED_ORDERING, a set of PCI Quirks to catch some known
>> devices with Relaxed Ordering issues, and a use of this new flag by the
>> cxgb4 driver to avoid using Relaxed Ordering with problematic Root Complex
>> Ports.
>>
>> It's been years since I've submitted kernel.org patches, I appolgise for the
>> almost certain submission errors.
>>
>> v2: Alexander point out that the v1 was only a part of the whole solution,
>>     some platform which has some issues could use the new flag to indicate
>>     that it is not safe to enable relaxed ordering attribute, then we need
>>     to clear the relaxed ordering enable bits in the PCI configuration when
>>     initializing the device. So add a new second patch to modify the PCI
>>     initialization code to clear the relaxed ordering enable bit in the
>>     event that the root complex doesn't want relaxed ordering enabled.
>>
>>     The third patch was base on the v1's second patch and only be changed
>>     to query the relaxed ordering enable bit in the PCI configuration space
>>     to allow the Chelsio NIC to send TLPs with the relaxed ordering attributes
>>     set.
>>
>>     This version didn't plan to drop the defines for Intel Drivers to use the
>>     new checking way to enable relaxed ordering because it is not the hardest
>>     part of the moment, we could fix it in next patchset when this patches
>>     reach the goal.  
>>
>> v3: Redesigned the logic for pci_configure_relaxed_ordering when configuration,
>>     If a PCIe device didn't enable the relaxed ordering attribute default,
>>     we should not do anything in the PCIe configuration, otherwise we
>>     should check if any of the devices above us do not support relaxed
>>     ordering by the PCI_DEV_FLAGS_NO_RELAXED_ORDERING flag, then base on
>>     the result if we get a return that indicate that the relaxed ordering
>>     is not supported we should update our device to disable relaxed ordering
>>     in configuration space. If the device above us doesn't exist or isn't
>>     the PCIe device, we shouldn't do anything and skip updating relaxed ordering
>>     because we are probably running in a guest.
>>
>> v4: Rename the functions pcie_get_relaxed_ordering and pcie_disable_relaxed_ordering
>>     according John's suggestion, and modify the description, use the true/false
>>     as the return value.
>>
>>     We shouldn't enable relaxed ordering attribute by the setting in the root
>>     complex configuration space for PCIe device, so fix it for cxgb4.
>>
>>     Fix some format issues.
>>
>> v5: Removed the unnecessary code for some function which only return the bool
>>     value, and add the check for VF device.
>>
>>     Make this patch set base on 4.12-rc5.
>>
>> v6: Fix the logic error in the need to enable the relaxed ordering attribute for cxgb4.
>>  
>> Casey Leedom (2):
>>   PCI: Add new PCIe Fabric End Node flag,
>>     PCI_DEV_FLAGS_NO_RELAXED_ORDERING
>>   net/cxgb4: Use new PCI_DEV_FLAGS_NO_RELAXED_ORDERING flag
>>
>> Ding Tianhong (1):
>>   PCI: Enable PCIe Relaxed Ordering if supported
>>
>>  drivers/net/ethernet/chelsio/cxgb4/cxgb4.h      |  1 +
>>  drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c | 17 ++++++++++
>>  drivers/net/ethernet/chelsio/cxgb4/sge.c        |  5 +--
>>  drivers/pci/pci.c                               | 32 +++++++++++++++++++
>>  drivers/pci/probe.c                             | 41 +++++++++++++++++++++++++
>>  drivers/pci/quirks.c                            | 38 +++++++++++++++++++++++
>>  include/linux/pci.h                             |  4 +++
>>  7 files changed, 136 insertions(+), 2 deletions(-)
>>