Programming model for avalon‑mm root port – Altera Arria V Avalon-MM User Manual

Page 88

Advertising
background image

Byte Offset

Register

Dir

Description

• 10011: Loopback.Exit

• 10100: Hot.Reset

• 10101: LOs

• 11001: L2.transmit.Wake

• 11010: Speed.Recovery

• 11011: Recovery.Equalization, Phase 0

• 11100: Recovery.Equalization, Phase 1

• 11101: Recovery.Equalization, Phase 2

• 11110: recovery.Equalization, Phase 3

14'h3C68

current_speed_reg[1:0]

O

Indicates the current speed of the PCIe link. The

following encodings are defined:
• 2b’00: Undefined

• 2b’01: Gen1

• 2b’10: Gen2

• 2b’11: Gen3

14'h3C6C

lane_act_reg[3:0]

O

Lane Active Mode: This signal indicates the number

of lanes that configured during link training. The

following encodings are defined:
• 4’b0001: 1 lane

• 4’b0010: 2 lanes

• 4’b0100: 4 lanes

• 4’b1000: 8 lanes

Programming Model for Avalon‑MM Root Port

The Application Layer writes the Root Port TLP TX Data registers with TLP formatted data for Configu‐

ration Read and Write Requests, Message TLPs, I/O Read and Write Requests, or single dword Memory

Read and Write Requests. Software should check the Root Port

Link Status

register (offset 0x92) to

ensure the Data Link Layer Link

Active

bit is set to 1'b1 before issuing a Configuration request to

downstream ports.
The Application Layer data must be in the appropriate TLP format with the data payload aligned to the

TLP address. Aligning the payload data to the TLP address may result in the payload data being either

aligned or unaligned to the qword. The following figure illustrates three dword TLPs with data that is

aligned and unaligned to the qword.

5-26

Programming Model for Avalon‑MM Root Port

UG-01105_avmm

2014.12.15

Altera Corporation

Registers

Send Feedback

Advertising
This manual is related to the following products: