Interrupts for root ports, Completion side band signals – Altera Arria V Hard IP for PCI Express User Manual
Page 126

7–28
Chapter 7: IP Core Interfaces
Arria V Hard IP for PCI Express
Arria V Hard IP for PCI Express
December 2013
Altera Corporation
User Guide
Interrupts for Root Ports
Table 7–9
describes the signals available to a Root Port to handle interrupts.
Completion Side Band Signals
describes the signals that comprise the completion side band signals for the
Avalon-ST interface. The Arria V Hard IP for PCI Express provides a completion
error interface that the Application Layer can use to report errors, such as
programming model errors. When the Application Layer detects an error, it can assert
the appropriate
cpl_err
bit to indicate what kind of error to log. The Hard IP sets the
appropriate status bits for the errors in the Configuration Space, and automatically
sends error messages in accordance with the
PCI Express Base Specification
. Note that
the Application Layer is responsible for sending the completion with the appropriate
completion status value for non-posted requests. Refer to
for information on errors that are automatically detected and handled by the Hard IP.
app_msi_func[2:0]
I
Indicates which function is asserting an interrupt with 0 corresponding to function 0, 1
corresponding to function 1, and so on.
app_int_sts_vec[7:0]
I
Level active interrupt signal. Bit 0 corresponds to function 0, and so on. Drives the INTx
line for that function. The core maps this status to INT A/B/C/D according to each
function’s
Interrupt_Pin
register. The core internally wire-ORs the INT requests from
all sources, and generates INT MSGs on the rising/falling edges of the wire-ORed result.
The core logs the
tl_app_int_sts_vec
status in each functions’ PCI Status register.
Table 7–8. Interrupt Signals for Endpoints (Part 2 of 2)
Signal
I/O
Description
Table 7–9. Interrupt Signals for Root Ports
Signal
I/O
Description
int_status[3:0]
O
These signals drive legacy interrupts to the Application Layer as follows:
■
int_status[0]: interrupt signal A
■
int_status[1]: interrupt signal B
■
int_status[2]: interrupt signal C
■
int_status[3]: interrupt signal D
aer_msi_num[4:0]
I
Advanced error reporting (AER) MSI number. Provides the low-order message data bits to
be sent in the message data field of the MSI messages associated with the AER capability
structure. Only bits that are enabled by the MSI Message Control register are used. For
Root Ports only.
pex_msi_num[4:0]
I
Power management MSI number. This signal provides the low-order message data bits to
be sent in the message data field of MSI messages associated with the PCI Express
capability structure. Only bits that are enabled by the MSI Message Control register are
used. For Root Ports only.
serr_out
O
System Error: This signal only applies to Root Port designs that report each system error
detected, assuming the proper enabling bits are asserted in the
Root
Control
register
and the
Device
Control
register. If enabled,
serr_out
is asserted for a single clock
cycle when a system error occurs. System errors are described in the
. in the
Root
Control register
.