Chapter 7: Register Descriptions
7–17
PCI Express Avalon-MM Bridge Control Register Access Content
November 2012
Altera Corporation
Arria V GZ Hard IP for PCI Express
1
The high performance TLPs implemented by Avalon-MM ports in the Avalon-MM
Bridge are also available for Root Ports. For more information about these TLPs, refer
to
.
describes the Root Port TLP data registers.
Programming Model for Avalon-MM Root Port
The Application Layer writes the Root Port TLP TX Data registers with TLP formatted
data for Configuration Read and Write Requests, I/O Read and Write Requests, or
single dword Memory Read and Write Requests. 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.
illustrates three dword TLPs
with data that is aligned and unaligned to the qword.
Table 7–32. Root Port TLP Data Registers
0x2000–0x2FFF
Root-Port Request Registers
Address Range: 0x2800-0x2018
Address
Bits
Name
Access
Description
0x2000
[31:0]
RP_TX_REG0
RW
Lower 32 bits of the TX TLP.
0x2004
[31:0]
RP_TX_REG1
RW
Upper 32 bits of the TX TLP.
0x2008
[31:2]
Reserved
—
—
[1]
RX_TX_CNTRL.SOP
RW
Write 1’b1 to specify the start of a packet.
[0]
RX_TX_CNTRL.EOP
RW
Write 1’b1 to specify the end of a packet.
0x2010
[31:16]
Reserved
—
—
[15:8]
RP_RXCPL_STATUS
RC
Specifies the number of words in the RX
completion FIFO contain valid data.
[7:2]
Reserved
—
—
[1]
RP_RXCPL_STATUS.SOP
RC
When 1’b1, indicates that the data for a
Completion TLP is ready to be read by the
Application Layer. The Application Layer must poll
this bit to determine when a Completion TLP is
available.
[0]
RP_RXCPL_STATUS.EOP
RC
When 1’b1, indicates that the final data for a
Completion TLP is ready to be read by the
Application Layer. The Application Layer must poll
this bit to determine when the final data for a
Completion TLP is available.
0x2014
[31:0]
RP_RXCPL_REG0
R
Lower 32 bits of a Completion TLP.
0x2018
[31:0]
RP_RXCPL_REG1
R
Upper 32 bits of a Completion TLP.