MSI Interrupt Interface - 3.4 English

Versal Adaptive SoC CPM Mode for PCI Express Product Guide (PG346)
Document ID
PG346
Release Date
2024-11-22
Version
3.4 English
Table 1. MSI Interrupt Interface Port Descriptions
Name I/O Width Description

pcie0_cfg_msi_enable

pcie1_cfg_msi_enable

 O

4 in CPM4

1 in CPM5

 Configuration Interrupt MSI Function Enabled
Indicates that the Message Signaling Interrupt (MSI) messaging is enabled, per Function. These outputs reflect the setting of the MSI Enable bits in the MSI Control Register of Physical Functions 0 – 3.
Note: In CPM5, only the Function 0 setting is indicated. For subsequent functions, the wrreq interface is used.
pcie0_cfg_msi_int_vector pcie1_cfg_msi_int_vector I 32 Configuration Interrupt MSI Vector

When configured in the Endpoint mode to support MSI interrupts, these inputs are used to signal the 32 distinct interrupt conditions associated with a PCI Function (Physical or Virtual) from the user logic to the core. The Function number must be specified on the input pcie(n)_cfg_msi_function_number. After placing the Function number on the input pcie(n)_cfg_msi_function_number, the user logic must activateone of these signals for one cycle to transmit an interrupt.The user logic must not activate more than one of the 32 interrupt inputs in the same cycle. The core internally registers the interrupt condition on the 0-to-1 transition of any bit in pcie(n)_cfg_msi_mint_vector. After asserting an interrupt, the user logic must wait for the pcie0_cfg_msi_sent or pcie0_cfg_msi_fail indication from the core before asserting a new interrupt.
pcie0_cfg_msi_function_number

pcie1_cfg_msi_function_number

 I

8 in CPM4

16 in CPM5

 Configuration MSI Initiating Function in CPM4.

Indicates the Endpoint Function # initiating the MSI interrupt.

  • 8'h00 – 8'h03: PF 0 – PF 3
  • 8’h04 – 8’hFF: VF 0 – VF 252
  • Other encodings are reserved.

Configuration MSI Initiating Function in CPM5

Indicates the Endpoint function # initiating the MSI transaction.

  • 16'h0000-16'h100F is the supported range.
  • Other encodings are reserved.
pcie0_cfg_msi_sent O 1 Configuration Interrupt MSI Interrupt Sent

The core generates a one-cycle pulse on this output to signal that an MSI interrupt message has been transmitted on the link. The user logic must wait for this pulse before signaling another interrupt condition to the core.
pcie0_cfg_msi_fail O 1 Configuration Interrupt MSI Interrupt Operation Failed

A one-cycle pulse on this output indicates that an MSI interrupt message was aborted before transmission on the link. The user logic must retransmit the MSI or MSI-X interrupt in this case.
pcie0_cfg_msi_mmenable

pcie1_cfg_msi_mmenable

 O

12 in CPM4

3 in CPM5

 Configuration Interrupt MSI Function Multiple Message Enable

When the core is configured in the Endpoint mode to support MSI interrupts, these outputs are driven by the 'Multiple Message Enable' bits of the MSI Control Register associated with Physical Functions. These bits encode the number of allocated MSI interrupt vectors for the corresponding Function. Bits [2:0] correspond to Physical Function 0, bits [5:3] correspond to PF 1, and so on. The valid encodings of the 3 bits are:

  • 000b: 1 vector
  • 001b: 2 vectors
  • 010b: 4 vectors
  • 011b: 8 vectors
  • 100b: 16 vectors
  • 101b: 32 vectors
Note: In CPM5, only the Function 0 setting is indicated. For subsequent functions, the wrreq interface is used.
pcie0_cfg_msi_pending_status pcie1_cfg_msi_pending_status I 32 Configuration MSI Interrupt Pending Status

These inputs are provided for the user to indicate the interrupt pending status of the MSI interrupts associated with the Physical Functions. When the status of a MSI interrupt associated with a PF changes, the user must place the new interrupt status on these inputs, along with the corresponding Function number on the pcie(n)_cfg_msi_pending_status_function_num input, and activate the pcie(n)_cfg_msi_pending_status_data_enable input for one cycle. The core then latches the new status in its MSI Pending Bits Register of the corresponding Physical Function.

