Master and target performance, Master performance, Target performance – Altera Embedded Peripherals IP User Manual
Page 139: Master and target performance -5

Table 14-3: Avalon-to-PCI Address Translation Table – Address Range: 0x1000-0x1FFF
Address
Bit
Name
Access
Mode
Description
0x10
00
1:0
A2P_ADDR_SPACE0
W
Address space indication for entry 0. See
Address Space Bit Encodings table for the
definition of these bits.
31:2
A2P_ADDR_MAP_LO0
W
Lower bits of Avalon-to-PCI address map entry
0. The pass through bits are not writable and are
forced to 0.
0x10
04
31:0
A2P_ADDR_MAP_HI0
W
Reserved.
0x10
08
1:0
A2P_ADDR_SPACE1
W
Address Space indication for entry 1. See
Address Space bit Encodings for the definition
of these bits.
31:2
A2P_ADDR_MAP_LO1
W
Lower bits of Avalon-to-PCI address map entry
1. Pass through bits are not writable and are
forced to 0.
This entry is only implemented if the number of
pages in the address translation table is greater
than 1.
0x10
0C
31:0
A2P_ADDR_MAP_HI1
W
Reserved.
Master and Target Performance
The performance of the PCI Lite core is designed to provide low-latency single-cycle and burst
transactions.
Master Performance
The master provides high throughput for transactions initiated by Avalon-MM master devices to PCI
target devices via the PCI bus master interface. Avalon-MM read transactions are implemented as latent
read transfers. The PCI master device issues only one read transaction at a time.
The PCI bus access (PBA) handles the Avalon master transaction system interconnect hold state for 6
clock cycles. This is the maximum number of cycles supported by the PCI specification.
Target Performance
The target allows high throughput read/write operations to Avalon-MM slave peripherals. Read/write
accesses to prefetchable base address registers (BARs) use dual-port buffers to enable burst transactions
on both the PCI and Avalon-MM sides. This profile also allows access to the PCI BARs (Prefetchable,
Non-Prefetchable, and I/O) to use their respective Avalon-MM master ports to initiate transfers to
Avalon-MM slave peripherals. Prefetchable handles burst transaction and Non-Prefetchable and I/O
handles only single-cycle transaction.
UG-01085
2014.24.07
Master and Target Performance
14-5
PCI Lite Core
Altera Corporation