Altera Arria 10 Avalon-ST User Manual
Page 173

• The Transaction Layer sends poisoned TLPs on the Avalon-ST RX interface for completions and error
handling by the Application Layer. These errors are not logged in the Configuration Space error
registers.
• The Transaction Layer discards TLPs that violate RX credit limits. The Transaction Layers signals this
error by asserting the
err_tlrcvovf
output signal and logging it in the
Uncorrectable Error
Status
,
AER Header Log
, and
First Error Pointer
Registers
.
• The Transaction Layer indicates Data Link and internal errors with the real-time error output signals
cfgbp_err_
*. These errors are also logged in the
Uncorrectable Error Status
,
AER Header Log
,
and
First Error Pointer
Registers
.
The Transaction Layer uses error flags to signal the Application Layer with real-time error status output
signals. The Application Layer can monitor these flags to determine when the Transaction Layer has
detected a Malformed TLP, Corrected Error, or internal error. In addition, the Application Layer can read
the Transaction Layer’s AER information such as
AER Header Log
and
First Error Pointer
Registers
using the LMI bus.
• Real-time error signals are routed to the Application Layer using the error status output signals listed
in the “Configuration Space Bypass Mode Output Signals” on page 8–44.
• Two sideband signals
uncorr_err_reg_sts
and
corr_err_reg_sts
indicate that an error has been
logged in the
Uncorrectable Error Status
or
Correctable Error Status
Register
. The Applica‐
tion Layer can read these
Uncorrectable
or
Correctable Error Status
Registers
,
AER Header
Log
, and
First Error Pointers
using the LMI bus to retrieve information. The
uncorr_err_reg_sts
and
corr_err_reg_sts
signals remain asserted until the Application Layer
clears the corresponding status register. Proper logging requires that the Application Layer set the
appropriate Configuration Space registers in the Transaction Layer using the LMI bus. The Applica‐
tion Layer must set the
Uncorrectable
and
Correctable
Error Mask
and
Uncorrec
table Error
Severity
error reporting bits appropriately so that the errors are logged appropriately internal to the
Arria 10 Hard IP for PCI Express. The settings of the
Uncorrectable
and
Correctable Error Mask
,
and
Uncorrectable Error Severity
error reporting bits do not affect the real-time error output
signals. The Application Layer must also log these errors in the soft Configuration Space and send
error Messages.
• For more information about error handling, refer to the PCI Express Base Specification, Revision 2.0 or
3.0.
• The sideband signal
root_err_reg_sts
indicates that an error is logged in the
Root Error Status
Register
. The Application Layer can read the
Root Error Status
Register
and the
Error Source
Identification Register
using the LMI bus to retrieve information about the errors. The
root_err_reg_sts
signal remains asserted until the Application Layer clears the corresponding
status register using the LMI bus. The Application Layer must set the
Uncorrectable
and
Correct-
able
Error Mask
,
Uncorrectable Error Severity
, and
Device Control Register
error reporting
bits appropriately so that the errors are logged appropriately in the Arria 10 Hard IP for PCI Express
IP Core. The settings of the
Uncorrectable
and
Correctable Error Mask
,
Uncorrectable Error
Severity
, and
Device Control Register
error reporting bits do not affect the real-time error output
signals. The Application Layer must also log these errors in the soft Configuration Space and send
error Messages.
Related Information
UG-01145_avst
2014.08.18
Error Checking and Handling in Configuration Space Bypass Mode
11-9
IP Core Architecture
Altera Corporation