Visible to Intel only — GUID: nik1410905541503
Ixiasoft
Visible to Intel only — GUID: nik1410905541503
Ixiasoft
4.11. Local Management Interface (LMI) Signals
The LMI interface is synchronous to pld_clk and runs at frequencies up to 250 MHz. The LMI address is the same as the Configuration Space address. The read and write data are always 32 bits. The LMI interface provides the same access to Configuration Space registers as Configuration TLP requests. Register bits have the same attributes, (read only, read/write, and so on) for accesses from the LMI interface and from Configuration TLP requests.
LMI writes may conflict with Host writes to the Configuration Space. When such a conflict occurs one of the accesses is successful and the other is dropped. The successful access cannot be determined a priori and no notification of success or failure is given to either the Application Layer or the Host.
All LMI reads are also held and executed when no configuration TLP requests are pending. The LMI interface supports two operations: local read and local write. The timing for these operations complies with the Avalon-MM protocol described in the Avalon Interface Specifications. LMI reads can be issued at any time to obtain the contents of any Configuration Space register. LMI write operations are not recommended for use during normal operation. The Configuration Space registers are written by requests received from the PCI Express link and there may be unintended consequences of conflicting updates from the link and the LMI interface. LMI Write operations are provided for AER header logging, and debugging purposes only.
Signal |
Direction |
Description |
---|---|---|
lmi_dout[31:0] | Output |
Data outputs. Valid when lmi_ack_apphas been asserted. |
lmi_rden | Input |
Read enable input. |
lmi_wren | Input |
Write enable input. |
lmi_ack | Output |
Acknowledgment for a read or write operation. The SR-IOV Bridge asserts this output for one cycle after it has completed the read or write operation. For read operations, the assertion of lmi_ack also indicates the presence of valid data on lmi_dout. |
lmi_addr[11:0] | Input |
Byte address of 32-bit configuration register. Bits [1:0] are not used. |
lmi_func[8:0] | Input | Bit [8] directs the LMI read or write operation to either the Hard IP or the Function configuration spaces implemented in the SR-IOV Bridge. The following encodings are defined:
Bits [7:0] specify the function number corresponding to the LMI access. Used only when the LMI access is to a configuration register in the SR-IOV Bridge. |
lmi_din[31:0] | Input |
Data inputs. |