IDT PCI Express 89HPES32NT24xG2, User Manual, Page: 320 / 744

IDT DMA Controller
PES32NT24xG2 User Manual 15 - 32 January 30, 2013
Notes
The sub-sections below describe in detail the DMA function’s error handling for the cases listed in Table
15.12. The error handling described in this section is in addition to the ‘action taken’ column in Table 15.12.
Poisoned TLP Reception
The DMA handles the reception of a poisoned TLP as follows:
– If the poisoned TLP is a memory write request that falls into one of the DMA’s BAR apertures, the
TLP is handled as an unsupported request (see section Reception of a Request TLP That is
Unsupported on page 15-33).
– If the poisoned TLP is a configuration write request, the TLP is handled as an unsupported request
(see section Reception of a Request TLP That is Unsupported on page 15-33).
– If the poisoned TLP is a completion TLP associated with an outstanding descriptor read request
by a DMA channel, the Descriptor Poisoned Error (DSCP) bit is set in the corresponding DMA
Channel Error Status (DMACxERRSTS) register.
• The poisoned completion TLP is discarded.
• The DMA channel aborts descriptor processing.
– If the poisoned TLP is a completion TLP associated with an outstanding data read request by a
DMA channel, the Data Poisoned Error (DATP) bit is set in the corresponding DMACxERRSTS
register and the behavior is determined by the Poisoned Completion Reception Control (PCRC)
field in the DMACxCFG register.
Note: The reception of any other type of poisoned TLP is handled as an unsupported request or unex-
pected completion.
ECRC Errors
Refer to section ECRC Support on page 15-27 for details on ECRC support in the DMA function.
ECRC errors are non-channel specific. Therefore, when an ECRC error occurs, all DMA channels that
are processing a descriptor abort processing.
– Due to a design error, DMA channels that are idle at the time an ECRC error is detected also abort
processing (e.g., the Abort bit is set in the DMACxSTS register).
Flow control pro-
tocol error 2.6.1 Not applicable. The DMA function does not check for any flow control protocol
errors.
Malformed TLP
Received See sec-
tion Mal-
formed
TLP Errors
on page
15-34 No N/A
(always non-
advisory) No
(DMA
channels
are not
affected)
Uncorrectable error processing
Offending TLP is nullified.
See section Malformed TLP
Errors on page 15-34.
Internal Errors Section 6.2 No N/A (always
non-advisory) No
(All DMA
channels
are
affected)
Refer to section Internal Errors
on page 4-16.
1.
Refer to PCI Express Base Specification Revision 2.1., March 4, 2009, PCI-SIG.
2.
Refer to section ECRC Support on page 15-27.
3.
If the completion is unexpected, then it is handled as an unexpected completion received error.
4.
If the completion is unexpected, then it is handled as an unexpected completion received error.
Error
Condition
PCI
Express
Base
Spec
1
Section
Function-
Specific
Error
Role
Based
(Advisory)
Error
Reporting
Condition
Channel-
Specific
Error
Action Taken
Table 15.12 PCI Express Errors Detected by the DMA Function’s Transaction Layer (Part 3 of 3)