Data mover/ src axis changes
Request rewind ID if TLAST received during non-last burst
Consume (ignore) descriptors until last segment received
Block descriptors towards destination until last segment received
Request generator changes
Rewind the burst ID if rewind request received
Consume (ignore) descriptors until last segment received
If TLAST happened on last segment replay next transfer (in progress or
completed) with the adjusted ID
Create completion requests for ignored segments
Response generator changes
Track requests
Complete segments which got ignored
Length of partial transfers are stored in a queue for SW reads.
The presence of partial transfer is indicated by a status bit.
The reporting can be enabled by a control bit.
The progress of any transfer can be followed by a debug register.
Vivado recognises .h files as C header files,
the expected extension for Verilog Header is .vh
This causes issues in simulating block designs since these files
won't be exported for the simulation even if they are
part of the simulation fileset.
Currently the DMAC uses a simple FIFO as the store-and-forward buffer. The
FIFO handshaking is beat based whereas the remainder of the DMAC is burst
based. This means that additional control signals have to be combined with
the FIFO handshaking signal to generate the external handshaking signals.
Re-work the store-and-forward buffer to utilize a BRAM that is subdivided
into N segments. Where N is the maximum number of bursts that can be stored
in the buffer and each segment has the size of the maximum burst length.
Each segment stores the data associated with one burst and even when the
burst is shorter than the maximum burst length the next burst will be
stored in the next segment.
The new store-and-forward buffer takes care of generating all the
handshaking signals. This means handshaking is generated in a central place
and does not have to be combined from multiple data-paths simplifying the
overall logic.
The new store-and-forward buffer also takes care of data width up- and
down-sizing in case that the source and sink modules have a different data
width. This tighter integration will allow future enhancements like using
asymmetric memory.
This re-work lays the foundation of future enhancements to the DMA like
support for un-aligned transfers and early transfer abort which would have
been much more difficult to implement with the previous architecture.
In addition it significantly reduces the resource utilization of the
store-and-forward buffer and allows for better timing due to reduced
combinatorial path lengths.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The DMAC allows a transfer to be aborted. When a transfer is aborted the
DMAC shuts down as fast as possible while still completing any pending
transactions as required by the protocol specifications of the port. E.g.
for AXI-MM this means to complete all outstanding bursts.
Once the DMAC has entered an idle state a special synchronization signal is
send to all modules. This synchronization signal instructs them to flush
the pipeline and remove any stale data and metadata associated with the
aborted transfer. Once all data has been flushed the DMAC enters the
shutdown state and is ready for the next transfer.
In addition each module has a reset that resets the modules state and is
used at system startup to bring them into a consistent state.
Re-work the shutdown process to instead of flushing the pipeline re-use the
startup reset signal also for shutdown.
To manage the reset signal generation introduce the reset manager module.
It contains a state machine that will assert the reset signals in the
correct order and for the appropriate duration in case of a transfer
shutdown.
The reset signal is asserted in all domains until it has been asserted for
at least 4 clock cycles in the slowest domain. This ensures that the reset
signal is not de-asserted in the faster domains before the slower domains
have had a chance to process the reset signal.
In addition the reset signal is de-asserted in the opposite direction of
the data flow. This ensures that the data sink is ready to receive data
before the data source can start sending data. This simplifies the internal
handshaking.
This approach has multiple advantages.
* Issuing a reset and removing all state takes less time than
explicitly flushing one sample per clock cycle at a time.
* It simplifies the logic in the faster clock domains at the expense of
more complicated logic in the slower control clock domain. This allows
for higher fMax on the data paths.
* Less signals to synchronize from the control domain to the data domains
The implementation of the pause mode has also slightly changed. Pause is
now a simple disable of the data domains. When the transfer is resumed
after a pause the data domains are re-enabled and continue at their
previous state.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Move the transfer logic, including the 2d module, into its own sub-module.
This allows testing of the full transfer logic independently of the
register map logic.
The top-level module now only instantiates the register map and transfer
module, but does not have any logic on its own.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Split the register map code into a separate sub-module instead of having it
as part of the top-level axi_dmac.v file.
This makes it easier to component test the register map behavior
independently from the DMA transfer logic.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
When the DMAC is used in async clock domains the data FIFO instantiate
an ad_mem component to handle properly the clock crossing.
For Intel, this mode is used only in FMCJESDADC1 designs but without this
an error could appear in other projects too if the user reconfigures the core.
Currently the individual IP core dependencies are tracked inside the
library Makefile for Xilinx IPs and the project Makefiles only reference
the IP cores.
For Altera on the other hand the individual dependencies are tracked inside
the project Makefile. This leads to a lot of duplicated lists and also
means that the project Makefiles need to be regenerated when one of the IP
cores changes their files.
Change the Altera projects to a similar scheme than the Xilinx projects.
The projects themselves only reference the library as a whole as their
dependency while the library Makefile references the individual source
dependencies.
Since on Altera there is no target that has to be generated create a dummy
target called ".timestamp_altera" who's only purpose is to have a timestamp
that is greater or equal to the timestamp of all of the IP core files. This
means the project Makefile can have a dependency on this file and make sure
that the project will be rebuild if any of the files in the library
changes.
This patch contains quite a bit of churn, but hopefully it reduces the
amount of churn in the future when modifying Altera IP cores.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
This reduces the amount of boilerplate code that is present in these
Makefiles by a lot.
It also makes it possible to update the Makefile rules in future without
having to re-generate all the Makefiles.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Move the CDC helper modules to a dedicated helper modules. This makes it
possible to reference them without having to use file paths that go outside
of the referencing project's directory.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
When having multiple DMA cores sharing the same constraint file Vivado
seems to apply the constraints from the first core to all the other cores
when re-running synthesis and implementation from within the Vivado GUI.
This causes wrong timing constraints if the DMA cores have different
configurations. To avoid this issue use a TTCL template that generates a
custom constraint file for each DMA core instance.
This also allows us to drop the asynchronous clock detection hack from the
constraint file and move it to the template and only generate the CDC
constraints if the clock domains are asynchronous.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Clean ran for a project will clean only the project files.
Clean-all ran for a project will clean also the library files on which the project depends.
The clean commands will only remove specific files and directories.
The top Makefile allows several options(per suggestion from jameyhicks):
make fmcomms1.zed will run "make all" in projects/fmcomms1/zed/
make clean will run "make clean" for all the projects
make clean-all will run "make clean" for all the projects and libraries
make lib will run "make all" for the library files
Move the axi_repack block to its own module. This allows it to use it
outside of the DMA controller.
Also rename it to util_axis_resize to better reflect its function.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Laszlo Nagy
Lars-Peter Clausen
Istvan Csomortani
Adrian Costina
Rejeesh Kutty