Intel
®
81341 and 81342—Address Translation Unit (PCI-X)
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
104
Order Number: 315037-002US
2.7.3.1.2
Split Response Termination
As an initiator, the ATU may encounter this error condition in PCI-X mode when the
target signals a Split Response Termination.
Parity errors occurring during Split Response Terminations of Read Requests by the ATU
are recorded,
PERR#
is asserted (when enabled) and
SERR#
is asserted (when
enabled). Specifically, the following actions with the given constraints are taken by the
ATU:
•
PERR#
is asserted two clocks cycles (three clock cycles when operating in the PCI-
X mode) following the Split Response Termination in which the parity error is
detected on the bus. This is only done when the Parity Error Response bit in the
ATUCMD is set. When the ATU asserts
PERR#
, additional actions are taken:
— The Master Parity Error bit in the ATUSR is set.
— When the ATU PCI Master Parity Error Interrupt Mask Bit in the ATUIMR is clear,
set the PCI Master Parity Error bit in the ATUISR. When set, no action.
— When the
SERR#
Enable bit in the ATUCMD is set, and the Uncorrectable Data
Error Recover Enable bit in the PCIXCMD register is clear, assert
SERR#
,
otherwise no action. When the ATU asserts
SERR#,
additional actions are
taken:
Set the
SERR#
Asserted bit in the ATUSR.
When the ATU
SERR#
Asserted Interrupt Mask Bit in the ATUIMR is clear, set
the
SERR#
Asserted bit in the ATUISR. When set, no action.
When the ATU
SERR#
Detected Interrupt Enable Bit in the ATUCR is set, set
the
SERR#
Detected bit in the ATUISR. When clear, no action
• The Detected Parity Error bit in the ATUSR is set. When the ATU sets this bit,
additional actions are taken:
— When the ATU Detected Parity Error Interrupt Mask bit in the ATUIMR is clear,
set the Detected Parity Error bit in the ATUISR. When set, no action.
• For PCI-X Mode 2, update the
“ECC Control and Status Register - ECCCSR” on
, the
“ECC First Address Register - ECCFAR” on page 203
, the
Second Address Register - ECCSAR” on page 204
, and the
for the transaction.
The Outbound Read Request remains enqueued in the ATU since the completer is
initiating completion transactions that are associated with this request.