Ppc Slave Offset/Attribute (3) Registers - Motorola MVME5100 Programmer's Reference Manual

Hawk PCI Host Bridge & Multi-Processor Interrupt Controller
2

PPC Slave Offset/Attribute (3) Registers

Address
Bit
Name
Operation
Reset
2-90
The fields within XSADD3 are defined as follows:
START Start Address. This field determines the start address of
a particular memory area on the PPC bus which will be
used to access PCI bus resources. The value of this field
will be compared with the upper 16 bits of the incoming
PPC address.
END End Address. This field determines the end address of a
particular memory area on the PPC bus which will be used
to access PCI bus resources. The value of this field will be
compared with the upper 16 bits of the incoming PPC
address.
XSOFF3/XSATT3 - $FEFF005C
XSOFF3
R/W
Regbase 0xfeff0000 => $8000
Regbase 0xfefe0000 => $7000
The PPC Slave Offset Register 3 (XSOFF3) contains offset information
associated with the mapping of PPC memory space to PCI I/O space. The
field within the XSOFF3 register is defined as follows:
XSOFFx PPC Slave Offset. This register contains a 16-bit offset
that is added to the upper 16 bits of the PPC address to
determine the PCI address used for transfers from the PPC
bus to PCI. This offset allows PCI resources to reside at
addresses that would not normally be visible from the
PPC bus. It is initialized to $8000 to facilitate a zero based
access to PCI space.
R
$00
Computer Group Literature Center Web Site
XSATT3