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Base address registers for function

Page 60: Base and limit registers for root port func

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Chapter 4: Parameter Settings for the Arria V Hard IP for PCI Express

Port Functions

Arria V Hard IP for PCI Express

December 2013

Altera Corporation

User Guide

1

When you click on a Func tab, the parameter settings automatically relate to the
function currently selected.

Base Address Registers for Function

Table 4–7

describes the Base Address (BAR) register parameters.

Base and Limit Registers for Root Port Func

If you specify a Root Port for function 0, the settings for Base and Limit Registers
required by Root Ports appear after the Base Address Register heading. These
settings are stored in the Type 1 Configuration Space for Root Ports. They are used for
TLP routing and specify the address ranges assigned to components that are
downstream of the Root Port or bridge. Function 0 is the only function that provides
the Root Port option for Port type.

f

For more information, refer to the

PCI-to-PCI Bridge Architecture Specification

.

Table 4–7. Func0–Func7 BARs and Expansion ROM

Parameter

Value

Description

Type

0x010

,

0x014

,

0x018

,

0x01C

,

0x020

,

0x024

Disabled

64-bit prefetchable memory

32-bit non-prefetchable memory

32-bit prefetchable memory

I/O address space

If you select 64-bit prefetchable memory, 2 contiguous BARs are
combined to form a 64-bit prefetchable BAR; you must set the
higher numbered BAR to Disabled. A non-prefetchable 64-bit BAR
is not supported because in a typical system, the Root Port Type 1
Configuration Space sets the maximum non-prefetchable memory
window to 32-bits. The BARs can also be configured as separate
32-bit prefetchable or non-prefetchable memories.

The I/O address space BAR is only available for the Legacy
Endpoint
.

Size

16 Bytes–8 EBytes

The Endpoint and Root Port variants support the following memory
sizes:

×1, ×2, ×4: 128 bytes–2 GBytes or 8 EBytes

×8: 4 KBytes–2 GBytes or 8 EBytes (2 GBytes for 32-bit
addressing and 8 EBytes for 64-bit addressing)

The Legacy Endpoint supports the following I/O space BARs:

×1, ×2, ×4:16 bytes–4 KBytes

×8: 4 KBytes

Expansion ROM

Size

Disabled

4 KBytes–16 MBytes

Specifies the size of the optional ROM.