Configuration Transmit Message Interface - 1.3 English

This signal is asserted together with cfg_msg_transmit_type, which supplies the encoded message type and cfg_msg_transmit_data, which supplies optional data associated with the message, until cfg_msg_transmit_done is asserted in response.

Indicates the type of PCI Express message to be transmitted. Encodings supported are:

• 000b: Latency Tolerance Reporting (LTR)
• 001b: Optimized Buffer Flush/Fill (OBFF)
• 010b: Set Slot Power Limit (SSPL)
• 011b: Power Management (PM PME)
• 100b -111b: Reserved

Indicates message data associated with particular message type.

000b: LTR -

• cfg_msg_transmit_data[31] < Snoop Latency Req
• cfg_msg_transmit_data[28:26] < Snoop Latency Scale
• cfg_msg_transmit_data[25:16] < Snoop Latency Value
• cfg_msg_transmit_data[15] < No-Snoop Latency Requirement
• cfg_msg_transmit_data[12:10] < No-Snoop Latency Scale
• cfg_msg_transmit_data[9:0] < No-Snoop Latency Value

001b: OBFF -

• cfg_msg_transmit_data[3:0] < OBFF Code

010b: SSPL -

• cfg_msg_transmit_data[9:0] < {Slot Power Limit Scale, Slot Power Limit Value}

011b: PM_PME -

• cfg_msg_transmit_data[1:0] < PF1, PF0
• cfg_msg_transmit_data[9:4] < VF5, VF4, VF3, VF2, VF1, VF0, where one or more PFs or VFs can signal PM_PME simultaneously.

100b - 111b: Reserved

Asserted in response to cfg_mg_transmit assertion, for 1 cycle after the request is complete.