Xilinx PLB PCI Full Bridge specifications Host Bridge Device Number Register Description

PLB PCI Full Bridge (v1.00a)

Writing 0xFEDC0000 to IPIFBAR2PCIBAR_1 High-Order Bit Register and then accessing the PLB PCI bridge IPIFBAR_1 with address 0xABCDF123 on the PLB bus would yield 0xFEDC1123 on the PCI bus.

Writing 0x40000000 to IPIFBAR2PCIBAR_2 High-Order Bit Register and then accessing the PLB PCI bridge IPIFBAR_2 with address 0xFFFEDCBA on the PLB bus would yield 0x41FEDCBA on the PCI bus.

Writing 0x12345680 to IPIFBAR2PCIBAR_3 High-Order Bit Register and then accessing the PLB PCI bridge IPIFBAR_3 with address 0x0000004A on the PLB bus would yield 0x123456CA on the PCI bus.

Host Bridge Device Number Register Description

The Host Bridge Device Number register is included by setting C_INCLUDE_DEVNUM_REG=1. The register can be included only if configuration functionality is included (i.e., C_INCLUDE_PCI_CONFIG=1).

This register is read/write and is four bits wide. Table 14 shows specifics of the data format. The programmability of this register allows programmable definition of the bridge device number and corresponding address bit that is internally connected to its IDSEL signal. The maximum value that can be loaded in this register is given by the value set by parameter C NUM IDSEL minus 1 because the device number must be consistent with the number of devices that are supported in configuation transactions.

Table 14: Host Bridge Device Number (Bit assignment assumes 32-bit bus)

Bit(s)	Name	Access	Reset	Description
			Value
0-27	D0-D27	Read Only	0x0	Set to zero.
28-31	D28 - D31	Read/Write	0x0	Defines the device number of the PLB PCI bridge when
				configured as a Host Bridge.

DS508 March 21, 2006 www.xilinx.com 31

Product Specification