pcie0_cfg_msi_pending_status_function_num

pcie1_cfg_msi_pending_status_function_num		 I

2 in CPM4

4 in CPM5

 Configuration Interrupt MSI Pending Target Function Number
  • 00 = PF 0
  • 01 = PF 1
  • 10 = PF 2
  • 11 = PF 3
  • 100 = PF 4
  • 101 = PF 5
  • 110 = PF 6
  • 111 = PF 7
  • 1000 = PF 8
  • 1001 = PF 9
  • 1010 = PF 10
  • 1011 = PF 11
  • 1100 = PF 12
  • 1101 = PF 13
  • 1110 = PF 14
  • 1111 = PF 15

This input is used to identify the Function number when the user places interrupt status on the pcie(n)_cfg_msi_pending_status inputs.
pcie0_cfg_msi_pending_status_data_enable pcie1_cfg_msi_pending_status_data_enable I 1 Configuration Interrupt MSI Pending Data Valid

The user application asserts this signal together with pcie(n)_cfg_msi_pending_status and pcie(n)_cfg_msi_pending_status_function_num values to update the MSI Pending Bits in the corresponding function.
pcie0_cfg_msi_mask_update O 1 Configuration Interrupt MSI Function Mask Updated

The SR-IOV core asserts this for 1 cycle when the MSI Mask Register of any enabled PFs has changed its value. The user can then read the new mask settings from the pcie(n)_cfg_msi_data outputs.

pcie0_cfg_msi_select
pcie1_cfg_msi_select

 I

2 in CPM4

4 in CPM5

 Configuration Interrupt MSI Select

These inputs are used to select the Function number for reading the MSI Mask Register setting from the core. Values 0 – 15 correspond to Physical Functions 0 – 15, respectively. The mask MSI Mask Register contents of the selected PF appear on the output pcie(n)_cfg_msi_data after one cycle.

pcie1_cfg_msi_data
pcie1_cfg_msi_data

O 32 Configuration Interrupt MSI Data

These output reflect the MSI Mask Register setting of the Physical Function selected by the pcie(n)_cfg_msi_select input.

pcie0_cfg_msi_attr
pcie1_cfg_msi_attr

 I 3 Configuration Interrupt MSI/MSI-X TLP Attribute

These bits enable you to set the Attribute bits that are used for both MSI and MSI-X interrupt requests.

  • Bit 0 is the No Snoop bit.
  • Bit 1 is the Relaxed Ordering bit.
  • Bit 2 is the ID-Based Ordering bit.

The core samples these bits on a 0-to-1 transition on pcie(n)_cfg_msi_mint_vector bits (when using MSI) or pcie(n)_cfg_msix_int (when using MSI-X).

pcie0_cfg_msi_tph_present

pcie1_cfg_msi_tph_present

   1 Configuration Interrupt MSI/MSI-X TPH Present. Indicates the presence of an optional Transaction Processing Hint (TPH) in the MSI/MSI-X interrupt request. The user application must set this bit while asserting pcie(n)_cfg_msi_mint_vector bits (when using MSI), or pcie(n)_cfg_msix_int_vector (when using MSI-X), if it is including a TPH in the MSI or MSI-X transaction.
Note: These bits are reserved.

pcie0_cfg_msi_tph_type

pcie1_cfg_msi_tph_type

   2 Configuration Interrupt MSI/MSI-X TPH Type. When pcie(n)_cfg_msi_tph_present is 1'b1, these two bits are used to supply the 2-bit type associated with the Hint. The core samples these bits on 0-to-1 transition on any bit of pcie(n)_cfg_msi_mint_vector or pcie(n)_cfg_msix_int_vector, depending on whether MSI or MSI-X interrupts are used.
Note: These bits are reserved.

pcie0_cfg_msi_tph_st_tag

pcie1_cfg_msi_tph_st_tag

   8 Configuration Interrupt MSI/MSI-X TPH Steering Tag When pcie(n)_cfg_msi_tph_present is asserted, the SteeringTag associated with the Hint must be placed on pcie(n)_cfg_msi_tph_st_tag[7:0]. The core samples these bits on 0-to-1 transition on any bit of pcie(n)_cfg_msi_mint_vector or pcie(n)_cfg_msix_int_vector, depending on whether MSI or MSI-X interrupts are used.
Note: These bits are reserved.