Initialization

Range —Specifies the PCI Address bits to use for decoding a PCI access to Local Bus space. Each bit corresponds to a PCI Address bit. Bit 31 corresponds to address bit 31. Write 1 to all bits required to be included in decode, and 0 to all others.

Remap PCI-to-Local Addresses into a Local Address Space —Bits in this register remap (replace) the PCI Address bits used in decode as the Local Address bits.

Local Bus Region Descriptor —Specifies the Local Bus characteristics.

PCI Target Initialization

After a PCI reset and serial EEPROM load, the software determines the amount of required address space by writing all ones (1) to a PCI Base Address register and then reading back the value. The PCI 9030 returns zeros (0) in the Don’t Care Address bits, effectively specifying the address space required, at which time the PCI software maps the Local Address space into the PCI Address space by programming the PCI Base Address register. (Refer to Figure 4-5.)

PCI Bus Master

2

Initialize PCI

Base Address Registers

Serial EEPROM

Local Address Space 0, 1, 2, and 3 Ranges

Local Address Space 0, 1, 2, and 3 Local Base Addresses (Remap)

Local Address Space 0, 1, 2, and 3 Bus Region Descriptors

Initialize Local Direct Access Registers

Expansion ROM Range

Expansion ROM Local Base Address (Remap)

Expansion ROM Bus Region Descriptor

Local Bus Hardware Characteristics

PCI Base Addresses for Accesses to Local Address Space 0, 1, 2, and 3

PCI Expansion ROM Base Address

FIFOs 32-Lword Deep Write 16-Lword Deep Read

3 4

PCI Bus

Access

Local Bus Access

PCI Address Space

PCI Base Address

Local Base Address

Local Memory

Range

Дата добавления: 2015-07-10