Stratix V Avalon-ST Interface with SR-IOV PCIe Solutions: User Guide

ID 683488
Date 5/02/2016
Public
Document Table of Contents

5.15.7. VF Base Address Registers (BARs) 0-5

Each PF implements six BARs. You can specify BAR settings in Platform Designer. You can configure VF BARs as 32-bit memories. Or you can combine VF BAR0 and BAR1 to form a 64-bit memory BAR. VF BAR 0 may also be designated as prefetchable or non-prefetchable in Platform Designer. Finally, the address range of VF BAR 0 can be configured as any power of 2 between 128 bytes and 2 GB.

The contents of VF BAR 0 are described below:

Table 81.  VF BARs 0-5 - 0x264 - 0x270

Bits

Register Description

Default Value

Access

[0] Memory Space Indicator: Hardwired to 0 to indicate the BAR defines a memory address range. 0 RO
[1] Reserved. Hardwired to 0. 0
[2] Specifies the BAR size.: The following encodings are defined:
  • 1'b0: 32-bit BAR
  • 1'b1: 64-bit BAR created by pairing BAR0 with BAR1, BAR2 with BAR3, or BAR4 with BAR5

0

RO
[3] When 1, indicates that the data within the address range refined by this BAR is prefetchable. When 1, indicates that the data is not prefetchable. Data is prefetchable if reading is guaranteed not to have side-effects . Prefetchable: 0

Non-Prefetchable: 1

RO
[7:4] Reserved. Hardwired to 0. 0 RO

[31:8]

Base address of the BAR. The number of writable bits is based on the BAR access size. For example, if bits [15:8] are hardwired to 0, if the BAR access size is 64 KB. Bits [31:16] can be read and written.

0

See description