The MAX_BYTES_PER_BURST option allows to configure the maximum bytes that
are part of a burst. This can be an arbitrary value.
At the same time there is a limit of how many bytes can be supported by the
memory buses. A AXI3 interface supports a maximum of 16 beats per burst
and a AXI4 interface supports a maximum of 256 beats per burst.
At the moment the it is possible to specify a MAX_BYTES_PER_BURST value
that exceeds what can be supported by the AXI memory-mapped bus. If that is
the case undefined behavior will occur and the DMAC will function
incorrectly.
To avoid this make sure that the MAX_BYTES_PER_BURST value does not exceed
the maximum that can be supported by the interfaces.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The width of the AXI burst length field depends on the AXI standard
version. For AXI3 the width is 4 bits allowing a maximum burst length of 16
beats, for AXI4 it is 8 bits wide allowing a maximum burst length of 256
beats.
At the moment the width of the length signals are determined by type of the
source AXI interface, even if the source interface type is not AXI. This
means if the source interface is set to AXI3 and the destination interface
is set to AXI4 the internal width of the signal for all interfaces will be
4 bits. This leads to a truncation of the destination bus length field,
which is supposed to be 8 bits.
If burst are generated that are longer than 16 beats the upper bits of the
length signal will be truncated. The result of this will be that the
external AXI slave interface (e.g. the DDR memory) and the internal logic
in the DMA disagree about burst length. The DMA will eventually lock up
when its internal buffers are full.
To avoid this issue have different configuration parameters for the source
and destination interface that configure the AXI bus length field width.
This way one of the interfaces can be configured for AXI3 and the other for
AXI4 without interfering with each other.
Fixes: commit 495d2f3056 ("axi_dmac: Propagate awlen/arlen width through the core")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Exposed AXI3 interface on the Intel version of the IP for UI and feature consistency.
Some of the signals that are defined as optional in the AMBA standard
are marked as mandatory in Qsys in case of AXI3. Because of this such signals
were added to the interface of the DMAC and driven with default values.
For Xilinx in order to keep existing behavior the newly added signals
are hidden from the interface.
New parameters are added to define the width of the AXI transaction IDs;
these are hidden from the UI; We can add them to the UI if the fixed size
of the IDs will cause port incompatibility issues.
The primary use-case of the DMA controller is in non-2D mode. Make this the
default, since allows projects to instantiate the controller with the
default configuration without having to explicitly disable 2D support.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Add some limit TLAST support for the streaming AXI source interface. An
asserted TLAST signal marks the end of a packet and the following data beat
is the first beat for the next packet.
Currently the DMAC does not support for completing a transfer before all
requested bytes have been transferred. So the way this limited TLAST
support is implemented is by filling the remainder of the buffer with 0x00.
While the DMAC is busy filling the buffer with zeros back-pressure is
asserted on the external streaming AXI interface by keeping TREADY
de-asserted.
The end of a buffer is marked by a transfer that has the last bit set in
the FLAGS control register.
In the future we might add support for transfer completion before all
requested bytes have been transferred.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The current layout of the debug ID register assumes that the ID_WIDTH is 3.
Change things so that the padding 0 width depends on the ID_WIDTH
parameter so that we end up with the same register layout regardless of the
value of ID_WIDTH.
Also split things into two registers, this allows for an ID_WIDTH up to 8
(which should hopefully be enough for all practical applications).
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The AXI specification that the minimum address space size is 4k, make sure
the axi_dmac adheres to this.
Internally the register space is still 2k. This means the upper and lower
2k of the axi4lite register space will map to the same internal registers.
Software must not rely on this and only access the lower 2k to enable
compatibility in case the internal space grows in the future.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Make sure that the right hand side expression of assignments is not wider
than the target signal. This avoids warnings about implicit truncations.
None of these changes affect the behaviour, just fixes some warnings about
implicit signal truncation.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
All the hdl (verilog and vhdl) source files were updated. If a file did not
have any license, it was added into it. Files, which were generated by
a tool (like Matlab) or were took over from other source (like opencores.org),
were unchanged.
New license looks as follows:
Copyright 2014 - 2017 (c) Analog Devices, Inc. All rights reserved.
Each core or library found in this collection may have its own licensing terms.
The user should keep this in in mind while exploring these cores.
Redistribution and use in source and binary forms,
with or without modification of this file, are permitted under the terms of either
(at the option of the user):
1. The GNU General Public License version 2 as published by the
Free Software Foundation, which can be found in the top level directory, or at:
https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html
OR
2. An ADI specific BSD license as noted in the top level directory, or on-line at:
https://github.com/analogdevicesinc/hdl/blob/dev/LICENSE
up_rdata is qualified by the up_rack signal. There is no need to reset it
since by the time the signal is read the reset value has already been
overwritten anyway.
Also gate the up_rdata registers if no read operation is in progress. In
this case any changes would be ignored anyway.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The AXI DMAC peripheral only uses 11-bit of the register map interface
address. Reducing the signal width to this value allows the scripts to
correctly infer the size of the register map.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Currently the AXI address width of the DMA is always 32-bit. But not all
address spaces are so large that they require 32-bit to address all memory.
Extract the size of the address space that the DMA is connected too and
configure reduce the address size to the minimum required to address the
full address space.
This slightly reduces utilization.
If no mapped address space can be found the default of 32 bits is used for
the address.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The debug registers are useful during development but are rarely used in a
production design. Add a option that allows to disable them, this reduces
the resource utilization of the DMAC.
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>
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>
The address width for the AXI-Lite configuration bus for the core is only
14 bit. Remove the upper unused bits from the public interface.
This allows infrastructure code to know about this and it might be able to
perform optimizations of the interconnect based on this.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Move the clock and reset signals of the m_axi_src interface next to the
other signals in the module definition.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
This control signal can be overwritten by the up_axis_xlast/up_axis_xlast_en bits, in order to create a single stream, which is contains multiple streams.
This can be use to fill up the DACFIFO module.
We need to make sure to not prematurely de-assert the s_valid signal for the
request splitter when disabling the DMAC. Otherwise it is possible that
under certain conditions the DMAC is disabled with a partially accepted
request and when it is enabled again it will continue in an inconsistent
state which can lead to transfer corruption or pipeline stalls.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The dummy a{r,w}len fields should have the same width as the real a{w,r}len
fields in order to not break auto AXI bus version detection.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
We can remove the Altera toplevel wrapper if we switch the axi4 control bus
to axi4lite and add the few missing signals that are required by the Altera
interconnect to both the control and the data buses.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
This is unused and unneeded. The AXI interconnect will make sure that a
peripheral only gets requests that are meant for it, there is no need to
check the address in the peripheral itself.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Make sure that the address generator behaves correctly when the buswidth is not
64-bit. Also since the source and destination can have different widths add
separate parameters for source and destination address alignment.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The read data also becomes available only with a delay of one clock cycle,
sending the ack too early will result in bogus register reads.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Lars-Peter Clausen
Laszlo Nagy
Istvan Csomortani
AndreiGrozav
Rejeesh Kutty