Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1440443

Re: PCIe MSI address is not written at pci_enable_msi_range call

From Marc Zyngier <marc.zyngier@arm.com>
Newsgroups linux.kernel
Subject Re: PCIe MSI address is not written at pci_enable_msi_range call
Date 2016-07-11 12:30 +0200
Message-ID <rTGDo-5Kn-19@gated-at.bofh.it> (permalink)
References <rTzsd-110-5@gated-at.bofh.it> <rTF4B-4Da-9@gated-at.bofh.it> <rTFR0-59c-15@gated-at.bofh.it>
Organization ARM Ltd

Show all headers | View raw


[Please don't top-post]

On 11/07/16 10:33, Bharat Kumar Gogada wrote:
> Hi Marc,
> 
> Thanks for the reply.
> 
> From PCIe Spec:
> MSI Enable Bit:
> If 1 and the MSI-X Enable bit in the MSI-X Message
> Control register (see Section 6.8.2.3) is 0, the
> function is permitted to use MSI to request service
> and is prohibited from using its INTx# pin.
> 
> From Endpoint perspective, MSI Enable = 1 indicates MSI can be used which means MSI address and data fields are available/programmed.
> 
> In our SoC whenever MSI Enable goes from 0 --> 1 the hardware latches onto MSI address and MSI data values.
> 
> With current MSI implementation in kernel, our SoC is latching on to incorrect address and data values, as address/data
> are updated much later than MSI Enable bit.

Interesting. It looks like we're doing something wrong in the MSI flow.
Can you confirm that this is limited to MSI and doesn't affect MSI-X?

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-11 04:50 +0200
  Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-11 10:50 +0200
    RE: PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-11 11:40 +0200
      Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-11 12:30 +0200
        RE: PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-11 13:00 +0200
          Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-11 18:00 +0200
            RE: PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-12 11:20 +0200
              Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-12 16:30 +0200
      Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-12 18:00 +0200
        RE: PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-13 08:30 +0200
          Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-13 10:20 +0200
            Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-13 10:40 +0200
              RE: PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-13 11:20 +0200
                Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-13 11:20 +0200
                RE: PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-13 11:40 +0200
                Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-13 11:50 +0200
                RE: PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-13 17:40 +0200
                Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-13 17:50 +0200
            RE: PCIe MSI address is not written at pci_enable_msi_range call Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com> - 2016-07-13 10:40 +0200
              Re: PCIe MSI address is not written at pci_enable_msi_range call Marc Zyngier <marc.zyngier@arm.com> - 2016-07-20 14:20 +0200

csiph-web