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MSI with avalonMM-DMA ip

OlegT
New Contributor I
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Hello.
I use pcie HIP with avalon-mm-dma interface, as an endpoint. Cyclone10GX evaluation kit.
I need to send custom MSI to root complex (ubuntu PC).
rxm_irq signals are not available due to mm-dma interface.
1. As I understand, I have to collect data from MSIIntfc_o[81:0] and send TLP via TXS port.
Am I right?

2. MSIIntfc_o contains an information about only one MSI vector.If I want to use more vectors, how can I get address and data to generate TLPs for other vectors?

Thank you.

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KhaiChein_Y_Intel
1,031 Views

Hi,


I could not find the part that you have mentioned in the document. May I know which document you are referring to?


According to the PCI Local Bus Specification 2.3,

"If the Multiple Message Enable field (bits 6-4 of the Message Control register) is non-zero, the device is permitted to modify the low order bits of the message data to generate multiple messages."


Thanks

Best regards,

KhaiY




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KhaiChein_Y_Intel
1,100 Views

Hi,

 

1. Yes. You have to use this interface to receive information required to generate MSI interrupts to the Root Port via the TX Slave interface.

2. You have to design a Custom Interrupt Handler. You may refer to Figure 51 for an overview of the logic for the Custom Interrupt Handler. The Custom Interrupt Handler should include hardware to perform the following tasks:

  • An MSI/MSI-X IRQ Avalon-MM Master port to drive MSI or MSI-X interrupts as
    memory writes to the PCIe Avalon-MM bridge.
  • A legacy interrupt signal, IntxReq_i, to drive legacy interrupts from the MSI/
    MSI-X IRQ module to the Hard IP for PCI Express.
  • An MSI/MSI-X Avalon-MM Slave port to receive interrupt control and status from
    the PCIe Root Port.
  • An MSI-X table to store the MSI-X table entries. The PCIe Root Port sets up this
    table.

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/ug/ug_a10_pcie_avmm.pdf

Thanks

Best regards,

KhaiY

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OlegT
New Contributor I
1,053 Views

As I've found in docs, the MSI vectors differ only in LSBits of data field. All of them use the same address. 

Data field should be masked accordingly to count of vectors (2 - 0xFE, 4 - 0xFC, 8 - 0xF8 and so on) and then OR-ed with vector number.

Is it true?

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KhaiChein_Y_Intel
1,032 Views

Hi,


I could not find the part that you have mentioned in the document. May I know which document you are referring to?


According to the PCI Local Bus Specification 2.3,

"If the Multiple Message Enable field (bits 6-4 of the Message Control register) is non-zero, the device is permitted to modify the low order bits of the message data to generate multiple messages."


Thanks

Best regards,

KhaiY




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OlegT
New Contributor I
1,027 Views

Thank you, 

We are talking about same things.

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KhaiChein_Y_Intel
999 Views

Hi,


I’m glad that your question has been addressed, I now transition this thread to community support. If you have a new question, feel free to open a new thread to get the support from Intel experts. Otherwise, the community users will continue to help you on this thread. Thank you.


Best regards,

KhaiY


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