cx28560 Mindspeed Technologies, cx28560 Datasheet - Page 51

• Manufacturer Part Number: cx28560
• Description: Hdlc Controller
• Manufacturer: Mindspeed Technologies

CX28560 Data Sheet
2.1.1.4
28560-DSH-001-B
PCI Configuration Space
This section describes how the CX28560 implements the required PCI configuration
register space. The intent of PCI configuration space definition is to provide an
appropriate set of configuration registers that satisfy the needs of current and
anticipated system configuration mechanisms, without specifying those mechanisms
or otherwise placing constraints on their use. These registers allow for the following:
The CX28560 responds only to Type 0 configuration cycles. Type 1 cycles, which
pass a configuration request on to another PCI bus, are ignored.
The CX28560 is a single function PCI agent; therefore, it implements configuration
space for Function 0 only.
The PCI controller in the CX28560 responds to configuration and memory cycles, but
only memory cycles cause bus activity on the EBUS.
The address phase during a the CX28560 configuration cycle indicates the function
number and register number being addressed, which can be decoded by observing the
status of the address lines AD[31:0]. The figure below illustrates the address lines
during configuration cycle.
The value of the signal lines AD[10:8] selects the function being addressed. Since the
CX28560 supports Function 0 only, it ignores these bits. The value of the signal lines
AD[7:2] during the address phase of configuration cycles selects the register of the
configuration space to access. Valid values are 0 through 15. Accessing registers
outside this range results in an all 0s value being returned on reads, and no action
being taken on writes.
The value of the signal lines AD[1:0] must be 00b for the CX28560 to respond. If
these bits are 0 and the IDSEL* signal line is asserted, then the CX28560 responds to
the configuration cycle.
NOTE(S):
The CX28560 supports registers 0 through 15 inclusively
The CX28560 supports Type 0 configuration cycles.
31
• Full device relocation, including interrupt binding
• Installation, configuration, and booting without user intervention
• System address map construction by device-independent software
Don’t Care
The CX28560 supports Function 0 only
Mindspeed Technologies™
8
Advance Information
7
6 bit register #
2
1
2 bit Type #
0
Host Interfaces
2
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5