Altera Stratix V Avalon-MM Interface for PCIe Solutions User Manual
Page 45
Signal
Direction
Description
ko_cpl_spc_
header[7:0]
Output
The Application Layer can use this signal to build circuitry to
prevent RX buffer overflow for completion headers. Endpoints
must advertise infinite space for completion headers; however,
RX buffer space is finite.
ko_cpl_spc_header
is a static signal
that indicates the total number of completion headers that can be
stored in the RX buffer.
l2_exit
Output
L2 exit. This signal is active low and otherwise remains high. It is
asserted for one cycle (changing value from 1 to 0 and back to 1)
after the LTSSM transitions from l2.idle to detect. When this
pulse is asserted, the Application Layer should generate an
internal reset signal that is asserted for at least 32 cycles.
lane_act[3:0]
Output
Lane Active Mode: This signal indicates the number of lanes that
configured during link training. The following encodings are
defined:
• 4’b0001: 1 lane
• 4’b0010: 2 lanes
• 4’b0100: 4 lanes
• 4’b1000: 8 lanes
ltssmstate[4:0]
Output
LTSSM state: The LTSSM state machine encoding defines the
following states:
• 00000: Detect.Quiet
• 00001: Detect.Active
• 00010: Polling.Active
• 00011: Polling.Compliance
• 00100: Polling.Configuration
• 00101: Polling.Speed
• 00110: config.Linkwidthstart
• 00111: Config.Linkaccept
• 01000: Config.Lanenumaccept
• 01001: Config.Lanenumwait
• 01010: Config.Complete
• 01011: Config.Idle
• 01100: Recovery.Rcvlock
• 01101: Recovery.Rcvconfig
• 01110: Recovery.Idle
• 01111: L0
• 10000: Disable
• 10001: Loopback.Entry
• 10010: Loopback.Active
4-12
Reset
UG-01097_avmm
2014.12.15
Altera Corporation
64- or 128-Bit Avalon-MM Interface to the Application Layer