For consistent simulation behavior it is recommended to annotate all source
files with a timescale. Add it to those where it is currently missing.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The cfg_links_disable register will mask the SYNC lines, disabled links
will always have a de-asserted SYNC (logic state HIGH).
The FSM will stay in CGS as long as there is one active link with an
asserted SYNC (logic state LOW).
Update the test bench to generate the SYNC signals in different clock
edges, so it can test all the possible scenarios.
For SYSREF handling there are now three possible modes.
1) Disabled. In this mode the LMFC is generated internally and all external
SYSREF edges are ignored. This mode should be used for subclass 0 when no
external sysref is available.
2) Continuous SYSREF. An external SYSREF signal is required and the LMFC is
aligned to the SYSREF signal. The SYSREF signal is continuously monitored
and if a edge unaligned to the previous edges is detected the LMFC is
re-aligned to the new edge.
3) Oneshot SYSREF. Oneshot SYSREF mode is similar to continuous SYSREF mode
except only the first edge is captured and all further edges are ignored,
re-alignment will not happen.
Both in continuous and oneshot signal at least one external sysref edge is
required before an LMFC is generated. All events that require an LMFC will
be delayed until a SYSREF edge has been captured. This is done to avoid
accidental re-alignment.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The ADI JESD204 link layer cores are a implementation of the JESD204 link
layer. They are responsible for handling the control signals (like SYNC and
SYSREF) and controlling the link state machine as well as performing
per-lane (de-)scrambling and character replacement.
Architecturally the cores are separated into two components.
1) Protocol processing cores (jesd204_rx, jesd204_tx). These cores take
care of the JESD204 protocol handling. They have configuration and status
ports that allows to configure their behaviour and monitor the current
state. The processing cores run entirely in the lane_rate/40 clock domain.
They have a upstream and a downstream port that accept and generate raw PHY
level data and transport level payload data (which is which depends on the
direction of the core).
2) Configuration interface cores (axi_jesd204_rx, axi_jesd204_tx). The
configuration interface cores provide a register map interface that allow
access to the to the configuration and status interfaces of the processing
cores. The configuration cores are responsible for implementing the clock
domain crossing between the lane_rate/40 and register map clock domain.
These new cores are compatible to all ADI converter products using the
JESD204 interface.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Lars-Peter Clausen
Istvan Csomortani