Chapter 15: Debugging
15–7
Link Hangs in L0 Due To Deassertion of tx_st_ready
June 2012
Altera Corporation
Stratix V Hard IP for PCI Express
rate[1:0]
[93:92]
[253:252]
The 2-bit encodings have the following meanings:
■
2’b01: Gen1 rate (2.5 Gbps)
■
2’b10: Gen2 rate (5.0 Gbps)
■
2’b13: Gen3 rate (8.0 Gbps)
■
2’b00: reserved
rxstatus0[2:0]
[91:89]
[251:249]
Receive status
<n>
. This signal encodes receive status
and error codes for the receive data stream and receiver
detection. The following encodings are defined:
■
3’b000: Received data OK.
■
3’b001: 1 SKP added.
■
3’b010: 1 SKP removed.
■
3’b011: Received detected.
■
3’b100: Both 8B/10B decode error and Receive
Disparity error.
■
3’b101: Elastic Buffer overflow.
■
3’b110: Elastic Buffer underflow.
■
3’b111: Reserved.
rxelecidle0
[88]
[248]
Indicates receiver detection of an electrical idle.
phystatus0
[87]
[247]
This signal communicates completion of several PHY
requests.
rxvalid0
[86]
[246]
Indicates symbol lock and valid data on rxdata0[31:0] and
rxdatak0[3:0]
rxblkst0
[85]
[245]
For Gen3 operation, indicates the start of a block.
rxsynchd0[1:0]
[84:83]
[244:243]
For Gen3 operation, specifies the block type. The
following encodings are defined:
■
2'b01: Ordered Set Block
■
2'b10: Data Block
rxdataskip0
[82]
[242]
For Gen3 operation. Allows the PCS to instruct the RX
interface to ignore the RX data interface for one clock
cycle. The following encodings are defined:
■
1’b0: RX data is invalid
■
1’b1: RX data is valid
rxdatak0[3:0]
[81:78]
[241:238]
These signals show the data and control received by Hard
P block from the other device.
rxdata0[31:0]
[77:46]
[237:206]
powerdown0[1:0]
[45:44]
[205:204]
The 4 encodings of these signals have the following
meanings:
■
2’b00: Phy is transmitting data.
■
2’b01: PHY is in electrical idle.
■
2’b10: PHY is in loopback mode.
■
2’b11: Illegal. Not defined.
rxpolarity0
[43]
[203]
When asserted, the PHY must invert the received data.
Table 15–3. PIPE Interface Signals (Part 2 of 3)
Signal Name
Lane 0
Lane 1
Description