Physical Function BAR Configuration Register 1 @0x244

This register specifies the configuration of the BARs associated with the Physical Function.

Table 1. i_pf_0_BAR_config_1_reg
Bits SW Name Description Reset
4:0 R/W BAR 4 Aperture [BAR4A] Specifies the aperture of the 32-bit BAR 4 or 64-bit BAR 4-5.
For 32-bit BAR 4, the valid encodings are:
  • 00000 = 128 B
  • 00001 = 256 B
  • 00010 = 512 B
  • 00011 = 1 KB
  • 00100 = 2 KB
  • 00101 = 4 KB
  • 00110 = 8 KB
  • 00111 = 16 KB
  • 01000 = 32 KB
  • 01001 = 64 KB
  • 01010 = 128 KB
  • 01011 = 256 KB
  • 01100 = 512 KB
  • 01101 = 1 MB
  • 01110 = 2 MB
  • 01111 = 4 MB
  • 10000 = 8 MB
  • 10001 = 16 MB
  • 10010 = 32 MB
  • 10011 = 64 MB
  • 10100 = 128 MB
  • 10101 = 256 MB
  • 10110 = 512 MB
  • 10111 = 1 GB
  • 11000 = 2 GB
(continued on next page)
 5'h5
BAR 4 Aperture [BAR4A]
(continued)
 For 64-bit BAR 4-5, the valid encodings are:
  • 00000 = 128 B
  • 00001 = 256 B
  • 00010 = 512 B
  • 00011 = 1 KB
  • 00100 = 2 KB
  • 00101 = 4 KB
  • 00110 = 8 KB
  • 00111 = 16 KB
  • 01000 = 32 KB
  • 01001 = 64 KB
  • 01010 = 128 KB
  • 01011 = 256 KB
  • 01100 = 512 KB
  • 01101 = 1 MB
  • 01110 = 2 MB
  • 01111 = 4 MB
  • 10000 = 8 MB
  • 10001 = 16 MB
  • 10010 = 32 MB
  • 10011 = 64 MB
  • 10100 = 128 MB
  • 10101 = 256 MB
  • 10110 = 512 MB
  • 10111 = 1 GB
  • 11000 = 2 GB
  • 11001 = 4 GB
  • 11010 = 8 GB
  • 11011 = 16 GB
  • 11100 = 2 GB
  • 11101 = 64 GB
  • 11110 = 128 GB
  • 11111 = 256 GB
7:5 R/W BAR 4 Control [BAR4C] Specifies the configuration of BAR 4. The various encodings are:
  • 000: Disabled
  • 001: 32-bit I/O BAR
  • 010–011: Reserved
  • 100: 32-bit memory BAR, non-prefetchable
  • 101: 32-bit memory BAR, prefetchable
  • 110: 64-bit memory BAR, non-prefetchable
  • 111: 64-bit memory BAR, prefetchable
 3'h0
12:8 R/W BAR 5 Aperture [BAR5A] Specifies the aperture of the BAR 5 when it is configured as a 32-bit BAR. For 32-bit BAR 5, the valid encodings are:
  • 00000 = 128 B
  • 00001 = 256 B
  • 00010 = 512 B
  • 00011 = 1 KB
  • 00100 = 2 KB
  • 00101 = 4 KB
  • 00110 = 8 KB
  • 00111 = 16 KB
  • 01000 = 32 KB
  • 01001 = 64 KB
  • 01010 = 128 KB
  • 01011 = 256 KB
  • 01100 = 512 KB
  • 01101 = 1 MB
  • 01110 = 2 MB
  • 01111 = 4 MB
  • 10000 = 8 MB
  • 10001 = 16 MB
  • 10010 = 32 MB
  • 10011 = 64 MB
  • 10100 = 128 MB
  • 10101 = 256 MB
  • 10110 = 512 MB
  • 10111 = 1 GB
  • 11000 = 2 GB
 5'h5
15:13 R/W BAR 5 Control [BAR5C] Specifies the configuration of BAR 5. The various encodings are:
  • 000: Disabled
  • 001: 32-bit I/O BAR
  • 010–011: Reserved
  • 100: 32-bit memory BAR, non-prefetchable
  • 101: 32-bit memory BAR, prefetchable
  • 110–111: Reserved
 3'h0
20:16 R/W EXP-ROM BAR Aperture [ERBA] Specifies the aperture of the Expansion ROM BAR. The encodings are:
  • 00000–00011 = undefined
  • 00100 = 2 KB
  • 00101 = 4 KB
  • 00110 = 8 KB
  • 00111 = 16 KB
  • 01000 = 32 KB
  • 01001 = 64 KB
  • 01010 = 128 KB
  • 01011 = 256 KB
  • 00110 = 512 KB
  • 01101 = 1 MB
  • 01110 = 2 MB
  • 01111 = 4 MB
  • 10000 = 8 MB
  • 10001 = 16 MB
  • 10010–11111 = undefined
 5'h5
21 R/W EXP-ROM BAR Enable [ERBE] This bit must be set to enable the Expansion ROM BAR associated with the Function. 0x01
23:22 R Reserved [R22] Reserved 0x0
30:24 R Reserved [R24] Reserved 0x0
31 R/W Enable Resizable BAR Capability [ERBC] Setting this bit to 1 enables the Resizable BAR Capability in the PCI Express Configuration Space of the associated Function. When the Resizable BAR Capability is enabled, the apertures of the memory BARs of the corresponding Function are no longer selected by the fields in this register, but by the setting of the registers in the Resizable BAR Capability Structure. 0x0