Texas Instruments PCI7411, PCI7611 Power Management Overview, Using Serialized Irqser Interrupts

The INTRTIE and TIEALL bits affect the read-only value provided through accesses to the interrupt pin register (PCI offset 3Dh, see Section 4.24). Table 3−12 summarizes the interrupt signaling modes.

Table 3−12. Interrupt Pin Register Cross Reference

INTRTIE

TIEALL

INTPIN

INTPIN

INTPIN

INTPIN

INTPIN

INTPIN

Function 0

Function 1

Function 2

Function 3

Function 4

Function 5

Bit

Bit

(CardBus)

(CardBus)

(1394 OHCI)

(Flash Media)

(SD Host)

(Smart Card)

Determined by bits

Determined by bits

Determined by bits

0

0

0x01 (INTA)

0x02 (INTB)

0x03 (INTC)

6−5 (INT_SEL field) in

6−5 (INT_SEL field) in

6−5 (INT_SEL field) in

flash media general

SD host general

Smart Card general

control register (see

control register (see

control register (see

1

0

0x01 (INTA)

0x01 (INTA)

0x03 (INTC)

Section 11.21)

Section 12.22)

Section 13.22)

X

1

0x01

0x01

0x01

0x01

0x01

0x01

(INTA)

(INTA)

(INTA)

(INTA)

(INTA)

(INTA)

3.7.5Using Serialized IRQSER Interrupts

The serialized interrupt protocol implemented in the PCI7x21/PCI7x11 controller uses a single terminal to communicate all interrupt status information to the host controller. The protocol defines a serial packet consisting of a start cycle, multiple interrupt indication cycles, and a stop cycle. All data in the packet is synchronous with the PCI clock. The packet data describes 16 parallel ISA IRQ signals and the optional 4 PCI interrupts INTA, INTB, INTC, and INTD. For details on the IRQSER protocol, refer to the document Serialized IRQ Support for PCI Systems.

3.7.6SMI Support in the PCI7x21/PCI7x11 Controller

The PCI7x21/PCI7x11 controller provides a mechanism for interrupting the system when power changes have been made to the PC Card socket interfaces. The interrupt mechanism is designed to fit into a system maintenance interrupt (SMI) scheme. SMI interrupts are generated by the PCI7x21/PCI7x11 controller, when enabled, after a write cycle to either the socket control register (CB offset 10h, see Section 6.5) of the CardBus register set, or the ExCA power control register (ExCA offset 02h/42h/802h, see Section 5.3) causes a power cycle change sequence to be sent on the power switch interface.

The SMI control is programmed through three bits in the system control register (PCI offset 80h, see Section 4.29). These bits are SMIROUTE (bit 26), SMISTATUS (bit 25), and SMIENB (bit 24). Table 3−13 describes the SMI control bits function.

	Table 3−13. SMI Control
BIT NAME	FUNCTION
SMIROUTE	This shared bit controls whether the SMI interrupts are sent as a CSC interrupt or as IRQ2.
SMISTAT	This socket-dependent bit is set when an SMI interrupt is pending. This status flag is cleared by writing back a 1.
SMIENB	When set, SMI interrupt generation is enabled. This bit is shared by functions 0 and 1.

If CSC SMI interrupts are selected, then the SMI interrupt is sent as the CSC on a per-socket basis. The CSC interrupt can be either level or edge mode, depending upon the CSCMODE bit in the ExCA global control register (ExCA offset 1Eh/5Eh/81Eh, see Section 5.20).

If IRQ2 is selected by SMIROUTE, then the IRQSER signaling protocol supports SMI signaling in the IRQ2 IRQ/Data slot. In a parallel ISA IRQ system, the support for an active low IRQ2 is provided only if IRQ2 is routed to either MFUNC3 or MFUNC6 through the multifunction routing status register (PCI offset 8Ch, see Section 4.36).

3.8 Power Management Overview

In addition to the low-power CMOS technology process used for the PCI7x21/PCI7x11 controller, various features are designed into the controller to allow implementation of popular power-saving techniques. These features and techniques are as follows:

•Clock run protocol

•Cardbus PC Card power management

•16-bit PC Card power management

•Suspend mode

3−20