PLB PCI Full Bridge (v1.00a)
DS508 March 21, 2006
www.xilinx.com
33
Product Specification
EAR
LY
ACCESS
For all the transactions listed above, the following design requirements are specified:
• Both PCI and PLB clocks will be independent global buffers. For Virtex-4, RCLK must also be
driven by global buffer.
• The PLB clock can be slower or faster than the PCI clock. For Virtex-4, RCLK must be 200 MHz.
• Address space on the PCI side accessible from the PLB side must be translated to a 2
N
contiguous
block on the PLB side. Up to six independent blocks are possible. Each block has parameters for
base address (BAR), high address which must define a 2
N
range, address translation vector, and
memory designator (memory or I/O).
• All address space on the PLB side that is accessible from the PCI side must be translated to a
maximum of three 2
N
contiguous blocks on the PCI side. Up to three independent blocks are
possible because the LogiCore PCI v3.0 core supports up to 3 BARs. Each block has parameters for
length which must be a 2
N
range, and address translation vector. Only memory space in the sense
of PCI memory space is supported. Space type is mirrored in the PCI configuration registers.
Sequential Read, 4, 8 and
16-word cacheline read
(1)
I/O Read
Memory Read Multiple
Not Supported
Single Write (<=8 bytes)
I/O Write
Memory Write
Not Supported
Write Burst transfer double
word
I/O Write
Memory Write (multiple
data phase)
Not Supported
Sequential fill, 4, 8 and
16-word cacheline write
(2)
I/O Write
Memory Write (multiple
data phase)
Not Supported
Notes:
1. The PLB IPIF aligns the address on the IPIC to a double word boundary which is then presented on the PCI
bus. This is independent of the target word presented.
2. The 405 always sources the first word on the line (i.e., sequential fill) on write.
Table 16:
Translation Table for PCI commands to PLB transactions
PCI Initiator Command
PLB Memory Prefetchable
PLB Memory Non-prefetchable
I/O Read
Not Supported
Not Supported
I/O Write
Not Supported
Not Supported
Memory Read
PLB Single Read
Not Supported
Memory Read Multiple
PLB Burst Read with all BE asserted
(1)
Not Supported
Memory Read Line
PLB Single Read
Not Supported
Memory Write
(single data phase)
PLB Single Write
Not Supported
Memory Write
2
(multiple data phase)
PLB Burst Write of length defined by
available data in FIFO
(2)
Not Supported
Memory Write Invalidate
PLB Burst Write
Not Supported
Notes:
1. The PLB does not support dynamic byte enable (BE) in burst read transactions so when Memory Read Multiple
is translated to a PLB burst read, all BE are asserted during the PLB read operation.
2. The PLB does not support dynamic byte enable (BE) in burst write transactions so when Memory Write Multiple
is translated to a PLB burst write, all BE are asserted during the PLB write operation.
Table 15:
Translation Table for PLB transactions to PCI commands
(Contd)