PCI Configuration Registers
BCM5718 Programmer’s Guide
Broadcom
®
January 29, 2016 • 5718-PG108-R
Page 275
Base Address Register 4 (offset: 0x1c)
Base Address Register 5 (offset: 0x20)
The 32-bit BAR_5 register programs the 3rd base address for the memory space mapped by the card onto the
PCI bus. This register can be combined with BAR_4 to make a 64-bit address for supporting Dual Address
cycles systems.This register is not needed by Xinan and is expected to be disabled. The register is used by
Everest which requires a 2nd BAR. Path = i_cfg_func.i_cfg_public.i_cfg_dec.
Base Address Register 6 (offset: 0x24)
The 32-bit BAR_4 register programs the upper half of the 3nd base address for the memory space mapped by
the card onto the PCI bus.
Name
Bits
Access
Default
Value
Description
Address
31:0
RW
0
These bits set the address upper 32-bit address space.
These bits may be combined with the bits in BAR_2 to create
a full 64 bit address decode. These bits must be set to zero
for the card to respond to single address cycle requests. This
value is sticky and only reset by HARD Reset.
Name
Bits
Access
Default
Value
Description
Address
31:4
RW
0
These bits set the address within a 32-bit address space that
will be card will respond in. These bits may be combined with
the bits in BAR_6 to create a full 64 bit address decode. Only
the bits that address blocks bigger than the setting in the
BAR3_SIZE value are RW. All lower bits are RO with a value
of zero. This value is sticky and only reset by HARD Reset.
Prefetch
3
RO
0x1
This bit indicates that the area mapped by BAR_3 may be
pre-fetched or cached by the system without side effects.
Path = i_cfg_func.i_cfg_private.
Type
2:1
RO
0x2
These bits indicate that BAR_3 may be programmed to map
this adapter to anywhere in the 64-bit address space. Path =
i_cfg_func.i_cfg_private.
Space
0
RO
0
This bit indicates that BAR_3 maps a memory space and is
always read as 0. Path = i_cfg_func.i_cfg_private
Name
Bits
Access
Default
Value
Description
Address
31:0
RW
0
These bits set the address upper 32-bit address space These
bits may be combined with the bits in BAR_5 to create a full
64 bit address decode. These bits must be set to zero for the
card to respond to single address cycle requests. This value
is sticky and only reset by HARD Reset. Path =
i_cfg_func.i_cfg_public.i_cfg_dec.