Intel Intel Gigabit Ethernet Controllers manual Microarchitecture, 1 PCI/PCI-X Core Interface

Architectural Overview

2.3Microarchitecture

Compared to its predecessors, the PCI/PCI-X Family of Gigabit Ethernet Controller’s MAC adds improved receive-packet filtering to support SMBus-based manageability, as well as the ability to transmit SMBus-based manageability packets. In addition, an ASF-compliant TCO controller is integrated into the controller’s MAC for reduced-cost basic ASF manageability.

Note: The 82544GC/EI and 82541ER do not support SMBus-based manageability.

For the 82546GB/EB, this new functionality is packaged in an integrated dual-port combination. The architecture includes two instances of both the MAC and PHY along with a single PCI/PCI-X interface. As a result, each of the logical LAN devices appear as a distinct PCI/PCI-X bus device.

The following sections describe the hardware building blocks. Figure 2-4shows the internal microarchitecture.

2.3.1PCI/PCI-X Core Interface

The PCI/PCI-X core provides a complete glueless interface to a 33/66 MHz, 32/64-bit PCI bus or a 33/66/133 MHz, 32/64 bit PCI-X bus. It is compliant with the PCI Bus Specification Rev 2.2 or 2.3 and the PCI-X Specification Rev. 1.0a. The Ethernet controllers provide 32 or 64 bits of addressing and data, and the complete control interface to operate on a 32-bit or 64-bit PCI or PCI-X bus. In systems with a dedicated bus for the Ethernet controller, this provides sufficient bandwidth to support sustained 1000 Mb/s full-duplex transfer rates. Systems with a shared bus (especially the 32-bit wide interface) might not be able to maintain 1000 Mb/s, but can sustain multiple hundreds of Mbps.

PCI Interface

PCI/

PCI-X

Core

Host Arbiter

				TX	TX MAC
					(10/100/
				Switch
DMA					1000 Mb)
Engine
					RX MAC
			Packet/		(10/100/
					1000 Mb)
			Manageability
			Filter
Packet	ASF
Buffer	Manageability				RMON
					Statistics
		SM Bus

GMII/

MII

MDIO

Link I/F

MDIO

EEPROM Flash

Figure 2-4. Internal Architecture Block Diagram

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