The util_upack2 core is similar to the util_upack core. It unpacks, or
deinterleaves, a data stream onto multiple ports.
The upack2 core uses a streaming AXI interface for its data source instead
of a FIFO interface like the upack core uses.
On the output side the upack2 core uses a multi-port FIFO interface. There
is a single data request signal (fifo_rd_en) for all ports. But each port
can be individually enabled or disabled using the enable signals.
This modified architecture allows the upack2 core to better generate the
valid and underflow control signals to indicate whether data is available
in a response to a data request.
If fifo_rd_en is asserted and data is available the fifo_rd_valid signal
are asserted in the following clock cycle. The enabled fifo_rd_data ports
will be contain valid data during the same clock cycle as fifo_rd_valid is
asserted. During other clock cycles the output data is undefined. On
disabled ports the data is always undefined.
If no data is available instead the fifo_rd_underflow signal is asserted in
the following clock cycle and the output of all fifo_rd_data ports is
undefined.
This core is build using the common pack infrastructure. The core that is
specific to the upack2 core is mainly only responsible for generating the
control signals for the external interfaces.
The core is accompanied by a test bench that verifies correct behavior for
all possible combinations of enable masks.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Pack and unpack operations are very similar in structure as such it makes
sense for pack and unpack core to share a common infrastructure.
The infrastructure introduced in this patch is based on a routing network
which can implement the pack and unpack operations and grows with a
complexity of N * log(N) where N is the number of channels times the number
of samples per channel that are process in parallel.
The network is constructed from a set of similar stages composed of either
2x2 or 4x4 switches. Control signals for the switches are fully registered
and are generated one cycle in advance.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Add support for Vivado's simulator. By default the run script is using
the Icarus simulator.
If the user want to switch to another simulator, it can be explicitly
specify the required simulator tool in the SIMULATOR variable.
Currently, beside Icarus, Modelsim (SIMULATOR="modelsim") and Vivado's
xsim (SIMULATOR="xsim") is supported.
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>
By default inferred output reset signals have an active low polarity. The
axi_ad9361 rst output signal is active high though. Currently when
connecting it to a input reset with active high polarity will generate an
error in IPI.
Fix this by explicitly marking the polarity of the rst signal as active
high.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Replace the open-coded instances of a perfect shuffle in the DAC framer with
the new helper module.
Using the helper module gives well defined semantics and hopefully makes
the code easier to understand.
There are no changes in behavior.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The perfect shuffle is a common operation in data processing. Add a shared
module that implements this operation.
Having this in a shared module rather than open-coding every instance makes
sure that there are clear and well defined semantics associated with the
operation that are the same each time. This should ease review, maintenance and
understanding of the code.
The perfect shuffle splits the input vector into NUM_GROUPS groups and then
each group in WORDS_PER_GROUP. The output vector consists of
WORDS_PER_GROUP groups and each group has NUM_GROUPS words. The data is
remapped, so that the i-th word of the j-th word in the output vector is
the j-th word of the i-th group of the input vector.
The inverse operation of the perfect shuffle is the perfect shuffle with
both parameters swapped.
I.e. [perfect_suffle B A [perfect_shuffle A B data]] == data
Examples:
NUM_GROUPS = 2, WORDS_PER_GROUP = 4
[A B C D a b c d] => [A a B b C c D d]
NUM_GROUPS = 4, WORDS_PER_GROUP = 2
[A a B b C c D d] => [A B C D a b c d]
NUM_GROUPS = 3, WORDS_PER_GROUP = 2
[A B a b 1 2] => [A a 1 B b 2]
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The write logic (DMA side) has to be independent from the read logic (DAC side).
In general the FIFO is always ready for the DMA, and every DMA transaction will
interrupt the read-back process, and the module will stop sending data,
until the initialization is finished.
Bringing back the write address tot he DMA clock domain is totally
redundant, so delete it.
Expose the TX configurable driver ports, more specifically the
TX_DIFFCTRL, TX_POSTCURSORE and TX_PRECURSORE for software. This
provides a soft tunning capability of the transmit side of the
transceivers, in cases where the insertion loss of the channel is too
high or low, comparing to the default value supported by the default
configuration of the GTs.
You can find information about these configuration ports under the
section called 'TX Configurable Driver' in the GT transceivers user
guide. (UG476, UG576)
This commit does not contain any functional modification.
Because the wizard generates the attributes in binary, we should use
binary mode too, so we can compare different configurations more easily.
When we improve timing by modifying the implementation strategies,
the general rule of thumb is "less is always more".
Timing did not fail in synthesis, so we leaving the synthesis
strategy in default.
After several parallel runs with various strategies, the
"Performance_Explore" strategy gave the best result for
implementation.
Each individual link of a multi-link has its own sync signal. The top level
sync port that is created by the ad_xcvrcon function is always a single bit
single though.
This results in only the sync signal of the first link being routed while
others are ignored.
To fix this make sure that for multi-link setups the sync port is a vector
port with the width equal to the number of links.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>