IDT 89HPES16NT2, User Manual

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IDT Transparent Mode Operation
PES16NT2 User Manual 9 - 16 April 15, 2008
Notes
PA_PMLIMIT - Prefetchable Memory Limit (0x026)
PA_PMBASEU - Prefetchable Memory Base Upper (0x028)
PA_PMLIMITU - Prefetchable Memory Limit Upper (0x02C)
3:1 Reserved RO 0x0 Reserved field.
15:4 PMBASE RW 0xFFF Prefetchable Memory Address Base. The PMBASE,
PMBASEU, PMLIMIT and PMLIMITU registers are used to
control the forwarding of prefetchable transactions
between the primary and secondary interfaces of the
bridge. This field contains A[31:20] of the lowest memory
address aligned on a 1MB boundary that is below the pri-
mary interface of the bridge. PMBASEU specifies the
remaining bits.
Bit
Field
Field
Name
Type
Default
Value
Description
0 PMCAP RO 0x1 Prefetchable Memory Capability. Indicates if the bridge
supports 32-bit or 64-bit prefetchable memory addressing.
This bit always reflects the value in the PMCAP field in the
PMBASE register.
3:1 Reserved RO 0x0 Reserved field.
15:4 PMLIMIT RW 0x0 Prefetchable Memory Address Limit. The PMBASE,
PMBASEU, PMLIMIT and PMLIMITU registers are used to
control the forwarding of prefetchable transactions
between the primary and secondary interfaces of the
bridge. This field contains A[31:20] of the highest memory
address, with A[19:0] assumed to be 0xF_FFFF, that is
below the primary interface of the bridge. PMLIMITU speci-
fies the remaining bits.
Bit
Field
Field
Name
Type
Default
Value
Description
31:0 PMBASEU RW 0xFFFF_FFFF Prefetchable Memory Address Base Upper. This field
specifies the upper 32-bits of PMBASE when 64-bit
addressing is used.
When the PMCAP field in the PMBASE register is cleared,
this field becomes read-only with a value of zero.
Bit
Field
Field
Name
Type
Default
Value
Description
31:0 PMLIMITU RW 0x0 Prefetchable Memory Address Limit Upper. This field
specifies the upper 32-bits of PMLIMIT.
When the PMCAP field in the PMBASE register is cleared,
this field becomes read-only with a value of zero.
Bit
Field
Field
Name
Type
Default
Value
Description