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Hawk PCI Host Bridge & Multi-Processor Interrupt Controller
2
MEM PCI Memory Cycle. If set, the corresponding PPC Slave
will generate transfers to or from PCI memory space.
When clear, the corresponding PPC Slave will generate
transfers to or from PCI I/O space using the addressing
mode defined by the IOM field.
IOM PCI I/O Mode. If set, the corresponding PPC Slave will
generate PCI I/O cycles using spread addressing as
defined in the section titled Generating PCI Cycles. When
clear, the corresponding PPC Slave will generate PCI I/O
cycles using contiguous addressing. This field only has
meaning when the MEM bit is clear.
PPC Slave Address (3) Register
The PPC Slave Address Register 3 (XSADD3) contains address
information associated with the mapping of PPC memory space to PCI I/O
space. XSADD3 (in conjunction with XSOFF3/XSATT3) is the only
register group that can be used to initiate access to the PCI
CONFIG_ADDRESS ($80000CF8) and CONFIG_DATA ($80000CFC)
registers. The power up value of XSADD3 (and XSOFF3/XSATT3) are
set to allow access to these special register spaces without PPC register
initialization.
Address MSADD3 - $FEFF0058
Bit 01234567891
01
11
21
31
41
51
61
71
81
92
02
12
22
32
42
52
62
72
82
93
03
1
Name XSADD3
START END
Operation R/W R/W
Reset Regbase 0xfeff0000 => $8000
Regbase 0xfefe0000 => $9000 Regbase 0xfeff0000 => $8080
Regbase 0xfefe0000 => $9080