Compaq EV68A Dstream TB Invalidate All Process ASM=0 Register Dtbiap, ALTMODE10, Mode

Mbox IPRs

Table 5–17 DTB Alternate Processor Mode Register Fields Description (Continued)

Name	Extent	Type	Description
ALT_MODE[1:0]	[1:0]	WO	Alt_Mode:
			ALT_MODE[1:0]	Mode
			00	Kernel
			01	Executive
			10	Supervisor
			11	User

5.3.4 Dstream TB Invalidate All Process (ASM=0) Register – DTB_IAP

The Dstream translation buffer invalidate all process (ASM=0) register (DTB_IAP) is a write-only pseudo register. Write transactions to this register invalidate all DTB entries in which the address space match (ASM) bit is clear.

5.3.5 Dstream TB Invalidate All Register – DTB_IA

The Dstream translation buffer invalidate all register (DTB_IA) is a write-only pseudo register. Write transactions to this register invalidate all DTB entries and reset the DTB not-last-used pointer to its initial state.

5.3.6 Dstream TB Invalidate Single Registers 0 and 1 – DTB_IS0,1

The Dstream translation buffer invalidate single registers (DTB_IS0 and DTB_IS1) are write-only pseudo registers through which software may invalidate a single entry in the DTB arrays. Writing a virtual page number to one of these registers invalidates any DTB entry in the corresponding memory pipeline which meets one of the following cri- teria:

•The DTB entry’s virtual page number matches DTB_IS[47:13] and its ASN field matches DTB_ASN[63:56].

•The DTB entry’s virtual page number matches DTB_IS[47:13] and its ASM bit is set.

Figure 5–29shows the Dstream translation buffer invalidate single registers.

Figure 5–29 Dstream Translation Buffer Invalidate Single Registers

63 48 47 13 12 0

VA[47:13]

LK99-0015A

21264/EV68A Hardware Reference Manual Internal Processor Registers 5–27