Currently the IDDRs are configured in SAME_EDGE_PIPELINED mode, but then
the negative data is delayed by an additional clock cycle. This is the same
behaviour as using the IDDR in SAME_EDGE mode.
Switching to SAME_EDGE mode removes extra pipelining registers while
maintaining the same behaviour.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The current implementation doesn't quite work right when the interface
clock is slower than the trigger clock and also causes timing issues.
Disable it temporarily until a proper CDC transfer is implemented.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The read and write interfaces of a AXI bus are independent other than that
they use the same clock. Yet when connecting a single read-only and a
single write-only interface to a Xilinx AXI interconnect it instantiates
arbitration logic between the two interfaces. This is dead logic and
unnecessarily utilizes the FPGAs resources.
Introduce a new helper module that takes a read-only and a write-only AXI
interface and combines them into a single read-write interface. The only
restriction here is that all three interfaces need to use the same clock.
This module is useful for systems which feature a read DMA and a write DMA.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The register read logic is not that complicated that it needs two extra
pipeline stages. It can easily be condensed into a single combinatorial and
still meet timing with large margins.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Disable registers in the register map which are not needed for this core.
This reduces the utilization of the core.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Not all peripherals use the GPIO register settings, but the registers still
take up a fair amount of space in the register map. Add options to allow to
disable them when not needed. This helps to reduce the utilization for
peripherals where these features are not needed.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Not all peripherals use the GPIO and START_CODE register settings, but the
registers still take up a fair amount of space in the register map. Add
options to allow to disable them when not needed. This helps to reduce the
utilization for peripherals where these features are not needed.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Depending on whether the core is configured for AXI4 or AXI3 mode the width
of the awlen/arlen signal is either 8 or 4 bit. At the moment this is only
considered in top-level module and all other modules use 8 bit internally.
This causes warnings about truncated signals in AXI3 mode, to resolve this
forward the width of the signal through the core.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Declaring local parameters in the module parameter list is not valid
verilog. For some reasons Vivado accepts it nevertheless so the code has
worked so far. But this is not true for other tools, so move the local
parameter definitions inside the module body.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
For experimentation, to solve a constraint scoping issue, split up the
ad_axi_ip_constraint file into separate constraints file, in function
of there parent module.
It seems that in the latest version a constant of "0" is no longer a valid
enablement dependency and "false" has be used instead.
Not setting the enablement dependency correctly results in the AXI port to
be assumed to be read-write rather than just read or write. This will
generate unnecessary logic for example in interconnects to which the DMA
controller is connected.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Xilinx recommends that all synchronizer flip-flops have
their ASYNC_REG property set to true in order to preserve the
synchronizer cells through any logic optimization during synthesis
and implementation.
Xilinx recommends that all synchronizer flip-flops have
their ASYNC_REG property set to true in order to preserve the
synchronizer cells through any logic optimization during synthesis
and implementation.
Add a human readable name and descriptor for the AXI DMAC core.This string
will appear in various places e.g. like the IP catalog. This is a purely
cosmetic change.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Add a register to the AXI DMAC register map which functions has a
identification register. The register contains the unique value of "DMAC"
(0x444d4143) and allows software to identify whether the peripheral mapped
at a certain address is an axi_dmac peripheral.
This is useful for detecting cases where the specified address contains an
error or is incorrect.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Lars-Peter Clausen
Adrian Costina
Istvan Csomortani
Rejeesh Kutty
Istvan Csomortani