Texas Instruments PCI7411, PCI7611 Power-Management Data Register, Power-management data, Bpccen

4.45 Power Management Control/Status Bridge Support Extensions Register

This register supports PCI bridge-specific functionality. It is required for all PCI-to-PCI bridges. See Table 4−21 for a complete description of the register contents.

Bit	7		6		5	4	3	2	1	0
Name					Power management control/status bridge support extensions
Type		R	R		R	R	R	R	R	R
Default	1		1		0	0	0	0	0	0
	Register:		Power management control/status bridge support extensions
	Offset:		A6h (Functions 0, 1)
	Type:		Read-only
	Default:		C0h
Table 4−21. Power Management Control/Status Bridge Support Extensions Register Description
BIT	SIGNAL		TYPE				FUNCTION
				Bus power/clock control enable. This bit returns 1 when read. This bit is encoded as:
				0 = Bus power/clock control is disabled.
				1 = Bus power/clock control is enabled (default).
7	BPCC_EN		R	A 0 indicates that the bus power/clock control policies defined in the PCI Bus Power Management Interface
				Specification are disabled. When the bus power/clock control enable mechanism is disabled, the power
				state field (bits 1−0) of the power management control/status register (PCI offset A4h, see Section 4.44)
				cannot be used by the system software to control the power or the clock of the secondary bus. A 1 indicates
				that the bus power/clock control mechanism is enabled.
				B2/B3 support for D3hot. The state of this bit determines the action that is to occur as a direct result of
				programming the function to D3hot. This bit is only meaningful if bit 7 (BPCC_EN) is a 1. This bit is encoded
				as:
6	B2_B3		R
				0 = When the bridge is programmed to D3hot, its secondary bus has its power removed (B3).
				1 = When the bridge function is programmed to D3hot, its secondary bus PCI clock is stopped (B2)
					(default).
5−0		RSVD	R	Reserved. These bits return 0s when read.

4.46 Power-Management Data Register

The power-management data register returns 0s when read, because the CardBus functions do not report dynamic data.

Bit	7	6	5	4	3	2	1	0
Name				Power-management data
Type	R	R	R	R	R	R	R	R
Default	0	0	0	0	0	0	0	0
	Register:	Power-management data
	Offset:	A7h (functions 0, 1)
	Type:	Read-only
	Default:	00h

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