Completer only single dword endpoint, Completer only single dword endpoint -19 – Altera Arria 10 Avalon-MM User Manual
Page 137

Figure 10-10: Avalon-MM-to-PCI Express Address Translation
The following figure depicts the Avalon-MM-to-PCI Express address translation process. In this figure
the variables represent the following paramers:
• N—the number of pass-through bits.
• M—the number of Avalon-MM address bits.
• P—the number of PCIe address bits.
• Q—the number of translation table entries.
•
Sp[1:0]
—the space indication for each entry.
PCIe Address Q-1
SpQ-1
Space Indication
PCI Express address from Table Entry
becomes High PCI Express address bits
PCI Express Address
High
Low
P-1
N N-1
0
Low address bits unchanged
Avalon-MM-to-PCI Express
Address Translation Table
(Q entries by P-N bits wide)
PCIe Address 0
Sp0
PCIe Address 1
Sp1
Avalon-MM Address
High
Slave Base
Address
Low
M-1
31
M
N N-1
0
Table updates from
control register port
High Avalon-MM Address
Bits Index table
Completer Only Single Dword Endpoint
The completer only single dword endpoint is intended for applications that use the PCI Express protocol
to perform simple read and write register accesses from a host CPU. The completer only single dword
endpoint is a hard IP implementation available for Qsys systems, and includes an Avalon-MM interface to
the Application Layer. The Avalon-MM interface connection in this variation is 32 bits wide. This
endpoint is not pipelined; at any time a single request can be outstanding.
The completer-only single dword endpoint supports the following requests:
• Read and write requests of a single dword (32 bits) from the Root Complex
• Completion with Completer Abort status generation for other types of non-posted requests
• INTX or MSI support with one Avalon-MM interrupt source
UG-01145_avmm
2015.05.14
Completer Only Single Dword Endpoint
10-19
IP Core Architecture
Altera Corporation